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UNITED STATES DEPARTMENT OF AGRICULTURE

Agriculture Handbook No. 57 June 1953

Farm Planners^

Engineering Handbook

for the Upper Mississippi Region

SOIL CONSERVATION SERVICE

Upper Mississippi Region, Regional Office, Milwaukee, Wis.

For sale by the Superintendent of Documents, U. S. Government Printing Office, Washington 25, D. C. - - Price J1.50
FARM PLANNERS' ENGINEERING HANDBOOK

FOR THE UPPER MISSISSIPPI REGION

CONTENTS

Part Subject Page Part Subject Page

PART 1 ENGINEERING SURVEYS

1.10 General 1-1

1.20 Measurement of Horizontal Distances 1-1

1.30 Differential Leveling 1-7

1. ho Topographic Surveys 1-24

1.50 Job Layout 1-29

1.60 Field Books 1-3Ö

PART 2 PREPARATION OF ENGINEERING DATA SHEETS

2.10 General 2-1

2.20 Purpose 2-1

2.30 Information and Materials Needed 2-1

2.40 Drawing and Drafting Standards 2-4

2.50 Watershed Location Map 2-12

2.60 Location Plan 2-l4

PART 3 RAINFALL - RUNOFF - SPRING AND STREAM FLOW MEASUREMENTS

3 .10 Erosion Control 3-1

3 .20 Drainage Runoff 3-5

3 .30 Measuring Stream and Spring Flows 3-5

PART 4 FARM PONDS

4.10 General 4-1

4.20 Selecting the Pond Site 4-2

4.30 Surveys 4-4

4.40 Design 4-4

4.50 Staking 4-19

4.60 Construction 4-19

4.70 Maintenance 4-22

PART 5 SPRING AND HYDRAULIC RAMS

5 .10 General, Springs 5-1

5 .20 Developing a Spring 5-1

5 .30 General; Hydraulic Rams 5-6

5 .40 Operation 5-6

5 .50 Des ign 5-6

PART 6 WELLS

6.10 General 6-1

6.20 Construction of Well 6-1

6.30 Selection of Piamps 6-6

6.40 Power Requirements 6-6

PART 7 CONCRETE AND MASONRY STRUCTURES

7,10 General 7-1

7.20 Component Parts of Structures 7-1

7.30 Common Types of Structures 7-3

7.40 Structure Data Sheets and Designs 7-7

7.50 Preliminary Cost Estimates 7-l4

7.60 How to Promote Good Quality in Construction 7-19

7.70 Structiire Maintenance 7-19

PART 8 TERRACING

8.10 General 8rl

8.20 Planning the Terrace System 8-2

8.30 Staking Terraces 8-5

8.40 Construction of Terraces 8-5

8.50 Checking Finished Terrace 8-10

8.60 Terrace Maintenance 8-13

8.70 Plowing Terraced Fields 8-13

8.80 Preparing Seedbed and Planting Crops on

Terraced Land 8-17

8.90 Harvesting Crops on Terraced Land 8-25

PART 9 DIVERSIONS

9.10 General 9-1

- 9.20 Design of Diversions 9-2

9-30 Layout and Construction of Diversion

Channels 9-4

9.40 Maintenance of Diversion Channels 9-4

PART 10 VEGETATED OUTLETS AND WATERCOURSES

10 .10 Water Disposal 10-1

10.20 Watercourse Location 10-2

10 .30 Design 10-2

10 .40 Construction of Watercourses 10-7

10.50 Sod Chute 10-13

PART 11 LAND DRAINAGE

11.10 Introduction 11-1

11.20 Effects and Benefits of Land Drainage 11-1

11.30 Preliminary Investigation of Drainage Jobs. 11-5

11.40 Drainage Outlets 11-9

11.50 Open Outlet Ditches 11-11

11.60 Surface Drainage 11-27

11.70 Tile Drainage II-58

11.80 Culverts 11-93

PART 12 IRRIGATION

12.10 General 12-1

12.20 Water Supply 12-6

12.30 General Types of Irrigation 12-7

12.40 Adaptation of Types of Irrigation to the

Region 12-9

12.50 Costs of Irrigation Systems 12-14

PART 13 STREAMBANK EROSION CONTROL

13 .10 General 13-1

13 .20 Investigations 13-I

13 .30 Treatment 13-2
FOREWORD

This handbook has been prepared for soil conservationists and other

agricultural workers having little or no training in the field of engineering. Efforts have been directed toward supplying engineering information which the soil conservationist can readily use in developing conservation measures for farm land.

Highly technical engineering information has either been intentionally

omitted or prepared in such form that it can be used with a minimum of

effort and study. Charts, tables, and illustrations have been provided

to reduce the need for narrative material wherever possible.

Users of the handbook should keep in mind that the occasional reference

to a drawing or technical note pertains to materials provided by the

Soil Conservation Service to its field personnel for their use in carrying out their responsibilities. These additional references will not be

available to workers outside the Service.

It is the hope of the authors that this handbook will fulfill a need

which has long been recognized. Revision of the material incorporated

will be made from time to time as the need becomes apparent.

MiIwaukee, Wis.

April 1953

Edwin Freyburger

Acting Asst. Regional Director, Engineering

upper Mississippi Region

Soil Conservation Service
1-1

PAET 1

ENGIWEERIMG SUKVJbiïS

1,10 GENERAL

1.11 Pirrpose

a. This part of the engineering handbook provides:

(1) Detailed directions for the care and use of surveying

instruments by soil conservationists.

(2) Step-by-step description of practical methods of. surveying applicable to soil conservation activities.

b. It should be remembered that there can be no substitute for

experience in surveying. Skill in s\irveying comes only with

practice as in using a typewriter or driving an automobile.

The beginner must continually review surveying procedures and

conscientiously try to put them into pi^ctice until the operations become very nearly automatic. Above all, he must not

become discouraged by initial mistakes. He must check and

re-check his work until he is store it is correct. It has been

said "a good engineer is one who assumes he is wrong, tries

every way he can think of to prove he is wrong, and when he cannot thus prove he is wrong, cautiously concedes he may be right.''

1.12 Scope

Only basic principles of surveying will be explained in Part 1.

Details of procedures applicable to a specific practice will be

explained in the part of handbook dealing with that practice.

1.20 MEASUBIMENT OP HORIZONTAL DISTANCES

1.21 The procedures for measuring horizontal distances by pacing,

chaining, and stadia are:

a. Pacing may be used for approximate measurement when an error

of two feet per hundred feet is permissible. Measurement by

pacing consists of counting the number of steps between two

points and multiplying the number by a predetermined "pace

factor." Pace factors will us\ially vary between individuals.

Each person having occasion to use this measurement method

should determine his individual pace factor.

The pace factor for each individual is the average distance

in feet per step. It can best be determined by pacing a

measured distance (usually 500 feet) several times. It should

be paced enough times so the number of paces for the distance
1-2

does not vary over 2 or 3 paces. The "pace factor" then would

be the distance in feet divided by the niomber of payees.

Scame people prefer to use a stride in place of a pace. It consists of 2 paces, so the "stride factor" would be two times the

"pace factor."

Measurement by pacing for terrace and diversion layouts, preliminary profile work, and gridding for surface drainage surveys,

is generally permissible.

b. "Chaining" is the method of measuring horizontal distances

with a steel tape. It is the most common method known and should

be used for most measurements in order to get required accuracy.

, Survey lines are measured or chained by stations. The distance

between full stations is 100 feet. For this reason most steel

tapes in use are 100 feet long. When a distance is referred to

as so many stations, it means that n\jmber of 100-foot lengths.

The fractional part of a distance between a full station is

called a plus station. Fractions of a foot are indicated by

decimals, either to the nearest 0.1 foot or 0.01 foot, depending

upon the accuracy of measurement required. For example, a point

on a line 309.2 feet beyond station 10+00 is indicated as station

13+09.2.

Stakes set alonig the line are marked with waterproof lumber

crayon known as "keel." Markings are placed on the face of

stakes so that as a person walks along the line in the direction

of progressive stationing, the station markings are readily seen

as each stake is approached.

Accurate chaining with a steel tape requires skill on the part

of the chainmen in use of plumb bobs, steel marking pins, range

poles, hand levels and tension indicator apparatus. No attenpt

will be made to outline details for highly acciirate chaining

methods, since most chaining done for small-size conservation

Jobs will allow an error of 0.3 to 0.5 foot per 100 feet. This

handbook is written for execution of the less difficult conservation work (Class E). In order to obtain sufficient

accuracy the following should be observed:

Keep tape on line being measured.

Keep uniform tension on tape for each measurement.

"Break" chain on slopes above 10^.

Accurately mark each station.

Keep accurate count of the stations.

The following procedure is generally used for chaining out a

line within this accuracy limit.
1-3

(1) The line to be measured may be a meandering line along

a drainage ditch or gully channel or it may be a straight

line in a pre-determined direction. In the foniier case the

measurements are taken parallel, or nearly so, to the meandering line; but in the latter case a range pole is set

ahead on the line as far as can be seen, or the direction is

marked by a tree, fence post, or other convenient point.

This mark is used in sighting in a straight line from the

point of beginning.

(2) For purposes of this explanation it will be assumed a

straight line is to be measured, and a *stake has been set at

the point of beginning marked 0+00. (See paragraph 1.37b2

for other methods of stationing the beginning station.)

(3) The head chainman takes the zero end of the tape and

advances in the general direction of the line to be measured.

When he has gone the length of the tape the rear chainman

will have observed that the 100-foot end is opposite the

beginning point and he calls out "chain."

(k) The rear chainman then sights in the head chainman on

the line to be measured and holds the 100-foot mark of the

tape exactly on the beginning stake. Tne head chainman pulls

the tape straight and reasonably tight and sets a stake or

pin exactly at the "zero" end of the tape.

(5) The rear chainman calls out the number of his station

(in this case 0+00) and the head chainman marks his stake

1+00, indicating one station has been measured.

(6) Both chainmen then move forward along the line to be

measured and the rear chainman again calls "chain" when the

head chainman has gone forward 100 feet. The line is sighted

in, stakes set and marked as before, each time the rear

chainman calls off his station to the head chainman and the

new station is given the next consecutive number and so

marked.

For chaining of this order of accuracy it is not necessary to

hold the tape level when measuring up or down slopes under about

6 percent. On grades steeper than 6 percent the uphill end of

the tape should be held on the ground and the chainman at the

other end should hold the end of the tape so that it is level or

at least as high as the chainman can reach and "plumb" down by

sighting in. On grades over 10 percent the chain should be

"broken" in such convenient lengths that it can be held approximately level, plumbing down to the ground. Figure 1.1 illustrates the process of breaking chain and indicates the errors

which can occur if this is not done on steep slopes.

Where a line is to be measured on which no stakes are set the

head chainman is responsible for keeping count of the number of

stations. The procedure is the same as that used in ordinary

surveying by means of 11 chaining pins.
1-k

PLUMB LINE-EYED IN - CAN BE CHECKED

BY DROPPING A PENCIL OR A PEBBLE

STA. 11 + 00

-200-201 FT.-DISTANCE MEASURED BY "BREAKING" CHAIN AND "PLUMBING"

209-210 FT-DISTANCE IF MEASURED ALONG THE GROUND —

STA. 12 + 00-^

FIGURE I.I BREÄKfNG CHAIN

Spikes (20d or larger) may be substituted for chaining pins.

Many times the chaining pins are not provided, but the spikes

are available or can be readily obtained. A substitute for a

chaining pin may also be made from No. 9 galvanized vire.

Regardless of the type of pin the procedure is the same and for

purposes of explanation it will be assximed that spikes are used.

When chaining is begun he counts out 11 spikes, sticks one in

the ground to mark the starting or zero point and puts 10 in a

convenient pocket emptied of all other objects. When the first

station is lined in and measurement completed the head chainman

sticks a spike in the ground at that point and calls or signals

to the rear chainman that measurement is completed. The rear

chainman then pulls the spike at his location and puts it in one

of his pickets that is free from all other objects, then moves

forward to the next station at the same time the head chainman

is moving forward in readiness for setting the next station.

This process is continued until the head chainman uses his last

spike. At this station Í0 spikes have been used and 1,000 feet

has been measured. The head chainman calls "spike" to rear

chainman, at which time the rear chainman moves up and delivers
1-5

his collected 10 spikes to the head chainman. The head chainman

then records station 10+00 in his notebook. This process is continued until measurement of the line in question is completed.

Suppose that measurement was completed when the head chainman

had k spikes left and station 20+00 had been recorded in his

notebook. This would mean that 10 minus ^ or 6 spikes had been

used ahead of station 20+00 and that the station at the end of

the line would be 26+00.

c. Stadia method for measuring horizontal distances requires the

use of a transit or level equipped with stadia hairs. There are

three horizontal cross hairs and one vertical cross hair in this

arrangement. The horizontal cross hairs are so spaced that any

intercept between the top and bottom cross hairs when read on a

graduated rod such as a level rod or stadia rod, if multiplied

by 100, will give the distance between the instrument and the

rod. The use of stadia will have little application generally

by soil conservationists and will not be discussed further in

this handbook. It will be most useful where a large amount of

detailed topographic mapping is necessary. In such situations

it may be necessary to obtain the services of an engineer to

train soil conservationists in applying this method.

1.22 Equipment for Chaining

a. Steel tapes are made of flat steel bands marked in various

ways (Figure 1.2). The markings may be etched, stamped on

clamps or soldered sleeves, or stamped on bosses. Steel tapes

may be obtained in lengths up to 500 feet, although the most

commonly used is 100 feet long. Tapes are usually marked at

one foot intervals, except the first and last foot, which is

generally graduated in tenths and hundredths.

Z2

RIVETED TABS

H:a c^

n

BABBITT METAL BOSSES

ETCHED

(ILLUSTRATIONS COURTESY KÖE CO.)

FIGURE 1.2 STEEL TAPE MARKINGS

Some tapes may have an extra foot at one or both ends marked in

tenths and hundredths. Tapes marked in feet, inches, and

eighths are usually furnished in a leather case and are lightweight steel ribbons as compared with the heavy duty field
1-6

engineer's tape. Because of the wide variety in manner of marking

tapes whenever a tape is used for the first time^ the surveyor

should inspect it carefully to determine how it is marked.

Tapes using clamped or soldered sleeves for foot markings are

commonly used without reels because of their bulkiness when

rolled on a reel. Tapes without reels are done up in a figureof-eight and then "thrown" into a circular shapel. The method of

"throwing" a tape does not lend itself well to a\ written

description. Hence, the surveyor should learn ttliis procedure

from an experienced siirveyor,

b. Metallic or woven tapes are made of cloth with fine brass

wire woven into them to minimize stretching. They usually come

in lengths of 50 feet but may be 25 feet or 100 jfeet long. They

are used for measxirements not requiring a high q.egree of accuracy

such as securing dimensions of existing bridge ¿penings, measurement of short distances in taking cross sections or topography,

measuring distances for strip cropping layouts,I orchard terracing layouts, etc.

1.23 Minor Repairs and Care of Tapes

a. Steel tapes are easily broken if not properly handled. Do

not jerk the tape needlessly. Do not step on it or allow vehicles to run over it and do not attempt to bend it around sharp

corners. The most common cause of a broken tape is pulling or

jerking on it when there is a loop or kink. Slight deformations

caused by kinking should be carefully straightened with the

fingers.

b. In spite of reasonable care, tapes will occasionally be

broken. Each headquarters having an engineer regularly assigned

should have a tape repair kit. Repairs should be made under the

supervision of an engineer.

c. After each day's use, steel and metallic tapes should be

wiped clean and dry with a clean cloth. Steel tapes should be

given a light coating of machine oil by wiping with an oily cloth

after cleaning. If rust spots are formed during a day's use in

wet weather, the tape may be cleaned with wood ashes or a

kitchen cleanser. Do not use a coarse abrasive such as sandpaper or emery paper. This will eradicate the markings on the

tape.

d. The cost to the Government of a steel tape is about 10 to 15

dollars, depending upon whether a reel is included. The average

cost of a metallic tape is about five dollars. The value of this

equipment merits good care. In any event, good work can never be

done with tools in poor condition. A good workman takes pride

in the good condition of the tools he uses.
1-7

1.30 DIFFERENTIAL LEVELING

1.31 General

Planning and establishment of all mechanical practices used in

soil and water conservation work require information regarding

the relative elevation of points on the earth's surface. For

example^ water will flow from one point to another in a terrace

channel only if there is a difference in elevation between the

two points. Among other factors^ we must know what the difference is in elevation in order to determine how fast the water

will flow between the points. Various methods may be used to

determine relative elevations^ the method selected depending

upon the type of work for which the elevations are required.

a. For very accurate work it is necessary to take into account

the fact that the earth's surface is spheroidal. Points of

equal elevation do not actually lie in a plane but on a spherical surface - that is^ points of equal elevation are points

which are equal distances from the center of gravity of the

earth. In very precise leveling work the curvature of the

earth is taken into account. For most soil conservation work,

however, this factor may be disregarded. Most leveling work

performed by soil conservationists will be considered as "thirdorder" leveling, in which the permissible "error of closure" in

feet can be obtained by multiplying O.O5 by the square root of

the length of the circuit in miles. Stated as a formula; permissible error (ft.) =0.05 VM" (where M is the length of

circuit in miles).

b. Tnree principal methods are used' in detennining differences

in elevation: Barometric, trigonometric, and differential (or

spirit) leveling. Differential leveling is the method most

commonly used and is the only one on which procediires will be

explained. It utilizes the phenomenon that a spirit level can

be used to fix a line of sight perpendicular to the action of

gravity - that is, a perpendicular line extending from the

spirit level to the center of gravity of the earth. This line

of sight can then be used to determine differences in elevation

between nearby points on the earth's siorface.

1.32 Kinds of Levels and Functioning

a. The four types of levels commonly used include the engineer's

wye and dumpy levels, and the two hand levels, the Locke and the

Abney.

b. The dimapy level. Figure 1.3, because of its sturdiness,

convenience, âfid stability of adjustment, has largely superseded

the wye level. The telescope on the d\mipy level is rigidly

attached to the frame.

c. The wye level (Figure l.k) is so-called because the telescope rests in Y-shaped supports and can easily be removed.
1-8

OBJECTIVE CROSS HAIR RING

CAPSTON HEAD SCREWS

EYEPIECE

OBJECTIVE LENS CAP

(ILLUSTRATION COURTESY KSE CO.)

FIGURE 1.3 ENGINEER'S DUMPY LEVEL

WYE CLIP NOTE: OTHER NOMENCLATURE SAME AS FOR DUMPY LEVEL

WYE ADJUSTING

WYE SUPPORT

(ILLUSTRATION COURTESY KSE CO.)

FIGURE 1.4 ENGINEER'S WYE LEVEL
1-9.

d. The Locke hand level (Figure 1.5) is used for rough measurements of differences in elevation. It is used by merely standing

'SPIRIT LEVEL ^TUBE

ADJUSTING SCREWS JlFtf^^^^^HHlHHHHMHHHli^ ^ .EYEPIECE

(SLIDING OR FIXED)

(ILLUSTRATION COURTESY K 8 E CO.)

FIGURE L5 LOCKE HAND LEVEL

erect and sighting through the eyepiece, holding the tube in the

hand, and moving the objective end up or down until the image of

the spirit level bubble on the mirror is centered on the fixed

crossed wire. The point where the line of sight in this position

strikes the rod or other object is then noted. A rough line of

levels may be carried with the hand level for a distance of ^i-OO

or 500 feet, provided the length of each sight is not over about

50 feet.

Slopes can be measured by use of the Locke hand level by the

following procedure:

Step 1. Determine the height (H) of your eye above the ground

at your feet when standing erect. This height can be

determined by direct measurement or approximately by

subtracting four-tenths (0.4) of a foot from your

height. For example, assimie (H) = 5.3 feet.

Step 2. Stand erect, face toward the slope along a given line,

and sight the hand level with bubble level on an

easily distinguishable object on the surface of the

ground.

Step 3. Pace the distance from the point occupied in Step 2

along the given line to the object observed in Step 2.

Let us assume this paced distance is 60 feet.

Step 4. Determine the vertical rise per 100 feet. This is

obtained by multiplying the eye height (H) by 100 and

dividing by the slope distance paced.

5.3 X 100 = 8.8 ft. vertical rise per 100 ft. or 8.8^

60

e. The Abney hand level (Figure 1.6) is constructed and f\mctions in the same manner as the Locke hand level, except that it

is equipped with a graduated arc for reading percent of slope.

The spirit level is attached to the arc on the Abney level. The

user sights through the tube and fixes the line of sight so that

it will be parallel to the slope on which it is desired to

measure the percent of slope. The indicator is then adjusted
1-10

SPIRIT LEVEL

CAPSTAN HEAD ADJUSTING SCREWS

INDICATOR ARM

EYEPIECE

SLIDING OR FIXED)

CLAMP Ai?C X^^CAPSTAN HEAD ADJUSTING SCREWS

(ILLUSTRATION COURTESY KSE CO.)

FIGURE 1.6 ABNEY HAND LEVEL

with the left hand until the image of the spirit level bubble is

centered on the cross wire. The indicator is then clamped and

the percent of slope read. It may be used in the same manner as

the Locke hand level for running.a level line if the indicator

is clamped at the zero reading.

f. Both types of hand levels may be equipped with a sliding

eyepiece. When the sliding eyepiece is extended, it has the

effect of lengthening the line of sight within the tube^ thus

increasing the accuracy of observations.

1.33 Level Eods and Accessories

a. There are many different kinds of level rods. The types

standardized for general use in this Eegion, Figure 1.7^ are as

follows :

(1) The Philadelphia type rod is a two-section rod equipped

with clamp screws. Its length is approximately seven feet

extending to 13 feet, and it is graduated in feet, tenths,

and hundredths. It may be equipped with round, oval, plain,

or vernier scale target.

(2) The Frisco or California type rod is a three-section

rod equipped with clamp screws. Its length is k^ feet

extending to 12 feet, and it is graduated in feet, tenths,

and hundredths. This rod is not equipped for use with a

target.

(3) Tne Chicago or Detroit type rod is a three-section rod

with metal telescoping joints. The length of each section

is approximately k^ feet extending to 12¿ feet. It is

graduated in feet, tenths, and hxmdredths, and is generally

not equipped for use with a target.

(k) The stadia rod is a two-piece 13-foot rod joined

together with hinges and with a suitable locking device to

insure stability, and is complete with metal shoes on both

ends. The face is approximately 3è inches wide, and is
1-11

divided into feet and tenths. This type of rod is designed

primarily for use in making topographic surveys and is not

equipped for use with a target.

f

RANGE

POLE

(ILLUSTRATIONS COURTESY EUGENE DIETZGEN CO. )

PHILADELPHIA

LEVEL ROD

FRISCO

or CALIFORNIA

LEVEL ROD

^HIIMGE

mm

(ILLUSTRATION COURTESY

FREDERICK POST CO.)

CHICAGO

or DETROIT

LEVEL ROD

STADIA

ROD

FIGURE 1.7 RANGE POLE AND SURVEYING RODS

b. A lightweight hatchet or hand ax should be carried by the

rodman to mark bench marks, for brushing out lines, and for use

as a solid turning point.

1.3^ Care and Handling of Surveying Instruments

a. General

Surveying instrijments are precise, delicate pieces of equipment

varying in price from $75 or $100 to several hundred dollars.

Their cost Justifies proper care and protection, and this is

necessary in order that the instruments will be kept in accurate

adjustment and operating condition for survey purposes. Certain

procedures and precautions must be observed in using surveying

instruments in order to prevent needless damage, unnecessary

wear, and to reduce occurrence of accidents. Instruments in

good condition, properly adjusted, are essential to speed and

accuracy of field work.
1-12

b. Transporting Instrimients

Surveying instriments generally are transported to the job by

automotive vehicle. The level should be carried in the instrument case^ in the cab of the vehicle, preferably on the seat.

It should be subject to as little vibration as possible. Level

rods should be in cases and carried where they will be protected

from weather and where they will not have other material piled

on top or against them. Tripods should be similarly protected

frcan damage and the weather.

--TRtPOO CAP

c. Mounting the Level on the Tripod

(1) The vehicle transporting the equipment to the field

carries it to a convenient location near the job. The level

is mounted on the tripod at this point and the survey equipment Is then carried to the field by the survey party.

(2) The first step in mounting the level is to set up the

tripod (Figure 1.8). The tripod cap should be removed and

placed in the instrument box to prevent it from being lost.

The wing nuts on the

tripod should be jr»^

tightened just enough %ss^^

so that when a tripod

leg is elevated it will ÄBP^-WiNG NUT

drop gradually of its

own weight.

(3) The level should be

carefully removed from

the instrument case. It

is better to place the

fingers beneath the horizontal bar in handling

the instrument. See

that the instrument is

securely attached to the

tripod. When screwing

the instrument base on

the tripod, it should

first be t\irned in the

reverse direction until

a slight jar is felt,

indicating that the

threads are properly

engaged. It should then

be screwed on slowly

until it refuses to turn

further, but not so

tightly engaged that it

will be difficult to

unscrew when the instrument is to be dismoimted. FIGURE 1.8 TRIPOO AND CAP

TRIPOD ' Â

LEG
1-13

(k) The object glass cap should be removed and placed in

the instmrnent case for safe keeping, and the sunshade

attached to the telescope. Always attach the sunshade,

regardless of weather.

d. Carrying the Instrument

(1) The instrument usually is carried to the field on the

shoulder. But in passing through doors, woods, or brush

hold the instr"ument head close to the front of the body.

Little damage will be done if the tripod legs strike the

side of a door Jamb or tree but to allow the level to strike

against an object is an "unpardonable sin."

(2) Before crossing a fence, reach across and set the

instrument on the opposite side with the tripod legs well

spread out. Do not allow the instrument to fall.

e. Setting Up Instrument For Field Use

(1) When setting up the instrument in the field, bring the

tripod legs to a firm bearing with the foot plate approximately level. Give the tripod legs additional spread in

windy weather or in places where the instrijment may be subject to vibration or other disturbances. Most tripod shoes

are usually provided with a projection which the surveyor

can step on to force the tripod shoe firmly into the ground.

When setting up on a side hill, place two tripod legs at

approximately the same elevation downhill and place the

other leg uphill, well extended, so that the foot plate

will be approximately level.

(2) In leveling the instrument much needless turning of the

leveling screws can be avoided if the tripod is always set

up so that the foot plate is nearly horizontal. The leveling screws should be brought to a snug bearing. If they are

too loose, the instrument will rock, causing inaccurate

readings. If the screws are too tight, the threads may be

stripped or the head and frame may be permanently damaged.

f. Precautions and Suggestions in Operating Instruments

(1) From the very beginning cultivate the habit of delicate

manipulation of the instrument, Eough and careless handling

of field instruments is characteristic of the unskilled

surveyor.

(2) Eyepiece. Before beginning observations, the eyepiece

must be perfectly focused on the cross hairs. The cross

hairs may appear sharp and distinct when the telescope is

focused on a distant object, but will move about or appear

to Jump if the eye is shifted slightly. On the other hand,

the telescope may be focused on a distant object, and the

cross hairs will not be visible at all. These two
H4

conditions are known as parallax. In normal operation^ the

eyepiece should be checked for parallax before beginning

observations for the day and should be checked several

times during the day if the instrument shows a tendency to

easily develop parallax. The adjustment is made as follows:

Focus the telescope as clearly as possible on a well defined

object about 300 feet away. Then hold a sheet of the field

book about one foot in front of the objective^ and move the

eyepiece in or out \mtil the cross hairs appear sharp and

distinct against the white backgroimd of the field book

page. Then re-focus the telescope and observe whether the

cross hairs move or jijmp when the eye is shifted slightly.

Eepeat this process until the cross hairs do not appear to

move when the eye is shifted and a clear sharp image of the

distant object appears. To obtain focusing true for natural

vision, the eye should be closed several times between

observations to allow the lenses of the eye to assume their

natural condition. If this is not done, especially by yoimg

men, the eye may accommodate itself to the telescope rather

than the telescope becoming adjusted to the eye.

(3) Do not tighten clamps too tightly. The ears of clamps

and wing nuts are purposely made small, so that it is difficult to turn them too tightly. By experience, learn just

how much to tighten the clamps to prevent slipping,

(k) Guarding instrument. NEVEE LEAVE AN INSTRUMENT

UNGUAEDED IN THE FIELD. If damage results in such cases an

employee may be held pecuniarily responsible.

(5) Exposure of instruments. Instrijment cases usually are

provided with a waterproof cover. In threatening weather

this bag should be carried to the field and placed over the

instrument if it rains. If the instriament becomes wet or

dusty, it should be properly cleaned the same day.

g. Storage of Equipment

(1) Always return the instriament to the case when returning

from the field. NEVEE ATTEMPT TO TEANSPOET AN INSTEIMENT IN

A VEHICLE mm IT IS MOUNTED ON THE TEIPOD. In placing the

level into the case the lid should close freely and easily.

If it does not, the instrument is not properly placed on the

pads. Never force the lid; look for the cause of the

obstruction. Before placing the instrument in the case

replace the object glass cap on the telescope and return the

sunshade to the case.

(2) Tripod cap (Figure 1.8). The tripod cap should always be

placed on the tripod head when the tripod is not'in use.

The tripod head threads as well as the instrument foot plate

threads are of brass which can be easily damaged if struck

against a hard object. Inspect the tripod legs and shoes

and remove any mud or dirt that may have accumulated in
1-15

field use. The leather strap at the foot of the tripod

should always be secured when the tripod legs are closed and

the tripod is not being used. This is to prevent undue

strain on the pins connecting the legs to the tripod head.

(3) Equipment should be stored in a dry place. Level rods^

stadia rods^ and tripods must be stored in such a manner that

they will not warp or become otherwise damaged. They should

be fully protected from the elements when not in use. It is

better to store level rods flat on at least three supports.

Never leave a rod leaning against a wall for long periods.

They warp from their own weight. It is satisfactory to store

them in a plumb position. A coat of varnish should be

maintained on the wooden parts at all times.

h. Cleaning and Inspection of Instrimient

(1) In setting up the instrument indoors for inspection or

cleaning be careful that the tripod does not spread, dropping

the instrument on the floor. Spreading of the legs can be

prevented by setting the tripod shoes in holes or cracks in

the floor or by tying a cord around and through the openings

in the legs so they cannot spread. NEVER LEAVE AN INSTRUMENT STANDING IN A ROCM UNGUARDED.

(2) Cleaning metal parts. Dust and grime which collects on

the outside moving parts must be carefully removed from

surveying instruments. A light machine oil may be vised for

softening grime on leveling screws, foot plate threads,

clamp screws, and other outside parts which may be cleaned

without dismantling the instrument. A drop of oil may be

placed on a leveling screw which may then be screwed back

and forth to bring out dirt and grime, wiping it off with a

clean cloth until the oil comes through clean. It is better

not to leave any oil on the instrument. It does not need

any lubrication. The oil merely catches and holds dust

which abrades the soft brass parts.

(3) Cleaning lenses. Do not remove or rub the lenses of

the telescope. These lenses are made of soft glass which

scratches easily. They should be dusted with a clean, soft,

camelas hair brush, or wiped very carefully with a clean,

soft cloth to avoid scratching or marring the polished

surfaces,

(k) Beginners should not disturb the capstan head adjusting

screws except under the supervision of an engineering specialist. Also, if any screw or other part works harshly,

call such defects to the attention of an engineering specialist. If repairs or adjustments cannot be made by the

engineering specialist send the instrument to the factory

for repairs in accordance with established administrative

procedures.

259293 O - 53 - 2
1-15

1.35 Hand Signals

a. In order to transmit information between the observer or

instrimient man and his rodman^ the maximum use should be made of

hand signals. Any code of signals mutually understood by the

instrument man and the rodman is good if it works. The instrument man should be prompt in signalling the rodman when he is

finished with the "shot" so that the rodman can move off promptly

to the next point.

b. The code of signals illustrated in Figure 1.9 is suggested.

This code may be enlarged upon or altered to suit the needs of

the job. A definite code should, however, be determined and

mutually understood in order to speed up the Job.

1.36 Bench Level Circuit

a. The procedure and field notes used in running a bench level

circuit may be considered as the basic system for all differential leveling work. The beginner should be thoroughly familiar

with this basic system. A bench level circuit is run for the

pu3rpose of detennining the relative elevations of two or more

bench marks. The circuit may start from a highway or USGS bench

mark or from some point of assumed elevation. A bench level

circuit is frequently run as a part of profile or cross section

levels or as a part of a topographic survey. The basic procedure and notes will be the same in any event.

b. On the larger drainage projects it is desirable to run the

bench level circuit separately from all the other survey work.

If this is not done, and mistakes occur, a great deal of additional work will be required to carry corrections through the

survey notes. BENCH LEVELS SHOULD ALWAYS BE "CLOSED" ON THE

STAETING POINT. That is, after the last bench mark is set,

levels should be run back to the starting point as described in

Paragraph 1.36 d (6).

c. Definition of Terms

Eeferring to Figure 1.10 (page l-l8) and Figure 1.11 (page 1-19),

the common tenas used in leveling are as follows:

A BENCH MABK (BM) is a point of known elevation of a permanent

nature. Such points may be marked with a brass pin or cap set in

concrete, a cross or square mark cut on concrete, a long metal

stake driven into the ground, a specifically located point on a

concrete bridge, culvert, or foundation, or similar objects which

are not likely to be disturbed for a long time. Temporary bench

marks are points of known or established elevation which will be

useful for only a few weeks and may be subject to disturbance if

left longer. Such bench marks may be established on wood stakes

set near a construction project or on nails driven into trees.
1-17

Move in this direction Move in this direction Plumb rod Plumb rod Turning point

Use long rod Observation completed

or Move on

or Understood

Wrong-face

or Check clomp

or Rod upside down

Move down

Move up Turning point

( by rod man )

Wove rod slowly

from side to side

Come in

FIGURE 1.9 CODE OF HAND SIGNALS
1-18

EL. 144.62

FIGURE 1.10 METHOD-DIFFERENTIAL LEVELING

A TUENING POINT (TP) is a point on which the elevation is determined in the process of leveling, but which is no longer needed

after necessary observations have been taken. A turning point

should be located on a firm object, whose elevation will not

change during the process of moving the instrument set-up. A

small stone, fence post, or the head of a hand ax driven into

the ground is usually satisfactory for this purpose.

A BACKSIGHT (BS) is a rod reading taken on a point of known elevation. It is the first reading taken on a bench mark or turning point immediately after the initial or a new set-up. The

backsight rod reading added to the elevation of the point on

which the rod was held gives the height of the instrument.

A FORESIGHT (FS) is a rod reading taken on any point on which

the elevation is to be determined. Only one backsight is taken

during each set-up; all others are foresights.

HEIGHT OF INSTRUMENT (HI) is the elevation of the line of sight.

It is determined by adding the backsight rod reading to the

known elevation of the point on which the backsight is taken.

d. Procedure

(1) The level is set up at some convenient point between

the starting bench mark and the next bench mark or turning

point, but usually not over 300 feet from the starting bench

mark. It is difficult to read the level rod at distances

over 300 feet. A little practice will reveal what should be

the limiting distance for the particular level being used.

(2) The instrument man begins his field notes by recording

the following information (Figure 1.11, page 1-19):

(a) Location of survey, including name of farm or

farmer and legal description of quarter-quarter section

in which the starting point of the survey is located.
1-19

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TPô 4 93 /49.24 522 /44 3/

BM/ 4.60 /4464

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FIGURE l.ll SURVEY NOTES-DIFFERENTIAL LEVELING

(b) Type of survey such as "bench level circuit,"

"cross sections," or similar description.

(c) ColuQin headings on left-hand sheet.

(d) Names of surveyors.

(e) Date of survey.

(f) Description of starting bench mark. Include reference to the field book in which the elevation of the

bench mark was originally recorded. If it is a new bench

mark with an assumed elevation, no such notation need be

made; however, this assumed elevation should be in even

feet, as 100.00 or 200.00 feet,

(3) With the rodman holding the rod on the bench mark, the

instrument man observes the rod reading and records it in

the backsight column opposite the station (Sta.) EM 1.

Eeferring to Figures 1.10 and 1.11 it will be noted that the

backsight on BM 1 was 6.82 feet. This reading, added to

144.62 (elevation of BM 1), recorded in beginning the field

notes, gives 151.44, the HI, or elevation of the line of

sight.
1-20

(h) The rodman then moves ahead and picks out a convenient

point for a turning point, or drives his hand ax into the

ground for this purpose. The instrument man turns the telescope and takes a rod reading on this turning point. He

records this reading in the foresight (FS) column opposite

turning point (TP) 1. In Figures 1.10 and 1.11 the foresight for TP 1 -was 5.1? feet. This reading subtracted from

the HI^ 151.^-^, gives 146.27^ the elevation of the turning

point.

(5) The instrument man then picks up the level^ moves

ahead^ and goes through a process similar to that described

above, taking a backsight on TP 1^ and a foresight on a new

turning point ahead.

(6) After the elevation of the last bench mark has been

determined, the survey party runs levels back to the starting bench mark in order to "close" the circuit. Referring

to Figure 1.11, it will be noted that the foresight on M 3^

the last M in the circuit, was 3.6^, giving an elevation of

155.3^ for BM 3. It will also be noted that the backsight

on BM 3 "was 3.02 feet. This indicates that after taking the

foresight on BM 3 aiid computing the elevation, the level was

pulled up and re-set in a different place. The level should

always be pulled up and re-set before starting to run the

closing levels back to the starting bench mark. Levels are

then run back to the starting bench mark following the same

procedure used in running out the original circuit. Note

that in a bench level circuit BENCH MARKS SHOULD ALWAYS BE

USED AS A TURNING POINT,

(7) After taking the final foresight on the starting bench

mark, the "error of closure" can be determined. This is the

difference between the actual elevation of the bench mark

and the elevation computed from the final foresight. Referring to Figure 1.11, it will be noted that the elevation computed from the'final foresight was 0.02 feet too high or

+0.02 feet. Length of circuit is approximately 0.5 mile.

To determine pennissible error use the formula given in

1.31a. Substituting we find permissible error = O.O5 V0.5

= 0,035. Actual error is 0.02 which is less than that permitted. Level note computations should be checked by adding

the backsight and foresight columns as shown in Figure 1.11.

The difference should equal the error of closure and should

be in the same direction - that is, plus or minus. This

check merely proves the accuracy of the addition and subtraction performed in the notes. If the foresights and

backsights do not check, it will be necessary to re-check

the computation of elevations and heights of instrument

until the mistake is found.
1-21

1.37 Profiles and cross sections

a. The object of profile leveling is to determine the elevations

of the ground at known distances apart and along a selected or

predetermined line. These elevations can then be plotted on profile paper at selected scales so that studies can be made relating to grades, depths, high and low spots, and estimating of

quantities of cuts and fills. Cross sections are simply profiles taken at right angles to a predetermined base line such as

the centerline of a road, ditch, gully, or other arbitrarily

selected base line. Cross sections may be run in conjunction

with profile levels, or they may be run after the profile line

has been staked and profiles taken.

b. Procedures

(1) The procedure in running a profile, and recording field

notes, is essentially the same as in r"unning bench levels,

except that ground rod readings are taken at full stations

and at major breaks in slope. Distances between readings are

measured and recorded by full or plus stations. Normally a

line on which a profile is to be run is located and stationed before profile levels are taken. It is also possible

and sometimes desirable to locate the line, station it out,

and take the profile levels in the same operation when a

party of three or more men is available.

(2) Wherever possible set a bench mark near the starting

point stake. If this cannot be done, it will be necessary

to run levels from the nearest bench mark to the starting

point. Location of the starting point stake is described in

the notes so that it can be re-located if it is pulled out

or otherwise lost. The start of the profile should be at a

full station. It may be 0+00 or any other selected full

station. It is frequently advisable to use a higher station

as 10+00 or 20+00 where it is anticipated that it may be

necessary to r^m the profile both ways from the starting

point. This is done in order to avoid having to record

minus stationing, which is always confusing. The sample

field survey notes. Figure 1.12 (page 1-22), illustrate the

use of a station other than 0+00 for the starting point. In

this case the survey party started at station 20+00, ran the

profile back to station 9+00, then started again at station

20+00 and ran the profile down to station 29+00.

(3) After establishing the starting point, the instrument

man sets up the level and reads a backsight on the bench

mark and determines the HI. He then observes a rod reading

with the rod held on the ground at the starting point. He

gives a ground rod reading at each full station and of such

plus stations as are necessary. Ground rod readings are

taken to the nearest 0.1 foot and ground elevations are computed only to the nearest 0.1 foot.
1-22

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FIGURE 1.12 PROFILE SURVEY NOTES
1-23

(k) When the rodman has moved along until he is about 300

to 350 feet away from the instriament, a TP is taken on a

solid object. The instrument man then moves ahead, sets up,

takes a backsight on the TP, computes a new HI, and continues

as before. Rod readings and elevations on TPs and Ms should

be read and recorded to 0.01 foot. HI elevations should be

determined to 0.01 foot but in computing ground elevations

use the HI only to the nearest 0.1 foot.

(5) A sketch should be kept on the right-hand page of the

field book to indicate changes in direction of the profile

line and its relationship to nearby landmarks. Plus stations should always be measured and recorded at all important points along the profile line, such as at branch

ditches, tile laterals, gullies, gully overfalls, culverts,

bridges, roads, fence lines, and similar features. It is

useful to have this information in studying the profile and

later in staking construction works on the ground.

(6) Frequently it will be desirable to set a hub stake

(2"x2"xl6" stake driven flush with the ground) every 5OO

feet or less in order to "tie in" or relate other survey

work to the profile.

(7) The sample survey notes (Figure 1.12) indicate the

method of recording cross-section notes when cross sections

are rim at the same time as the profile. A point is

selected along the profile line, for instance, station 23+00

as shown in Figure 1.12, at which it is desired to obtain a

cross section. The profile line is used as the base line

from which measurements are taken to both sides at right

angles to the profile line. A rod reading is taken on the

profile line at this point and recorded on the right-hand

page opposite the appropriate station. Since this reading

was taken on the profile or base line, it is recorded as

-p^ and recorded directly on the centerline of the rightH-.O

hand sheet of the field book. The rodman then moves out at

right angles to the base line to the first major break in

the cross section. The rear chainman stands at the centerline or base line, reads and calls off the distance from

this point to the rodmian. Instrument man reads the rod and

records distance and rod reading. The process is continued

until the cross section is run out as far as necessary in

one direction. The rodman then returns to the base line and

a similar process is repeated in the opposite direction.

Note that elevations along the cross-section line are not

computed in the field unless they will be plotted in the

field. Tnis work is usually done in the office.

(8) It is not essential that the zero of the cross, sections

be the centerline of the gully, ditch, or stream. In some

cases the profile line may be along the bank of a ditch. In

any case, the zero of the cross sections is on the base line.
1-24

It is essential that the instr\3inent man indicate in the field

notes the direction of the cross section in such a manner

that it will be clear to him or to a draftsman in the office.

On ditch, gully, or stream cross sections it is standard

practice to refer to "right" and "left" bank, when facing

downstream. Where a cross section is taken at a proposed

structure site it should be located so that this line may be

reproduced later if required. This can be done by setting a

hub stake at the zero point of the cross section and one or

more additional stakes on the cross section line 30 to 100

feet from the zero point. These stakes should be driven

nearly flush with the ground so they will not be disturbed.

(9) Cross sections taken at right angles to a gully, stream,

or other meandering watercourse, can only be used for studying the hydraulic characteristics of the watercourse. They

cannot be used to construct a topographic sketch. For topographic surveys see part l.to.

l.lfO TOPOGEAPHIC SURVEYS

l.ii-1 Purpose

The purpose of a topographic survey is to secure the necessary

data to produce a map or sketch representing three-dimensional

relations of a portion of the earth's surface. This map or

sketch will include contour lines, location of streams, bridges,

culverts, gullies, buildings, fences, ditches, land lines,

roads, or other features needed for detail planning or needed to

determine how a proposed plan will fit the features.

1.42 Methods of Topographic Surveying

Three methods of topographic surveying are used: The grid

system, plane table and alidade, and the transit and stadia.

The grid system is the most simple but generally requires more

time than either of the other two methods. The plane table and

alidade, and the transit and stadia methods involve the measurement and plotting of horizontal angles and distances and the

measurement of vertical angles which are used in computing elevations, whereas the grid system only requires skill in using a

level and tape. "Where a considerable amount of topographic

sketching is required, either the plane table and alidade, or

transit and stadia method should be adopted, and the personnel

should be trained in the use of this equipment where the need

arises. Ordinarily the grid system will be used because a

level and a tape are available in every field office, while

alidades and transits are not always available. Only the grid

system will be described in this handbook.
1-25

l.ií-3 Procedure For Making Topographic Surveys by the Grid Method

a. Obtaining topography by use of the grid system consists of

selecting and laying out a series of lines on the ground that

can be reproduced to scale on drawing paper. All topography^

including ground elevation, is then obtained in the field with

reference to these lines and later plotted on drawing paper.

Contour lines can be drawn in on the drawing by interpolating

between plotted ground elevations.

b. In any survey for a topographic sketch, a survey plan must

be determined in advance. The following factors should be considered:

(1) What ground features are conveniently located for use

as base lines?

(2) Can the base lines be reproduced on a drawing in their

true relationship to each other?

(3) How far apart shall grid lines be set?

(k) How close together will ground elevations need to be

taken?

(5) What is the most efficient procedure to use?

c. In planning the survey procedure it must be remembered that

rod readings for elevations cannot be read with accuracy over

approximately 300 feet with the ordinary level and level rod.

If a stadia rod is used, it can be read at a distance of 500 or

600 feet. Ordinarily there should not be over approximately 200

feet between any two adjacent shots for ground elevations. On

very flat uniform terrain this distance might be increased to

300 feet. These factors will help to determine how far apart

ground elevations should be taken.

d. In some instances it will be necessary to establish right

angles for making grid layouts. If the surveying instriiment does

not have a horizontal circle for turning off right angles, they

can be established by the 3-^-5 method. This method is based on

the Pythagorean Theorem, which states that the square of the

hypotenuse of a right triangle is equal to the sum of the squares

of the^two legs (Figure 1.13, page 1-26), A marker is set at

point "A" at which point it is desired to lay off the right

angle.

e. Example:

(1) A procedure for gridding a field is shown in Figure

1.14, page 1-27, with accompanying field notes in Figure 1.15,

page 1-28. It is assumed that a level with a horizontal

vernier is available for use in laying out right angles from

base lines and grid lines. This gridding procedure has the
1-26

BASE LINE

FIGURE 1.13 "3-4-5" METHOD OF LAYING OUT A RIGHT ANGLE

advantage over other systems in that a smaller number of

instrument set-ups are required for taking the levels. Also

the entire Job can be done with a two-man survey party at a

reasonable rate.

(2) A particular area is to be gridded for preparation of a

topographic map. Inspection of this area on aerial photo

showed that north line of area was the farm boundary, was

well defined, clear of brush, and would serve best as the

base line. Further inspection showed that the south field

boundary was parallel to the north boundary and that the

east and west sides diverged from the north to the south.

Scaling on the photo showed the north side to be about 950

feet long, the south side to be about II90 feet long, and

the east and the west sides to be about 1200 feet long each.

With this information it was decided that north and south

grid lines at 400 feet and 6OO feet from the northwest corner of the field should be staked. It is generally desirable

to establish such grid lines near center of field to be

gridded. By the same reasoning it was decided that east and

west grid lines at 6OO feet and 8OO feet respectively from

the base line should be staked. With this plan decided on

and roughed out on a work photo or sketched on a piece of

paper, the two-man survey party went to the field.

(3) First an on-site check was made to determine if this

gridding plan was workable. No trees, hills, or other

obstacles were noted that would prevent use of the plan. A

sketch of the field and grid plan, Figure 1.15, was made in

the^field notebook, A range pole was set in the northwest

corner of field at point A,2. This point was called A,2 so

that no minus coordinates would have to be used. Had it

been called A,0 or A,l the point at the southwest corner of

the field might be G, (O-l) or some other minus designation.

Distances of tóO feet and 6OO feet from A,2 were chained

off eastward along the base line and a range pole set at

A,6 and a stake set at A,8.

(k) The level was then set up over stake A,8, sighted on
1-27

Ran^e Pole

5pk, &( Washer in 5. root of 20' e/m tree rjear

ÑW, Cor of JVIM ié of A/W, ^ Sec. 3, T 21N, R. 3JE.

Base Line & R L.

Range Po/e

Sfaf<e

/O

-Range Po/e

FIGURE 1.14 METHOD OF TOPOGRAPHIC SURVEY BY GRIDDING
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1-29

range pole at A,2 and a 90 degree angle turned off, and a

range pole sighted in and set at point G,8. This established direction for grid line 8. Line 8 was then chained

off, beginning point A,8 and working toward range pole at

point G,8. Four foot high stakes were set at 200 foot intervals along the line. Rear chainman lined-in each stake byeye between succeeding stake and range pole at G,8. The distance between points F,8 and G,8 was found to be 190 feet,

and so noted on field book sketch.

(5) Next a distance of 200 feet was chained off along south

line from point G,8 to Gy6 and a stake set at G,6. Line 6

was then staked, starting at point G,6 chaining off I90 feet

and lining stake between G,6 and range pole previously set at

A,6 at other end of field. Staking of line 6 was continued

at 200 foot intervals to range pole at A,6. This completes

lines 6 and 8.

(6) Grid lines D and E were staked next. Level was set up

over point D,8 and a 90 degree angle turned off from line 8.

Four foot high stakes were set at 200 foot intervals, starting measurement from level at point D,8 and staking to east

field boundary, then returning and staking to west field

boundary. Line E was staked in a similar manner.

(7) With the four grid lines staked, the elevation shots for

entire field can be completed without further use of tape

and with a minimum of pacing measurements, simply by locating

any other points by lining in by eye from the N & S and

E & W stakes. Obviously the grid line stakes must be distinguishable for several hundred feet. A field up to 60

acres in area can be gridded with a four line layout such as

this. A three-man party can lay out and stake these lines

in less time than it takes two men but probably not as

efficiently. A pick-up truck or other type motor vehicle

can be used to advantage in setting of range poles and distributing stakes when crops and other field conditions will

permit. Survey notes. Figure 1.15, illustrates a commonly

used method of keeping notes for this type of survey. Note

the intermediate shots that are not on regular grid points.

Most all gridding will require some intermediate shots to

locate and get elevations in low spots, high spots, existing

ditches, etc.

1.50 JOB LAYOUT

1.51 Purpose

The purpose of job layout is to transmit information from engineering plans to the job site or ground that will locate the

works and provide such lines, grades, and elevations needed for

construction of the job. This procedure is commonly called

staking a job for construction. Generally it requires the use

of surveying instruments. All engineering works require job

layout for construction.
1-30

1.52 Procedures

a. Layout procedures will vary with the type, size, and complexity of a job. For example, layout for contouring is generally done by pacing distances and setting line and grade stakes

with the aid of a hand level; whereas, layout for construction

of a structure will require relocation of survey lines, and setting centerline and elevation stakes. This must be carefully

done with a transit or engineer level and measurements accurately made with a steel tape

b. Layout procedure for a job will also be dependent to some

extent on construction methods and types of equipment used. A

layout man should contact the person or contractor that is to do

the construction, to discuss detailed layout. An agreement on a

layout procedure should be reached before any construction

stakes are set. Some experienced contractors will need but few

main stakes to build a job; on the other hand, some contractors

will need stakes for all details.

c. Setting slope stakes.

(1) Setting slope stakes for earth fill, ditch construction,

and most all other types of jobs that involve earthwork, is

part of a layout procedure that is widely used. Following

is an example of setting slope stakes for farm pond earth

fill construction. This procedure can be adapted for use

in setting slope stakes for open ditch, side spillway, and

any other earth work that requires placing or excavating

earth on a predetermined slope.

(2) Assume that an earth fill is to be staked and that the

following information is given: (Figure l.l6, page 1-31)

Top width of fill - 8 ft.

Upstream fill side slope - 3:1

Downstream fill side slope - 2:1

Elevation top of settled fill - 102.0

Location and elevation of B.M. - As determined

Fill centerline previously marked with appropriate stakes

(3) The following steps describe the procedure:

(a) Run levels from B.M. to a convenient point at the

fill site. The last HI must be above elevation of top

of fill before proceeding with slope stake setting.

(b) Compute difference between elevation of HI and top

of fill. Start staking at end of fill opposite emergency

or auxiliary spillway.
1-31

8' _j Width top of fill

Elev. top of fill 102.00

Upstream Downstream

'4' 4' I J ^ ^ I

^^^^/^^//^/////yyy//////////////////////////.y^^^^

Sta.O+OO

Sta.0+00-

V7777Z

^Centerline of fill

A. Cross Section Perpendicular to (g^fill

Slope stakes (3'l)

Upstream

C. Location of Slope Stakes

FIGURE 1.16 METHOD OF SETTING SLOPE STAKES

259293 O - 53 - 3
1-32

(c) Move the level rod up or down the hillside along

centerline of fill until a point is found where the rod

reading is the same as computed in (2) above. This

locates the end of fill. Set a stake at this point and

mark it 0+00.

(d) Set a stake at each side of station 0+00 at right

angles to centerline of fill at a distance of k feet.

These stakes mark the top width of fill and serve as

slope stakes at this point.

(e) Measure distances from station 0+00 down the hillside and along centerline of fill to points of obvious

breaks in ground slope as at 0+2^, O+56, etc, in Figures

1.16 (page I-3I) and I.I7 (page 1-33). Set temporary

stakes at these points and mark the stationing on them.

(f) Take a rod reading at the first stake (0+2Í]- in

example) on centerline of fill. Eecord reading. Set

upstream slope stake first (3:1 slope). The rod reading is found to be 7.3. Compute elevation of ground^

lOi^.7 - 7.3 :, 97.i|.. Compute fill height, 102.0 - 9?.^

= k.6 feet.

(g) For the first trial, measure a distance at right

angles to centerline stake of 3x k.6 -¥ k = I3.8 + k

= 17.8 feet (use I8 feet). Take a rod reading at this

point. In example the reading is found to be 7.0.

Compute ground elevation at the I8 foot point, 104.7 -

7.0 = 97.7. Compute fill height, 102.0 - 97.7 = 4.3

feet. Compute distance slope stake should be out for

this fill height, k.3 X 3 + 4 = 12.9 + ^ = l6.9 feet

(use 17 feet). But this point is actually I8 feet out,

so move the rod back toward centerline 1 foot so that

it is 17 feet from centerline and take another rod

reading. In example this reading was found to be 7.0;

thus, the last computation will hold and the slope stake

is set at 17 feet from centerline. Eecord the distance,

rod reading, and elevation.

(h) This or any other process is a cut-and-try method.

A little practice will develop judgment in how to make

these distance adjustments so that a minimum of time

will be required to find the location for the slope

stake. The same procedure is used to set the downstream

stake at station ö+2k, Eemember to use two times fill

height plus half the fill top width for downstream

slope stake location. After the two stakes are set at

station 0+2^1-, the same procedure is used to set the

remainder of slope stakes. Study Figure I.I6, page

1-31, and field notes Figure 1.17/ page 1-33, in order

to follow throTigh on the complete job of fill staking.

Staking of spillways usually follows fill staking.
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1.53 Determination of Earth Quantities

a. Most engineering jobs involving earth moving require that the

quantities placed or excavated be determined. Earth quantities

are used in estimating of costs of a job during planning stages

and as an item of work in taking bids and making subsequent payment for completed earth work.

b. Quantity determinations will be made by use of the end area

method for computing earth fill and earth excavation. This

method assumes that the volume between two successive cross sections is equal to the average of their end areas multiplied by

the distance between them. Expressed as a formula,

V = 1 X

Al + A2

V is the volume in cubic feet, Ai and A2 are the end areas of the

respective cross sections in sequare feet, and 1 is the distance

between the two cross sections in feet. But earth quantities

are to be expressed in cubic yards, thus the volume computed by

the above formula will be divided by 27.

c. Tables have been developed to assist with the application of

the end area method to earth problems.

(1) Earth dams - In computing yardage for an earthfill a

tabular foim should be used to record the information as

shown below.

station

(1)

Fin

Height

Ft.

(2)

Cu. Yds.

Per Ft.

(3)

Average

Fill

Cu. Yds.

Distance

Ft.

(5)

Fill

Cu. Yds.

(6)

0+00 0.0 0

1.7 2k ii-0 8

0+21^ k.e 3A

^.6 32 147.2

0+56 G.G 5.9

10.9 16 Yjk.k

0+72 11.6 15.9

li^.8 16 236.8

0+88 10.7 13.8

9.9 2k 237..6

1+12 6.8 6.1

5.0 16 80 0

1+28 5.2 h.O

2.0 60 1?0 0

1+88 0.0 0

A^C\J . w

Total volume of fii:L 1036.8

First run an accurate cross section along the centerline of

the proposed fill. Plot and divide it into segments, making

each break in ground line a division point as shown in
1-35

Figure 1.16, page 1-31. In coli;imn (l) record the station of

each break or division point. In coliomn (2) record the

centerline fill height at each division point. In column (3)

record the information obtained from the table Figure I.l8^

page I-36. Col-umn (k) record the average cubic yard figure

between the two successive stations. In column (5) record

the distance in feet between stations. In column (6) record

the product of {k) and (5). The sum of column (6) is the

total cubic yards of fill in the earth dam.

(2) Excavating open ditches. In computing yardage for an

open ditch a tabular form should be used to record the information. Cross sections of the proposed ditch should be

taken at regular intervals and at critical points. These

should be plotted on cross section paper and a planimeter

used to determine the end area in square feet at that point.

A tabular form to record the information is shown below.

station

(1)

End Area

Sq. Ft.

(2)

Sum of

End Areas

(3)

Cu. Yds. Per

100 Ft. Length

Distance in

Stations

100 Ft. Length

(5)

Cut

Cu. Yds.

(6)

8+00 32

9+00 5^ 86 159.3 1 159.3

10+00 62

10+3^^ 56 118 218.5 0.3^ 7^.3

In column (l) record the station of each cross section taken.

In column (2) record the end area in square feet of each

cross section. In column (3) record the sum of the end

areas between the two successive stations. In column {k)

record from the table on Figure 1.19^ page 1-37^ the amount

of cubic yards per 100 feet of length for the corresponding

STini of end areas. In column (5) record the distances in

stations between cross sections by 100 foot lengths; i.e.,

3^ feet =0.3^ for table. In column (6) record the product

of (k) and (5) . The siom of column (6) is the total cubic

yards in the excavation.
EARTH FILL YARDAGES

END AREA METHOD

ESTIMATE OF CU. YDS. OF FILL PER LIN. FT OF LENGTH IN EARTH DAMS WITH VARYING HEIGHTS AND TOP WIDTHS

FILL

HEIGHT

IN FEET

SLOPES 3 TO 1 AND 2 TO 1 SLOPES 3 TO 1 AND 2 TO 1 SLOPES 3 TO 1 AND 2 TO 1 SLOPES 3 TO 1 AND 2 TO 1

TOP WIDTH OF FILL-6 FEET TOP WIDTH OF FILL-8 FEET TOP WIDTH OF FILL-10 FEET TOP WIDTH OF FILL-12 FEET

.0 .1 .2 .3 .4 .5 .6 .7 .8 .9 .0 .1 .2 .3 .4 .5 .6 .7 .8 .9 .0 .1 .2 .3 4 .5 .6 .7 .8 .9 .0 .1 .2 .3 .4 .5 .6 .7 .8 .9

1 .3 .3 .4 .4 5 .5 .6 .6 .7 .7 .4 .5 .5 .6 .6 7 .8 .8 .9 .9 .5 .6 .6 7 7 .8 .9 .9 1.0 1.0 .5 .6 7 7 .8 .9 1.0 I.I I.I 1.2

2 .8 .9 .9 1.0 I.I I.I 1.2 1.3 1.4 1.4 1.0 I.I I.I 1.2 1.3 1.4 1.4 1.5 1.6 1.6 I.I 1.2 1.3 1.3 1.4 1.5 1.6 1.7 1.7 1.8 1.3 1.4 1.5 1.6 1.7 1.8 1.8 1.9 2.0 2.1

3 1.5 1.6 1.7 1.8 1.9 1.9 2.0 2.1 2.2 2.3 1.7 1.8 1.9 2.0 2.1 2.2 2.3 2.4 2.5 2.6 1.9 2.0 2.1 2.2 2.3 2.5 2.6 2.7 2.8 2.9 2.2 2.3 2.4 2.5 2.6 2.8 2.9 3.0 3.1 3.2

4 2.4 2.5 2.6 2.7 2.8 2.9 3.0 3.1 3.2 3.3 2.7 2.8 2.9 3.0 3.1 3.3 3.4 3.5 3.6 3.7 3.0 3.1 3.2 3.4 3.5 3.6 3.7 3.8 4.0 4.1 3.3 3.4 3.5 3.7 3.8 3.9 4.0 4.1 4.3 4.4

5 3.4 3.5 3.7 3.8 3.9 4.0 4.2 4.3 4.4 4.6 3.8 3.9 4.0 4.1 4.2 4.4 4.5 4.6 4.7 4.8 4.2 4.3 4.5 4.6 4.8 4.9 5.0 5.2 5.3 5.5 4.5 4.7 4.8 5.0 5.1 5.3 5.4 5.6 5.7 5.9

6 4.7 4.8 5.0 5.1 5.3 5.4 5.5 5.7 5.8 6.0 5.1 5.2 5.4 5.5 5.6 5.8 5.9 6.0 6.1 6.3 5.6 5.8 5.9 6.1 6.2 6.4 6.5 6.7 6.8 7.0 6.0 6.2 6.3 6.5 6.6 6.8 7.0 7.1 7.3 7.4

7 6.1 6.3 6.4 6.6 6.7 6.9 7.1 7.2 7.4 7.5 6.6 6.8 6.9 7.1 7.3 7.5 7.6 7.8 8.0 8.1 7.1 7.3 7.5 7.6 7.8 8.0 8.2 8.4 8.5 8.7 7.6 7.8 8.0 8.2 8.4 8.6 8.7 8.9 9.1 9.3

8 7.7 7.9 8.1 8.2 8.4 8.6 8.8 9.0 9îl 9.3 8.3 8.5 8.7 8.9 9.1 9.3 9.4 9.6 9.8 10.0 8.9 9.1 9.3 9.5 97 9.9 10.0 102 10.4 10.6 9.5 9.7 9.9 10.1 10.3 10.5 10.7 10.9 III 11.3

9 9.5 9.7 9.9 lO.I 10.3 10.5 10.7 10.9 II.1 11.3 I02 10.4 10.6 10.8 11.0 11.2 11.4 11.6 11.8 12.0 10.8 11.0 11.2 11.5 11.7 11.9 12.1 12.3 12.6 12.8 11.5 11.7 11.9 12.2 12.4 12.6 12.8 13.0 13.3 13.5

10 11.5 M.7 11.9 12.1 12.3 12.6 12.8 13.0 13.2 13.4 12.2 12.4 12.7 12.9 13.1 13.4 13.6 13.8 14.0 14.3 13.0 13.2 13.5 13.7 13.9 14.2 14.4 14.6 14.8 15.1 13.7 13.9 14.2 14.4 14.7 14.9 15.1 15.4 15.6 15.9

M 13.6 13.8 14.1 14.3 14.6 14.8 15.0 15.3 15.5 15.8 14.5 14.7 15.0 15.2 15.5 15.7 15.9 16.2 16.4 16.7 15.3 15.6 15.8 16.1 16.3 16.6 16.8 17.1 17.3 17.6 16.1 16.4 16.6 16.9 17.1 17.4 17.7 17.9 18.2 18.4

12 16.0 16.3 16.5 16.8 17.0 17.3 17.5 17.8 18.0 18.3 16.9 17.2 17.4 17.7 17.9 18.2 18.5 18.7 19.0 19.2 17.8 18.1 18.3 18.6 18.8 19.1 19.4 19.6 19.9 20.1 18.7 19.0 19.2 19.5 19.8 20.1 20.3 20.6 20.921.11

13 18.5 18.8 19.1 19.3 19.6 19.9 20.2 20.5 20.7 21.0 19.5 19.8 20.1 20.3 20.6 20.9 21.2 21.5 21.7 22.0 20.4 20.7 21.0 21.321.6 21.9 22.1 22.4 22.7 23.0 21.4 21.7 22.0 22.322.6 22.9 23.2 23.5 23.8 24.1

14 21.3 21.6 21.9 22.2 22.5 22.8 23.0 23.3 23.6 23.9 22.3 22.6 22.9 23.2 23.5 23.8 24.1 24.4 24.7 25.0 23.3 23.6 23.9 24.224.5 24.9 25.2 25.5 25.8 26.1 24.4 24.7 25.0 25.3 25.6 26.0 26.3 26.6 26.9 27.2

15 24.2 24.5 24.8 25.1 25.4 25.7 26.0 26.3 26.6 26.9 25.3 25.6 25.9 26.2 26.5 26.9 27.2 27.5 27.8 28.1 26.4 26.7 27.0 27.4 27.7 28.0 28.3 28.6 29.0 29.3 275 27.8 28.2 28.5 28.8 29.2 29.5 29.8 30.1 30.5

16 272 27.5 27.9 28.2 28.5 28.9 29.2 29.5 29.8 30.2 28.4 28.7 29.1 29.4 29.8 30.1 30.4 308 31.1 31.5 29.6 30.0 30.3 30.7 31.0 31.4 31.7 32.1 32.4 32.8 30.8 31.2 31.5 31.932.2 32.6 32.9 33.3 33.634.o|

17 . 30.5 30.9 31.2 31.6 31.9 32.3 32.6 33.0 33.3 33.7 31.8 32.2 32.5 32.9 33.2 33.6 33.9 34.3 34.6 35.0 33.1 33.533.8 34.2 34.534.9 35.2 35.6 35.9 36.3 34.3 34.7 35.0 35.4 35.8 36.2 36.5 36.9 37.3 37.6

18 34.0 34.4 34.7 35.1 35.4 35.8 36.2 36.5 36.9 37.2 35.3 35.7 36.1 36.4 36.8 37.2 37.6 38.0 38.3 38.7 36.6 37.0 37.3 37.7 38.1 38.5 38.8 39.2 39.6 39.9 38.0 38.4 38.8 39.2139.6 40.0 40.3140.7 41.1 41.5

19 37.6 38.0 38.4 38.8 39.2 39.6 39.9 40.3 40.7 41.1 39.1 39.5 39.9 40.3 40.7 41.1 41.4 41.8 42.2 42.6 403 40.7 41.1 41.541.9 42.442.8 43.2 43.6 44.0 41.9 42.3 42.743.1 43.5 43.944.3 44.7 45.1 45.5

20 41.5 41.9 42.3 42.7 43.1 43.5 43.9 44.3 44.7 45.1 43.0 43.4 43.8 44.2 44.6 45.0 45.4 45.8 46.2 46.6 44.4 44.8 45.2 45.7 46.1 46.5 46.9 47.3 47.8148.2 45.9 46.346.7 47.1 47.5 47.948.3 48.7 49.1 49.5

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

REGION UL

3-L-26923
0

1 1600 1700 1600 1500 IJlOO 1300 1200 1100 1000 900 800 700 600 500 1*00 300 200 100

0

0

0.0 il 972 918

m 810 756 702 6U8 591* 51,0 Ii36 1,32 378 32U 270 216 162 108 5U

0 0.0

1.9 97? 919 865 811 V>7 703 6Í0 ^5 *i i»87 U3Î 579 271 217 1^? 109 ^1

1 1.9

'•T 97Í 920 aá 812 758 70I, 650 596 ï42 .^88 ^i^ 380 526 272 218 1¿4 110

^

2 5-7 5-¿ 975 921 867 8I3 759 705 651 597 5U3 1*89 Íí35 J81 527 273 219 1¿^ 111 VÎ 3 5.6

7*k 976 922

m 8lli 7¿0 706 652 598 5Í.I, Up 1,36 382 328 271* 220 166 112 ^8

4 7.4

9.5 977 86? 8I5 761 707

^ •m 12 {í9i 1»^ 583

^ 221 167 11? 59

5 9-3

11.1

m 924 870 816m 708 6^ ¿00 î^ 1,38 381, 5^ 276 ??? 1Ó8 114 ¿0

6 11.1

15.0 979 ^5 871 817 7^? 709 655 601 {f9? 1»?? 551 277 223 1^ 115 61

7 13.0

1U.8 980 926 872 818 7äi 710 é5¿ 6«> Íi9t* 1(1(0 586 ??2 278 f^l 170 116 62

8 l4.8

lo.7 981 927 87? 819 765 711 ¿57 605 5li9 587 ^^? 279 225 171 117 ^?

9 16.7

18.5 982 928 87li 820 7éé 712 éçB ¿41550 \¿S M(2 388 í^ 280 226 172 118 ¿4 10 18,5

20.1i 985 929 Ö75 821 767 713

^^ ^1 Il97 %}

W 281 227 17? 119 ^5 11 20.1*

22.2

m 930 876 822 7é8m ¿¿0 ¿oë 5^ li98 Ik 390 336 282 228 174 120 ¿¿ 12 22.2

2i*.l 985 9^1 877 825 7Ä9 715 ¿61 6C7

^

IW Wi 591 va 283 229 175 121 ¿7 13 2i*.l

2^.9 986 952 878 82lf 770 716 662 608 500

U 592 338 28l* 230 176 122 68 11* 25.9

27.8 987 955 879 771 717 ^? 609 555 501 10,7 595 í?9 285 231 177 123 69 i 15 27.8

29.6 988 9^ 880 826 772 718 66!, 610 556 502 U,8 39Í* 3t,o 286 232 178 124 70 1 16 29.6

51.5 989 9^ 881 827 77? 719 ¿¿Ç 611

1 557 ^0? 1(1(9 'S»!! 287 233 179 71 i 17 31.5

990 9^ 882 828 77Í 720 6éé ¿12 'm 5Ï s^ 596 *2 288 234 180 126 72 18 33.3

35.2 991 957 885 829 775 721 667 613 599 1.51 ?97 31,3 2^ 181 127 73 19 35-2

57.0 992 958 881* 850 7Jé •/22 fAf\ 6li, 56a 506 1,52 598 314, 290 236 182 128 71* 20 37.0

58.9 995 9?? 885 831 777 7S 669 615 561 507 1,53

W íl(5 291 237 183 129 75 21 58-9

Ä0.7 99I1 9I1O 88¿ 852 778 72f| 670 ¿1¿ 562 508 U51, 1*00 Ä6 292 238 184 130 76 22 4o.7

l|2.ó 995 9hl 887 YW Y2h 671 ¿17 56? 509 ^55 jOl %^ 293 131 77 2? 1*2.6

hl}.k 99¿ 9^2 888 85ÍÍ 780 7a¿ 672 ¿18 glt 510 L56 402 5^8 294 2U0 186 132 78 24 l^.k

ié.^ 997 ^} 88? 855 781 727 ^^} ¿19 511

^ Î7 *05 31,9 2U1 187 133 79 46.3

1»8.1 998 9Öf 8^ 856 782 728 éiK ¿20 566 512 1,58

U 550 296 21,2 188 134 80 26 1*8.1

50.0 999 9te 891 «7 783 729 675 621 5¿7 515 U59 1*05 351 297 4? 189 81 27 50.0

^1-9 1000 9^ 8?2 838 781, 730 , 676 ¿22 ^¿8 514 tóo 1*06 552 298 2M» 190 136 82 28 51.9

^?.7 1001 9^7 ??? em 785 7?i 677 ??

^ ^15 i¿i U07 ?5? 299 191 i?7 Ö? 29 '?3-7

55.6 1002 9I48

m tifi 786 732 678 ¿2I, 570 516 1,¿2 1*08 ?% 300 21*6 192 138 84 30 5^5.6

vr^k 1005 9li9 aEi

m 733 ¿79 ^1 517

W I1O9 301 ^7 193 139 31 57.4

?9.5 lOQb 9^ ^6 ai,2 788 73U ¿80 626 772 518 lA 1*10 356 302 2i*8 194 ll*0 86 32 59.3

61.1 1005 9^1

W d,î 7W 735 681 ¿27 575 519 Í65 Í*ll 357 303 21*9 195 11*1 87 33 61.1

é5.0 1006 952 898 au» 790 736 6fP 628 57ÍI 520 1,66 1*12 358 304 250 196 11*2 88 31* 63.0

6L.8 1007 9^? 8?9 8L5 791 757 ^? 629 575 521

W í+1? 305 251 197 1+? 89 "í"? 6k.8

6¿.7 1008 9^ 900 8(16 792 738 68lt 630 57¿ 522

m ill* 360 30¿ 252 198 1+4 90 36 ¿¿.7

é8.5 1009 901 8Í7 793 739 ¿85 631 577 525 1(69 1*15 361 307 253 199 Ü*5 37 68.5

70.4 1010 956 902 81,8 79U 7U0 686 632 578 52í; 1,70 1*16 362 308 200 16 92 38 70.1*

72.2 1011 9^7 903 81,9 79^ 71,1 687 633 579 525 1(71 417 363 309 255 201

202

1*7 93 39 72.2

7i*.l 1012 9^ 90if 850 796 7i|2 688 63U 580 526 1,72 1*18 36i* 310 256 11*8 94 40 7a.

1

1015 959 90^ 851 WY 71,3 689 635 581 1,73 1*19 311 257 203 149 95 41 75.9

f/.O lOli* 9¿0 90e 8Ç2 798 7hh ¿90 636 582 528 l*7l» 1*20 366 312 258 204 150 96 42 77.8

79-é 1015 9él 90-/ 853 799 71*5 691 637 583 52? 1(75 1*21 367 313 151 97 43 79.6

81.^ 1016 962 908 800 7W 692 ¿38 581* 530 1,76 1,22 368 314 260 206 152 98 1*4 81.5

83.5 1017 963 909 855 801 71,7 ^5 6W 585 531 1,77 lf23 369 315 261 207 153 99 45 83.3

85.2 1018 96if 910 8Ç6 802 71,8 6?U ¿1,0 58¿ 532 1,78 h?h 370 316 262 208 154 100 46 85.2

87.0 1019 911 0^ 803 71)9 d,i 587 ííí k¡9 371 317 263 209 ipi 47 87.0

88.9 1020 966 912 838 8C¿ 750 696 6Í2 588 531, 1,80 UP¿ 372 3I6 26Í 210 156 102 48 88.9

90.7 1021 9é7 915 859 805 751 ¿97 61,3 589 535 Uei

h 373 319 265 211 157 103 49 90.7

^.6 1022 968 911^ 660 806 752 ¿98 614, 590 536 1,82 1,28 374 320 266 212 158 IQi* 50 92.6

?^-^ 1023 9é9 915 8él 807 753 ¿99 %, 591 557 1,83 1(29 375 321 267 213 159 105 51 94.4

9è.5 102U 970 9lé 862 808 75Í, 700 .(Á¿- 592 538 Ueu 1,30 376 322 268 211* 160 106 52 96.3

98.1 1025 971 917 863 809 755 701 61,7 993 539 1,85 1,31 377 323 269 215 161 107 53 98.1 0 1800 1700 1600 1500 11,00 1300 1200 1100 1000 900 800 700 600 500 1*00 300 200 100 0 0

AMOUNT OF CUBIC YARDS IN

100 FEET OF LENGTH FOR SUM

OF BND AREAS IN SQUARE FEET

Figures inside the double

lines are sum of end areas in

square feet.

Figures outside the double

lines are in cubic yards.

To find the cubic yards ina

100 foot length fora given sum of

end areas, locate this sum inside

the double lines, then read the

figure outside the double lines

at the top or bottom and add to

this the figure outside the double lines to the right or left.

EXAMPLE

An open ditch to be excavated has 52 sauare feet of

cross-sectional area to be removed at Sta. 8/00 and 5i*

square feet of cross-sectional

area to be removed at Sta.9/ 00.

Sum of end areas equals 86 square

feet. To find cubic yards of material to be excavated locate 86

square feet in body of table, read

100 at top of column plus 59.3 at

right, ora total of 159»3 cubic

yards to be excavated per 100

lineal feet.

At Sta. 10/ 00 the end area

is 62 square feet and at Sta.

10/ 3h the end area is 56 square

feet. Sum of end areas is 62/ 56

= 118 sq. ft. Locate 118 in body

of table, read 200 at top of column plus 18o5 at right or a total

of 200/ I8.5= 218.5 cu. yds.

per 100 feet. Sta. 10/ 00 to

10/ 3i*= 3I1 feet. Amount to be

excavated is equal tc 218.5 3C

O.3Í+= 7Í+.3 0X1, yds.

YARDAGE CHART BY SUM

OF END AREAS

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT. CHIEF

CARTOGRAPHIC APPROVAL.:

«AtWr. ^ifUla

DATE

5-49 3-N-I9I67

I
1-38

1.6o FIELD BOOKS

1.61 Purpose

Engineering field books are used for recording of original survey notes, and layout and construction data. This classifies

them as valuable documents because of the time and expense

involved in obtaining such data. An ordinary field book is worth

from $200 to $1000 when it is filled with notes properly recorded,

depending upon the type of surveys recorded. It seems only reasonable that a document of such value should be carefully preserved so that it can be of value for future use. Losing a field

book is a "cardinal sin" to a surveyor. It should not be used

for scratch computations or notes which have no permanent value

pertaining to engineering surveys. Less expensive notebooks

should be used for such purposes.

1.62 Types

There are two types of field books in general use: The looseleaf, and the leather or paper bound field book. Several kinds'

of line rulings are available. However, the kind in general use

is that shown in Figure 1.15^ page 1-28, Survey Notes for Gridding.

1.63 Identifying and Indexing

a. The outside cover of each field book should be niombered consecutively for each field office in which the book is kept

(Figure 1.20, page 1-39.) The same number may be placed on the

bound edge for ease in filing. The district, county, and state

should also be shown. This identification should be lettered in

India ink. Each field book should be further identified so that

it can be returned to the proper headquarters if lost (Figure

1.20). The wording should be lettered in India ink on the inside

of the front cover or the flyleaf of the field book.

b. The first four pages of the bound field book should be

reserved for the index (Figure 1.21, page 1-39). The following

pages should be numbered consecutively in the upper right-hand

corner of each page. Note that "page" in a field book means the

combination of the six ruled coliomns on the left and the cross

section paper on the right.

c. Loose-leaf field books have not been widely used in soil conservation work until recently. The use of this type of field

book permits the use of several different systems of indexing

and filing. It is recommended for use only on individual farm

Jobs. Bound field books should be used for all group enterprise

Jobs. All pages of a loose-leaf field book pertaining to a particular farm Job should be properly identified, indexed, stapled

together, and filed in the technician's folder for that farm.

The sheets should also be stapled in the folder for safe keeping.
1-39

GRAIN CO. S.C.D.

WISCONSIN

?\ÍÍD BOOK

W/S F/ELD BOOA: /S THE P/^OPERTY

OF r^E ¿//V/EED STATES DEPT OF

A^P/C¿/¿T¿/PE-SO/¿ CO/VSEP/AT/ON

SEPJ//Œ. F/A/DEP PLEASE PET¿/PA/

TO THE HEADQUARTERS OF THE

SO/l CONSERMT/ON

D/STR/CT CsT/e££r)

Cc/ry) . CSTATE).

OUTSIDE FRONT COVER FLY LEAF

FIGURE 1.20 FIELD BOOK IDENTIFICATION

INDEy.

Po^9

/ J.I-L0c7'ct'cr-'r(/eJ>rafn T^piS'àri^?'

i fjí' 5'57//^- (^0 9,"?¿2'íc6/'^ri?//A?

Oé^orr c é*¿v>¿v\'

7 A.i'1'. ¿é'ra ' T/7c ÍVc/r?- St*f {?ri7c<Ló

>/ /M ¿)iV7i7aZV^- é^/^eiZr7à . c év'<í-¿'ííe^

i6\ ¿\ '}brn7'i'E)s'yersyon- Cte7.k Qi'cc^eó

:t. Á-)?/ii//c¿' íV/^' ;¿/r/p/:,c^;,^^,)(.

J?r//7/7,rö'?7 ?ii')Oi'

IW. ¿Z/.¿ctÁ6 • ly/eûriiir -</î'/ S'î7îîJ

¿V Co.ilri7ér. yVb-^ ¿li'^éya'i.iei^f^C/rcùn

J/ Ce 0/':/,->/h. 4 ^Vo^ù? <t CiX'i/%7o

C'A ¿/nn ¿S^'varA ^¿3 ,>n7M sVo iProtA^

COQ X' SVTAOT

19, Íc\¿2-i7//^ /\^¿\ 4'^i/^6y )( ^?c^/coT

(i^ Oeep E^or/oqT

FIGURE 1.21 FIELD BOOK INDEX
l-ll-O

John Doe' ^arm- Terrace 3(/s/6 m General Plan

^^

AX<i3.:iâJ^iU:.^. Tk'inj\:s>^v. JUÍLí_¿ i^^.

Terrace Slope VerHcal Horiz. 6rades ¿enßth iUoidj^f ¿AMi^f/ni T'j .S'? ih)

No. Above lnien<al Jnterval in in i'J.3ro\rL

A va Avq. Avd. Vo Feet

\ - -'

-.

1 jro 1.7 170 azfûû.^ 300 }i ^¿ •''Jl !V

2 4% 3.6 90 V.'ZfoOA I030

3 é% 4. S 73 a?h0.3 I300 '^ .._,¿L J._

¿ Î J-' /_______.._^J¡L IIMMMMIiMMimMIMMim^^M

Soil 1 'upes ' Muscat ne. To 7)a- (pro JP'3 i .í: ^Cy<_

land

^r-

¿/se -i "^a/Hira ^ed 'C\Cr5.G,' H. 1

3/ope. 9 /-/:'o 1 ._^¿í'skí-_^^lL._

1

sJoitpes re iaHve/i / uniform -

1

li^{''}Ä'i:^,if<.-

ere s/on is noficei ible. be / nof 1 ericas - /

I.__X —1 ^aterracing needei i and yvorihv\éhile- \ .^^.é^ jiL

' ..

í^fi:

- -s-/k;5: W /^ii/K 'ùaL -'à' ~ ~ "

— T^'^^z—z 24.' a Je. one. ^'/<

_j'

J

r

John Doe ^arm - Terrac e Sus ^em Lauoui and check ^conid. from Faoe 2)

n rrace ^o. f

** u^' 9,1943

3fah'ng — Ciiec h'ncf

Channel Ridge 1

3fa. F5. í^A"^ T3 ¿ley. F3 £leK

Tï"^^^ 100.0 ,ï'ei/. XCO i'^-can^^ h\'&l iú chi?nr &U% cuhe¡-

O-tOO 3.7 73 loao 0.3 {01.0

O-f-50 3.0 1.3 1002 39 101.0 \

^v

l-f-OO 7.Ô 12 1003 3.9 lo/.e [

l-hóO 1.0 1.0 1003 \3.7 101.6 ^v s

2-^00 7.4 0.3 100.7 3.3 102.0 ^i ^

21-30 72 0.0 1009 3.3 ioe.2 \.JL.^

3WO 7.0 0.3 /O 1.0 3.2 1023 ÍH \

3^30 0.Ô3 0.5 1012 3.1 1024 5_i___3

4-hOO 0.1 ^í^^^ 0.3 100.7 3.7 1013 T,R '^\r y\

4-^30 0.35 3.0 m3 0.3 102.7 :^i;tbu e3-iOO ii 73 ¡02.0 0.0 102.9 '-:::^>;::ÍN\

3^30 3.33 72 1023 03 103.2 .__ oLÍ_V____L

e^oo 3.2 7.3 102.0 0.2 103.3 .__Í_yLj>-4

0^30

7^00 3.0

3.1

Ô.2

7.6 /0/.7

101.3

04

0.3

1031

1027

.^\M±-k-— K^ y^\

1430 7.9 7.2 1023 5.3 IO3.0 ' '^'' ^^-s^

a-ioo 7.6 7.0 IÛ2.^ 5.a I03.7 .c!ir,\ .cv.^A

- \- \

ô-f'30 7.7 l.O 102.3 50 I03.9 J____4Í____\-_

9-fOO 7.3 0.Ô 102.7 3.4 I04J

:::::::i:::i::::i____t__J__-I_

V

^ ^ "<:^

lyAir/o/vs

FIGURE 1.22 SAMPLE NOTES-TERRACE LAYOUT
2-1

PAET 2

PBEPABATION OF ENGINEERING DATA SHEETS

2.10 GENERAL

This part of the handbook is intended to:

(1) Show the purpose for data sheets and plans.

(2) Provide general information for preparation of data sheets.

(3) Give Service standards for data sheets and drawings.

2.20 PURPOSE

The purpose of data sheets and plans in soil and water conservation

work is to:

(1) Provide an orderly procedure and approach for analysis and solution of a problem.

(2) Provide details for construction of the planned measure or

works. A data sheet is defined as a drawing or set of drawings on

which is placed: First, all field survey and hydrologie data needed

for the purpose of analyzing a specific problem and planning a sound,

economical, and practical solution; second, outline or plan of contemplated works in true relation to other plotted data.

A set of drawings that include data sheets with necessary details and

specifications for construction is known as data sheets and plans.

Such data sheets and plans must meet the needs, be complete and

within an accuracy consistent with the type of works planned. It has

been demonstrated that time spent on preparation of data sheets and

careful analysis of problems will result in savings to coopérâtors

and a credit to the Soil Conservation Service.

2.30 INFORMATION AND MATERIALS NEEDED

2.31 Information Needed

a. Information required to meet data sheet needs varies with the

type and size of Job. Sample data sheets are included in various

other parts of the handbook such as Farm Ponds, Structures,

Drainage, etc. These will assist the planner in deciding on the

information needs. Generally an engineer will be responsible for

preparation of the data and detail plans for the more difficult

Jobs, while planners and aids will be mostly concerned with the

Class E Jobs.

The best test for detenaination of whether a set of data sheets

and plans contain all information required to meet the needs

intended is to assume that a qualified individual, who has never
2-2

seen the site and does not know local conditions, has the data

sheets and plans handed to him for use in staking the Job and

supervising construction. He may ask the following questions:

(1) Can the farm be located from the plans?

(2) Can the site on the farm be located from the plans?

(3) Can survey lines be relocated and the Job staked and

constructed at the exact location and elevation as intended?

(k) Are specifications for all the various parts of the

works included?

(5) Are quantities and bills of materials included?

When these questions can be answered in the affirmative the data

sheets and plans generally contain all needed information.

b. Data sheets and plans of completed works will be maintained

as records. All engineering works, regardless of size, type, or

kind of material used, will require maintenance. An "as built

plan" is invaluable for use in making sound maintenance recommendations. As built plans are also useful for study of structural design improvement, hydraulic performance and adaptation

of hydrologie data to local conditions. They may also be

invaluable in cases of legal disputes.

2.32 Material Needed

a. Many references will be made to the Eegional Cartographic

Handbook in the following discussion on materials. It is essential that such references be studied along with this handbook,

so as to gain a thorough \inderstanding of the subject.

Following is a list of materials needed in preparing engineering

data sheets and plans: (see Section 2, Part XI, Cartographic

Handbook for infomiation on use and care of drafting equipment)

(1) Profile tracing paper in which the sheet is ruled, as

illustrated in Figure 2.1, page 2-3.

(2) Plan-profile tracing paper in which the upper one-half

of the sheet is blank and the lower one-half is ruled, as

illustrated in Figure 2.1.

(3) Cross section tracing paper in which the sheet is ruled

as shown in Figure 2.1.

(i|-) Plain tracing paper, which is obtained in various sizes

(Figure 2.2, page 2-3).

(See Section 8, Part VIII, Cartographic Handbook on above.)
2-3

"^

Profile Plan- Profile Cross - Section

FIGURE 2.1 SAMPLE RULING OF PAPER

4=

"L"

SIZE

DRAWING

J:

pziiriiiiJ

"S"

"0"

SIZE

DRAWING

i

ïmz

All data and information token from other sources i.e. drowings

pre pored by other bureaus or by privóte componies should

be acknowledged on the drawing.

up..

SIZE

DRAWING

r-^-

3Q"

Title block dimensions ore suggested only. They may

bç increosed to occommodate additional information.

Revised 7-19-51

STANDARD CARTOGRAPHIC

DRAWING SIZES

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT. CHIEF

APHIC. APëROVAt.:

MA A2inger 3-L-2973

FIGURE 2.2 STANDARD DRAWING SIZES
2-i^

(5

(6

(7

(8

(9

(10

(11

(12

F, H, or HB pencils

30° - 60° and ¿4-5° triangles

T-square (optional)

Bow compass (optional)

Sandpaper pad

Engineer's scale, boxwood

Euby and art gum erasers

^ , With the possible exception of a ruling pen and a

planimeter, no other materials should be needed by a farm

planner or aid in the preparation of any data sheets which

either might be expected to prepare.

As the names imply, the plan-profile and cross section papers

are used in plotting profiles and cross sections. The plain

tracing paper is used for drawing of topographic sketches,

large scale plan views, and for layouts for which there is

not sufficient space on the plan portion of the plan-profile

sheets. All data sheets pertaining to one job should be on

the same size paper for appearance and filing convenience.

The smaller size "L," "N," and "O" plain sheets are used for

small tiling jobs or other small jobs where all the necessary

data can be placed on one of these small size sheets.

2.1|.0 DRAWING AM) DRAFTING STANDARDS

2.kl General

a. Engineering data sheets and other drawings prepared by field

personnel are not expected to be of a quality in drafting technique expected of a skilled draftsman. However, field personnel

whose duties require the preparation of engineering data sheets

or other drawings, are expected to perform such work in legible,

neat, orderly, and understandable manner. The appearance of the

drawings will affect the degree of confidence with which they

are received by persons outside the Service.

b. Lettering. Section k^ Part XI, Cartographic Handbook, gives

instructions on the style of lettering used on drawings in this

Region and information on how to improve your lettering. All

lettering and numbers within the body of engineering data sheets

should be 3/20" high for capitals and l/lO" high for lower case

letters. On the profile paper this is equivalent to three of

the finest lines high for capital letters and two lines high for

lower case letters. Titles used outside the title block should

be all capitals l/V' high (five of the finest lines on the profile paper) . Avoid the use of lettering any smaller than specified above; otherwise it will be difficult to read if the drawings are reduced in size by photostat reproduction.
2-5

c. Title Block. Every engineering data sheet or engineering

drawing of any nature must have a title block. The title block

is intended to present the following information in compact

form:

Subject of the drawing.

Plot of land to which it applies (when applicable).

The Department and Service responsible for preparing the

drawing.

The soil conservation district^ county, and state.

The names of the persons who surveyed, designed, drew, and

checked the drawing, together with the dates each performed.

Signature of the responsible person who approved the plan.

The regional drawing number is assigned by the Cartographic

Division for filing purposes.

The standard title block is shown in Figure 2.3, page 2-6. The

drawing paper referred to in Figures 2.1 and 2.2 may or may not

have the title block printed on the sheets. The title block can

be secured with gummed backs from the Cartographic Division by

ordering Drawing No. 3-L-l450i|-. These gimimed title blocks can

be glued on data sheets. They must always be placed in the

lower right-hand corner. Obviously, they cannot be used if the

drawing is to be blueline printed.

d. Use of Pencil. Nearly all field drawings will be done in

pencil. See Section 2, Part XI, Cartographic Handbook. With

reasonable care, a very creditable drawing can be turned out in

pencil. If the proper weight lines are used, good photostat

reproductions can be made. The exclusive use of pencil eliminates

a great deal of work involved in making ink tracings. In some

cases, however, it may be necessary to do considerable trial layout work in pencil on a contour sketch, as in an orchard contour

or terrace system. In such cases it will be desirable to'ink in

the contours before beginning the trial layout work to avoid

continual erasing of the contour lines.

e. Symbols. Map symbols are to be in conformance with symbols

shown in Figure 2.1+, page 2-7. Soil boring symbols are to be in

conformance with those shown in Figure 2.6. A legend explaining

the symbols used must be put on data sheets or engineering

drawings.

f. Scales. Bar scales should always be included for maps on

engineering data sheets. This is necessary because the original

scale of engineering data sheets and drawings is very often

reduced or enlarged when reproduced. A map scale given, for
2-6

COOPERATING miH,Jirand_^Rb/jr__,SJíA

COUNTY Jotnes ^^iMt^MiçbiâOd

SURVEYED-AVi-jSto^^ DATE^LZÙIZ^Â^

TILE DRAINAGE SYSTEM

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

UPPER MISSISSIPPI REGION

REFERENCE:

Field__Bgok_,NpJ2_.

CARTOGRAPHIC APPROVAL

7/.?/. TViTüt/

TECHNICAL APPROVAL

DESIGNED

John

Doe

DRAWN

John

¿mifh

CHECKED

John

Doe

DATE DRAWING NUMBER

Z-{Lea¡^e Bfank)

SHEET I OF 3

FIGURE 2.3 STANDARD TITLE BLOCK

instance, as one inch equals 100 feet, would have no meaning

after the drawing had been reduced to half size by photostat.

A bar scale, however, is reduced the same as the rest of the

drawing. Bar scales should be drawn similar to those shown as

"Duroseal Graphic Scales" on the last page of Section 12,

Part VIII, Cartographic Handbook. These scales can be used on

drawings to be photostated. It is unnecessary to include bar

scales on profiles, cross sections, and boring logs because

stationing and elevations are shown in each case.

g. North Arrows. North arrows should be shown near each

watershed map, location plan, and contour map. A standard

style north arrow is shown on the last page of Section 12,

Part VIII, Cartographic Handbook. It is general practice

among field engineers to use their own style north arrow, and

this is acceptable so long as it is not too elaborate.

h. Legal Descriptions. The legal description of the section

in which the main engineering works is located must be shown

in the space provided in the title block. In addition, each

watershed map, location plan, and contour map should be tied

into section or quarter section lines properly identified

(see Figure 2.5, page 2-8).

i. Bench Marks. Their location and identification must be

shown on all plans and maps.
2-7

SOIL CONSERVATION SERVICE

STANDARD MAPPING SYMBOLS FOR FARM CONSERVATION

PLANNING MAPS AND ENGINEERING DRAWINGS

BOUNDARY LINES

Watershed or Area.

DRAINAGE (Continued)

Levee -•»»,',';,',«111 n^iitffi »f »« Itwinn f

Section Line Spring ^.^--^^-^^D;::^

Form Boundary No Fence Lake or Pond -CXi-í^iítSsnr)

Permanent Fence x x x intermittent Lake or Pond.'^^

New Fence j j x Marsh

Crop Boundary No Fence Terrace

Field Boundary No Fence Diversion

HIGHWAYS a RAILROADS Grassed Watercourse

All Weather Road ^ Terrace Outlet

Dirt Road__ ===== Permanent Structure

Private or Field Road" __7_======:=: MISCELLANEOUS SYMBOLS

-V\S\VS\S\\SSSS\S\SSV

Bridge :

Single Track Railroad

Double Track Railroad

H=^ a

r

-H H

LAND USE SYMBOLS FOR SMALL

AREAS ONLY

Cultivated Land L

Woodland F

Permanent Pasture P

Idle Land X

Buildings and Lots H

Orchards 0

Permanent Hay (Grass and Legume) N

Wildlife -V

Unclassified _U

DRAINAGE

Continuous Stream, Large..

Continuous Stream, SmalL_

Intermittent Stream

Stream Disappears on Flat.

Stream Disappears in Sink__::r

Mine, Quarry,Gravel Pit /\

Cemetery I ' I

Ctiurch i

School House -1

Occupied Residence, Store _ "

ADDITIONAL SYMBOLS TO BE USED

TO SHOW ENGINEERING WORK ON

AGREEMENT MAPS OR ENGINEERING

DRAWINGS I-«

North Arrow

Section Center B

Section Corner ill. Tie

Existing Tile e eProposed Tile p «

Break in Tile Size ^^g'"^"

Break in Grade p,^ «

Relief Well ^'""^ '"''"

Breather

200'-4"

1%

Existing Open Ditchx

^ (HLess than 4'Deep)/

n r .. f^ c^ r^^ /Proposed Open Ditchv

Large Deep Gully ^ \/^\ ((Less than 4'Deep) )

/Gully, Cannot Cross with\ ^.^-

\Farm Implements I ^

/Gully, Can Cross with\

\Farm Implements ' -^

X. /Existing Open Ditchx

\(4'Deep or Over) /

/Proposed Open Ditch

\(4*Deep or Over) >-

S-L-ITlOe

FIGURE 2.4 STANDARD MAPPING AND DRAWING SYMBOLS

259293 O - 53
2-8

SCALE

O' 660" 1320'

330 990

MW.Cor

Sei

D.A:38Acre5

SCALE

660' 990' 1320'

FIGURE 2.5 PROPORTIONING METHOD OF SCALE ENLARGEMENT
2-9

2.k2 Profiles

a. Scales

All profiles should be drawn on profile paper or plan profile

paper. Horizontal scales should be 1 inch = 20^ ^0^ 80, 100,

200, or i^-OO feet, and the vertical scales should be 1 inch =

2, 4, or 8 feet. Only the heaviest lines (2-|-" squares) are

marked. Using the above horizontal scales, these heaviest

lines would be 50, 100, 200, 250, 500, or 1,000 feet apart.

These lines are marked in stations. Using the above vertical

scales, the heaviest lines (2f" squares) would be 5^ 10, or 20

feet apart, and elevations marked on these lines at full 5-^

10-, or 20-foot intervals.

b. Plotting

In selecting profile scales and starting points for plotting

profiles, first determine from the field notes the total lengtl

of profile to be plotted and the total difference in elevation,

Then select a horizontal scale and horizontal starting point

so that the entire profile will be well spaced on the profile

sheet, taking into account any other material planned tp be

drawn on the profile sheet. Then select a vertical scale and

a vertical starting point so that the entire profile will be

well spaced on the paper vertically, again considering any

other material contemplated to be drawn on the profile paper.

Briefly, this is a process of blocking out roughly the entire

profile so that it will all be on the sheet, well spaced, and

with sufficient room for other material to be drawn in later.

After selecting the starting point on the paper, the profile

points are plotted from the field survey notes. Adjacent

ground line points are connected with very light straight

lines, using a triangle as a straight edge, then traced over

free hand to make final lines.

Where approximately parallel profile lines are to be plotted

on the same profile as where a ditch bottom and banks are to

be shown, banks are named right and left, looking downstream.

Designed grade lines, such as proposed bottom of ditch or bottom grade of prepared tile line, are drawn in by using a

triangle as a straight edge and connecting computed plotted

points with a straight line.

2.-^3 Cross Sections

All cross sections should be plotted on cross section paper

(10 X 10 to the inch). They must be plotted as viewed looking

downstream. Where the top width of the cross section does not

exceed 280 feet, the cross section should be plotted to the

same horizontal and vertical scale, 1 inch = 5 feet, or 1 inch

r 10 feet, thereby giving an undistorted cross section. Where
2-10

the top width exceeds 280 feet, these scales should be altered

so that the full cross width can be drawn within the width of

the sheet. In such cases, the vertical scale should be 1 inch

= 5 or 10 feet, and the horizontal scale should be 1 inch =

20 jor 50 feet. The profile station at which each cross section

was taken should be indicated directly under each cross section.

At least two elevation markings should be shown for each cross

section drawn, so that the vertical scale will be clearly

indicated. Horizontal markings must also be shown for each

cross section. Bar scales are not used on cross sections.

2.kh Soil Boring Logs

a. Soil boring logs are used to:

(1) Analyze foundation conditions for contemplated structures and ponds.

(2) Analyze drainability of soils for contemplated open

ditch and tile drainage jobs.

(3) To detennine the presence of quicksand, rock, or

other undesirable sub-surface conditions in connection with

open ditch or tile drainage.

b. The boring logs should be plotted on the data sheet profiles or on the cross sections at the location where they were

taken whenever space is available. When space is not available, spot the location on the cross section or profile and

plot the boring logs, with proper identification, to one side.

In either case, the logs should be plotted on the same datum

used for the profiles or cross sections. Standard legend for

boring logs shown in Figure 2.6, page 2-11, will be used.

c. A further description of the various materials shown on

the standard is as follows:

Muck, Black or dark brown, well decomposed organic soil material accumulated under conditions of imperfect drainage. Light

and fluffy when dry. May contain some clay and sand.

Peat. Dark brown or brown, slightly decomposed organic soil

material accumulated \mder conditions of imperfect drainage.

Remnants or original vegetation may be distinguished, frequently fibrous and matted.

Silt Loam. A silt loam is a soil having a moderate amount of

fine grades of sand and only a small amount of clay, over half

of the particles being of the size called "silt." When dry it

may appear quite cloddy but the lumps can be readily broken,

and when pulverized it feels soft and floury. When wet the

soil readily runs together and puddles. Either dry or moist

it will form casts that can be freely handled without breaking.

If squeezed between thumb and finger it will not "ribbon" but

will give a broken appearance.
2-11

2

3

4

5

6

7

8

9

10

I I

12

13

14

15

16

17

Wiii

axm

ixm

^

n

%.

...1...../

SE

mrr

Muck

Peat

Silt loam

Silty clay loam

Sandy loam

Clay loam

Sandy clay

Clay

Sand

Fine gravel

Coarse gravel

Slate and shale

Coal seam

Sandstone

Limestone

Silty clay loam. A soil having a

moderate amount of clay and the fine

grades of sand with over half the

particles being silt. When dry it

appears cloddy and the lijmps break

with difficulty. When pulverized

it feels soft and floiiry and cannot be readily distinguished from

a silt loam. When wet the soil is

slightly plastic. It can be made

into casts which can be freely

handled without breaking. When

squeezed between the thumb and

finger it will form a thin "ribbon"

which will break readily. The surface of the "ribbon" will be flaky

rather than smooth as in the clay.

Sandy loam. A sandy loam is a soil

containing much sand but which has

enough silt and clay to make it somewhat coherent. The individual sand

grains can readily be seen and felt.

Squeezed when dry, it will form a

cast which will readily fall apart,

but if squeezed when moist a cast

can be formed that will bear careful handling without breaking.

Glacial drift (impervious)

Glacial drift (pervious)

FIGURE 2.6 LEGENDS FOR SOIL BORINGS

Clay loam. A clay loam is a finetextured soil which breaks into

clods or lumps that are hard when

dry. "When the moist soil is pinched

between the thumb and finger, it

will form a thin "ribbon" which will

break readily, barely sustaining its

own weight. The moist soil is plastic and will form a cast that

will bear much handling. When kneaded in the hand it does not

criimble readily but tends to work into a heavy compact mass.

Sandy clay. A soil containing a small amount of silt and a

moderate amount of sand, and at least half of the soil particles

of the size called clay. When dry the soil forms hard clods.

These will break into small granules under force. This texture

is best recognized in the moist condition. When pinched between

the thumb and finger, it will form a thin "ribbon" but the surface will be rough and gritty due to sand particles.

Clay. A clay is a fine-textured soil that forms very hard lumps

or clods when dry and is quite plastic and usually sticky when

wet. When the moist soil is pinched out between the thumb and

fingeis it will form a long, flexible "ribbon."
2-12

Sand. Sand is loose and single grained. The individual grains

can readily be seen or felt. Squeezed in the hand when dry, it

will fall apart when the pressure is released. Squeezed when

moist, it will fona a cast, but will crumble when touched.

Fine 'gravel. Resembles sand but the individual particles will

range in size up to that of the ordinary garden pea.

Coarse gravel. Resembles fine gravel but the particles are

larger. The size is usually an inch or less but may range up to

the size of a hen's egg. Material larger than this would interfere with the operation of a trenching machine in drainage work.

Slate and shale. Finely stratified or laminated beds of finetextured material as silt or clay. Slate is much more dense and

compact than shale.

Coal seam. Includes layers of variable thickness of coal.

Sandstone. Rocks of variable thickness. The sand particles can

usually be distinguished. This rock may be dense and hard and

resistant to crushing, or it may be readily broken down by a

small amoimt of force.

Limestone. A dense compact rock usually white, gray, or bluegray in color. In some cases, individual crystal structure may

be identified. Can be distinguished from sandstone by use of

diluted hydrochloric acid (l/lO normal solution) which produces

an effervescence in the limestone.

Glacial drift (impervious). Includes glacial deposits, both

stratified and unstratified; composed largely of clay, gravel

and boulders, and may include some silt and sand.

Glacial drift (pervious). Includes glacial deposits, both

stratified and unstratified; composed largely of sand and silt,

gravel and boulders; contains small amounts of clay material.

2.50 WATERSHED LOCATION MAP

2.51 A watershed location map may be defined as a map that shows

contributing watershed boundary and the location, by symbol, of

the proposed works. It must also show all other information

that is pertinent to analysis and design of the proposed works.

Such information may include some or all of the following:

a. Average slopes of various reaches of the principal watercourses .

b. Average slope of the land in various parts of the watershed.

(Generally this can be gotten from the conservation survey map.)

c. Land-use plan broken down into cultivated timber and pasture

areas. (This may be in tabulated form.)
2-13

d. Area of each of the predominant soil types or groups within

the watershed. (This may be in tabulated fonn.)

e. Location of proposed work by symbol.

f. Location and size of bridges^ culverts^ and other structures

that affect or are affected by the proposed works.

g. Names and extent of property ownership within the watershed.

h. Location of roads and buildings; also railroad drainage

ditches^ telephone and pipe lines when any of these affect or

are affected by the proposed works.

i. Stationing along the route the profile was taken at points

such as road crossings^ property lines, junction with watercourses, and at any other points which will help in identification of points on the map with points on the plotted profiles.

j. Section corner or section center and legal description.

2.52 Watershed location maps in some form are required for all

proposed works. The size and scale should vary with the size of

the watershed and information needed. Generally the map should

be not less than four inches square on the data sheet. It

should be prepared to one of the following scales:

1 inch = 165 feet or 32 inches = 1 mile

1 inch = 330 feet or I6 inches = 1 mile

1 inch = 660 feet or 8 inches = 1 mile

1 inch = 1320 feet or k inches = 1 mile

2.53 A watershed location map is generally prepared by one or a

combination of the following methods:

a. Inking information on aerial photo and cementing photo on

data sheet.

b. Tracing direct from aerial photo on data sheet.

c. Enlarging aerial photo data by proportioning on cross section paper or enlarging direct with panograph. In either case

the watershed and location map is traced on the data sheet from

the enlargement. Figure 2.5, page 2-8, shows enlargement method

by proportioning on cross section paper.

The following may be used as a guide for determination of a

suitable scale:
Up to 10 acres - 1 inch = I65 feet

10 to i^-O acres - 1 inch = 330 feet

ko to 160 acres - 1 inch = 66O feet

160 to 640 acres - 1 inch = 1320 feet

2.60 LOCATION PLM

2.61 A location plan is a drawing used for detail planning and

staking out the Job. Generally it is drawn to a scale larger

than the watershed and location map. A location plan should

generally show the following:

a. Location of survey centerline or other survey lines with

ties to permanent objects.

b. Location of proposed works with reference to survey lines.

c. Location and elevation of BMs.

d. Outline of existing watercourses, ditches, or tile lines

when these affect designs.

e. Location of soil borings.

f. Location of existing fences, property lines, buildings,

roads, culverts, bridges, springs, wells, borrow pits, etc.

g. Contour lines.

2.62 The difference between a watershed location map and a location

plan is that a watershed and location map shows information

needed for analysis and solution of a problem, along with the

general location of the proposed works, while the location plan

shows information needed for detail planning and details for

staking out the proposed work.

2.63 The scale for a location plan drawing will vary with the kind

and size of Job. The following may be used as a guide:

a. For structure - 1 inch = 10, 20, 30, or kO feet, with contour

lines shown at 1 to 5 feet vertical intervals.

b. For drainage (open ditch, surface ditch and tile) Class E

Jobs - 1 inch = 100, 200, 330, or 66O feet.

c. For drainage (open ditch, surface ditch) Class D and larger

Jobs - 1 inch = 100, 200, and up to 1,000 feet.

d. For drainage (tile) Class D and larger - 1 inch = 100 or 200

feet.
2-15

,6k A location plan may be combined with a watershed location map

on some of the smaller Jobs, especially on small drainage work.

Discretion should be exercised in making such a combination,

inasmuch as all information needed must be on such a map. It

must be clear, understandable, and so placed without undue

•cluttering on the drawing.

.65 Drawings in outline form with space provided for recording

planning, layout, and construction details are available. These

should be used where applicable as data sheets and plans. Their

use will be confined to the less complex jobs that require only

the data suggested in order to do a sound job of planning and

construction. For examples of this type data sheet see Figure

U.I3, page ^-20, and Figure 7.7, page 7-11. These are called

"Fill in Data Sheets."
3-1

PAET 3

RAIKFALL-RUNOFF-SPRING AKD

STREAM FLOW MEASUBIMENTS

3.10 EROSION CONTROL

3.11 Relationship of Rainfall to Runoff

a. Runoff is that portion of the rainfall which leaves a field

either by surface flow or by sub-surface such as through tile or

springs.

3.12 Factors Affecting Runoff

a. The rate and intensity of rainfall varies over the region.

It is usually expressed in inches per hour. The variation of

rainfall in the region is expressed as a factor. (Figures 3.1

and 3.2.) See rainfall factor "R" in small map. This factor

multiplied by figure selected from charts based on SW and

watershed area will give you total runoff "Q" for the area which

is the rate of runoff in cubic feet per second.

b. Other factors affecting runoff are:

Relief (slope of the land)

Soil infiltration

Vegetal cover

Surface storage

These are adequately defined in Figures 3.1 and 3.2. Proper

values are selected, based on watershed characteristics, and

these are added together to get SW which is shown in example,

Paragraph 3.1^. 5W is called the summation of watershed

characteristics.

3.13 Rainfall Frequency

a. Rainfall frequency can be defined as a relative figure based

on probability. In other words, the probability of a big rain

conducive to high runoff falling on a watershed is much greater

in a 50-year period than it is in a 25- or 10-year period.

Therefore, runoff for 50-year design is greater than for 25-year,

and 25-year in turn is greater than for 10-year. Runoff for 10-

and 50-year frequencies can be obtained from Figures 3.1 and 3.2.

b. 10-year frequency should be used:

In figuring the size of grassed waterways.
3-2

RUN-OFF CHART FOR DESIGN OF GRASS WATERWAYS

BASED ON 10 YEARS FREQUENCY AND RAINFALL FACTOR OF 1.0

DRAINAGE

AREA

IN ACRES

30 35 40

WA

45 J

FERSHED

50 J

CHARAC

55

TERISTIC

60

S

65 70 75 85

PiO = CUBIC FEET PER SECOND

4 5 7 8 9 10 11 13 15 17 20 24

6 6 8 10 II 13 16 18 21 24 28 34

8 7 9 12 13 17 20 24 28 32 37 44

10 8 10 14 16 21 25 30 35 40 46 53

12 9 11 16 19 24 29 35 41 48 54 62

14 10 13 18 22 28 33 40 47 55 62 71

16 1 1 15 20 25 31 36. 45 53 62 1 70 80

18 12 17 22 28 34 42 50 5S 7S 78 89

20 14 19 24 31 38 46 55 65 76 86 98

25 16 22 28 36 46 55 66 78 «?0 103 118

30 18 25 32 42 53 64 77 91 105 120 139

35 20 28 36 47 60 73 87 104 120 137 159

40 22 32 41 53 68 82 98 117 135 154 179

45 24 36 46 59 76 91 109 130 150 171 200

50 26 40 51 65 83 100 1 19 142 165 tbo 220

60 30 45 59 76 97 117 139 165 193 221 259

70 34 50 66 87 110 133 159 188 221 253 298

80 38 55 74 97 123 149 179 2il .. *8 285 338

90 42 60 81 107 136 166 199 234 274 317 378

too 46 65 88 1 17 150 182 218 256 300 348 418

120 53 75 102 135 175 213 256 300 30' 410 487

140 60 85 116 154 200 244 293 344 401 471 556

160 67 95 129 172 224 275 529 388 45. 5ií3 625

180 73 105 142 190 248 305 364 432 500 585 694

200 79 115 155 2 07 271 334 398 476 550 640 764

220 85 124 168 224 294 363 432 516 598 693 832

240 91 132 180 241 317 392 464 556 645 746 899

260 97 141 192 257 340 421 496 595 691 799 964

280 102 149 204 273 362 450 528 634 736 852 1028

300 108 158 216 289 384 480 560 672 781 905 1090

320 1 14 167 228 305 407 505 591 709 824 956 1150

340 119 175 240 321 4 29 530 623 746 867 1007 1210

360 124 184 253 337 451 555 654 7C3 909 1058 1270

380 129 192 265 355 473 580 684 820 952 1109 1330

400 135 200 277 371 494 605 713 856 994 1160 1390

420 141 208 288 386 515 629 741 891 1035 1209

440 146 216 299 401 535 653 769 926 1076 1257

460 151 224 310 416 554 677 797 961 1117 1303

480 156 232 321 432 572 700 825 996 1158 1348

500 161 239 332 447 590 723 853 lOiu 1199 1392

520 166 246 342 462 607 746 881

1098

1238 1435

540 171 253 352 476 624 769 909 1277 1478

560 176 260 362 490 641 791 937 1131 13;:) 1521

580 181 267 372 504 658 813 965 1164 1350 1563

600 185 274 382 518 675 835 993 1197 IZCL .605 .

HOW TO USE CHART

Determine numerical characteristic of watershed. From the

chart under this numerical characteristic and opposite the

drainage oreo read the probable run-off for o Roinfoll

Factor of 1.0. Multiply this number by rainfall foctor of your

work unit. This will give the required cf.s. for waterway

design.

DESIGNATION

OF WATERSHED

CHARACTERISTICS

RUN-OFF-PRODUCING CHARACTERISTICS |

too

EXTREME

75

HIGH

50

NORMAL

25

LOW

RELIEF

(40)

Steep,rugged terrain,with

overoge slopes generally

obove 30 7.

(30)

Hilly.with overage slopes

of 10 to 30 %

(20)

Rolling,with overage slopes

of 5 to 10%

(10)

Relotively fiot land,with

averoge slopes of Oto 5 7.

SOIL INFILTRATION

(20)

No effective soil cover,

either rock or thin soil mantle

of negligible infiltration

capacity.

(15)

Slow to toke up woter: cloy

or other soil of low infiltration capacity, such OS heavy

gumbo.

(10)

Normal; deep loom with

infiltration about equal to

that of typical prairie soil.

(5)

High; deep sond or other

soil that tokes up woter

readily and rapidly.

VEGETAL COVER

(20)

No effective plant cover,

bore or very sparse cover.

(15)

Poor to foir; cleon-cultivoted

crops or poor natural cover;

less thon 10% of drainage

oreo under good cover.

(10)

Foir to good; about 50% of

drainage orea in good grosslond,woodland, or equivalent

cover; not more than 507« of

area in clean-cultivated crops.

(5)

Good to excellent; about 907.

of droinoge area In good

grassland, woodland, or

equivalent cover.

SURFACE STORAGE

(20)

Negligible: surface depressions

few and sholtow; droinogeways steep and small; no

ponds or marshes.

(15)

Low; well-defined system of

smoll drainage-ways; no

ponds or morshes.

(10)

depression storage; drainage

system similar tothotof

typical proirie londs; lakes,

ponds and morshes less

thon 27e of drainage oreo.

(5)

High; surface-depression

storoge high; droinoge system

not sharply defined; large

flood-ploin storage or o

large number of lakes,

ponds or marshes.

RAINFALL FACTORS R

LOCATE YOUR WORK UNIT ON

ABOVE RAINFALL MAP AND

DETERMINE RAINFALL FACTOR.

WORK UNIT

RAINFALL FACTOR

RUN-OFF CHART FOR DESIGN

OF GRASS WATERWAYS

REGIONAL OFFICE

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H, H. BENNETT, CHIEF

TECHNICAL APfROVALi

¡OMPILED: DRAWN: CHECKED- DATE'.

PJ. OlewofH/owslu O.D.R e-r-46

¿^^«^«^•'••^^^[¿.^.^c^^^ty^^'t^

DRW6. NO.

J-L-J4034

FIGURE 3.1 RUNOFF CHART FOR DESIGN OF GRASSED WATERWAYS
3-3

RUN-OFF CHART FOR DESIGN OF PERMANENT STRUCTURES

BASED ON 50 YEARS FREQUENCY AND RAINFALL FACTOR OF 1.0

DRAINAGE

AREA

IN ACRES

25 30 35 40 45

WATÍ

50

:RSHED

55

CHAR/

60 1

kCTERlS

65 1

rics

75 85 too

HOW TO USE CHART

Determine numerical characteristic of watershed. From the chart

under this numerical characteristic and opposite the drainage

area read the probable run-off

for a Rainfall Factor of 1.0. ty^ultiply this number by rainfall factor of your work unit. This will

give the required c.f.s. for permanent structure design.

Pf)0 = CUBIC FEET PER SECOND

4 5 7 10 1 1 13 14 15 18 21 24 28 34 36

6 6 8 1 1 14 15 18 23 25 30 34 40 48 51

8 7 10 13 17 18 24 28 34 40 45 52 62 66

10 8 1 1 15 19 24 29 35 43 50 58 66 75 81

12 9 12 17 22 28 34 41 50 59 68 78 88 97

14 10 14 19 25 32 39 47 57 68 78 90 101 1 12

16 1 1 15 21 28 36 44 53 64 76 87 too 1 14 127

18 12 17 24 31 40 49 59 71 84 96 1 10 126 142

20 13 19 26 33 43 53 64 77 92 105 120 138 155

25 16 22 31 40 52 64 78 93 1 10 128 146 168 190

30 18 25 36 47 60 75 91 109 128 149 172 198 225

35 20 28 41 53 68 86 104 124 146 170 196 228 260

40 22 31 45 59 76 97 1 17 139 164 190 221 257 295

45 24 34 49 65 84 107 130 154 182 210 245 286 330

50 26 37 53 71 92 117 142 168 200 230 267 315 365

60 29 43 62 82 108 136 165 197 234 270 314 366 435

70 32 49 70 93 123 155 188 226 268 310 360 425 505

80 36 54 78 104 137 173 21 I 255 301 350 406 478 570

90 40 59 85 114 151 193 233 28, 334 389 448 530 635

100 43 64 92 124 165 210 255 307 365 426 490 590 700

120 49 74 107 144 192 246 300 359 427 500 574 690 825

140 55 84 121 164 218 281 345 410 487 570 658 790 950

160 61 94 134 183 243 315 390 460 547 640 740 890 1070

ISO 67 103 147 202 268 349 430 510 607 710 820 990 1 190

200 73 1 1 1 160 220 292 383 470 560 667 780 900 1080 1310

220 78 119 173 237 316 416 510 610 724 845 980 1170 1420

240 83 127 186 254 340 449 550 660 781 910 1060 1260 1530

260 88 135 199 271 363 481 590 704 838 970 1134 1350 1640

280 93 143 211 288 386 513 630 748 894 1030 1207 1440 1750

300 98 151 223 305 409 545 670 792 950 1090 1280 1530 I860

320 103 159 235 322 432 576 705 836 1000 1150 1350 1620 1970

340 108 167 247 339 455 604 740 880 1050 1210 1420 1710 2080

360 1 13 174 259 356 478 633 775 924 1100 1270 1490 1800 2190

380 118 182 270 373 501 662 810 967 1150 1330 1560 1890 2290

400 123 190 281 390 523 691 845 1010 1200 1390 1630 1980 2390

420 128 197 292 405 544 720 880 1048 1248 1448 1694 2064 2490

440 133 204 303 420 565 748 915 1086 1296 1506 1758 2148 2590

msk

460 137 21 1 314 435 586 776 950 1124 1344 1564 1822 2232 2690

480 141 218 325 450 607 803 985 1162 1392 1622 1886 2316 2790

500 145 225 335 465 628 830 1020 1200 1440 1680 1950 2400 2885

520 149 232 345 480 648 856 1050 1238 I486 1734 2010 2476 2980

540 153 239 355 495 668 882 1080 1276 1532 1788 2070 2552 3075

560 157 245 365 510 688 908 1120 1314 1578 1842 2130 2628 3170

580 161 250 375 525 708 934 1 140 1352 1624 1896 2190 2704 3265

600 165 255 385 540 728 960 1170 1390 1670 1950 2250 2780 3360 RAINFALL FACTORS"R"

DESIGN

OF WATE

GHARACTE

i\TION

RSHED

:RISTICS

i RUN-OFF-PRODUCING CHARACTERISTICS LOCATE YOUR WORK UNIT ON

ABOVE RAINFALL MAP AND DETERMINE RAINFALL FACTOR

100

EXTREME

75

HIGH

50

NORMAL

25

LOW

RELIEF

(40)

Steep,rugged terrain, with

overage slopes generally

above 30%

(30)

Hilly, with average slopes

of 10 to 30%

(20)

Rolling, with average slopes

of 5 to 10%

(10)

Relatively flat Ian

average slopes of

1, with

0 to 5%

WORK UN

RAINFALL

T __ __ __

FACTOR

SOIL INFILTRATION

(20)

No effective soil cover,

either rocK or thin soil montle

of negligible infiltration capacity

(15)

Slow to take up water; clay

or other soil of low infiltration capacity, such as heavy

gumbo

(10)

Normal; deep loam with infiltration about equal to that

of typical prairie soil

(5)

High; deep sand or

that tal<es up wate

and rapidly

other soil

r readily

RUN-OFF CHART FOR DESIGN

OF PERMANENT STRUCTURES

VEGETAL COVER

(20)

No effective plant cover;

bore or very sparce cover.

(15)

Poor to fair; clean-cultivated

crops or poor natural cover;

less than 10% of drainage

area under good cover

(10)

Fair to good;about 50% of

drainage area in good grassland, woodland,or equivalent

cover',not more tt^an 50% of

(5)

Good to excellent; 0

of drainage area in

equivalent cover

bout 907o

good

J,or

REGION 3 REGIONAL OFFICE

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H.H.BENNETT, CHIEF

SURFACE STORAGE

(20)

Negligible; surfoce depressions few and shallow; droinage-wdys steep and small;

no ponds or marshes

(15)

Low; well-defined system of

small droinage-woys; no

ponds or marshes

(10)

Normal;considerable surface-depression storage;

drainage system similar to

that of typical prairie

lands; lakes,ponds ond

(5)

High; surfoce-depr

storage high;droir

tem not sharply d

lorge flood-plain

or a large number

ession

age sysefined;

storage

of lakes,

REFERENCE

CARTOGRAPHIC APPROVAL:

/

TECHNICAL APPROVAL: 1

droinog

less rna 1 ¿."lo OT ponas 0 ICOMlPILED-- DRAWN:

R.B.BH.R.

CHECKED:

J.D.P.

DATE:

6-4-47

DRWG. NO. 1

3-L-15084 1

FIGURE 3.2 RUNOFF CHART FOR DESIGN OF PERMANENT STRUCTURES
3-^

In figuring diversions vhere vegetated outlets are provided.

c, 50-year frequency should be used on all structures impounding water or involving spillways constructed of permanent

materials.

3.1k Example for figuring runoff for a structure of permanent

materials. Use 50-year frequency.

Watershed

93 acres drainage area

60 acres cropland (strip cropped)

33 acres pasture

6^ average slope

Soil - average loam

Waterways - well defined

Then from Figure 3-2, SW equals:

Relief for average slope 6^ 12

Soil infiltration for average loam 10

Vegetal cover - 10 for strip cropped area and

5 for pasture area

Interpolating (10 x 60) -f (5 x 33) 8

93

Surface storage well defined drainage system 1^

SW ^5

Then from Figure 3.2 for 50-year frequency^ runoff from chart

with a SW of ^5 and 90 acres = 151.

Then if structure were to be constructed in Ashland County,

Wisconsin,

R = 0.7

Q = (151) (0.7)

= 106 cu. ft. per sec.

The design of waterways follows the same procedure using Figure

3.1.
3-5

3.20 DRAINAGE RUNOFF

3.21 General

The basic difference between runoff for erosion control and for

drainage is in degree of protection provided• In erosion control work, such as in the design and construction of earth dams,

momentary peak flows must be provided for so as to prevent

damage from overtopping. In drainage runoff, on the other hand,

these momentary peaks are allowed to flood out over the land.

Usually slopes are not great enough for serious erosion to

result, and the water is removed at a rate great enough to permit its removal before crop damage results.

3.22 For quantities of runoff for open ditch or tile, see Part 11.

3,30 MEASURING STREAM AND SPRING FLOWS

3.31 General

A ready way to measure stream flow is needed in preliminary

planning when a stream is to be used for irrigation or a spring

is to be used for a water supply.

Two types of weirs are adapted to measuring the flow of small

streams. They are:

a. Rectangular weir

b. 900 V notch

3.32 The rectangular weir is adapted to measuring fairly large

stream flows. The discharge is dependent upon both width

and depth of the weir. Therefore, no attempt will be made to

set up tables for this type of weir. If the flow of the stream

is such that it is necessary to use this type of measuring

equipment an engineer should be consulted.

The 90^ V notch weir is probably best for measuring small flows

common on low stream or small spring flows. It can be made by

cutting a triangular 90^ notch in a wooden bulkhead, as illustrated in Figure 3.3.
3-6

1 X 4 - Floorin

/

g Notch Depth 8 to 12

/

V^^

\ /

\/^

ELEVATION

{Jjr- 2x4-Studs zJJ

PLAN

Ï 1

DETAIL OF SO"" WEIR

FIGURE 3.3 CONSTRUCTION DETAILS FOR 90-DEGREE TRIANGULAR NOTCH

The depth of the notch may be from 8" to 12" deep. The material should he one-inch flooring or other tongue and groved

material. Posts (2x4) should be placed at the end and on each

side of the notch. It must be made deep enough to go into the

ditch bottom a sufficient distance to prevent undercutting and

wide enough to tie into the banks. The amoimt of water flowing

can be obtained from the table on the next page by merely

observing the depth of flow. If foot gauges are placed on each

side of the weir a convenient method for leveling weir and reading water stages will be provided.

The best method to prevent seepage under the weir is to tack a

piece of canvas below the weir on upstream side.

One precaution, if discharge figures are to be accurate, is to

provide enough distance below the weir so that it will flow

without submergence of the downstream side. The bottom of the

V must be above the water on the downstream side.
3-7

DISCHARGE TABLE FOR 90-OE6REE TRIANGULAR NOTCH

Head

in

Head

in

Discliarge Head

in

Head

in

Discharge

gal. second- gal. secondfeet inches min. feet feet inclies min. feet

0.20 2-3/8 21 0.046 .61 7-5/16 327 .730

.21 2-1/2 23 .052 .62 7-7/16 341 .760

.22 2-5/8 26 .058 .63 7-9/16 354 .790

.23 2-3/i^ 29 .065 .64 7-11/16 369 .822

.2k 2-7/8 32 .072 .65 7-13/16 383 .854

.25 3 36 .080 .66 7-15/16 398 .887

.26 3-1/8 39 .088 .61 8-1/16 413 .921

.27 3-1/4 43 .096 .68 8-3/16 428 .955

.28 3-3/8 47 .106 .69 8-1/4 444 .991

.29 3-1/2 52 .115 .70 8-3/8 462 1.03

.30 3-5/8 56 .125 .71 8-1/2 475 1.06

.31 3-3/4 61 .136 .72 8-5/8 493 1.10

.32 3-13/16 GG .147 .73 8-3/4 511 1.14

.33 3-15/16 71 .159 .74 8-7/8 529 1.18

.Zk 4-1/16 77 .171 .75 9 547 1.22

.35 4-3/16 83 .184 .76 9-1/8 565 1.26

.36 4-5/16 88 .197 .77 9-1/4 583 1.30

.37 4-7/16 94 .211 .78 9-3/8 601 1.34

.38 4-9/16 101 .226 .79 9-1/2 623 1.39

.39 4-11/16 108 .241 .80 9-5/8 641 1.43

M 4-13/16 115 .256 .81 9-3/4 663 1.48

M 4-15/16 122 .272 .82 9-13/16 681 1.52

.42 5-1/16 130 .289 .83 9-15/16 705 1.57

M 5-3/16 137 .306 .84 10-1/16 722 1.61

M 5-1/4 145 .324 .85 10-3/16 744 1.66

M 5-3/8 154 .343 .86 10-5/16 767 1.71

.il 6 5-1/2 162 .362 .87 10-7/16 790 1.76

M 5-5/8 171 .382 .88 10-9/16 812 1.81

M 5-3/4 181 .403 .89 10-11/16 834 1.86

M 5-7/8 190 .424 .90 10-13/16 861 1.92

.50 6 200 .445 .91 10-15/16 883 1.97

.51 6-1/8 210 .468 .92 11-1/16 907 2.02

.52 6-1/4 220 .491 .93 11-3/16 934 2.08

.53 6-3/8 231 .515 .94 11-1/4 956 2.13

.5i^ 6-1/2 242 .539 .95 11-3/8 982 2.19

.55 6-5/8 253 .564 .96 11-1/2 1010 2.25

.56 6-3/4 265 .590 .97 11-5/8 1037 2.31

.57 6-13/16 277 .617 .9Q 11-3/4 1064 2.37

.58 6-15/16 289 .644 .99 11-7/8 1090 2.43

.59 7-1/16 301 .672 1.00 12 1118 2.49

.60 7-3/16 314 .700

FIGURE 3.4 DISCHARGE TABLE FO R 90-OEGREE TRIANGUU^R NOTCH1

259293 O - 53 - 5
4-1

PABT k

FAIM POHDS

4.10 GENERAL

4.11 Scope and Limitations

a. Farm ponds or reservoirs are:

Retention reservoirs in \^ich the primary purpose is the

storage of water for fut\ire use.

Detention reservoirs in which tCTçorary flood-storage

reduces the peak flow immediately below the pond.

b. The farm planner is limited in designing ponds as outlined

in Regional Memorandum No. 60 (Bevised).

4.12 Uses

a. Farm ponds are constructed most frequently for storage of

stock water. The amoxmt of storage should be sufficient to allow

for seepage and evaporation losses and also to satisfy the

requirements for stock water for an extended drouth period.

Seepage and evaporation amount to approximately three feet or

more annually, iinless unusual soil and climatic conditions prevail at the pond site. Stock water requirements may be estimated by using a value of 15 gallons of water per day per

animal unit for a drouth period of approximately six months. In

figuring animal units, cattle and horses are estimated at one

animal unit per head, while sheep and hogs are calculated at onetenth animal unit each.

b. Where storage is to be used for irrigation, great care should

be taken to insure that sufficient water is available to provide

an adequate amo\mt for each acre to be irrigated. See Part 12,

"Irrigation," for details.

c. Water storage may be invaluable for protection in case of

fire. In order to be effective, water must be applied at a rate

of approximately 500 gallons per minute. This would mean a

supply of over .092 acre-foot for an hour. Minimum for fire,

50,000 gallons (after losses).

d. Where pond storage is to be used for spray water in addition

to stock water, very little, if any, additional capacity needs

to be considered. The amount required for spray water (.02 acrefoot per acre of orchard) is relatively small, and the dmand

usually comes at a time of year when frequent rains will replace

this withdrawal.
k-2

e. One of the uses of the farm pond, rating high in farmer

interest, is recreation and production of fish for food. For

this purpose the farm pond should have a surface area of not

less than one-quarter of an acre and an average depth of 6 feet

with 8 to 10 feet of depth in 25 percent of the area.

f. Where local conditions permit, ponds may he designed as

detention reservoirs by providing more than the usual amount of

temporary storage above the crest of the mechanical spillway.

They should be designed in accordance with procediires outlined

in paragraph k.k2 for watersheds under 30 acres. For larger

watersheds, flood routing curves should be prepared by an engineer .

g. There is a growing demand for farm ponds to be \ised as a

home water supply. The dangers of pollution and the difficulty

of proper chlorination and filtration make this use doubtful.

Most State boards of health strongly oppose the use of open

surface storage as a source for a household water supply.

1|..20 SELECTING THE POND SITE

i|..21 Watershed

a. There are many advantages to a site near the farm buildings.

Such a location makes fire protection more effective and provides a supply of water at the farmstead for livestock and for

other uses at a minimum of expense and difficulty. A location

near the buildings also is more readily available for recreational purposes and the pond is more likely to be inspected and

properly maintained. There are instances, of course, where it

is desirable to locate the pond in a remote part of the farm in

order to provide stock water for an isolated pasture area.

b. In selecting a pond site, the possibilities of pollution of

the water sijpply should be considered. Not only should drainage

from a barnyard be avoided, but drainage from land not under the

farmer*s control is frequently questionable, because it may be a

source of contagion (Bang's disease, cholera, etc.) to livestock.

A watershed wholly within the farm is to be desired.

c. The pond watershed preferably should have a high percent of

vegetative cover, so that siltation of the impounded area will

be kept to a minimum. The watershed should have 50 percent or

more in grass cover, if possible, and any rolling areas not in

vegetation should be under conservation treatment that will give

effective control.

d. The watershed should be large enough to provide the required

amount of water but it should not be disproportionately large in

comparison to the impounded area. A proper relationship between

pondage area and watershed area, therefore, is desirable. If a

ratio of one acre of pond siirface to less than six acres of

watershed exists, there may be difficulty in keeping the pond
^-3

filled diiring extended periods of dry weather, or in case of

abnormal use. Where a ratio of one acre of pond surface to more

than 20 acres of watershed exists, the water disposal problem

will be complicated and expensive because of excessive spillwaycosts, and excessive siltation of the impounded area is likely

to occur. These latter sites should be investigated and designed

by an engineer.

e. Exposure of the impounded area with reference to the prevailing winds should also be considered. Every effort should be made

to locate the pond so that the prevailing wave action is away

from the fill.

4.22 Fill Site

a. A location should be selected where the effective depth

would be eight to ten feet over at least twenty-five percent of

the pond at normal water level. A pond with less depth will not

provide cool enough temperatiire for fish and would frequently

not provide enough capacity after seepage and evaporation losses

had been met.

b. Select sites that will provide a maximum amount of storage

with the least amount of fill.

c. An earth fill is no better than its foundation. A good

foundation would be a slowly pervious material not only under

the fill but under the pond water area as well. Fill foundations

should be avoided where there is shallow cover to rock, sand, or

gravel. If a fill is to be built under these conditions, special

precautions will be necessary. Peat and marl areas should be

avoided as fill foundations.

d. "Wherever possible, select a site that will provide a nattiral

vegetative spillway.

e. Good fill material is important in constructing farm ponds.

A supply should be readily available to the fill site. Any conbination of a rather wide range of mixtures of fine gravel, sand,

silt, and clay in such proportions that a minimum of voids exist,

will be excellent fill material for dams within the scope of the

farm planner*s authority to approve. The following or similar

soils will be suitable for fill material:

Shelby silt loam

Carrington silt loam

Miami silt loam

Milaca silt loam

Wellston silt loam
k-k

The following or similar soils are poor fill material:

Any sandy loam

Boxton gravelly silt loam

Ida silt loam

Cincinnati silt loam

Any soil containing alkali

1^.30 SURVEYS

If. 31 Watershed

a. The procedure for the watershed survey is given in Part 1.

The acreage of the watershed, average percent slope, cover, and

soil type should be obtained and recorded.

If.32 Fill Site

a. The soirvey should include a profile, cross section, and soil

borings on centerline of fill and at intervals in the pond area.

Conto\ir lines should be used where an accurate figure for flood

storage capacity is required. See Part 1 for the procedure to

be followed for making a survey of the fill and pond site.

k.kO DESIGN

k.kl Choice of Spillways

a. The kind of spillway to be used will depend on the size of

watershed and site conditions. Generally watersheds from 10 to

30 acres will require a combination of mechanical and vegetative

spillways. This is desirable because it eliminates a prolonged

trickle flow which might damage the sod. Watersheds under 10

acres often require only a good vegetative spillway. Watersheds

over 30 acres will require the services of an engineer for

spillway design.

k.k2 Mechanical Spillway

a. In using stage design table. Figure k.l, the size of the

spillway tube and its capacity to carry runoff is fixed (either

8- or 10-inch pipe). Therefore, design enough flood storage to

take care of the rest of the normal runoff. The table shows the

relationship between the pond area (soirface area of the pond at

the elevation of the crest of the mechanical spillway), the

acres of drainage area, and the stage (depth of water above the

mechanical spillway necessary to provide the required storage).

b. To solve a particular problem determine the flood characteristics ( S W) of the watershed from Figure 4.1. Estimate the

surface area of the pond at the elevation at which you expect to

place the crest of the mechanical spillway. Find the acres in

the drainage area. Start on the left side of the table at a

point indicated by the size of the drainage area and its flood
h-5

<0 Q

uj Q:

«

w

POND AREA (ocres)

0.2 0.25 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.25 1.50 1.75 2.0 2.25 2.5 2.75 3.0

STAGE ( feet)

o

70 3.0 2.75 2.5 2.0 1.75 1.5 1.25 1.25 1.25 1.0

60 ;i—1— r

k4/<i«imiim etnnA

r !'

for thie 3.0 2.75 2.50 2.0 1.75 1.5 1.25 1.25 1.0

50 îhart is 3.0 feet 3.0 2.5 2.25 2.25 2.0 1.5 1.25 1.25 1.0

40

^igher values

equire design

)y field engineer.

3.0 2.75 2.5 2.0 2.0 1.75 1.5 1.25 1.0 1.0 1.0

70 3.0 2.75 2.5 2.25 2.0 1.5 1.5 1.25 l.O

60 3.0 2.75 2.5 2.25 20 1.75 1.5 1.25 1.0

50 3.0 2.75 2.5 2.25 2.0 2.0 1.75 1.25 1.0

40 3.0 2.5 2.0 1.75 1.75 1.5 1.25 1.0 1.0 1.0

g

70 30 2.75 2.5 2.25 2.0 1.75 1.5 1.25 1.0

60 3.0 2.5 2.25 2.0 1.75 1.5 1.25 1.0

~ T

— c

50 3.0 2.5 2.0 1.75 1.75 1.5 1.25 1.0 t)e minimum stage

liven by this cttart is

40 3.0 2.75 2.25 1.75 1.5 1.25 1.25 1.0 1.0 1.0 1 .0 foot. If the determined

in

70 3.0 2.5 2.25 1.75 1.75 1.5 1.25 1.0 stage rails oeiowrnisvaiue i

_ use 1.0«.

60 3.0 2.5 2.25 1.75 1.5 1.5 1.25 1.25 1.0

50 3.0 2.75 2.0 1.75 1.5 1.25 1.25 1.0 1.0

40 2.5 2.25 1.75 1.5 1.25 1.0 1.0 1.0

^"^-^..^ Crest of v<g«talive spillway

O

70 3.0 2.75 2.5 2.0 1.5 1.25 1.25 1.0 Freeboard

60 2.75 2.5 2.0 1.75 1.25 \.25 1.0 stoge

Horizontal Cross Section Areo

of Riser siiall be at least 2 times

the Area of the Conduit

^v 50 2.25 1.75 1.5 1.25 lO 1.0 ^ . 1

40 1.25 1.0 1.0 1.0

^Crest of

mechonicol

spillviroy

in

70 1.5 1.25 1.25 1.0

60 1.0 1.0 1.0

50 - ~"

40 1

UlAbrCAMMAI 1^ äKClUtl 1

PRORI FM

Solution

frnm tnhls abowa Ibr

Find R

Runoff

Relief: r

Infiltrat

Vegetal

Surface

equired Stage. Drainage Area 20 Acres. Pond Area 0.7 Acres.

Producinq Characteristics - Weiqhted Values

oiling land average slope 8% 16

on upland prairie soil brown silt loam 10

cover: 100% pasture and woodland 5

Storage: well defined system of small

(drainage ways 13

:gW50 s« 1.75

:gW40 8« 1.25

difference 0.50

Interpolating

^W4s-0.4x0.5-0.20

^W44-Design Stage«1.45

DESIGNATION

OF WATERSHED

CHARACTERISTICS

RUN-OFF-PRODUCING CHARACTERISTICS |

Design Storm« Approx. Qg

100

EXTREME

75

HIGH

50

NORMAL LI'.

RELIEF

(40)

StMp,ru9g«d terrain,with

above 30%

(30)

of 10 to 30%

(20)

Rolling,with overog«

slopes of 5 to 10%

(10)

Relatively flot lend, with

overoge slopts of Oto5%

SOIL INFILTRATION

(20)

No effecHve soil cover,

either rock or thin soil montle of neQiigible infiltration copocity.

(15)

Stowtofokeupwoterclay

or other soil of low infiltrotion copocity, such as

heovy qumbo.

(10)

Normol-, deep loom with

thot of typicol prorie

soil.

(5)

High;deepsond or other

soil thot takes up woter

reodily and rapidly.

STAGE REQUIREMENTS

FOR FARM PONDS

VEGETAL COVER

(20)

No effective plont cover;

bore or very sporse cover.

(15)

Boortofair;clean-culfivoted crops or poor naturel cover; less than 10%

of drainage area undtr

good cover.

(10)

Foirtogood-,obout 50%

lond,woodland,or equivo'

lent cover} not more thon

50%of oreo in Cleo ncultivoted crops.

(5)

9f Good to excellent;obout

M 90%of drainage orea in

or equivalent cover.

U.S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

ROBERT. M. SALTER, CHIEF

REGION : 3 R. H. MUSSER. DIRECTOR

SURFACE STORAGE

(20)

pressions few ondshoHow;

<lrainog«-ways steep and

smoll; no ponds or morshes.

(15)

LOW; well-defined system

of sntoll droinoge-woys;

no ponds or morshes.

(10)

Normol; consideroble sur

foce depression storoge;

drainage system similar

to that of typicol prorie

londs- lokes, ponds ond

(5)

- High; surface-depression

storoge high; droinoge

system not shorply defined; large flood-plein

storage or o lorgc numREFERENCE:

;f<'^*'''Ü^ZS^ ¿C^ TECHmCAL APf^ROVAl.

5M^ iC«-^^i<*/t^^«^*^ 1

mo

of

rshes les«

drainage

than 2%

oreo. morshes. 0ESI6NED DRAWN CHECKED DATE (RAWING NUMBER j

f 3-L-26438

FIGURE 4.1 STAGE REQUIREMENTS FOR FARM PONDS
k-6

producing characteristics (S W). Then read horizontally to

right. Under the colijmn for the size of the pond area obtain

the required stage for the pond.

Where the solution indicates a stage greater than three feet it

becomes a special design and a structure data sheet as given in

Part 2 will be required.

To obtain the difference in elevation between the crest of the

mechanical spillway and the top of the settled fill, add a minimum freeboard of 2 feet to the stage.

c. Example:

Watershed - acres drainage area - 10 acres.

Normal flood producing characteristics (S W-50).

Area of the pond at the crest of mechanical spillway - 0.-^

acre.

The stage will be found from Figure k.l as 1.25 feet. Then

1.25 feet stage plus 2 feet freeboard gives 3.25 feet from

mechanical spillway to the top of the settled fill.

d. Inlet specifications and details for 8- and 10-inch pipe

spillways are given in Figures k.2, k.3, ^.^, or h.'^. (See

pages k-7, k-Q^ I4-9, and li-10.)

e. Outlet specifications and details for 8- and 10-inch pipe

spillways are given as follows:

For reinforced concrete outlet - Figure h.6 (page 4-11)

For plain concrete outlet - Figure 4.7 (page 4-12)

For concrete block outlet - Figure 4.8 (page 4-13)

For a timber support propped outlet - Figure 4.9 (page 4-l4)

f. Anti-seep collars and tile cradling specifications are given

in Figures 4.10 and 4.11. (See pages 4-15 and 4-l6.) If total

length of tile or conduit pipe is not more than 60 feet, one

anti-seep collar will suffice. It should be placed approximately

4 feet upstream from the centerline of the fill. A good rule-ofthumb method for locating anti-seep collars where the total

spillway length is more than 60 feet is to place them at the 1/3

and 2/3 points or slightly above, Anti-seep collars for metal

pipes shall be of the same material as the metal pipe. Metal

pipe should not be cradled.
^'7

HALF HALF

ELEVATION ELEWTlON

FRONT REAR

6'-0"

2'-^"

7roy\^e/formée/

SECTION ON CENTERLINE

QUANTITIES

VOLUME OF CONCRETE /.€ CU. YDS.

TOTAL WEIGHT OF STEELÄ? POUNDS

ScaÁf 3/â''/'-0'

erncf o/'p/pe

/2'c.c.

PLAN

STEEL SCHEDULE

^2^

LENGTH TYPE

3-0'

6-0'

2'-€"

4'-3'

3'-0'

Z'€'

J'-4'

1^

2'-4'

2-5'

0'-9r

2'-4'

J'-4'

3'-4'

/'-9'é'

/ß'-O'

36-0'

5'-0'

é'-G'

/3'-0'

Revised I-¡3-S2

BM TYPES

TYPE 2

2'ra<//(/s

TYPE 3

4 I—^

. ^^'

-1

1

<

!

1

-'^'

' - \.--\

--\

REINFORCED CONCRETE-BOX TYPE

INLET FOR 8" TO .18" TILE OR TUBE

REGIONAL OFFICE

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT, CHIEF

DESIGNED:

CARTOGRAPHIC APPROVAL: TECHNICAL AJ»PROVAL !

DESIGNED: I DRAWN: M' I CHECKED: CHECKED: I DATE' O^ fDRW6. DRW6. NO. \

3-1-/23/3

FIGURE 4.2 REINFORCED CONCRETE-BOX TYPE INLET FOR 8" TO 18" TILE OR TUBE
k-Q

HALF

ELEVATION

FRONT

HALF

ELEVATION

REAR

SECTION ON GENTERLINE

VOLUME OF CONCRETE 2.3 CU. YDS.

PLAN

PLAIN CONCRETE-BOX TYPE INLET

FOR 8* TO 18" TILE OR TUBE

REGIONAL OFFICE

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT, CHIEF

Scaie-Jè'''f''0''

DESIGNED:

AF.Morati

DRAWN:

CARTOGRAPHIC APPROVAL; TECHNICAL APpROVAL:

CHECKED:

AJiMofOfz

DATE

5/24/46

DRWG. NO.

3-L-I2483

FIGURE 4.3 PLAIN CONCRETE-BOX TYPE INLET FOR 8" TO 18" TILE OR TUBE
k-9

5'-<t 2-a

HALF

ELEVATION

FRONT

HALF

ELEVATION

REAR

y\^: Cores /n fñe ca/tcrek b/oc/rs s/io// 6* fi//ei/ wi/ñ concrefe. TAJs concre/e

s/io// Âf fírm/y ^ompecf orou/fi/ f/te re/ûforc)/>^ s/eeA t/Aen f///inç /ñe ó/OCá

cores eac/> floor s/io// s/àfl 4'àe/oi¥ /Ae fop of//je fop coarse of h/ocÂs

to form a consfrocfio/} Jo/nf for saàseçaenf pours. Af /he /op of//re

wo// ^e concre/e sAo/f Ar f/n/shee/ f/e/s/r w///> //)e /op of //re ó/ocÁrs

or /j/ç/fer as //jcf/ea/ecf óy //tepfans.

SECTION ON CENTERUNE

QUANTITIES

VOLUMES OF CONCRETE:

BASE POUR 0.7 CU.YDS.

BLOCKS-CORE FILL OZ " "

MORTAR 003 " "

CONCRETE BLOCKS >-

STRETCHER BLOCKS -?/ EACH

HALF BLOCKS ¡0

CORNER BLOCKS 4 "

OR 40 STRETCHER BLOCKS

REINFORCING STEEL 42.8 POUNDS

ßoffer wa// f/ush

Wff/i end ofp/pe.

HALF HALF

PLAN SECTION "A-A"

/Revised 0-7-^7 LHMe

fi»^/ê0€/ /e-3/-se e.0.

3ca/e íj¡'-/-0'

STEEL SCHEDULE

47

1>

3'-0'

4'-3'

/-9' f-r 30'O'

34-0

BAR TYPES

S/rotghf

* 1 L 2'rtK/iu*

CONCRETE BLOCK-BOX TYPE INLET

FOR 8' TO 12" TILE OR TUBE

REGIONAL OFFICE

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H.H. BENNETT, CHIEF

CARTOGRAPHIC ÏAPH APPROVI^L: APPROVAL: TECHNICAL APPROVAL

DESIGNED: DRAWN: CHECKED: DATE: ] DRWG. NO.

A.r.Mor«1z D.U«<^Noqi«l«i AJ^Morata 6-3-4C 5-L-I2433

FIGURE 4.4 CONCRETE BLOCK-BOX TYPE INLET FOR 8" TO 12" TILE OR TUBE
4-10

NOTE: This inlet may be used only where one section of pipe riser is required

Groc//7c/ JÍ//7<Z

PLAN

/i? o/ £^û ívoi/tzn tv/ra

<5»/ S/£7/S.

3 - ^'x /£'X 4-a

DETAIL OF

FISH SCREEN

¿y^a an/y yv/para .spacr/Z/'ac/

MATERIALS FOR INLET

I-I8"x4' Tongue and groove

reinforced concrete pipe.

0.9 cu.yds. concrete

All other indicated niaterials.

//<zac/iya// anc^ 7?<7S-/?

Ä'acA c/<z/¿7//s //7<z

c//a. i

I.<S

NOTE Hole to be cut in pipe before pouring base.

The pipe should be packed with a dense soil

mixture before cutting to prevent cracking.

The joint between the conduit and riser shall

be wetted and grouted with a sand-cement

mix and formed as shown.

Special sections with a side opening formed

to fit conduit can be obtained from most

pipe manufacturers.

ALTERNATE

SECTION ON t

Using a 18 + 12 T section

of vitrified clay pipe

TRASH RACK AND PIPE RISER FOR

PIPE DROP INLET SPILLWAY

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

I. BENNETT, DIRECTOR

I. MUSSER. DIRECTOR

CARTOGRAPHIC APPROVAL

DESIGNED

U.Po/ß/n

- TECHNK

DRAWN

CYurA

CHECKED DATE OMWING NUMBER

3-L-I23I2

SHEET OF

FIGURE 4.5 TRASH RACK AND PIPE RISER FOR PIPE DROP INLET SPILLWAY
14-11

Fi'// ^/op^s

0®©@Kq /<? ¿>« /yacfrac/ <?s o un//' <yrx:/

SECTION ON CENTERLINE '^fT'^P'^^^TJp.^l^J^ FRONT ELEVATION

efsjo/ya///<:: ^xjoan^/ortja/'rj/

//•//^/r ; i^ ^ -^

(¿) ® © @

WIN6WALL ELEVATION

PLAN

/Vo/ts: Ou/-/ts/-^/p^ ^/io// tbe

Vf/r/'/^/'itc/ c/e^y, or- r-m/n/hr-c«ic/

concf^/-^ ^mi^m/- />/p^, àorjchc/

pc/f^ /r-ort ^cf/t/on/sec/ or

Cas^ iron p/p».

SCALE >'/4 "'/'-o"

STEEL SCHEDULE

j'-C

^-'-Ô'

s'-o"

y-o''

^'-6

a'-c"

<Î''S"

7- 4."

y-o'

/-Û'

2'¿,'

2'-4"

2:-û-

¿ cr

z-â'

a'-â"

2''â

z'-4'

^'-7'

34'-o'

7'-4"

7-/0"

QUANTITIES

VOLUME OF CONCRETE Î.8 OU. YDS.

TOTAL WEIGHT OF STEEL 123.0 POUNDS

BAR TYPES

^2"Radius—^

C

' B

TYPE-3 TYPE-4

S''4 2-0 2-xr â'-d."

/^ S-Á

^'-J" 4-7" O'-S"

Z'-O"

REINFORCED CONCRETE OUTLET

FOR 8" TO 12" PIPE

REGION- 3 REGIONAL OFFICE

US. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

KH. BENNETT, CHIEF

DESIGNED

A. Morotz

DRAWN

A.M.E.

ïTO^^Pyœ APPROVAL' é TgCHNiÇAL AWIOVAL«

SIGNED' I DRAWN- j CHECKED CHECKEDÍ I DATE ' ^ ORWGrNO.

D. Polzin

DATE =

2-23-3f

ORWGfNO.

3-1-12499

FIGURE 4.6 REINFORCED CONCRETE OUTLET FOR 8" TO 12" PIPE
íl-12

R»t Stop»

SECTION ON CENTERLJNE

KS

s— Nota

1 1 [ ^

J <

ñ

[ ]

y>\

JP U - \

/2K «Ö

«r i i

.^^/^ 1 J %

<

PLAN

Note

The pipe ond crocMe are to be ploced os o unit

and to be separated from the CXitiet by o

1/2" bond of premolded ospholtic exponsion

joint fiUer.

QUANTtTIES

VOLUME OF CONCRCTË 2.4 CU. YDS.

ó?"

S'-4'

r

1

k

ff^

Ni

^"^

•^

^

^

'

FRONT ELEVATION

Scale //4"*/'"O"

PLAIN CONCRETE OUTLET

FOR 8" TO 12* PIPES

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

W. H. MUSStW. «wecTow

OAllTpMAPHIC APmOML ^

CHCCKCD

TECHIMOA^ APffOVAL

DATE

228-5/ 3-L-12517

FIGURE 47 PLAIN CONCRETE OUTLET FOR 8" TO 12" PIPE
4-13

Mofe:- T'A« jo/j»« o/ref crat//e /o 6a

p/<reff</ as er *///// 9^7*/ /o Se se/tara/ee/

fro/rr ffre ou//ef^ Jby tr /^jba/raf of

pre/rro/cfet/ erjíjoAr€r/^/c ex/oef/7s/o^

Joi'n^ f/7/er

SECTION ON CENTERLINE

PS- _i _ ^'-S' p-áSliSlx /-^- a-i /'4' \8- /"^ a- S'

(7v - =^ V vi>-^ =»—. N

-^-- ^

1 m 1 id

1 4- 1 1 TJ j \ \ L. 1

0

N»

_, /-S" ¿(?) ^3- J" S" sÇ) /-8- ;j>>î>a

a-0

- 'i^'^^Ji

ELEVATION

ejtpa/fjf'ony'offT/ f/V/er.

PLAN

/ili-arnate- ^eadwaf^ araonà pfpes

can be co/7crffta poi/ree/ ¿rH-er ifte

Sidev^alls hav^ been p/aced /ei^eJ

with i-he i-op of ^/fe ptpe.

Wa/J th/ckneas of 3" o/yaf aaphoJHc Jo/nt T^v/Z^r requ/recf.

STEEL SCHEDULE

'h¥'

3'-3-

P-3"

3-3"

Z7'Ô'

/Z'-O"

i7--Û'

QUANTITIES

VOLUMES OF CONCRETE:

BASE POUR

CORE FILL (BLOCK)

MORTAR

CONCRETE BLOCKS:

STRETCHER BLOCKS

CORNER BLOCKS

REINFORCING STEEL

0 86

O.'ÎO

80 POUNDS

BAR TYPES

% ?

AllJornia 'A" ^/ck.

First course of è/ocks to he Ar/ef />? frea/?/t/

poured concrete S'/CJô.

Corea to J7e f/Z/et/ mfh cancrefe and f/rn?/y

famped around fffe re/aforc/n^ afee/.

ñt the fop orf fhe wa/J f/?e concrete stra// be

troive/ed f/asA mf/f t/re fop of ffre b/ocJda

The marfar a/?a// be /pcrfporf/andcen7enf

fa 3 parfa aond.

AH co/7crcfe JblocJta a/ra// be p/oced in a lá/afer

hath a m/n/mun? of /^ m/'nufea immed/ofe/y

before /at/in^ in fhe we// and fhe corea

s/fo/l be throughly dpr/nk/cd previoua fo

p/acinff fhe concrefe cor^ f///.

ScaJ^:^¿v^-/-O

CONCRETE BLOCK OUTLET

FOR 8"TO 12" PIPES

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

«EG'ON: 3

KH. BENNETT, CHIEF

R H. WiSSER. DIRECTOR

CA5J0a?APHIC APPROVAL

DESMiNEO DR^Mm CHECKED

A. MONATZ Ñ.e.jesKe O.POLZIêê

DATE

a-28-51 3-L-I25II

FIGURE 4.8 CONCRETE BLOCK OUTLET FOR 8" TO 12" PIPE

\k- 15

9'-0'

4'-0' , //'i, 4'-û'

g©-|>-/g'^ 4-\¿)y2^-^2c£.

/Vû/e' Â/7f/-Jee/> Co//ar

s/jo// not àe heated of a

pjpe Jo/nf.

K^ Noie: '/z"premolded composiiion

^ oöphalfic expansionJoini- filler _.

ELEVATION

coverinq en-tire surface of

cradle and pipe where tliey Join

the an+i'^eep collar.

SECTION THRU Ç_ Of PIPE

DETAILS Of ANThSEEP COLLAR

All steel 2 ^

Scale : 1/4"» I'-O"

I /- <?" J

/ /O' 1 /o" i

Ùgp|^^^^^■■:

>*• ^ i\^j:'Xi:'w::i'i ^^

/- 9"

/-(f

'?)#/^'^-^

TYPE 2 TYPE 3

CONCRETE CRADLE

All Steel I" ^

Scale : 1/2"- l-O"

Revised Z-Z8'5I

STEEL SCHEDULE

^/

^

S'-6'

3'-6"

d'-s'

2'-J 2 ff\^ M"^

2'-3'

7-0-

QUANTITIES

VOLUME OF CONCRETE:

ANTI-SEEP COLLAR-EACH /Jß CU. YDS.

TYPE 2 CRADLE-PER LIN. FT. 0.ÓS5 CU. YDS.

TYPE 3 CRADLE-PER UN.FT. 0043 CU. YDS.

STEEL-COLLAR-EACH 6^.0 POUNDS

STEEL-CRADLE-PER LIN. FT. 2.6 POUNDS

BAR TYPES

S/ra/ffÁ/

^^2'rod

CRADLE a ANTI-SEEP COLLAR FOR

BARREL OF IO"PIPE DROP INLET

REGIONAL OFFICE

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT, CHIEF

REFERENCE!

CARTOGRAPHIC APPROVAL: TECHNICAL APPROVAL!

OESWNEDí I DRAWN! I CHECKED: ¡DATE: I DRW6.N0.

A^^ñfi \M/,wan^b^ \c./p.Poi*^in \j-22-46 \3¿/2$42

FIGURE 4.10 CRADLE AND ANTI-SEEP COLLAR FOR BARREL OF 10" PIPE DROP INLET

259293 O - 53 - 6
1^-16

Ö-/0'

tßk>V-/^.c,

A/a-^^-/in//'Sefop ¿:h//o/'

s/70// ryo-^ ¿30' /oco'^e'ey

0/ o /Of'pe jo/ri/.

ELEVATION sTéTION THRU <g OF PIPE

^Nofe • i^jof-^moíd0d composi . _

OSpho/h'c SM-porisiort Jo/n-e-ftf/ff/'

co\^r-iruf »n^-ine suffocm oF croafA»

and fi/'p« ivhtfr-» they jo/n fhe

on^i"S*9p col/or-^

DETAILS OF ANTI-SEEP COLLAR

All Steel ^^

Scole : lA"- 1-0"

©iy^*^.c.

TYPE 2 TYPE 3

CONCRETE CRADLE

All Steel I' 4

Scale : % r-0"

Revised a-Z6 5l

STEEL SCHEDULE

"m 2

3

4

3

é>

7

:M

3-4'

I'-sr

Z^ö'

3'-6'

s-r

2'0'

20-0"

o'-S /'2' 0'&

42'-3''

/-S"

e'-s"

7-0'

4-/-a"

QUANTITIES

VOLUME OF CONCRETE:

ANTI-SEEP COLLAR-EACH / 3

TYPE 2 CRADLE-PER LIN. FT. 0.03

TYPE 3 CRADLE-PER LIN. FT 0.04

STEEL-COLLAR-EACH 63.7

STEEL-CRADLE-PER LIN. FT ^.4

CU. YDS.

CU. YDS.

CU. YDS.

POUNDS

POUNDS

BAR TYPES

5fra/ght

2'rad^

CRADLE a ANTI-SEEP COLLAR FOR

BARREL OF 8" PIPE DROP INLET

REGIONAL OFFICE

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT, CHIEF

CARTOGRAPHIC APPROVAL:

mm 1° A.

TECHNICAL A^OVAL:

^SIGfiED: IDRAWN: [cílCKEDÍ lOATE: fORWS. W.

fl'r.fS^^H \u.Weñkel Wm4nnc.II2-/Ô-45 \3-LI254l

FIGURE 4.11 CRADLE AND ANThSEEP COLLAR FOR BARREL OF S" PIPE DROP INLET
g. All metal pipe shall have watertight joints^ bands, and

connections in accordance with the manufactxirer^s recommendations for watertight pipe lines. Concrete or vitrified pipe

should "be bell and spigot, niimber one grade, free from cracks or

breaks. Joints should be sealed with mortar (three parts sand

to one part cement). All concrete should be proportioned 1:2:4

(one part cement, two parts sand, foiir parts gravel). If a farm

source of sand and gravel is used, the material should be clean

(not over two percent silty material) and well graded. The

presence of silt or clay can be determined by rubbing some of

the sand in the hands. If stains, which feel smooth or silky,

appear on the hand, it is likely that too much silt or clay is

present. The concrete should be mixed as dry as possible, using

not more than 52 gallons of water per bag of cement. Where the

plan calls for reinforcing steel, do not permit the substitution

of old water pipe, wire, or other metal material. Reinforcing

steel, and reinforcing steel only, must be used. Reinforced concrete designs, especially the "thin wall sections" used in pipe

drop inlet structures, are based on the steel having reinforcing

steel characteristics and require that the steel be placed reasonably accurately, as shown on the drawings. Where it is not

possible to get the diameter steel called for in the drawings,

it is possible to use slightly smaller or slightly larger diameters. In this case, however, it is necessary that an engineer

revise the spacing of the bars.

4.-^3 Vegetative Spillway

a. From procedures outlined in Part 3 determine the required

amount of runoff, using a 10-year frequency rain (see Figure

3.1, page 3-2). Then design the vegetative outlet according to

instructions in Part 10, Vegetated Outlets and Watercourses, to

carry this amoimt. of rimoff. The addition of a trickle tube is

usually desirable as it eliminates small flows which might damage the sod. Use a slope of not less than 0.5^ as the minimum

grade of the outlet and a value of not less than 8 feet for the

minimiam width. The depth of flow should not exceed nine inches

at the crest of the vegetative spillway (three inches if the

pond is to be used for fish production). Consideration should

also be given to entrance width of the sod spillway for good

flow conditions. The proper width of the entrance can be determined by using the formiila Q = 2.75 Lh3/2 or written another way

L = Q divided by 2.75h3/2^ where L is the entrance width of the

channel and h is the assumed depth of flow at the entrance to

the channel. Simplifying the formula given above:

For entr€uice flow 0.75* deep, L = O.56Q

For entrance flow O.5O' deep, L = 1.03Q,

For entremce flow 0.25^» deep, L = 2.92ft

If the calculated width at the crest of the vegetative spillway

is greater tha the width of the channel below, then the rate of

convergence should not be greater than 0.4 foot per foot of

length as measured along the centerline of the channel. See

example in Figure i*-.12 (page 4-l8) .
4-18

SPILLWAY WIDTH REDUCTION

14.0'

z

Crest

«

DIRECTION OF FLOW ^

l3.5*-8*=5.5' 5^ = 13.75 or 14'= length of spillway

required to accomplish the desired reduction in width

FIGURE 4.12 VEGETATIVE SPILLWAY ENTRANCE

k.kh Fill

a. The top width of the fill is generally governed by the construction equipment used. For small farm tractors a minimum

width of 6 feet is permissible. Ordinary earth moving equipment

will require an 8-foot top. If it is to be used as a roadway,

this should be increased to at least 12 feet.

b. Side slopes of the fill should not be less than 3:1 (three

feet horizontal to one foot vertical) on the pond side, and not

less than 2:1 on the opposite side.

h.k"? Freeboard

a. A minimum of 2 feet of freeboard should be allowed between

the crest of the vegetative spillway and the top of the fill.

k.k6 Water Supply Pipe

a. A water supply pipe with a minimum diameter of 1-^" should be

used. A smaller pipe tends to clog.

b. Some form of filter should be used on the upper end of the

supply pipe.

c. A method of draining the pipe below the shut-off valve on

the fill should be provided to prevent freezing,

d. Where the pond is to be stocked with fish it may be advisable

to increase the size of pipe to allow for draining the pond.
4-19

k.kl Eecord of Design

a. Fill in all pertinent information and calculations in duplicate on the farm pond data sheet^ Figure 4.13^ page V20. One

copy is for the coopérâtor and the other is filed with the office

copy of the farm conservation plan.

4.50 STAKING

1^.51 Fill

a. Stake the centerline of the fill and core trench. In most

cases this will be the same centerline. Place top width stakes

at each end of fill with reference stakes beyond the disturbed

area.

b. Set toe of fill stakes (see Part 1,52).

Í1-.52 Vegetative Spillway

a. If a natural spillway is available^ it should be used. ¥here

this is not the case, centerline and cut stakes should be set for

constructing the spillway.

4.53 Mechanical Spillway

a. Set centerline and grade stakes for the tube; set location

and elevation stakes for the inlet and outlet, and location

stakes for the anti-seep collars.

4.54 Water Supply Pipe

a. Set alignment stakes for supply pipe and location, and elevation stakes for the inlet and filter. Set stakes for location

of anti-seep collars, spacing them as shown on the Farm Pond

data sheet (Figxire 4.13), These will be I6 to 20 feet apart.

4.60 CONSTRUCTION

k.6l Clearing Fill Site, Pond, and Borrow Areas

a. Clear all trees, shrubs, and other obstructions from the

pond area. Also remove all trees, stumps, other vegetation, and

highly organic soil from the fill and borrow areas, placing it

where it will not interfere with equipment operation. This latter material should be used as a top dressing to complete the

fill and assist in establishing vegetation.

k.62 Core

a. Excavate the core trench to a minimum depth of three feet

and a minimijm bottom width of four feet, or to the more impervious material underlying the base of the dam. Excavate the core

trench along the centerline extending the full length of the dam.
o

c

>

O

J>

X

m

tat»d

^ TOD of sotted fill . . III. _i unre

Crest of yeç6

X. j * t. 1 spillway El» - ; ^'*^ Crest of mechanical 1 1 Draw typ« and site \ Ikb. FJ// ¡in» (approx.) of outlet

section indicating

apron or outlet pip» ^ V4- inv»rt »Itvation

~-,Z:~"«'^i^_4.,^_4.^^...^ Original groundl/ne^--^

\

^„^ Site preparations 3 ^\^ ^ **"*«^ 1

irz::^'^ ""A^1"*JÍ"'I-11/VÍ. "^' rValv» wall invmrt Flav J^^\^ZL

^„„--'-''''''^ cations as shown on ^'\.

^.---'''^ Std.Dwg.3-L-726l ^

/ Stock tank~K rFloat valve

y^-yr-inv»rt El»v.

l-v^ <r-^

^¡¡¡¡¡^fKmmmm metal pip» is used 'j , .J ..f "'—^"^^^^^^^^^

nclH

1

Jnion-^. "'^-^^^^^^

^/ffir swpp// infak«

indicate typ» dimtnsof propasad filt»r

=t

Cone, collars ^ Cor» tr» Valve Tee-^

Extend to a

\—A

LONGITUDINAL SECTION SHOWING WATER SUPPLY SYSTEM

Inlet Standard Drawing Cradle 3 Collar - Standard Drawing Outl»t Standard Drawing

^^ *" - No.

Numbar and locationis) of collar(s) to b» d»t»rmin»d by field engineer

1 OKirsiTiiniKiAi <%frr.TinKi

\. ALONG GENTERLINE OF MECHANICAL SPILLWAY

<

>

Vaaatatmd soillwav 1

y\ /\ / \ / \

/ \

1 / \

\ ^

'^

1

/

\

'

/ NOTECROSS-SECTION ALONG CENTERLINE OF FILL

(show soil borings)

1 BILL OF MA^

-WATER SUPPÜ

rERIALS COOPERATOR SEC. .T. _..!».

COOPERATING WITH

COUNTY STATE

SURVEYED- DATE

/ 'between arrowheads.

/ Draw (not to scale) all necessary

f SYSTEM-

\ / SIZE SI¿E

PIPE FT VALVES EACi

3WS EACH UNIONS EAC»

PLINGS EACH TEES EACt

> OR PLUGS—EACH FLOAT VALVE_EAC

ER BASE AND COLLARS CONC CU.YDÎ

-MECHANICAL SPILLWAY-

= KIND SIZE IN. LEN Fl

1 \ / 1 \ / ^riL";;i'i"L":r.'í^:r iTw-ry:'':;''" GALV \

\/ v This dqta^ sheet shall be used only for p^y

1

1

r.

FARM POND DATA SHEET

1 /vörf.

7»nt»rlin» of pr»s»nt ehannal

{

"""' c y./«/;. CAP«

1 /Vo/ V»g»tat»d spillway 0ESI6I

DRAINAGE AREA

POND AREA A

STRUCTURE CAR _

CONSTRUCTED BY_

^ DETAILS U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H.H.BENNETT CHIEF 1 « « » mtchanicaf spillway^, ^ ^, 1

\

ACRES, RUNOFF C.FS. p.pp

SRES, POND CAR AC. FT '^"^'^ r

CONC. CU. YDS. REINF. LBS>. CONO. BLKS

V»g»tat»d spillway that is not r»quir»d should \. J>

b» draftad out \...^^ ^^

ÍEL

LET

REPOR T: TAT ^1

^

'^itc^.. 1 TECHNICAL APPROVAL

1 ^

Dl AkI ^ CEM FWT ç:Ar.K<: PARTH FII I P.II vn

ESIGNEJ DRAWN CHECKED DATE DRAWING NUMBER

1 , nii^— TOT .SBS»s »— —j_-L L-_l TTL.-5^i-SHEET

NUMKK

SL_J

ro

o
if-21

Be siire the side vails of the core trench are cut to slope no

steeper than 1:1 to Insure adequate bond with the foundation

material. The core trench should be backfilled with the most

impervious material available.

4.63 Mechanical Spillway and Water Supply Pipe

a. An inspection to insure proper construction should be made

during the time that the mechanical spillway and the water

supply pipe are being installed.

b. The water supply pipe should not be laid \intil the core

trench is backfilled to the elevation of the pipe. It is important that the soil surrounding the entire length of the pipe and

the anti-seep collars be well compacted with impervious material.

The anti-seep collars should be plain concrete, 2 feet by 2 feet,

and 4 to 6 inches thick.

c. The mechanical spillway should be constructed on undisturbed

soil. Extreme care should be exercised in cradling in accordance with the details found on Figures ^.10 or ^.11. All Joints

must be completely watertight and the soil carefully backfilled

and compacted along the entire length of the pipe, around the

anti-seep collars and around the inlet and outlet.

d. A trash rack around the mechanical spillway must be constructed by setting four posts spaced eight feet apart about the

axis of the inlet, on which woven wire is placed. The lower

edge of the wire should be at least six inches below the normal

water level and extend in height to the crest of the emergency

spillway. See Figure ^.5 for details.

k.6k Fill

a. The most impervious fill material should be used in the core,

the next best on the pond side of the fill, and the least impervious on the lower side of the fill. Fill material should be

laid in thin, even layers, not over eight inches thick. Each

lift shall extend over the full width of the dam. If a bulldozer is used to build the fill, frequent trips should be made

lengthwise of the fill to even off the material and aid in compaction. Frozen material shall not be used nor shall the fill

be placed on a frozen foundation. Do not use dry material. The

moisture content of the fill material should be such that when

it is kneaded in the hand it will Just form a ball which does

not readily separate. Further information on fill material is

given in paragraph i|-.22 e.

b. After the fill has been built to required height add an

additional 5?t of the height for settlement. The fill should be

covered with the top soil removed in the scalping operation in

Paragraph k,6l.
il--22

c. All of the fill except the upstream part below the water

line should be limed if necessary, fertilized, seeded with a

good grass mixture, and mulched with manure or straw. The borrow areas above the water line should be leveled and receive the

same treatment.

d. The pond, fill, and a reasonable area adjacent should be

fenced to exclude livestock. An entrance should be provided for

mowing of the fill and other maintenance operations.

4.65 Planting

^a. The pond area should be planted with appropriate shrubs and

trees. Wildlife packets may be used.

il-, 70 MAINTENANCE

Í1..7I Fill and Vegetative Area

a. The fill, the vegetative spillway, and, if possible, a strip

20 feet wide around the pond should be kept free from rank vegetation. Maintenance applications of lime, fertilizer, and seed

should be made as needed to maintain a good vigorous sod.

b. Encourage the farmer to inspect the fill frequently and

repair any rodent or erosion damage. If signs of excessive

seepage are discovered the engineer should be consulted for

recommendations.

il-.72 Other Maintenance Requirements

a. Keep mechanical spillway and trash rack free from debris,

b. Eeplace dead trees or shrubs around the pond area with new

planting stock,

c. Inspect and keep fence in repair.

•i^-H-d. If pond is stocked, fish pond heavily.

e. Keep all trees and shrubs off the earth fill and remove any

woody growth that takes root.

References:

«Biology Handbook and appropriate job sheets.

««Biology Handbook.
5-1

PAET 5

SPRINGS^ AM) HYDRAULIC RAMS

5.10 GENERAL SPRINGS

5.11 Definition and Types of Springs

a. Springs are places where, without the aid of man, water

flows from rock or sand onto the land or into a body of surface

water.

b. That portion of precipitation which percolates into the

ground is called ground water. Ground water may be divided into

two zones - saturated and unsaturated. The surface of the saturated zone is known as the water table. Ground water in the

unsaturated zone moves downward with a pull of gravity, but

water in the saturated zone moves horizontally and down gradient

with the water table. An outcrop of the saturated zone produces

a spring.

c. Different types of springs are illustrated in Figure 5.1.

(See page 5-2.)

5.12 Dependability

a. The perched or contact spring is frequently the least

dependable because of limited storage that may be available, and

the artesian type usually affords the most dependable supply.

However, this does not always hold true. The dependability of

springs is difficult to estimate because of the many variables

that affect the source of supply. The type of spring, conditions

found after an exploratory excavation, and local information as

to the past behavior of the spring are all factors that should

be considered. Sound judgment must be used to eliminate the

expensive development of springs that may soon go dry. Where

possible, the flow of springs should be measured to determine

how nearly it will meet stock water or other requirements.

5.20 DEVELOPING A SPRING

5.21 Perched Depression Spring

a. In the development of this type of spring it is often necessary to provide a means of picking up or collecting water from

several outcrops and leading it to one central point of concentration to provide an adequate supply (Figure 5.2, page 5-3).

This is especially true in developing hillside springs. The

collection trench or gallery is usually dug just above the line

of seepage and excavated to a depth that will intercept the

»Adapted from material given in Engineering Handbook. USDA-SCS, Region V.
5-2

A. PERCHED OR CONTACT SPRING ON SIDE HILL

JPEBPUÊS.

B. STREAM DEPRESSION

SPRING

J^ ' ' '•.•»/ VIM.PERVÎOUÇ. LAYERíí'i :, ,

^Vt>\\ ••' !•. * - ". -^ * \ .WATER T*g'dí3iÍj;¿J=l-jff|^

l^^îlIl^J??l'?^-^.^^-^'-'"^^'^^^'^^^^•~>'^•'^^^^^^ WATER TABLE-

./ » \ It"^

C. ARTESIAN SPRING' .WlÊ.«v»oo| '¿Ç^^î^

nSSURE OR BREAK

D SPRING FLOWING FROM

CAVERNOUS ROCK

FIGURE 5.1 TYPICAL TYPES OF SPRINGS

water-bearing strata. In some cases it may be necessary to follow the sand veins into the bank a short distance to remove any

obstructions so a sufficient flow is obtained. The trench is

usually excavated about two feet wide to receive the collectors

and for ease of digging.

b. The collector may consist of clay tile or perforated pipe

laid in graded gravel and sand, or it may be simply a trench

filled with graded gravel and sand. In the construction of the

collector it is good practice to tamp impervious clay in the

downstream side of the trench, as illustrated in the "Collector

Detail" in Figure 5.2. The clay core is tied in with the impervious material below to intercept the water and cause it to flow
5-3

Pervious material

collector v

Close ends of perforated

collector

,Water tight

y'

To tank

Place pipe at uniform grade

to prevent airlock

SECTIONAL ELEVATION OF COLLECTION SYSTEM

iipp«

Tamped clay

4" Clay tile

6" Sand graded to gravel

DETAIL OF COLLECTOR

Section AA

^Located to pick up all seeps

Fence out collection system

where necessary

-A Spring box may be built as a part

of the collector woll. See detail.

Where woter emerges ot one point in

sufficient volume, a spring box Is all

that is required.

- Collectors may be tile,

perforated,pipe or grovel

PLAN

Collectors

Extend walls for

enough to provide

on adequate cutoff.

Spring box

Outlet pipeT

PLAN OF SPRINO BOX USED

WITH COLLECTION SYSTEM

FIGURE 5.2 SPRING COLLECTION SYSTEM

laterally to the point of collection. Under some conditions

sand points may be driven into the satiirated vein to serve as

collectors,

c. The head wall or cut-off is usually constructed in the shape

of a large V with the apex at the lower side and the wall

extending hack into the banks to prevent the water from going

around the ends (Figure 5.2). The wall should be at least six

inches thick if concrete is used, and should be carried deep

enough to prevent underflow. Rubble masonry^ clay, or other

impervious materials may also be used. Eock and graded gravel

should be placed above the cut-off wall to collect what silt may

be deposited and to direct the flow into the outlet pipe.

d. A spring box may be incorporated in the apex of the V-shaped

wall. It has the advantage of making the spring more accessible, permitting maintenance without disturbing the system as a

whole.

5,22 Artesian Spring

a. This is usually developed by enlarging the mouth by removing

obstruction. The flow can then be collected by one of the various systems illustrated in Figures 5.2 and Figiore 5.3 on page

5-^.
3-k

Delivery pipe

Removeable Covers -

Place earth over

box to depth required

to prevent freezing.

Droin for use

in winter or

to work in box.

Stock Tank approches

should be kept dry.

Tank may be of different

sizes and shapes.

PLAN OF GUARD AND TANK

Place gravel or

rock at tank

approaches to—

afford a firm

foundation.

NOTE: Spring box may be constructed

of concrete,metal culvert or o barrel.

Use type of collection system required

to fully develop spring.

Place oil pipe below frost line.

Place pipe on

uniform grade

to prevent air

locks.

Metal, concrete

or wood tank.

Place coupling here to

permit tank to be drained

by removal of riser.

Protect end

with rock

Tee may be ploced here and horizontol pipe

extended outside tank base and plugged. Removal

of plug will permit flow to by pass tonk.

SECTIONAL ELEVATION

RGURE 5.3 SPRING BOX AND PIPE ARRANGEMENT

5.23 Spring Flowing From Cavernous Eock

a. This type of spring is generally developed by constructing a

spring box around the seep or opening in the rock where the

water outcrops.

5.2^1- Spring Boxes

a. In the event that the spring box is used with a collector

system, the upper wall should have openings or be constructed of

some porous material so that all the water collected by the

galleries can enter the box. Spring boxes for springs not

requiring a collector system may or may not have a porous upper

wall, depending upon the spring. In the case of springs coming

out of a rock ledge, the sides of the spring box are frequently

tied into the rock wall which serves as the upper side of the

box.

b. Spring boxes may be constructed of monolithic or pre-cast

concrete. Metal culvert sections or oil barrels may also be

used. Wood spring boxes are not generally recommended, as their

life is short. All spring boxes must be covered with a tightfitting top to prevent any dirt or debris from getting inside.

In case the spring is used for domestic water supply, the cover

must be water-tight and the spring protected against any possible

source of contamination. In cold weather the spring box and^

appurtenances should be covered with earth to a depth that will

prevent freezing.
5-5

5.25 Delivery Pipes

a. An important part of the spring development is the arrangement of the delivery and overflow pipe layout (Figure 5.3).

Experience indicates that a minimum pipe diameter of 1-^ inches

should be used where the grade is over one percent. Where the

grade is between 0.5 percent and one percent^ a l¿-inch minimum

is recommended. Grades \mder 0.5 percent require a 2-inch minim-um pipe. Grades less than 0.2 percent are not recommended.

When pipe sizes smaller than those recommended are used^ there

is a tendency for them to become clogged with foreign matter,

and they are difficult to clean.

b. The pipe should be laid carefully on a continuous imiform

grade. Sags or high spots usually create air locks which may

stop the flow. They also reduce the velocity of flow. Pipes

should be laid below the frost line and covered to prevent

freez ing.

c. The pipe leaving the spring box should be placed at least

six inches above the floor to provide a silt trap. A watertight connection must be made where the pipe leaves the spring

box or goes through a cut-off wall. A union should be placed

on the pipe outside of the wall to permit easy removal of pipe

sections.

d. Wlierever possible, the outlet pipe should be placed at such

an elevation that a head of water is not created on the spring.

An increase in head will result in a corresponding decrease in

the rate of flow, and in the case of a weak spring, may cause

the seeps to change their path of flow.

e. The pipe connection with the water tank may be accomplished

in a number of ways. The practice of bringing the pipe under

the tank and vertically through the bottom is usually considered

the most desirable where the tank is to be used during freezing

weather. It has also been found beneficial to have the inlet

and outlet pipes fairly close together, near the center of the

tank. Even though the water freezes around the edge of the tank,

it will tend to stay open at the center. Figure 5.3 illustrates

a good method of bringing the delivery pipe into the tank as

well as a method of bypassing the flow underneath the tank.

5.26 Protection

a. Springs frequently occur at points that are susceptible to

flooding during periods of high run-off. Protection should be

afforded to the spring and its appurtenant structures to permit

use without continual maintenance. Diversions properly located

will afford protection in many instances. The spring itself

may be developed so that flood flows passing over the top will

not cause damage. The tank should be set above the flood water

level at a protected point by using a long delivery pipe placed

at proper grade.
5-6

5.30 GENERAL, HYDRAULIC RAMS

5.31 Definition

a. The hydraulic ram is a simple mechanical device, automatic

in operation, for raising water by water power.

^ b. The ram is suitable for supplying water for stock watering

purposes and to meet other water supply needs about the farm.

It is to be noted that the ordinary hydraulic ram actually

delivers only a small amount of the total water available from

its siipply.

c. It is not intended here to give sufficient information to

enable one to work out all the design details of a particular

site, but rather to arrive at the possibilities of using the

hydraulic ram. Manufacturers of rams have information available

on their respective products which will enable a definite choice

of size of ram and price to be paid.

5.40 OPERATION

5.J^1 How the Hydraulic Ram Works (See Figure 5.4 and 5.5, page 5-7)

Briefly, this is how a hydraulic ram works. Water from the

supply flows down the drive pipe to the ram, thus developing a

certain power due to its weight and movement. It flows thro^agh

the outside valve of the ram imtil it reaches a certain velocity,

whereupon the valve closes. The coliimn of water continues on

through the inside valve into the air chamber. When the pressure

in the air chamber equalizes and overcomes the power in the

coliamn of water a re-bound takes place which closes the inside

valve and opens the outside valve, allowing the water to start

flowing again and the entire process is repeated. It is repeated

from 25 to 100 times per minute, building up pressure in the air

chamber, which in t\irn forces water through the delivery pipe to

the place where it can be used.

5.50 DESIGN

5.51 Information Required

When the water supply is limited, a ram must be selected which

will operate with the minimum quantity of water available; where

there is an abundant water supply the size is governed by the

quantity of water needed per day.

In deciding what size ram to use the following information must

be obtained:

(1) The nimiber of gallons per minute which the spring,

artesian well, or stream will deliver.
5-7

RESERVOIR-.

DRIVE PIPE TILE

DRAIN

GATE VALVES'

RGURE 5.4 SKETCH OF TYPICAL RAM INSTALLATION

INSIDE OR 1 1 ^^^

CHECK VALVE l-CHAMBER

OUTSIDE ^p^L

VALVE «*^^^^

^6^ÉÈ^^\ DELIVERY)

i ^ wm ^ /^^^^^X PIPE

Cf !•" m^^ß^

^SUPPLY PIPE

\. ,i

FIGURE 5.5 DIAGRAMMATIC SKETCH OF RAM
5-8

(2) Number of gallons per 2i|--hour day desired from the ram.

(3) Available fall in feet from the source of water to the

ram.

(k) Elevation to which water is to be raised above the ram.

(5) Pipe line distance from ram to point of discharge.

(6) Pipe line distance from the source of water to the ram.

m

This information will also be required by the company from whom

the ram is purchased.

5.52 Determining Size of Rams

A formula for calculating the number of gallons of water delivered per hour to a given point is as follows :

D - V X F X ^0

E

D = gallons per hour,that the ram will deliver.

V = gallons per minute of supply water available.

F = fall in feet.

E = vertical elevation in feet that water is to be raised.

Similar information can be obtained by referring to the following table:

GALLONS OF WATER LIFTED BY HYDRAULIC RAH PER GALLON

RECEIVED FROM SOURCE

Fall

in

Height Del ivered (in feet)

Feet 12 18 24 30 36 48 60 72

2 0.1

1^ 0.18 0.15 0.1

6 0.33 0.2 0.17 0.13 0.1

8 0.42 0.28 0.2 0.17 0.15 0.1

10 0.5J+ 0.36 0.27 0.22 0.18 O.U 0.1

12 0.67 O.kk 0.33 0.26 0.22 0.16 0.13 0.1

•i^From Farmers' Bulletin No. 1978 Safe Water For the Farm.

5.53 Length of Drive Pipe

The length of drive pipe to be used should be in direct relation

to the vertical elevation. It is equal to the vertical elevation

plus enough to overcome friction loss in the delivery pipe. For

a good approximation use the vertical elevation plus 10*^ to 20^

(to allow for this friction loss).

References:

Rife Ram & Pump Works, Wayneboro, Virginia

Gould Pump, Inc., Seneca Falls, New York

Deming Co., Salem, Ohio

Farmers' Bulletin No. 1978, Safe Water for the Farm
6-1

PAET 6

WELLS^

6.10 GENERAL

6.11 Types of Wells

There are three general types of wells - dug^ driven, and

drilled. The method used in constructing a well depends largely

on the depth to which it must be carried, the elevation of the

groimd water table, and the nature of the material encountered

in the hole,

a. Dug wells are constructed by digging down to water-bearing

strata. The open excavation is usually circular in shape and

from three to five feet in diameter. Before modern well drilling equipment was available, the dug well had extensive use.

However, under present-day methods, driven or drilled wells are

in most cases far more satisfactory and economical.

b. A driven well is only adapted to relatively shallow depths.

In sandy soils, wells have been driven to depths up to 60 feet.

The three most common methods employed in sinking the well are:

(1) Attaching a sandpoint to the end of a pipe and driving

it to the required depth.

(2) Forcing the pipe down by removal of material with a

sandbucket or pump.

(3) By Jetting the material away from the end of the pipe

to permit it to penetrate to the desired depth.

c. A drilled well is suited to any type of material or depths.

It is constructed by standard equipment which consists essentially of a derrick, a power plant, and special tools.

This type of well must be constructed by an experienced person

who has the necessary equipment.

6.20 CONSTRUCTION OF WELL

6.21 Factors or Information to be Considered in Locating a Well

a. Locate the well so the natural drainage from barns, chicken

houses, hog pens, feed lots, toilets, etc. are away from the

well, never toward it, to eliminate danger of contamination.

b. Locate the well above floodwater elevation.

«Adapted from material given in Engineering Handbook, USDA - SCS, Region 5.

259293 O - 53 - 7
6-2

c. If feasible, locate the well as near the point of use as

possible. Windmill must be built so it will be 15 feet above

all obstructions within 400 feet.

d. Investigate existing supplies in proximity to well site as

regards depth of hole, quality and quantity of water, and pumping head.

e. Obtain information from local well drillers about wells

drilled in the camnimity.

f. The following State offices are prepared to give information

on ground water:

Illinois - Chief, State Geological Siirvey Division, Urbana

Indiana

Iowa

Michigan

Minnesota

Missouri

Ohio

Wisconsin

6.22 Casing

Head of Ground Water Resources, Division of Water

Resources, Indiana Department of Conservation,

Indianapolis

Director and State Geologist, Iowa City

Geological Survey, Department of Conservation,

Lansing

Division of Water Resources, St. Paul

State Geologist, Rolla

Chief Engineer, Ohio Resources Board, Columbus

State Geologist, Madison

a. The diameter of the well or casing is governed by the quantity of water required and by local custom. The exact size of

the casing will be determined by conditions existing at the site.

b. Practically all wells in this Region are cased the entire

depth. The only exception is where the water-bearing stratum is

composed of rock overlain with unconsolidated material. Under

such circijmstances the casing need only be extended to the rock

and sealed.

c. In most cases new casing should be used as the life of the

well is dependent on the life of the casing. Second-hand casing

is only used when the quality is equivalent to that of new pipe.

The casing may be galvanized steel pipe or made of black iron.

Second-hand pipe previously xised in connection with gas or oil

developments is not satisfactory, regardless of the condition of

the metal itself. Such pipe may taint the water to a degree

that it is not usable. Pertinent data in weights and diameter

of types of pipe used for well casing is given in the following

table:
6-3

WEIGHTS AND DIMENSIONS OF PIPE AND CASING

Me i gift Per Foot Threads

Size Diameters Tliicl«-

ness

Plain

Ends

Til read s &

Couplings

Per

External inci) Internal

Standard Pi|^e - Blacl( and Galvanized

3A 1.050 .824 .113 1.130 1.134 14

1 1.315 1.049 .133 1.678 1.684 11^

111

111

111

l-l/l^ 1.660 1.380 .140 2.272 2.281

1-1/2 1.900 1.610 .145 2.717 2.731

2 2.375 2.067 .154 3.652 3.678

2-1/2 2.875 2.469 .203 5.793 5.819 8

3 3.500 3.068 .216 7.575 7.616 8

3-1/2 4.000 3.548 .226 9.109 9.202 8

k 4.500 4.026 .237 10.790 10.889 8

if-1/2 5.000 4.506 .247 12.538 12.642 8

Standard B1acl( Well Casing

2 2.250 2.050 .100 2.296 2.340 14

2-1/1^ 2.500 2.284 .108 2.759 2.820 14

2-1/2 2.750 2.524 .113 3.182 3.250 14

2-3/i^ 3.000 2.768 .116 3.572 3.650 14

3 3.250 3.010 .120 4.011 4.100 14

3-1/i^ 3.500 3.250 .125 4.505 4.600 14

3-1/2 3.750 3.492 .129 4.988 5.100 14

3-3/i^ 4.000 3.732 .134 5.532 5.650 14

k 4.250 3.91^ .138 6.060 6.200 14

J+-1/4 4.500 4.216 .142 6.609 6.750 14

4-1/2 4.750 4.460 .145 7.131 7.250 14

6.23 Well Cover

The top of the well should be sealed by means of a concrete slab

(Figure 6.1, page G-k), The slab is made large enough to serve

as a base for the piamping equipment. The casing should extend

about 12 inches above the normal ground surface and should make

a watertight connection with the base which is usually made about

six inches thick.

6.2h Drop Pipe

All drop pipe should be standard galvanized pipe. It is advisable to use a drop pipe having an internal diameter larger than

that of the cylinder or working barrel to permit removal of the

valves for repair without pulling the drop pipe. The drop pipe

should extend far enough into or below the water-bearing strata

to permit the well to be pumped continuously at capacity without

danger of exposing the suction.
6-4

CLOSED TpP PUMP

Stuffing Box

Note:

Pump stond and bose must be in

one piece or joined by threaded

connection.

Extend meta) sleeve for more above

surface of slab.

Note:

Weep hole to be placed below

frost depth to provide on

antifreeze

FIGURE 6.1 DRILLED WELL AND PUMP INSTALLATION
6-5

6.25 Cylinder

The size of the cylinder is determined by the diameter of the

veil, pumping rate, well depth, and size of wheel if a windmill is \ised. It is good policy to design the pumping unit to

produce from two to three times the total daily requirements in

2k ho\irs, particularly when wind is used as a source of power.

Always select a cylinder having a capacity somewhat less than

that of the well to permit continuous pumping without danger of

lowering the water to the point where the suction is exposed.

The two following tables can be used as a guide in selecting the

size of cylinder for any particular well. When a hand p\jmp is

used, it is desirable to install as small a cylinder as possible,

because the larger the cylinder the more power is required to

operate the pump.

LARGEST SIZE CYLINDER THAT MAY BE USED IN VARIOUS SIZED WELL CASING

Size of

Casing Largest Size of Cylinder and Type

(Inches)

2 1-3/8" Brass Body Flush Cap Cylinder

2-1/2 1-7/8" Brass Body Flush Cap Cylinder

3 2-1/2" Brass Body Flush Cap Cylinder

3-1/2 2-1/4" Brass Lined Cylinder OE

3" Brass Body Flush Cap Cylinder

k 2-1/2" Iron or Brass Lined Cylinder^

3-1/2" Brass Body Flush Cap Cylinder

4-1/2 3" Iron or Brass Lined Cylinder,

4" Brass Body Flush Cap Cylinder

SIZES OF CYLINDER ADAPTED FOR DIFFERENT PUMPS ACCORDING TO DEPTH OF WELL

Depth of Hell - Feet

25 SO 76 100 125 ISO 200

^ Size of Cylinder inches

1. Light hand top lift pump

2. Medium hand top lift pump

3. Heavy hand top lift pump k 3¿ 3-1 3 2¿

k. Light windmill top lift pump

5. MediTjm windmill top lift pump 3¿ 3|- 3 2¿ 2

6. Heavy windmill top lift p\mip ^ 3^ 3¿ 3 2¿ 2¿
G'6

6.30 SELECTION OF PUMPS^

6.31 General

In selecting a piamp consideration must be given to the capacity,

location of the well, and type of power available. The foiir

most common types of pijmps are the pliinger, centrifugal, turbine, and ejector pumps.

6.32 Plunger Type Pump

This type of pump is adapted to practically any depth of well

and at depths exceeding 65 feet it is likely to be the most

efficient type. It is positive in action and of relatively

simple construction; and it is suitable for hand, windmill, or

any other type of power operations. However, this type of pump

must be set directly over the well, which may be objectionable,

and it is subject to vibration and sometimes noisy.

6.33 Centrifugal Type Pump

Centrifugal pimips are efficient in the higher capacities but for

small capacities 10 gallons per minute or less, their efficiency

is not so high as that of the plunger pumps. It is usually not

practical to adapt them to Jobs requiring these small volumes of

water. They are at their best when p-umping for irrigation, city

water systems, and other large volumes.

6.3^- Turbine Type Pumps

Turbine pumps, as used in domestic water systems, are selfpriming. Their smooth operation makes them suitable for installing where noise and vibration must be kept to a minimum. This

type of pump requires a well of relatively large bore.

6.35 Ejector Pumps

Ejector pumps are of simple construction, quiet operation, and

suitable either for deep or shallow wells. They are most

efficient when the lift is between 25 to 65 feet, but it will

operate with lifts of 120 feet. However, they are not usually

reconmiended for wells where the depth to water is more than 85

feet. The pump need not be set directly over the well and it is

especially suitable for use with pressure systems.

6.ho POWER REQUIREMENTS

G.kl Electric or Gasoline Engine

The following table gives the approximate H.P. required to piamp

a given quantity of water under a given head by electricity.

Always select a motor that is overpowered. The capacity is

based on kO strokes per minute. To find the capacity of any

size cylinder with less than ^¡0 strokes per minute, deduct l/40

part of the capacity given for each stroke less than kO strokes

per minute.

«Adapted from Farmers' Bulletin 1978 "Safe Water For The Farm.'
6-7

CAPACITY OF DIFFERENT SIZED CYLINDERS AND HORSE POWER REQUIRED FOR

DIFFERENT TOTAL HEADS - SINGLE ACTING PUMP

(Assumed Efficiency Factor 0.33-1/3)

Size

Cylinder

Length

Stroke

Stroke

Per

Gallons

Per Horse Power Requi red for Total Head

Inches Inches Minute Hour 25' 50' 75' 100' 125' 150' 200' 400'

2 6 40 196 .065 .13 .20 .25 .32 .38 .50 1.00

2 8 40 261 .08 .16 .24 .32 .40 .48 .64 1.28

2 10 40 326 .10 .20 .30 .40 .50 .60 .80 1.60

2-1/^ 6 40 247 .075 .15 .23 .30 .38 .45 .60 1.20

2-l/it 8 40 330 .10 .20 .30 .40 .50 .60 .80 1.60

2-1/^ 10 40 413 .13 .26 .39 .52 .65 .78 1.04 2.08

2-1/2 6 40 306 .095 .19 .29 .38 .48 .57 .76 1.52

2-1/2 8 40 408 .12 .24 .36 .48 .60 .72 .96 1.92

2-1/2 10 40 510 .16 .32 .48 .64 .80 .96 1.28 2.56

2-3/4 6 40 370 .115 .23 .35 .46 .58 .69 .92 1.84

2-3/4 8 40 493 .15 .30 .45 .60 .75 .90 1.20 2.40

2-3/4 10 40 617 .19 .38 .57 .76 .95 1.14 1.52 3.04

3 6 40 440 .14 .28 .42 .55 .69 .83 1. 10 2.20

3 8 40 587 . 185 .37 .56 .74 .93 1.11 1.48 2.96

3 10 40 734 .23 .46 .69 .92 1.15 1.38 1.84 3.68

3-1/4 6 40 517 .165 .33 .50 .65 .82 .98 1.30 2.60

3-1/4 8 40 690 .21 .42 .63 .86 1.07 1.28 1.72 3.44

3-1/4 10 40 862 .27 .54 .81 1.08 1.28 1.62 2.16 4.32

The material is given for general information only, as it is impractical to include enough data to cover all possible types of

installations and determine all the loss of power that occurs

from friction. Always check the motor size selected for a given

installation with a reputable dealer to insure proper fimctioning

of the unit. If a gasoline engine is used for power in place of

a motor, add 50 percent to the ÏÏ.P. required.

6.42 Windmill

The mill should have sufficient power to pump the quantity of

water specified. The following table gives the approximate

quantity of water delivered when the mill is operating in a wind

strong enough to run at its maximum number of strokes. When the

prevailing winds are light or variable, where the wind usually

blows only a few hours each day, or where the exposure is poor,

an oversized mill should be selected. Pumps and cylinders used

with the various sizes of mills should be capable of giving a

clear stroke equal in inches to the diameter of the windmill in

feet; i.e., 8 inches for 8 feet, 10 inches for 10 feet, etc. The

capacities shown in the table are based on the long stroke of the

mills. When the short stroke is used, the capacity should be

reduced about 25 percent. Use of the short stroke is not recommended except under conditions when it is required to fit an

existing pump installation.
6-8

PUMPING CAPACITY OF MILLS

Size of

Cylinder

(Inches)

Capacity Per

Hour

Elevation in Feet to Which Water Can Be

Raised

(Gallons) Size of Mill

6» 8'-16' 6» 8' 10' 12» 14' 16'

1-3/^

1-7/8

2

2-1/lf

2-1/2

2-3/^

3

3-1/i^

3-1/2

3-3/k

k

k-l/k

1+-1/2

k-3/k

105

125

130

180

225

265

320

kko

570

725

• • •

150

180

190

260

325

385

klQ

550

6^0

730

830

9kO

1050

1170

130

120

95

77

65

56

kl

'35

"27

'21

• • •

185

175

liiO

112

9k

80

68

*5Ó

• • •

39

• • •

30

280

260

215

170

140

120

100

88

76

65

58

51

k6

• • •

i(.20

390

320

250

210

180

155

130

115

98

86

76

68

61

600

560

kGo

360

300

260

220

185

160

1^3

125

110

98

88

1000

920

750

590

k90

k2^

360

305

265

230

200

180

160

llfO

It should be noted that the piaiping capacity of the mills in the

table above, varying in diameter from 8 to I6 feet, is the same

with cylinders of the same diameter. The length of stroke

increases in proportion to the size of the wheel, but the number

of strokes per minute decreases; consequently the discharge

remains constant. With the 6-foot mill, which is back-geared

more than the other sizes and has a stroke of only 52 inches, the

quantity of water delivered is about 30 percent less than for the

other sizes. The reduction in capacity for any particular size

of cylinder is compensated for in the ability of the 6-foot mill

to raise water to a greater elevation than its true proportion.

Reference:

Farmers' Bulletin No. 1978 "Safe Water For The Farm"
7-1

PAET 7

CONCBETE AND MASOKRY STRUCTURES

7.10 GENERAL

7.11 General Functions of Concrete and Masonry Structures

a. Concrete and masonry structures are efficient supplemental

control measures in soil and water conservation work. Good vegetative practices^ together with proper land use^ are indispensable in a so\md soil and water management program. But there

are many instances where vegetative measures and simple practices

alone are inadequate to handle a concentration of water. In such

a case permanent structures of masonry and concrete play an

important part in reinforcing or supplementing the other practices,

b. There are also instances where a high degree of safety and

permanence are desirable. Conservation measures may be required

which will be good insurance against loss of life or destruction

of property. Vegetative control measures are subject to the

influences of such uncertain factors as climate, insects, etc.,

and therefore are not too dependable. On the other hand, properly designed and installed structures, of material such as concrete and masonry, are of long life and dependability.

7.12 Information Essential to the Farm Planner

a. The principal component parts of common structures.

b. Common types of permanent structures, their adaptability,

advantages, and limitations, relative costs, etc.

c. An appreciation of field survey information incidental to the

design of permanent structures, as well as the manner in which

this information is developed on structure data sheets.

d. How to make preliminary rough cost estimates of structures.

e. Means of insuring the installation of structures of good

quality and workmanship,

f. Structure maintenance practices,

7.20 COMPONENT PARTS OF STRUCTURES (Figure 7.1^ page 7-2)

7.21 Inlet

Water enters the structure through the inlet, which may be in the

form of a box or a weir in a wall. The box may be straight or

flared, while the wall may be straight, flared, or curved. Vertical walls extending down into the soil foundations under the
7-2

A. INLET

I.DROP SPILLWAY

B. CONDUIT C. OUTLET

I. Straight LNone

g.Curved =H H= 2.Ogee

I.Apron ——

Morris

^'-:M^ 2. and —

')^[:£i:-\f^'1% Johnson

3. Box nl IT

g.DROP INLET SPILLWAY

A. INLET B. CONDUIT C. OUTLET

I. straight -

Upstream

2. side --

flared

3.Flared -

I.Box

2.Pipe

I.Cantilever- TS.

2.SAF —

E

Baffle

type

A. INLET

m.CHUTE SPILLWAY

B. CONDUIT C. OUTLET

I. Straight ll II I.Rectanguiar-fi I.Apron

2.Flared Yf

3.Box ~I r

2.Cantilever3.SAF BB>

FIGURE 7.1 SPILLWAY NOMENCLATURE
7-3

inlet are known as cut-off walls. Their main piirpose is to prevent water seepage under the structure. Similar walls, extending from the inlet to prevent seepage around the ends of the

structure, are called headwall extensions. These walls also protect against burrowing rodents.

7.22 Conduit

The conduit receives the water from the inlet and conducts it

through the structure. It restricts the water within a definite

channel. The conduit may "be closed in the form of a box or

pipe, or it may be open as in a rectangular channel or ogee section. Cut-off walls or anti-seep collars are usually constructed

as an appurtenance of the conduit to prevent seepage adjacent to

it. This insures greater structure stability.

7.23 Outlet

The water leaves the structure through the outlet. Its function

is to discharge the water into the channel below at a safe velocity. The outlet may be of the cantilever (projecting) type, a

simple apron outlet, or an apron with any variation of an energy

dissipâtor to minimize the erosive effect of the water. Cantilever outlets are necessary in locations where the channel grade

below the structure is unstable.

Vertical walls known as toe walls are built around the apron to

prevent undercutting. They are similar in construction to cutoff walls under the inlet. "Wing walls" or vertical walls,

extending from the outlet back into the channel banks, protect

against the swirling effect of the turbulent water as it enters

the channel.

7.30 COMMON TYPES OF STRUCTURES

7.31 General Nomenclature (See Figure 7.1)

a. The three principal types of structures are known as drop

spillways, drop inlets, and chutes. T];iese are further described

with respect to their inlet, conduit, and outlet. Any combination of inlet, conduit, and outlet may be used for each general

type of structure. A spillway for an earth dam consisting of a

straight box inlet, pipe conduit, and cantilever outlet would be

known as a straight pipe drop inlet spillway with cantilever outlet. Figure 7.3, page 7-^.

7.32 Drop Spillways

a. Adaptability - An efficient structure (Figure 7.2, page J-k)

for the control of relatively low heads, normally up to eight

feet.

It can be used effectively for the following purposes:
7-^

FIGURE 7.2 STRAIGHT DROP SPILLWAY

Can hi le ver OuHef

^Top, Settled rill

Cresh oF Structurei

Spillway

Anti-seep Collar

FIGURE 7.3 PIPE DROP INLET
7-5

Outlets for tile and surface vater at upper ends of drainage

ditches. Where the channel width below the proposed structure site is limited^ the box type inlet is most effective.

Eeservoir Outlets

Grade stabilization structures in lower reaches of water disposal

systems; i.e., terrace and diversion outlets.

Erosion control structures, for protection of roads, buildings,

and other improvements against encroaching gullies.

b. Advantages - This is a stable type of structure. The concrete block type structure can easily be built with farm labor,

while the reinforced concrete type usually requires the services

of a contractor.

c. Limitations - The life of many drop spillways is often

shortened by undercutting of the apron and adjacent foundation.

A stable grade below the structure is, therefore, essential to

its stability.

d. Relative Costs - For control of relatively low heads, it is

one of the more efficient types of structures when considered on

a "cubic yard of concrete or masonry in place" basis. For discharges less than 250 c.f,s. the straight drop spillway is generally more economical, while above this capacity the box inlet

type will be more economical.

7.33 Drop Inlet Spillway

a. Adaptability - A very efficient structure (Figure 7.3) in

the control of relatively high heads, usually above ten feet.

This structure type is well adapted to sites providing an appreciable amount of temporary storage above the inlet. It may be

used in connection with relatively low heads, as in the case of

a drop inlet on a road culvert.

Among its uses may be listed:

Outlets for farm ponds or reservoirs.

Erosion control structures in arresting gully heads.

At lower end of water disposal systems.

Outlets for silt detention reservoirs or settling basins.

Roadway structures.

Flood control structures.

b. Advantages - For high heads it requires less material than a

drop spillway under similar circumstances or capacity requirements. It is relatively simple to build.
7-6

Where an appreciable amoimt of temporary storage is available

above the inlet, the design discharge capacity of the structxire

can be materially reduced. Besides effecting a reduction in

costs, this reduction of discharge results in a lower peak channel flow below, and consequently it can be a favorable factor in

problems involving channel grade stabilization.

c. Limitations - Small drop inlets are subject to stoppage by

debris. Effectiveness of this type of structure depends as much

on the supporting earth fill material as on the structure itself.

d. Relative Costs - It is a cheaper structure than a drop spillway under high heads. The relatively low quantity of masonry or

concrete material required in the structure is often offset by

the need for large earth fills.

J.3k Formless Chutes

a. Adaptability - This type of structure (Figure 7.8, page 7-12

and 7-13) is used where low head control and the low range of

spillway capacities (20 to 120 c.f.s.) are required. Its use has

been limited to the southern part of the region because of the

extreme variations in temperature in the northern part. It has

particular adaptability to the control of overfalls at the end of

terrace outlets.

b. Advantages - The spillway is easy to construct. The earth

forming and concrete work can be handled by a small farm group.

An inexperienced group can be trained to install this structure

in a relatively short time. Maintenance and major repair work

is more easily accomplished than on other spillways.

c. Limitations - The use of this structure is limited to sites

that have good, natural \mderdrainage. It must not be used as a

water impounding structure. The life expectancy is not as long

as the other spillways covered in this "Part." Because of the

ease of construction it is often placed at sites for which it is

not adapted.

d. Relative Costs - This structure has the cheapest total installation costs for comparative discharge and head control. Inexperienced labor is usually all that is needed for the job. The

elimination of wall forming is another major saving.

7.35 Fonmed Chutes

a. Adaptability - This type of structure (Figure 7.^;^ Page 7-7)

is generally adapted to the control of high heads where high

discharge capacities are required.

b. Advantages - Sites adaptable to this type of structure

usually present favorable construction conditions, since such

sites are normally dry. It is not as susceptible to stoppage

by debris as the drop inlet spillway. The discharge capacity of

the spillway is not affected by high tailwater or silting below

the apron.
7-7

^>

ite«*"<%

JLP*

'^-W<^-**^'^'*%^V''*'"^^'*^W'* ^"*^NJ^

.^^^á .•^'««w«-«f-«*^*N^*^^^^'*

FIGURE 7.4 REINFORCED CONCRETE CHUTE

c. Limitations - For control of heads under ten feet this type

will usually require more material than the drop spillways.

Chutes should be restricted to site having favorable foundation

conditions. Unstable soils and seepy banks require expensive

under-drainage systems.

d. Relative Costs - Chutes with comparable discharge capacities

nomially require more material than drop spillways under low

heads. For high heads and large discharges the chute is usually

more economical.

7.^0 STEUCTUEE DATA SHEETS AND DESIGNS

7.4l Preparation of Structure Data Sheets. (Figures 7.5 and 7.6,

pages 7-8 and 7-9) (See Part 2)

a. Gully or Channel Profile - This shows the bottom of the gully

or channel, and top of the banks for a distance of at least 6OO
WATEeSHED

a Wafershed Boundary

3suL

Dark

DPAiNAce Ae£A 'eeSAc

/

HYDP0L06/C AND HYDP/\UUC QAJA

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colored, medium to heavy

LOCATION PLAN OF STFUCTUieE:

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fhrough /O'mn Clay Sewer-^ \ J \ \

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D/scHA/?<iE CAPACITY Ç'230c.f.s.

CHECK VELOCITY BELOW 3mocTot?E:

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SOIL CONSERVATION SERVICE

M H BENNETT, CHIEF

REFERENCE

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7-10

feet, both above and below the proposed structure site. In any

event, the profile must be extended at least far enough below

the structure site to be certain that a stable grade exists. The

structure site, location of cross fences, location and size of

tile lines, high water marks, and other pertinent data influencing the structure design are indicated on the profile. This

information is used by the designer in establishing such relative

elevations as top of spillway apron, crest of spillway weir,

extreme top of dam, etc.

b. Watershed Map - See Part 2.50, page 2-12

c. Cross Sections - These are taken at the structure site, and

at regular intervals of approximately 100 feet both above and

below the site for a distance of ^1-00-500 feet. These cross

sections guide in locating the structure with respect to the

center of the channel or gully, establish the relative elevations

of the component parts of the structure, and are a basis for predicting the stability of the channel below the structure. Soil

borings are normally plotted on the respective cross sections as

an indication of channel or structure foundation stability.

d. Location Plan - See Part 2.60, page 2-l4

e. Hydraulic and Hydrologie Calculations - These include calculations of runoff from the watershed, discharge capacities of

the proposed structure and of other existing structures affecting

the design.

7.^2 Standard Structure Data Sheets

Standard "Data Sheet for Formless Chute" Figure 7.7, page J-ll^

and "Data Sheet for Toe WAlls" (Drawing #3-0-26750) can be'used

for these Class E structures. They can be obtained from the cartographic division. Information concerning material quantities

and dißcharge capacities, which are needed in the planning and

design of each structure, are given on Figure 7«8 pages 7-12 and

7-I3, "Formless Chute (Class E Structure)"; Figure 7.12^ page

7-20, "Index Sheet for R/C Straight Drop Spillways" and Figure

7.10, page 7-I6, "Index Sheet for Concrete Block Straight Drop

Spillways." Standard datasheets have design guides listed on

the drawings and these standards should be used when available.

7.43 Structure Design

a. Purpose of Detailed Design - The detailed structure design

develops in detail the over-all plan for the structure as indicated on the structure data sheet. Such items as detailed

dimensions of the various parts of the structure, spacing of

steel reinforcing bars in reinforced concrete, and location of

construction Joints are a few examples of detail.

b. Responsibility for Detailed Designs - Except in rare cases

the responsibility for developing detailed designs rests with

the engineer.
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HAL F ELEVATION

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COOPERATOR

COOPESATÜíG W'.TH

COUHTt STATE-.

SURVEYED

LONGITUDINAL SECTION ON g SECTION C-C

SECTION B-B

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HALF PLAN SECTION A-A

STRUCTURAL DETAILS

Us» 5 inch thicknas$ ofconcrgfe ihrouQhout »xcept os éimtnsioneit oiharwistRtinforeing os indieattd shall be (l) 3/B"f niníorcing stool IZ"e.c. both moys;0r (2) No.Z gauge welded wire fabric 6'c.e. both mays.

(common designation 66-221 Reintocirtg bars or mesh should be lapped one foot at all Joints.

Spillways of this type shall be constructed on solid ground. Seep areas should be avoided or properly drained with a carefully

constructed toe drainage system.

This spillway shall not be used as a part ofo water impouiHling structure.

The disturbed area adjacent to the spillway shall be backfilled, compacted and sodded.

The length (Uof the spillway shall be limited by the amount of concrete that can be adequately mixed, placed and finished

in one days time with the labor and eguipment available or Maximum L'S'-O'

The maximum "»'for this spillway is 6-0'

This spillway is limited to Closs'e"Jobs and use of this data sheet is restricted to this spillway and job approval

classification.

LOCATION PLAN

DATA SHEETS BY DRAWING NUMBER 3-0-18798

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HALF PLAN

HALF ELEVATION

STRUCTURAL DETAILS

SECTION C-C

SECTION A-A

Discharge Capacity of Spillway in c.f.s.

Lffnçfh ofCresf(L) in fee/ 2 4 G Ô

Wffh rto freeboard 30 45 GO 75

wi/h G "freeboard /â ZS 3â 4Ô

NOTESA. Use 5 inch thickness of concrete throughout except

as dimensioned otherwise.

B. Reinforcing as indicated shall be (I) 3/8 "^ reinforcing steel I2"c.c both ways; or (2) No.2 gauge welded wire fabric 6"c.c. both ways, (common designation

66-22). Reinforcing bars or mesh should be lapped

one foot at all joints.

C. Spillways of this type shall be constructed on

solid ground. Seep areas should be avoided or

properly drained with a carefully constructed toe

drainage system.

D. This spillway shall not be used as a part of a water

impounding structure.

E. The disturbed area adjacent to the spillway shall

be backfilled,compacted and sodded.

F. The length (U of the spillway shall be limited by

the amount of concrete that can be adequately

mixed, placed and finished in one day's time with

the labor and equipment available or a Max. L-8'-Cf'

6. The maximum "H"for this spillway is 5'-0"

H. Standard Data Sheet 3-0-18798 may be used for

recording the necessary survey information and

design data for this spillway. If the standard

data sheet is not used this information shall be

placed on the regular P-size data sheetis).

SCALE 1/4"= I'-o"

Concrete Volumes in Cubic Yards

Head Length of Cres^(L) /n feef \

2' - O" 4'- 0" G'-O" S' -O"

4' -O" 3.5 4.2 4.9 5.G

5' -0" 3.7' 4.4 5.Z a. O

Pev/sed /0'/9-30

FORMLESS CHUTE

(CLASS "E" STRUCTURE)

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H.H.BENNETT, CHIEF

REGION- 3 R.H.MUSSER. DIRECTOR

Sheef/ofZ
ISOMETRIC VIEW

SHOWING COMPLETED FILL

ISOMETRIC VIEW

BAR TYPE DETAILS

Straight

TYPE-I

AXf

¿3^^

TYPE-2

Air

TYPE-3

TYPE-4

TYPE-5

QUANTITIES

3/8" STEELS FEET = POUNDS

VOLUME OF CONCRETE = CU.YDS.

t4^

HALF PLAN

LONGITUDINAL SECTION ON <L

STEEL SCHEDULE

MARK QUAN. SIZE LENGTH TYPE A B C TOTAL FT

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4. <t y-o' J 2'-J" o'-e" - tt- 0"

3 4 J'-S' J ?'-3" r-3" - 14-'-0'

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9 /o 4''0- 4 ^•-0- /•'O- - 40-0-

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/a & Ä-Ö- / - — 36''0'

ALL STEEL tf» /^V.c í/A/LESS Noreo

SCALE l/4"=l'-0"

FORMLESS CHUTE

(CLASS "E" STRUCTURE^

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT , CHIEF

IE6I0N= R.H.MUSSER. DIRECTOR

CARTOGRAPHIC APPROVAL: ^TCCHNIC/UyAPPROVAt.:

A.Mórafz

F.Henry

DATE

0-6-5/

DRAWING NO.

3-N-22845

She^^ZofZ
7-14

c. Types of Detailed Designs

Standard designs - These are designs prepared in advance to

fit various canbinations of conditions. An example of this

is the set of standard designs for reinforced concrete drop

spillways. Standard designs for this type and concrete

block drop spillways are designated by drawing numbers on '

Index Sheets, Figures 7.9 and 7.10, pages 7-15 and 7-I6.

Standard designs are also available for pipe drop inlets,

toe walls, and formless chutes.

After infonmation incidental to a structure design has been

secured by a field survey, it and all other pertinent information should be recorded on a structure data sheet. This

information is then used to develop the structure design.

All recorded information, calculations, and design data

should be checked for accuracy, and the data sheet approved

by a qualified individual before detailed design drawings for

the structure can be ordered from the regional cartographic

division. See Eegional Memorandum #60 and Cartographic Handbook for necessary procedure.

Special designs - These are prepared to fit each individual

case when standard designs are not applicable. They are

"tailor-made" designs, and are made only after properly prepared and approved data sheets have been submitted.

7.50 PEELIMINARY COST ESTIMATES

7.51 Useful Hints in Cost Estimating

a. Use standard index sheets to estimate quantities of material

in structures. These are given in Figures 7.8, 7.9, 7.10, and

7.11 (pages 7-12 and 7-13, 7-15, 7-l6, and 7-17).

b. Estimate the total costs of a structure on a "unit cost of

material in place" basis; i.e., cost per cubic yard of, reinforced

concrete or cubic yard of earth fill in place.

c. Become familiar with your local material, labor, and equipment costs and rates, or contact work group engineer.

d. It is better to over-estimate costs than to under-estimate.

Allow for waste or loss of material.

7.52 Example of Cost Estimating - In going over a farm with the

owner, a farm planner is asked to estimate the cost of a needed

structure at the lower end of a vegetated terrace outlet at a

point where the outlet enters an open ditch. The following is a

procedure:

Step 1 - Determine the extent and nature of the contributing

watershed, preferably with aid of aerial photo and casual inspection. The watershed is estimated at ko acres with normal runoff
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CONCRETE AND STEEL QUANTITES,

DRAWING NUMBERS, AND WEIR CAPACITIES

HEAD

WALL

HEIGHT

TOTAL

WEIR LENGTH OF WEIR OPENING "L" IN FEET

DEPTH

h + 6" 6-0" 8'-0" lO'-O" l2'-0" 14'-0" 16-0" 18'-0" 20'-0"

H h d

DRW6.N0. DRWG. NO. DRWG. NO. DRWG. NO. DRWG. NO. DRWG. NO. DRWG. NO. DRWG. NO.

CU.YDSi STEEL

CONCn LBS.

CU.YDS.|STEEL

CONG. 1 LBS. S"oí?^1=íll^ CU.YOS.|STEELCONC. 1 LBS. SSÎg^te CU.YDS.|STEELCONC. 1 LBS.

CU.yDS.IsTEEL

COHC. 1 LBS.

CU.YDS.|STEEL

CONC. 1 LBS.

Ï-O"

!"-6" 2'-0"

4110 4111 4112 41.3 41.4 41.5 41.6 4.17

7.0 i 400 7.7 i 445 83 i 499 8.9 ¡ 539 9.5 1 593 I0.2Í 65. .0.8Í 697 ..3 i 741

2*-0" 2'-6" 4130 4131 4132 4.33 4.34 4.35 4.36 4137

7.71 449 8.4| 492 9.11 552 9.7 i 594 I0.4| 652 .1.. { 712 1..8| 759 12.41 806

2-6" 3'-0" 4150 4151 4152 4153 4.54 4.55 4156 4157

e.5i 519 9.21 563 9.91 624 .0.5| 672 l..2| 727 II.9J 79. 12.6| 840 .331 885

3'-0" 3*-6" 4170 4J7I 4172 4173 4174 4175 4176 4177

9.41 615 .0.11 662 lOBJ 724 ...5 i 775 I23| 832 .3.0l 893 .3.71 946 14.41 987

4'-0"

r-6" 2'-0"

4210 4211 4212 4213 4214 4215 4216 4217

9.41 605 .0.31 670 ll.2| 746 .2.0| 808 12.9] 883 .3.81 965 14.61 1029 .53 1 1093

2'-0" 2'-6" 4230 4231 4232 4233 4234 4235 4236 4237

1031 665 11.21 731 12.. 1 811 I3.0| 876 13.91 954 14.8 1 1037 15.7 1 1106 16.61 'ITS

2'-6" 3-0" 4250 4251 4252 4253 4254 4255 4256 4¿7

ILOt 701 11.91 767 .2.81 849 13.7 1 9.. 14.61 993 .5.5 1 1075 .6.41 ..42 .7.3 1 1207

3*-0" 3-6" 4270 4271 4272 4273 4274 4275 4276 4277

Í2.6I 869 13.61 952 I43|.034 15.5 1 .103 I6.4| .2.1 .7.3! 1286 18.21 1361 19.2| 1435

5-0"

l'-6" 2-0" 4310 43.1 4312 4313 43.4 4315 4316 43.7

11.2 1 746 12.21 829 13.21 926 .4.2 1 1004 tS^I 1.05 16.21 .203 17.2 1 1286 18.21 1368

2'-0" 2-6" 4330 4331 4332 4333 4334 4335 4336 4337

12.01 911 13.01 .004 .4.0] .108 .5.0 1 1.97 .6.0} .337 .7.1 1 1418 18.1 LI52I 19.1 1 16.3

2'-6" 3-0" 4350 4351 4352 4353 43Î54 4355 4356 4357

13.5] 993 .4.6 1 1084 .5.6| 119. 16.7 1 1280 .7.71 .423 .8.81 ISI^ .9.8J .606 20.81 .728

3'-0" 3'-6" 4370 4371 4372 4373 4374 4375 4376 4377

15.41 1113 16.4] 1215 17.51 13.4 .8.6] 1407 I9.6| 1551 20.6| 1643 2..71 1763 22.81 .858

6-0"

l*-6" 2'-0"

4410 4411 4412 4413 4414 4415 4416 4417

14011045 15.2 1 1150 I6.3| 1267 17.5 1 1379 I8.6j^ 1513 19.7 1 .721 20.9| 1834 22.11 1969

2'-0" 2*-6"

4430 4431 4432 4433 4434 4435 4436 4437

15.3 1 1133 16.4 1 1238 17.61 1351 18.7 1 1521 19.9| 1676 2I.0| 1796 22ä| 2050 233 1 2.80

2-6" 3'-0'

4450 4451 4452 4453 4454 4455 4456 4457

16.01 1306 17.2 ] 1429 I8.3| 154. 195 1 1723 20.6| 1854 2I.8| 2.13 23.0| 2242 24.21 2439

3'-0" 3'-6" 4470 4471 4472 4473 4474 4475 4476 4477

17.71 1«0 18.8 1 1578 20.0| 1692 21.21 1881 22.4Í 202. 23.61 2287 24.81 2442 26.01 2583

7-0"

l'-6" 2'-0"

4510 4511 4512 4513 4514 4515 4516 4517

16.5 I 1410 17.6 1 1593 19.. 1 1715 20.41 1856 21.61 2018 ZZ.S\ 2.71 24^1 2328 253 12462

2'-0" 2'-6" 4530 4531 4532 4533 4534 4535 4536 4537

.7.2 1 I83j 1647 I9ä| 1770 2... 1 1919 22.41 2026 23.7 1 2226 26.0| 2406 27.4 12512

2"-6" 3'-0" 4550 4551 4552 4553 4554 4555 4556 4557

.9.11 20.41 .894 21.71 2009 23.0| 2172 243j 2330 26.81 2762 295| 2789 B 3..01 2802

3'-0" 3*-6" 4570 4571 4572 4573 4574 4575 4576 4577

2051 2.-8 1 .908 23.112095 24.41 2205 26^1 2389 28a 1 2564 » 30.7| 2875 "32^12934

8-0"

l'-6" 2'-0" 4610 4611 4612 4613 4614 4615 4616 4617

20B1 2^2| 23.6| 1996 25.1 |2I34 263|2352 29.41 2503 " 30.9| 3032 » 32.31 3028

2'-0" 2"-6" 4630 4631 4632 4633 4634 4635 4636 4637

22.01 23.51 2431 20.2 263 1 2125 27.7] 2250 • 30.71 •3221 » 33.71

2'-6" 3'-0" 4650 4651 4652 4653 4654 4655 4656 4657

2421 25.61 27.01 2144 2a4|2266 »3.^1 32.7 1 2796 "34.2| 35.61

3'-0" 3-6" 4670 4671 4672 4673 4674 4675 4676 4677

25ÄI 27.21 2&6| 2556 30.0| 2759 • 32B12740 "343 [3015 > 35B|323. » 37.3 1 3427

9'-0"

l'-6" 2-0"

4710 4711 4712 4713 4714 4716 4617

1 1 1 1 1 i

2'-0" 2'-6" 4730 4731 4732 4733 4734 4736 4737

1 i 1 1 1 1 1 1

2'-6" 5-0" 4750 4751 4752 4753 4754 4755 4756 4757

1 1 1 1 1 1 i 1

3'-0" 3'-6" 4770 4771 4772 4773 4774 4775 4776 4777

1 36.01 2874 1 39.4| 3132 1 44.51 3512 i 1

10-0"

l'-6- 2'-0"

48.0 4811 4812 4813 4814 4815 4816 4817

i 1 1 i 1 i 1 1

2-0" 2'-6"

4830 4Ó3I 4632 4833 4834 4835 4836 4837

i 1 40ä| 3313 1 1 1 1 1

2'-6" 3-0"

4850 4851 4é52 4853 4854 4855 4856 4857

i 4..0| 3339 i " 46.7| 3797 1 " 50.514152 1

3*-0" 3f-6"

4871 4872 4873 4874 4875 4876 4877

1 1 1 1 1 1 1 i

-A -^

HEADWALL EXTENSION

2.25 h

[

1/2 ELEVATION SECTION A-A

CHART SHOWING CAPACITY OF WEIRS

HEAD

LENGTH OF WEIR OPENING V IN FEET

6'-0' tf-or lO'-OT l2'-0il4'-0" i€-(f .rf-oW

r-6" 34.9 47.1 59.3 7L6 83.8 96.1 .08 .2.

2'-0" 52.8 7..6 90.4 109 .28 .47 .66 185

2'-6" 72.4 98.7 125 .5. .78 204 230 257

3'-0" 93.4 .28 162 197 232 266 301 336

3'-6" .16 159 203 246 290 333 377 421

CAPACITY OF WEIRS

Q - 3.33{L-0.2h) h^

with buttretscB

DESIGN DATA

f,» lepOO.fè* 2p00,fe-800,v«40,u«l00

Stress«« in pound« p«r squor« inch.

Trapezoidal loading on headwall «60lbs.per square foot,

on sidewolls 40 lbs- per square foot.

Steel cover « 2", except on earth 3'.

Where possible,all steel shall be secured In place before

concrete is poured.

Only material conforming to A.S.T.M. shall be u«ed.

Steel to be intermediate grade new billet deformed bors.

Fillets may be used on inside corners If desired.

Curved lip and entrance ore optional.

Construction joints,when necessory, to be formed by using

beveled 2"x 4".

Steel weights do not oilow for waste due to cut-ting.

If footings ore required, add 10% to steel weights and 15%

to volume of concrete.

NOTE : "STRUCTURE DATA SHEET MUST ACCOMPANY

REQUEST FOR DETAIL PLANS."

Revised 3-11-46

PERSPECTIVE VIEW

REINFORCED CONCRETE

NOTCH SPILLWAY DAMS

RELATIVE DIMENSIONS. CONCRETE AND STEEL

QUANTITIES. DRAWING NUMBERS.WEIR CAPACITIES

REGIONAL OFFICE

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H.H. BENNETT. CHIEF

CARTOGRAPHIC APPROVAL:

DESIGN DRAWN

6.W.F0STER C.L.YULE

TECHN.CAL APPROVAL:

CHECKED DATE DRW6. NO.

6.W.F0STER 10-17-1940 5-N-4I00

I

\J1
^-16

DRAWING NUMBERS AND MATERIAL QUANTITIES

Height of

Overfall

Depth

of Weir

LENGTH OF W EIR OPENING ^ 1

4'-0 8-0" l¿-0" l6'-0" 2Ö-0"

H d

DRAWING NO. DRAWING NO. DRAWING NO. DRAWING ^0. ßRAWiNG NO.

CONC.

CU. YDS.

STEEL [BLOCKS

LBS. 1 NO.

CONC. 1 STEEL 1 BLOCKS

CU.YDS.I LBS. 1 NO.

CONC. 1 STEEL 1 BLOCKS

1 NO.

CONC. STEEL BLOCKS

CU. YDS. LBS. NO.

CONC.

CU. YD& ^III'- BLOCKS!NO. 1

r-8"

i'-4" 15202 15204 15206 15208 15210

2.7 17.4 1 88 3.8 1 33.4 1 97 4.8 1 54.8 1 106 57 1 70.78 1 115 6.7 1 90.21 1 124

2f-0" 15222 15224 15226 15228 15230

3.2 17.0 116 4.3 1 38.5 1 125 5.4 1 60.0 I 134 &4 1 82 1 143 7.5 1 104 1 152

2f-8" 15242 15244 15246 15248 15250

1 1 1 - 1 1 ■■ 1

3'-4" 15262 15264 15266 15268 15270

1 1 1 1

4'-0" 15282 15284 15286 15288 15290

1 1 1 1

2*-4"

l'-4". 15302 15304 15306 15308 15310

3.3 1 14 123 4.4 1 34 1 135 5.4 1 50 1 147 6.3 1 68 1 159 7.6 1 85.5 1 171

2'-c/;. 15322 15324 15326 15328 15330

4.6 1 329 1 162 6.0 1 384 1 174 7.3 1 447 1 186 8.7 1 510 1 198 10. 1 1 573 1 210

• 2'-8" 15342 . , 15344 15346 15348 15350

5.2 L 359 1 212 7.6 1 421 1 224 8.0 1 480 1 236i 9.3 1 540 1 248 10.7 1 599 \ 260

3'-4" 15362 15364 15366 15368 15370

1 1 1 1

4'-0" 15382 15384 15386 15388 15300

6.7 1 606 315 8.2 1 684 1 327 9.7 1 746 1 339 10.2^ 1 808 1 351 12.7 1 870 1 363

3'-0"

l'-4" 15402 15404 15406 15408 15410

4.6 1 310 160 6.0 1 376 1 175 7.3 1 440 1190 8.6 1 505 1 205 10.0 1 570 1 220

2'-0" 15422 15424 15426 15428 . 15430

5.3 1 316 215 6.7 1 451 1 230 8.1 1 514 1 245 9.3 1 577 1 260 10.6 1 640 1 275

2'-8" 15442 15444 15446 15448 15450

5.7 1 551 1 248 7i2 1 649 1 263 8,7 1 732 1 278 10.3 1 816 1 293 11.7 1 899 1 308

3'-4" 15462 15464 15466 15468 15470

6.9 1 722 1 335 8.3 1 852 1 350 lO.I 1 947 1 365 11.7 1 1042 1 380 13 3 1 1137 1 395

4'-0" 15482 15484 15486 15488

1 1

Ï-8"

r-4" 15502 15504 15506 15508 15510

5.4 1 372 1 208 6.7 1 439 1 226 8.0 1 508 1 244 9.7 1 576. 1 262 II. 1 1 644.2 1 280

2'-Ö' 15522 15524 15526 15528 15530

6.0 1 445 1 260 7.5 1 513 1 278 &.0 1 581 1 296 10.5 1 650 1 314 12.1 1 717 1 332

2'-8" 15542 15544 15546 15548 15550

6.9 719 1 326 8.3 1 834 1 344 lO.I 1 930 1 362 II ,7 1 1041 1 380 133 ,1 1123 1 398

3'-4" 15562 15564 15566 15568

7.4 1 772 364 9.1 1 893 1 382 9.9 1 995 1 400 12.6 1 1096 1 418

4'-0" 15582- 15584 15586

7.7 i 889 1 418 9.5 1 1005 1 436 11.2 1 1106.3 1 454

4'-4"

l'-4" 15602 15604 15606 15608 15610

5.4 1 500 [ 257 7.1 1 616 1 278 8.8 1 711 1 299 10.6 1 807 1 320 12.3 1 902 1 341

2'-0" 15622 15624 15626 15628 15630

6.5 1 684 315 8.1 1 80a 1 336 9.8 1 904 1 357 M.5 1 1005 1 378 \Z.\ 1 It07 1 399

2'-8" 15642 15644 15646 15648

7.5 1 807 1 381 9.2 1 922 1 402 11.0 1 1026 1 423 12.7 1 1130 1 444

3'-4" 15662 15664 15666

7.8 1 1288 1 417 9.5 1 1476 1 438 11.4 1 .1640 1 459

4'-0" 15682 15684

1 1

5'-0"

l'-4" 15702 15704 15706 15708 15710

6. 2 1 663 1 298 8.0 1 788 1 322 9.8 1 896 1 346 11.6 1 1004 1 370 13.4 1 1112 1 394

2'-0" 15722 15724 15726 15728 15730

76 1 826 1 393 9.3 1 956 1 417 II. 1 1 1060 1 441 12.8 1 1168 1 465 14.6 II283 1 489

2'-8" 15742 15744 15746

7.7 1 1389 1 424 9.,4 1 1593 1 448 11.2 1 1760 1 472

3-4" -15762 15764

1 1

4'-0" 15782

1 i

of this spillway is limited to grade stabilization

i protection of the outlet of sod flumes orchonded as a water impounding structure,

¡opacities given do not include freeboard within

fill berms shall be constructed to a minimum

-O" above the top of the heodwall extensions,

ways allow 0'-6" (minimum) freeboard.

DISCHARGE CAPACITY OF SPI LLWAY IN C.FS.

NOTE:

The general use

and as toe walls for thi

neis. It is not recommen

The discharge c

the spillway. The earth

settled fill height of l'

On special design spill

HEAD

"h"

LENGTH OF WEIR OPENING "L" IN FEET

4 8 12 16 20

l'-4" 19 39 60 80 100

2'-0" . 34 71 • 109 • 147

2'- 8" 50 103 166 225 283

3'-4" 68 148 230 311 391

4'-0" 86 193 299 406 5^5

Q=3.33(L-a2h) h'/2

'^-,^^^^^^^^<^^1

^ . -^

Re>/ised 1-13-53

^^^^^m¡

TS

DR

INDEX SHEET FOR

Ï CONCRETE BLOCK STRAIGHT DROP SPILLWAY

^R^^Wv^^^^^^^^^

1

X

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE U ; UPPER MISSISSIPPI REGION

ELEVATION REFERENCE:

NOTE:

"STRUCTURE DATA SHEE

CARTOGRAPHIC APPROVAL TECHNICAL, APPROVAL 1

<*,.^^%r •* *.=*-^^^^^??t^ III' „,

1—

MUSI

DET/S

r AGGO

IL PL

MP/

ANS

\NY REQUE ST F DESIGNED DRAWN

A.F.M0RAT2 C.YURK

CHECKED

A.F.MORATZ

DATE

11-8-82 3-L-22853

SHEET OF

FIGURE 7.10 CONCRETE BLOCK STRAIGHT DROP SPILLWAY
CONCRETE QUANTITIES IN CUBIC YARDS

HEAD

WALL

HEIGHT

H

3-0"

TOTAL

WEIR

DEPTH

d

TW

1^

3Ï? ~^

I'-O"

T^

4-0"

^-0"

6^0"

r-0"

tf-O"

s/-or

lO'-Of

4^

2^:6"

LENGTH OF WEiR OPENING "L" iN FEET

4Î^

3!:^

2-6"

3^-6"

2-0"

3?-Ç

8-0" 10-0" 12-0" 14-0" 16-0" 18-0" 20-0"

2i.8

3;-o"

3-6"

2-0"

4-0'

7:^"

2-oí'

¿-6"

3?-0f'

4!-or

80.5

91.5

32.1

33.0

2g.9

13.8

33.0

"me

79.7

89.0

ADDITIONAL

VOLUME IN

CUBIC FEET

FOR EACH

.ADDITIONAL

FOOT IN

WEIR

LENGTH

12.8

"TTTT

57.3

57.6

r*A

l'-QÜ

l,5(H-0.5d) + 4-0" But not

less than H+d+3'-ö"

HEADWALL

TOEWALL

HEADWALL t^XTENSION

,^i-5T

vWINGWALL

_i

From^l

Curve "C"

l.5(H + d) +2H

2

i-^A

HALF ELEVATION

DATA

All walls designed as true gravity section,

independent of one another.

Tropezodial loading on heodwall = 62.5 lbs.

per square foot, on sidewalls and wingwalls

= 30 lbs. per square foot, on heodwall extensions = 15 lbs. per square foot.

Construction joints, when necessary, to be

formed with beveled 2" x 4".

Concrete quantities computed on structure as

shown; no allowance made for waste or overrun.

Place two 2" round weep holes in each sidewall 3" above apron. Ploce gravel drain around

eoch weep hole on eorth fill side of wall.

See table below for apron thickness.

HALF PLAN

n 4'.o" 6'-0"

7-0"

8'-0"

9'-0"

10-0"

APRON f..Q"

THICKNESS ''"'' 0-IÖ' 0-11" r-0" 2 3 4 5 6

TOTAL WIDTH OF BASE-FEET

1 TABLE SHOWING CAPACITY OF WEIRS

d

LENGTH OF WEIR OPENING "U" IN FEET

6'-0" a'-o" 10-0" 12-0" l4'-0" l6'-0" 18-0" 20'-0"

I'-O" 17.4 23.4 29.4 35.4 41.4 47.4 53.4 59.4

l'-6" 31.4 42.4 53.5 645 75.5 86.5 975 109.

2-0" 47.5 64.5 814 98.4 115. 132. 149. 166

2-6" 65.2 88.9 113. 136 160. 184. 208. 231.

3-0" 84.2 115. 147. 178 209. 240. 271. 302.

3'-6" 104. 143. 183. 222. 261. 301. 340. 379.

4^0" 1 125. 173, 221. 269. 317. 365. 413. 461.

i CAPACITY OF WEIRS ="Q"= 3.0 {L-0.2d)dH = C.FS.

PLAIN CONCRETE

NOTCH SPILLWAY DAMS

RELATIVE DIMENSIONS, CONCRETE QUANTITIES,

BASE WIDTH OF WALLS. WEIR CAPACITIES.

REGION NO. 3 REGIONAL OFFICE

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H.H.BENNETT. CHIEF

CARTOGRAPHIC APPROVAL: TECHNICAL APPROVAL:

I

DRAWING NO.

3-N-7236
7-18

characteristics and rainfall factor of 1.0.

Step 2 - For estimating purposes, calculate the runoff from the

watershed on a 50-year frequency basis for all structures. Eefer

to Part 3.10, page 3-1. The runoff is estimated at 100 c.f.s.

Step 3 - Estimate head to be controlled (overfall into ditch) by

use of hand level. Head to be controlled is determined as five

feet.

Step k - Decide on type of structure to be used as influenced by

site characteristics. Reinforced concrete drop spillway is

selected.

Step 5 - By referring to Figure 7.9 select dimensions of weir

notch to provide proper capacity.

h = 2'6" L = 8'

Also determine drawing number and quantity of material from

table.

For (h = 2^6" H = 5*

(d = 3' L = 8»

(Use Drawing No. 4351

{Ik.6 cubic yards of reinforced concrete

required

Step 6 - Estimate cost on "material in place" basis.

15 cubic yards at $40.00 per cubic yard in

place (contractor's price) $600

400 cubic yards of earth wing levees at

$0.20 per cubic yard 80

Add 10 percent for contingencies 70

Estimated net cost $750

Note: This figure is only a preliminary estimate. See Part 7,

Paragraph 7.43c for procedure in seciiring detailed plans.

Similar cost estimates should be made for other adaptable structures for the site in question. Comparative costs should be

considered in making a final selection.
7-19

7,60 HOW TO PECMOTE GOOD QUALITY IN CONSTRUCTION

7.61 Lay the "groimdwork" with the farmer by:

a. Emphasizing the need for using construction material of

acceptable quality.

b. Emphasizing the importance of building the structure as

planned and designed. Regional Memorandum #60 requires withdrawal of Service assistance whenever the cooperator refuses to

follow approved plans.

7.62 Give timely, adequate technical assistance both before and during the actual construction by:

a. Providing sufficient stakes for construction purposes.

"Double-check" your staking.

b. Explaining the stakes to the farmer or the contractor, making

sure he understands.

c. Explaining the construction details to the farmer or contractor.

d. Providing timely supervision and checking during the construction period.

7.63 Acquaint yourself with competent, reliable contractors in yoiir

locality. The farmer will appreciate a list of reliable contractors, should he not be able to do the work himself.

7.70 STRUCTURE MAINTENANCE

7.71 Important - Regardless of how well designed or constructed a

permanent structure may be, its continued effective operation

depends on how well it is maintained. Emphasize to the farmer

the need for a sound maintenance program.

7.72 Essentials of Sound Maintenance Program

a. The farmer should inspect 'the structure regularly for:

1. Debris or obstructions at inlets or outlets of structures.

2. Destructive action of burrowing rodents under structure

proper or through adjacent earth fills.

b. The farmer should make necessary repairs or remove debris

immediately after inspection.

c. Protect structures from livestock.

d. Maintain all earth fills in good sod by mowing, re-seeding,

and fertilizing.
'7-20

DRAWING NUMBERS AND MATERIAL QUANTITIES

HEIGHT OF

HEADWALL

DEPTH

OF WEIR

LENGTH OF W EIR OPENING

6-0" 8"^Ö" lO'-O" IZ-O" l4'-0" le'-o" IS'-O" 20'-0"

DRAWING NO. DRAWING NO. DRAWING NO. DRAWING NO. DRAWING NO. DRAWING NO. DRAWING NO. DRAWING NO.

CONG. STEEL

OU. YDS. LBS.

CONG. STEEL

CU. YDS. LBS.

CONG. STEEL

CU. YDS. LBS.

CONG. STEEL

CU. YDS. LBS.

CONG. STEEL

CU. YDS. LBS.

CONC. STEEL

CU. YDS. LBS.

GONG. STEEL

CU. YDS. LBS.

CONG. STEEL

CU. YDS. LBS.

I'-O"

I'-O"

2.6 1112^

7410

-6" 7428

2.9 I Í30."0"

7414

3.2 1137.0 3.5 1150.0 3.8 1 163.0 4.4 189.0

2.6 I 109.5 3.0 I 123.8"

7430 7434

3.4 I 138.1 3.8 1152.4 4.2 I 166.7

7436

4.6 I lei.ö" "5:0

7438

19572 5.4 1209.5

-0" 7448 7452

2.0 1156.0 2.3 I 173.0 2.5 1190.0 2.7 1207.0

7456

0 1224.0 3.2

-6" 7472

7458

1241.0

7460

3.4 1258.0

4.0 I 180.0 4.4 I 196.0 4.8 1212.0 5.2 12280 5.6 I 244.0 6.0 1260^

7478

6.4 1276.0"

0" 4.5 1291.0 4.9 1308.8 5.3 1326.8 6.1 1362.9 6.5 1380.4

7498

6.8 T292.0

6.9 1398.8

0" 7606

2.9 I I29.Ö 3.3 I 147.0 3.7 I I64.Ö'

-6"

I'-6"

3.3 I 16570 3.7 I 164.-Ö

7630

7614

5 1200.0 4.9 1217.0 5.3 [231.0 5.7 252.0

4.1 I203.Ö 4.5 I222.Ö

3.7 I I47.Ö" 4.1 1160.0

7650

5.0 1240.0" 5.4 (260.0 5.8 I278.Ö 6.2 1297.0

4.6 I I73.Ö 4.9 I 185.0 5.3 1198.0"

7658

5.7 I 211.0 6.1 1223:0 6.5 1236.0

-6" 7666

4.8 1370.0

7670

5.3 I 40I.Ö 5.8 143370"

7672

6.3 [465:0^

~0" 5.2 I 390.Ö 5.7 1414.0 6.2 144870

7692

6.8 1497.0

7678

7.8 156170

7680

7694

6.7 1468.6 7.2 1495.9"

7698

8.3 I 593.Ö

8.2 1551.2 8.7 1577.8

0" 7814

3.8 I 314.0 4.3 1349.0 4.8 1384.0 5.3 1429.0 5.8 I454.Ö"

7820

6.3 489.0 6.8 1524.0 7.3 I559.Ö

-6" 4.0 1313.0 4.5 I 348TÖ 5.0 1383.0

2'-0"

5.5 [419.^

7834

6.0 I454.Ö

7846

4.2 I 336.Ö" 4.7 J 372.0 5.2 1407.0

-6" 7866

5.7 144370

7854

7836

6.5 I489.Ö

7840

7.0 524.0

6.2 1478.0

7856

7.5 I 559.0^

6.7 I5I5.Ö

5.6 1474.0"

7886

6.1 I 51170

7872

6.6 1549.0

6.1 15497Ö

7888

7.1 I 586."Ö'

7876

7.2 I550TÔ"

7860

7.7 1586.0

7.6 623.0 8.1 I660.Ö

-0" 7906

6.6 158670 7.1 1623.7

7892 7896

4.3 T343"7Ö

7908

7.6 I 66I.Ô 8.1 1699.0 8.6 I736.Ö

8.6 I697.Ö

7898

7880

9.1 [734.0

4.8 1380.0 5.3 1417.0

7912 7916

9.1 I773.Ö

7900

5.8 I 454.0 6.3 1491.0 6.8 1528.0

7918

7 3 I 56S.Ö

9.6 I enTo

7920

7.8 I 602.0

-6" 7928

2'-6"

4.6 r362.0

-0" 7946

5.1 [399.Ö 5.6 I 435.0 6.1 [473.0 6.6 1510.0 7.1 [ 546.0 76 I 584.0

5.0 1384.0

7966

5.6 142170^

7950

6.1 I4597Ö

5.9 I459.Ö

7970

6.7 I496.Ö 7.8 I572.Ö 8.4 I609.Ö 9.0 I 647.0

6.5 T494.3

0" 6.3 I535TÖ"

7988

6.9 1532.4

7972

7.5 [569.1 8.1 1605.9

6.9 I 574.Ö

7990

7.5 I 6I6.Ö 7992

8.1 I6627Ö

7994

8.7 j 64276 9.3 1679.4

8.7 17030

7996

9.3 I744.Ö

7998

9.9 [7I6.T

DISCHARGE CAPACITY OF SPILLWAY IN CF.S

9.9 [786.Ö mD.5 [

QQ-.

HEAD OVER

CREST

I'-O"

r-6"

2'-0-

2'-6"

3'-0"

LENGTH OF WEIR OPENING "L" IN FEET

6' - 0" 8'-0" 10'-0" 12'-0" 14'-0'

232

16'-0" 18'-0" 20'-0'

21 23

66

121

185

257

336

NOTE =The spillway discharge capacities are computed from the formula Q = 3.33 (L-0.2h) h ^2

When the crest is submerged by high tailwater

ir^ the downstream channel,the formula Q = 3.33

(L-0.2h)(Nh)V2 should be used to determine spillway capacities. The value of the coefficient "N" is

given in the table on drawing No. 5-L-7285.

Where weirs of greater length than 20*-o"

are reguired the apron ond heodwoll can be expanded using the same detailing and cross-section di-

'mensions.For expanded headwalls,buttresses ^(counterforts) should be added at approximately 12-0

on centers.

This spillway should be used primarily as a

toe-wall for sod flumes and at critical sections in

constructed waterways.

L

XT

x:

TÎV

1

X

1 il1

11

1

ELEVATION

INDEX SHEET FOR

R/C STRAIGHT DROP SPILLWAY

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

1. BENNETT, CHIEF

R.H.MUSSER,DIRECTOR

CA5ITO6RAPHIC APPROVAL

DESIGNED DRAWN

A.FIMORATZ C.YURK

CHECKED

R.MICHAUD

^ TECHNIi

FIGURE 7.12 INDEX SHEET FOR R/C STRAIGHT DROP SPILLWAY
8-1

PART 8

TERRACING

8.10 GENERAL

8.11 Definition

A terrace is a constructed channel across a field slope "built to

standard specifications. It may be constructed either with a

grade or with the channel and ridge of the terrace being level.

a. A graded terrace is one constructed so that it will have a

grade^ either variable or uniform^ leading to a suitable outlet^

designed for a safe and non-erosive velocity.

b. A level terrace is one constructed on a true contour where

the channel becomes the impounding reservoir. The water is permitted to seep into the soil.

8.12 Uses and Limitations

a. Advantages of Terraces

Reduces length of slope

Reduces soil losses

Permits the use of more intensive rotations

Provides larger fields not broken by strips which can be

more readily pastured as a unit.

Terraces, when properly used and constructed, are the most

effective supporting conservation practice.

b. Limitation of Terraces^

They will not replace the need for good rotations in maintaining soil structure and fertility.

They will not replace the need for contouring.

Generally, terraces are not recommended on cropland slopes

steeper than 10 percent.

c. Level Terraces

Level terraces should not be used except where all of the following conditions exist:

*Reference

Technical Operations Plan or State Bulletin.
8-2

Light textured or medium textured soils of high organic content where a good soil management system is followed so that

the surface soil will not seal.

Where there is at least five feet of moderately or moderately

rapid, permeable soil with less than 35 percent clay content.

d. Graded Terraces

Graded terraces should never be used unless there is a suitable outlet such as:

A natural outlet consisting of a waterway or a slope

having sufficient cover and adequate width to prevent

erosion.

A constructed and vegetated outlet along a fence or at

some other suitable location.

8.20 PLANNING THE TEREACE SYSTEM

8.21 Preliminary Field Surveys

The farm planner should make sufficient surveys which will

enable him to properly plan the terrace system. Sometimes

merely a contour line will be sufficient. In more complex layouts it may be necessary to have a complete topographic survey

made or to make a preliminary layout of the system in the field.

8.22 Correlate the Terrace System With the Farm Plan

A terrace system properly planned and integrated with the general farm plan becomes a very valuable improvement. However, a

system poorly planned and poorly laid out can, and generally

does, become a source of difficulty in operating the farm.

8.23 Roads and Lanes

Plan the location of roads and lanes carefully. The system can

often be so planned that the roads may be placed on the field

ridges providing easy access to the area between each terrace.

The road may also be placed on or just below a terrace ridge.

This permits easy travel and will prevent erosion of the traveled

way. The ease with which crops can be removed from terraced

fields is important.

8.2ÍI- Outlets

Refer to Part 10 on Vegetated Outlets and Watercourses.

8.25 Terrace Specifications (Figure 8.1, page 8-3)

The terrace should be constructed according to specification

regardless what type of equipment is being used. Copies of
TERRACE CHART 8-3

1 Channel

Cross Section

GRADED TERRACE CHANNEL DIMENSIONS

^^^

Needed Terrace Ridge

Height in Feet

Ap

Slo

proximate

)e Ratio

^'^^ 200 400 600 800 1000 CBS RFS RBS

1 0.8 0.9 1.0 1.2 1.2 10 10 10'. 1

2 0.8 0.9 1.0 1.2 1.2 10 10 10-. 1

3 0.7 0.9 1.0 I.I 1.2 6 8 8:|

4 0.7 0.9 1.0 I.I i.l 6 8 S'\

5 O.Z 0.9 1.0 I.I i.l 6 8 8M

6 0.7 0.8 0.9 1.0 1.0 6 8 8:|

7 0.7 0.8 0.9 1.0 1.0 4 6 6:1

8 0.7 0.8 0.9 1.0 1.0 4 6 6:l

9 0.7 0.8 0.9 1.0 1.0 4 6 6*-l

10 0.6 0.8 0.9 1.0 1.0 4 6 6:1

II 0.6 0.8 0.9 1.0 1.0 4 4 5'\

12 0.6 0.8 0.9 1.0 1.0 4 4 4:1

13 0.6 0.8 0.9 l.O 1.0 4 4 4-1

14 0.6 0.8 0.9 1.0 1.0 4 4: 3M

15 0.6 0.7 0.9 1.0 1.0 4 4: 2Îfe:|

NOTE- Above figures are settled ridge height and ore based

on lOyr. runoff and a channel with 6' bottonrt, 0.4 percent

grade. The same height should be used for 0.6 percent grade

The height should be increased O.l'for a grade of 0.2 percent.

A top width of at least 2' should be provided.

TERRACE VELOCITY CHECK CHART

Depth of water ¡n feet required for various amounts

of runoff and related grades in channel

Terrace channel grade ( per cent )

0.2 0.4 0.6 0.8 1.0 1.5 2.0

Depth of water ( feet )

Runoff c.f.s.

2

3

5

10

0.4 0.3

0.5 0.4

0.6 0.5

10.9 0.8

I ft/sec -

0.3

0.4

0.5

0,7

0.3

0.3

0.5

0.6

0.2

0.3

0.4

I 0.6

0.2

0.3

0.1

0.2

I 0.4

0.6

0.4

0.5

Velocity 2 ft/sec.

The figures to the left of the first stepped line represent

velocities of less than one foot/second. Those between the

lines represent velocities of one to two feet/second and

those to the right represent velocities over two feet/second.

NOTE: For short distances terrace grades can be increased

to improve allignment. The above velocity chart permits a

check of channel velocity Safe velocities for bare soils are:

Sandy Soils 1.5'per second. Other Soils 2.0'per second.

Chart is based on 6' bottom, 4 to I side slopes and a roughness coefficient "n"of 0.04. Runoff can be figured by multiplying area drained in acres by 4 c.t s.

LEVEL TERRACE- CHANNEL CAPACITY-BASED ON RETAINING 2 " RUNOFF

f=;ield

Slope

Distance ( feet )

From A to : Depth (feet) Cross- Section

End Area sq.ft.

Approximat«

Slope Rati 0

Width (feet)

% B D E »tsd Cut c Excav. Fill CBS . Ri^s RBS Channel R!4g.e .

2 7.0 17.5 24 1.2 0.6 5.0 5.4 6-.| 6 6-1 8 3

4 8.2 20.0 28 1.2 0.8 7.4 7.4 5M 6 6M 8 3

6 9.5 21 30 1.3 0.8 8.7 9.4 5:1 6 5:1 8 3

8 II.0 21.5 32 1.2 0.9 9.2 8.9 5:1 6 5:1 6 3

10 13 22 32 1.2 1.0 10.1 9.9 5-1 5 4:1 6 3

12 12 20 1 31 1.3 I.l 10.9 10.2 4:1 4 ' 4:1 6 3

^ 14 13 21 30 1.3 0.9 10.2 11.0 4:1 4 3^:1 6 3

¥r 15 12 20 28 1.3 1.0 10.8 10.6 3iM _ji 2i:| 6 3

SPACING FORMULA ii" + 2 )

Field Slope % 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15

Vertical Interval 2.5 3,0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7,5 8.0 8.5 9.0 9.5

Horizontal Interval 250 150 117 1 00 90 83 79 75 72 70 68 67 66 64 63

Feet per Acre 174 291 373 436 485 525 552 581 605 623 642 650 660 682 692

Acre per 1000 ft. 5.74 3.45 2.68 2.30 2.06 1.91 1.82 1.72 1.65 1.61 1.56 1.54 1.52 1.47 1.45

-LEGENDCBS-Channel back slope

RFS-Ridge fore slope

RBS-Ridge back slope

S - Slope of land

-GENERAL RECOMMENDATIONS.

1. Provide uniform grades ranging from .3' to -6' per 100 feet of terrace length.

2. Grades can be varied to provide alignment of terraces as nearly

parallel as topography will permit.

3. Convey runoff at non-erosive velocities.

4. Leave no depressions in channel over 0.2'deep.

5. Usually the top terrace should be located one interval below top of slope.

6. Terraces must discharge into natural or constructed vegetative areas or outlets where

cross section assures safe velocities.

7 All planting and tillage operations shall be done parallel to the terraces.

8. Spocings may be increased or decreased 10% to suit local conditions.

9. No secondary channel shall be left below the terrace ridge.

NOTE : For more detailed information use local technical guide or consult qualified technicians.

MAY- 1952. FIGURE 8.1 STANDARD TERRACE Revised 4-6-53 3-L-28373
8-V

Figure 8.1 can be secured from the Regional Supply Center. Order

by Drawing No. 3-L-26266.

a. Spacing

In very tight soils where high runoff may cause rilling and erosion between the terraces, the spacing should be somewhat less

than shown in the table. However, in porous soils high in organic matter the spacing may be increased. Consult local technical

operation plan for local deviations from the standard specifications.

b. Grade

Either variable or uniform grades may be used. The use of a variable grade often permits better alignment of the terrace and to

better fit the terrace to the field. In some localities with

uniform field slopes, terraces may be staked parallel. This will

require some adjustment of the grades. It may also require some

cutting and filling.

When terraces are used for drainage purposes on wet land or passing through seep areas, the terrace grade may be increased

materially (25-5O percent).

If erosion should develop at end of terrace, keep that portion m

sod.

c. Length

The maximum length will generally be about I6OO feet. If longer

terrace is desired, check the rimoff and design, using diversion

design chart for the necessary capacity to handle the extra runoff at non-erosive velocities.

8.26 Location of Top Terrace

The location of the top terrace is very important. If the top

terrace fails, it often causes the failure of the lower terraces.

Before locating the top terrace, inexperienced personnel should

consult someone who has considerable experience in terrace layout.

Some general rules for location of the top terrace are:

If the top of the hill comes to a point, the interval may be

increased to one and one-half times the regular terrace interval.

On long ridges, where the terrace approximately parallels the

ridge, the regular interval should be used.

The watershed area above the top terrace should not exceed

four acres.
8-5

8.30 STAKING TERRACES

8.31 Starting Point

a. After the vertical interval has been determined for graded

terraces^ staking of the terrace line may begin either at the

outlet or some other point in the field. The first stake 50

feet from the outlet should be set .3 foot to .5 foot plus the

cut "c" shown in the table above the terrace outlet. (See

Figure 8.1.) This is to allow for the channel cut made in construction and the possible silting in the terrace outlet.

b. Rod readings by stations and suitable notes should be kept

to facilitate layout^ construction, and checking.

8.32 Location of the Stake Line in Relation to Completed Terrace

The channel of thexcompleted terrace should coincide with the

stake line. Offset lines ïor starting terrace construction may

be made as indicated on Figures 8.2, page 8-6; 8.3, page 8-7;

and 8.if, page 8-8 so that this will be achieved. (The ridge of

level terraces should coincide with the stake line.)

8.33 Adjustment to Improve Sharp Bends

After the line has been staked it is well to check and arbitrarily move some stakes if necessary to ease sharp turns.

Ordinarily, limit such adjustments so that not more than six

inches of extra cut or fill will be made. With a little experience, stakes can be moved up or down the slope to compensate for

the equipment "creeping" while going aroiind sharp bends.

8.40 CONSTRUCTION OF TERRACES

d.kl Methods

a. Preparation of Field

All dead furrows or ditches to be crossed should be filled in

before the construction begins to prevent seepage through

terrace ridge and to facilitate construction.

All old fencerows should be leveled off.

Surplus vegetation should be removed if the terrace is to be

constructed with a plow or a whirlwind terracer.

Heavy sod should be thoroughly disked.

b. Moldboard Plow - From Both Sides

In starting the construction, the operator either leaves an

island or he may start by backfurrowing. This is a matter for

259293 0-53-9
8-6

Mefhodaffer 5eWn¿ channe/stakes. Plow first furrow Sft down hi/t from channel stakes

and return furrow 15ft down hill from channelstake as indica fed. Locate Ist furrow and return

furrow bystakin¿i or, by two men with a rodheld belween them. One ofthese men walks the

channel stakes, the other walks aheadof theplow. When We first five rounds are completed, start

successive plowings by numbered rounds. Note irregularity in return trip ofround 11.

This drawingis based on use of a two-boftomj4,or 16- inchplow. Removejointers.

Coulter may be lefton. Use sharp shares. Maintain enough speed to turn furrowslice completely

over Remove crop residues and disk heavy sodwe//¿>efore plowing.

Ifterrace ridge is not /Ae desired hetght', additionalplowing may be necessary.

To increase the size and width, additional rounds per plonking may be necessary.

FIGURE 82 A METHOD FOR TERRACE CONSTRUCTION PLOWING FROM BOTH SIDES
8-7

-^1.1 ^ 0^-^:irz.

"^ ^?iî^ #^-.*^^ k¿'' •# I % -^ "-^^ \ 'X '=*•' ■■■-' ^^---O-"-. ^==^=^

Methodaftersetting channel^akes. Set a secondrow of stakes at so-foot intervals (closer on sharp curves) II feet

below channelstakes. This row marks firstplowing.

This drawing is based on use of a two-bottonn, l4,orl6'inch plow. RemoveJointers. Coulter maybe lefton. Use

sharp shares. Maintain enough speed to turn furrow slice completely over Remove crop residues and disk heavy

sodwe//beforep/ow/n¿.

Start firstplowing by throwing furrowslice againstlowerstake line. Return empty packing ferrâce.unless adjoining tandis to be plowedStar/eachsuccessive plowing with the front bottom picking up the third furrow slice (marked

wifh arrow) ofthe previous plowing. Crowdover ifnecessary so as fo form a smooth backslope.

/fterrace rid^e is not the desiredheight additional plowtngs may be necessary. To increase ^he size < width, additional rounds per p/oíYÍn¿ may he necessary

or

FIGURE 8.3 A METHOD FOR TERRACE CONSTRUCTION PLOWING FROM THE UPPER SIDE ONLY
8-8

Stoke Row

NOTE: Cuts 5" deep-18" wide (approx.)

6 % slope (approx.)

Hollow Place

See Chart Figure 8.1

SUGGESTED PROCEDURE

Run the rotor in the gear which will throw the main stream of dirt into the center of the terrace ridge.

1st Plowing

After setting channel stakes, plow the first trip 4 to 5' downhill from the stoke row and the return furrow 14 to 15' downhill from the stake row. The first trip and return

can be located by staking or by two men ««alking with a rod held between them. One of these men walks on the stoke row and the other man walks ahead of the plow.

2 nd Plowina

Thé 2nd plowing starts with the plow being one furrow closer to the center of the islond as indicated.

3 rd Plowing

In the 3rd plowing the upper side of the ridge should be started with the plow just below the ridge top as shown. On the lower side, plowing should start just below the

point where a hollow exists as indicated on the drawing.

4 th Plowing

This plowing may not be needed. Often times if soil conditions ore right, the first three plowings as indicated will build on odequote terrace. If the 4th plowing

is needed it should be started near the top of the ridge on the upper side. Furrows should ordinarily be shallow. On the lower side they should start just below

the toe of the slope. If the operator decides trips 3 04 are not needed to alleviate the channel on the lower side they may be mode as indicated "Alternate Trips"

on the upper side, throwing the soil either away from the channel with the rotor in high speed or scatter on the channel and ridge.

General

The plow should be set at a depth which will permit maximum tractor motor speed. This speed con be determined by the operating sound of the troctor motor. The speed

of the rotor should be maintained at maximum speea for the gear setting.

Variations from the above procedure may be desirable to get an adequate terrace. This will depend on the soil conditions and the tractor power.

FIGURE 8.4 A METHOD FOR TERRACE CONSTRUCTION WITH WHIRLWIND
8-9

each one to decide and to develop a good technique. The island

method with a moldboard plow is so widely used that it is further explained. It will require about 32 to ^0 rounds to construct a standard terrace^ about 14-5-50 rounds for level terraces.

Figure 8.2 shows a method for sequence of rounds. Experience has

shown that after the fifth series of rounds, or after 20 to 30

rounds, some deviations may be desirable due to the condition of

the soil, how the plow operates, and the experience of the operator. The main thing is to keep the plow as level as possible.

Drive at a rate of speed so that the furrows will be turned over

by the moldboard. Start out by plowing the first series of

rounds shallow. Then plow the next series about one inch deeper

so as to reach undisturbed soil. If the soil is "powder dry" or

too wet, it is advisable to delay construction until a favorable

moisture condition exists. If level terraces are to be constructed, set offset stakes so that the ridge of the completed

terrace will fall on the original staked line. (See Part 8.32.)

c. Moldboard Plow - From Upper Side Only

In using this method all of the soil is moved from the upper

side. This method puts the channel somewhat deeper into the

original soil. On soil where the highly pervious covering is

thin and drainage is needed, this is a desirable feature, as the

deeper channel tends to intercept horizontal movement of water.

On steep slopes this method has considerable merit. Figure

8.3 shows a method for sequence of roiinds.

d. Disk Plow or Disk Tiller

With the exception of not removing surplus vegetation follow the

same procedure as with the moldboard plow. (See Figures 8.2 and

8.3.)

e. Whirlwind Terracer

The whirlwind terracer will not work satisfactorily in rocky or

stony soil; neither will it work well in heavy sod. All heavy

vegetation should be removed. Heavy sod should be thoroughly

disked before starting the construction. To operate a whirlwind

terracer satisfactorily, a tractor that can handle a three- or

four-bottom plow is required. The plow should not cut deeper

than the tractor can pull without reducing the motor speed. This

will maintain the speed of the rotor necessary to throw the soil

on the ridge. The terracer should be kept level so that the

rotor can effectively throw the soil. It generally requires 30

to 35 rounds to complete a graded terrace, depending on the condition of the soil and size of tractor used.

A 10- or 12-foot island is recommended on the average fields,

(Figure 8.4). Here, again, local methods are different and some

operators start by throwing the soil together the first round.

The method illustrated, therefore, is merely a guide. A method

adapted to local conditions and the operator should be developed.
8-10

f. Bulldozer

The bulldozer has an advantage in many respects. It can be used

on very rough, stony, and eroded soils. The ditches can be

filled as part of the terrace construction operation. The bulldozer will operate under conditions in which other types of

equipment cannot efficiently function, such as in extremely

dried-out soils. Two methods have been used (Figure 8.5^ page

8-11). The area should be plowed before starting construction.

This will insure a more uniform terrace and will save time.

The roughing-in is accomplished by making three "cuts" and

"bucks." After the roughing-in is completed, two rounds or more

are made lengthwise to shape the slopes and sometimes one in the

channel is necessary to give the terrace its final shape and

cross section.

g. Motor-Patrol Type Grader

For heavy work this type of equipment does an excellent Job.

Where a contractor has enough work for a machine of this type,

it is very effective and efficient. A skilled operator can cut

a channel true to grade and very little follow-up will be required to remove high and low spots in the channel. See Figure

8.6, page 8-12, for a suggested sequence of trips.

h. Elevating Graders

Several types of elevating graders are being used with good success. The number of roiinds and sequences depends upon size of

machine and condition of the soil. The speed of the belt on

several machines can be varied to place the soil where needed to

bring the terrace to the required cross section.

This type of equipment will usually be used only by contractors.

Methods will vary; however, the cross section of the terraces

should conform- to the standard.

8.42 Time Required

Figure 8.7, page 8-12, gives the average time required for constructing terraces. Comparison between terraces built with a

motor patrol or bulldozer and other types is not possible. This

table includes time required for making cuts and fills for the

motor patrol and bulldozer but does not for other types of

equipment.

8.50 CHECKING FINISHED TERRACE

8.51 Method of Checking

The high and low points should be marked so that the necessary

corrections can be made. Prevent ponding in graded terraces over

0.1 foot deep. This is always a hindrance to operation of farm

equipment and it causes crop loss.
8-11

Cross Sechion of Terrace

STAGGERED CUT METHOD

FIGURE 8.5 A METHOD FOR TERRACE CONSTRUCTION WITH BULLDOZER
8-12

Progressive steps in oanstruoting a ohannel terrace

in the Midwest with a 10-foot blade terraoer« The

terrace is constructed from the upper side only.

FIGURE 8.6 A METHOD FOR TERRACE CONSTRUCTION WITH MOTOR PATROL

Feet Hours

Type of Equipment Per Hour Per Mile

Moldboard plow - 2 bottom 125 - 190 28 - 41

Disk tiller 170 - 190 28-31

Whirlwind 170 ~ 200 26 - 31

Motor patrol grader 180 - 220 24 - 29

Bulldozer 180 - 220 24 - 29

Elevating grader, small 180 - 220 24-29

Elevating grader, large 200 - 250 21-26

FIGURE 8.7 TIME REQUIREMENTS FOR TERRACING
8-13

When checking level terraces the ridge height should be checked

for proper elevations. The terrace checking is as important as

the laying out of a terrace. No terrace job should be considered completed until it has been checked.

8.60 TERRACE MAINTENANCE

8.61 The farmer should be encouraged to make an inspection periodically and after each heavy rain. Any breaks should be repaired and

the channel and ridge brought to grade.

a. Repairs in fills should be higher and broader than the old

portion to prevent over-topping or seepage.

8.62 It is essential that a good rotation be maintained, thus materially reducing the silting of the terrace channel. In fields low

in organic matter, terraces may require special maintenance.

8.70 PLOWING TERRACED FIELDS

In many areas research and observation indicate that plowing with

the conventional one-way plow, over a period of years, will eventually bench a terraced field. The profile between terraces eventually becomes hollowed out and a bench effect is developed. This

difficulty can be overcome by using the two-way plow. The small

amount of erosion between the terraces can be removed from the terrace channel and a constant profile, without benching, can be maintained.

Farmers should be encouraged to use the two-way plow.

8.71 How to Use the Two-Way Plow (See Figure 8.8, pages 8-15 and

8-16.)

Start the first step in this method of plowing by throwing the

first furrow on the ridge of the top terrace from the back-slope

side. The area below the top terrace is then plowed by turning

all the furrows uphill. (See Step No. 1.)

When the narrowest place is within about 15 or 20 feet of the

channel of the next terrace, the wide areas should be plowed out

leaving a strip of unplowed land of even width through the field.

After all the wide areas are plowed, a land I5 or 20 feet wide

will be left above the terrace channel. This should be plowed

out by turning the furrows uphill as shown in Step No. 3.

The last step (Step No. k) consists of plowing the area between

the top of the ridge and the low point of the channel. This is

done by throwing the first furrow toward the top of the ridge

and continue throwing furrows in the same direction until this

land is plowed out. This method will result in one dead furrow

which occurs in the bottom of the terrace channel and one backfiirrow which will occur on the ridge.
d-lk

The area above terrace number one and the area "between other

terraces should be plowed using the same sequence.

After several plowings, using a two-way plow, the ridge maybecome too high. This can be prevented and tne terrace broadened by leaving the backfurrow to one side or the other of the

extreme peak.

8.72 How to Use the Conventional One-Way Plow

a. Method 1 - Dead Furrow Between Terraces (See Figure B,9^

page 8-20.)

The first step in this method is to backfurrow to each terrace

ridge. If the terrace has lost some of its height, throw the

furrows together at the top Just like a land would be started

anywhere. If the terrace ridge is already high enough, keep the

plow below the ridge so that the disturbed soil from the first

round just meets at the top. This helps to broaden the top of

the terraces and makes them easier to farm.

Continue plowing on the land started with the backfurrow until

an area about 20 feet above and 20 feet below the terrace ridge

is plowed. When this has been done on each terrace, plow the

remaining areas between the terraces as separate lands.

Continue to plow these lands until the unplowed strip narrows

down to about 20 feet wide at the narrowest part (Step 2). This

unplowed area will be irregular in width.

Plow extra furrows on the wide portions of the remaining area

until a turnland 20 feet wide extends through the entire length

of the field (Step 3), This permits irregular areas to be

plowed out without turning on plowed groimd.

This uniform width tiirnland can then be plowed as a regular land

and will leave the dead furrow about halfway between terraces

(Step h). The turnland can be narrower than 20 feet if small

equipment is used and should probably be wider if large plows

and tractors are used.

With this method of plowing, as illustrated, the furrow will be

thrown into the terrace channel and the dead furrow will occur ^

in the same place every time the field is plowed. Since that is

not desirable, this method of plowing should be alternated with

Method 2.

b. Method 2 - Dead Fiorrow in Terrace Channel (See Figiire 8.10,

page 8-21.)

Every other time the terraced area is plowed it is important to

throw the furrow away from, rather than into the terrace channel,

This is done by backfurrowing from the terrace ridge to the

center of the terrace channel on each terrace (Step 1).
8-15

The best way to plow terraced land is with a two-way plow - a plow that has two sets

of moldboards and permits throwing the dirt either to the right or to the left. Continuous

plowing with the conventional plow will eventually bench a field. The drawing below, exaggerated for clarity, shows what happens to a terraced field after a number of plowings with

conventional plows« Even though the dead furrows are shifted from one place to another you

can't avoid throwing soil both downhill and uphill which is what causes benching of the

fUld.

ONE-UJflV PLOUJ /METHOD

BftCK-FURROUU

BflCKFURFlOU)

IN O'SING <q ONE-UJ(qV PLOUJ THE PßOFlie B€CO/^ES DISHED RND fRFTEC a (MU/7\BECL

OFPUOUJINGS THE TfQI^<^CEÇ BECO/TAE-'PENCHED' -flQQOUJÇ /ND|Cî:ïT-E DIRECTION

DIPT IS TMROUÜN ---DOTTED LINE. INDIC-^TES NPTUßAU GQOUí>JD LEVEL "

The two-way plow makes it possible to keep the terraces about as you built them as

shown by the drawing below. Soil is thrown toward the terrace ridge and the dead furrow is

always left in the terrace channel. This can be done only with the two-way plow.

Farmers who have terraces or plan to terrace should give serious consideration to the

effect that plowing has on a terraced field. When the old plow wears out they should buy

the two-way plow.

See the drawings on the back for steps in plowing terraced land with the two-way plow.

TUüO'üUflV PLOUU /AETHOD

rBACI^FÜRROU;.

rBf^CKruRAOUJ

DFADPUftROCU

BV USING a TLUO-tJünV PLOUJ TH£ PRO-TILt Oe/AAINJÇ fM.f¡\0%T CONSTí^NT - - -

flRROUJS ÍNOlCf^TE DIRECTION DIÍ^T IS THROtüN - DOTT€D LINE ÎMDICl^TEÇ

NATURAL GROUND LEVEL. -

FIGURE 8.8 A METHOD! HOW TO PLOW TERRACED LAND WITH THE TWO-WAY PLOW
8-l6

HOW TO PLOW TERRACED LAND WITH THE TWO-WAY PLOW.

..)i...

ST€P NQ I

PLOUJ OP€A BETU)€€N TERRACe«

^1

ÇT€P NQ 2

PLOUU OUT UJtDE fíñ€fíC I

STCP(^3

I PLOLÜ ftC/AOtNING LAND ABOV€ T€00«C€. CHANNEL \

ST€P MO. 4-

ITHDOUJ DE/AfllNING FüRftOUJS TOUJ«BD TERRACE R«DOE

FIGURE 8.8 A METHOD. HOW TO PLOW TERRACED LAND WITH THE TWO-WAY PLOW
8-17

Then move up the slope 15 or 20 feet from the terrace channel

and start another backfurrow parallel to the terrace channel

(Step 2) . The line to follow in laying this backfiirrow can be

done by eye after a little experience. It may be desirable to

set a line of stakes the first time a farmer tries it, but after

experience this will not be necessary. Continue to backfurrow

this land until the dead furrow is reached in the terrace channel. The dead furrows formed there will materially increase the

capacity of the terraces.

There is an iinplowed area below each terrace which can be plowed

as outlined in Method 1, Figure 8.9. Work the remaining land

down to an even width strip 'and plow out as illustrated on the

right in Steps 3 and 4. The same procedure is followed on all

the terraces.

It is important to see that the dead furrows fall in a different

place each time the field is plowed. The easiest and best way

to do this is by alternating plowing Methods 1 and 2 and by varying the width of the plowed strip between the terraces. Plowing

according to Method 2 throws the fxirrows out of the terrace channel .

Always plow out point or irregular-shaped areas before plowing

all of the long ones. This gives solid or \mdisturbed ground to

turn on, resulting in less wear and tear on equipment.

8.80 PEEPAEING-SEEDBED AI© PLANTING CEOPS ON TEEEACED LAND

8.81 All seedbed preparation should be carried out by using the

terrace as a guide line for starting operations.

8.82 Planting Eow Crops on Terraced Land

a. Method 1 (See Figure 8.11, page 8-22.)

When planting row crops such as corn or beans, start planting on

the uphill side of the top terrace (Step l) . Don't straddle the

terrace with the planter. Put the first row just off the terrace

ridge on the uphill side. Continue planting to the top of the

slope. Straddling the terrace ridge with the planter will cause

trouble later in cultivating - the front shovels will be buried

while the rear ones are dangling in the air.

After planting above the top terrace to the edge of the field,

continue the planting by starting on the ridge back slope of the

top terrace and plant down the slope about one-third of the distance between the first and second terrace (Step 2).

Then go to the channel side of ridge of the second terrace and

plant up, just as with the first one, until a strip of land

eight rows wide at the narrowest part is left unplanted (Step 3).

This remaining area yet to be planted will almost certainly be

irregular in width.
8-18

Now plant extra (shorter) rows on the wide portion of this

remaining area iintil the eight-row width of turnland extends

through the entire length of the field (Step k). This permits

planting the irregular areas without turning on planted ground.

This procedure is necessary when planting is done with a hardor loose-ground lister.

The eight-row width turnland is planted last, giving eight rows

that go through the entire length of the field (Step 5). The

width of tnis turnland may vary but eight rows are enough for

either a two-row or a four-row planter.

Many prefer this method because no turning is done on planted

ground, and a better contour is maintained. In harvesting pick

the eight-turn rows and disk them down. This leaves a turning

area for picking the point rows.

b. Method 2 (See Figure 8.12, page 8-23.)

Another method is to start planting on the channel back slope

of the top terrace and continuing to the top of the slope or

field boundary (Step 1).

Then start planting on the channel side of the ridge of the

second terrace. Plant uphill until a land eight rows wide at

the narrowest portion is left unplanted on the back slope of the

next terrace above (Step 2).

The remaining area yet to be planted will be irregular in width.

Next, plant extra (shorter) rows on the wide portions of the

remaining area. This will leave an eight-row width of turnland

extending through the entire length of the field (Step 3). Here

again this permits the irregular areas to be planted without

turning on the planted ground.

The final operation is that of planting the turnland. To do this

start near the top of the ridge back slope of the top terrace and

plant down eight rows (Step h). The only difference between this

method and the first is in location of turnland. In this method

the eight-row turnland is left Just below each terrace instead of

halfway between terraces.

Many farmers prefer this method because:

(1) It can be carried out without turning the equipment on

planted ground. This is of considerable importance if you

plant your corn with a hard ground or a loose ground lister.

(2) Many farmers find this method of planting easier to

explain and more easily understood by the hired man.

(3) With the eight-row turnland area located on the back

slope of the terrace it is easier to start picking on rows

that extend the entire length of the field.
8-19

The establishing of the eight-row tiirnland area in both Methods

1 and 2 of planting is easily done by eye after a little experience in doing it. Here, as in plowing, it may be desirable to

set tvo lines of stakes the first time the farmer tries it - one

line of stakes in the upper side and the other line on the lower

side of turnland. With added experience this will not be necessary.

c. Method 3 (See Figure 8.13, page 8-24.)

A third way to put in row crops is to start planting (Step l) on

the inside slope of the top terrace and planting to the top of

the slope or field boundary just as in the other methods. Then

start on the back slope (Step 2) of the top terrace and plant

down to a point approximately one-half the distance to the

second terrace.

Next (step 3)^ start planting near the top of the channel back

slope of the second terrace, planting uphill until the rows join

those already planted. This will leave point rows near the center between terraces. (An alternate method of planting point

rows is to plant from both sides rather than from one side as

shown.) Continue this procedure with the remaining terraces.

When planting is completed to the last terrace, use it as a

guide line and plant to the bottom of the field. Where loose or

hard groxind listing is done Method 3 is not recommended because

of turning on planted groimd.

d. Method k (See Figiire 8.14, page 8-24.)

Another method that could be used is identical to Method 3,

except that the uneven area occurring near the center between

terraces is not plowed but is left in sod crops. A temporary

crop which can be harvested for hay can be used in the uneven

area if it is plowed with the rest of the area. This procedure

will work all right, but it is very seldom used or recommended.

NOTE: Any method whereby point rows occur in the terrace channel should be avoided and certainly not recommended.
8-20

METHOD 1 - LEAVING DEAD FURROW BETWEEN TERRACES.

ÇT€P NO. I

ÇT€P NQ 2

PLOa» AROUND AREA BClTOUetN TERRflCCS UNTIL

UNPLOIUED SECTION )S ^0'Al N^UROUüB.'^J PO/NT

ST€P NO. 3

FOLLOUU €XIÇTING FURAOUJÇ • TOÎIiTi

TURNLflMD OOLUíN TO UNIFOR/Tv ULXDTH

..^^^^^ _^r?£^^^^^i§»^ 1

ÇTEP NO. A

IPLOLU /:ïROUND TURNLflND AND I

kcflve DE^DFUiicou; IN CCNTE«

FIGURE 8.9 A METHOD! HOW TO PLOW TERRACED LAND WITH THE CONVENTIONAL ONE-WAY PLOW
METHOD 2 - LEAVING DEAD FURROW IN TERRACE CHANNEL. 8-21

ST£P ÑO. I

I BflCKf^UPkUOUU JPnOm T€DRflC£ UlDGE I

our TO C€NT€R OF TERRACE CHANNEL

«\^^ç^

^^\VJO^^^

"^^^;»«*i?c^

T€R««C€. «RER

rCTflßT BflCKFURPOUJ;'J6 flBOV£ TECRflC€

IS'OQ 20'FR0/A TH€ CHflWNEL DEflDFUPOOlU

COivriNUE UNTIL THE CHANNEL 19 OEOCHED-i

STEP NO 2

STEP NO. 3

IPLOUJ AROUND flREfl BETUJEEN TERRACES UNTIL I UNPLOUJED SECTIOM IS 20'AT NflROOLUEST POINT

ZÍ

ÇTEP NO. 4

IfOLLOO) EXISTING FURROUJS AND TPI/A I

TUQNLflND DOUJN TO UNIFOR/A UJIDTH

zi

STEP NO. 5

PLOtU OUT THE TUCNLfKVDl

^^^M^^^^^^Ä

It is advisable to alternate this method with the first method described on the opposite page

FIGURE 8.10 ANOTHER METHOD. HOW TO PLOW TERRACED LAND WITH THE CONVENTIONAL

ONE-WAY PLOW

259293 O - 53 - 10
8-22

ST€P NO. I

HERE'S

ONE

START PLANTING N€«0 TOP Of pIDGE

rCONTlNUe TO TOP Of= SLOPE OR BOUNDflRV i

2aPT€BRRCESTEP NO. 2

rCONTINUe PLANTING BV STflO.TIN6 ON BOCKSLOPE OF TOP TERRflCG flND

PLANT DOLUN ABOUT ONE THIRD OF DISTANCE BETlUEEN I« 4 2îu» TECROCES -

WAY

STEP NO. 3

STOP.T PLANTING NEAR THE TOP OF RiDGE OF SECOND TERROCE AND PLANT UP THE SLOPE-i

j-OVER CHRNNEL, UNTIL fl LAND S ßOlUS LÜIDE AT NflPPOUJÊST POBTION IS LEFT UNPLflNTED

ST€P fMQ 4

I PLANT'SHORTER' ROOIS ON CUIDE POßTlON OF THE TURNLflND I

UNTIL EIGHT POLU TURNLflND EXTENDS THE LENGTH OF FIELD

STEP NO. 5

I THE Ö ROUJ UJIOE TURNLflND IS PLANTED LAST I

AND EXTENDS: THßOUGH ENTIRE FIELD LENGTH

FIGURE 8.11 A METHOD FOR". PLANTING ROW CROPS ON TERRACED LAND
8-23

ST£P NO.

START PLANTING N€flO TOP Of PIDGE

rCONTINUe TO TOP OF SLOPE On BOUNDflRS' I

LHaPTERRfiCESTEP NO 2

START PLilNTIMG /M€«R THE TOP OF RIDGE OF SECOND TERRACE AND PLANT UP THE SLOPE-i

rOVER CHANNEL, UNTIL A LAND Ô ROUJS LUIDE AT NflRROUJEST PORTION IS LEFT UNPLANTED

ÇT£P MQ 3

I PLANT 'SHORTER ROLJUS ON UUIDE PORTION OF TURNLAND I

UNTIL EIGHT ROUJ TURNLAND EXTENDS LENGTH OF FIELD

STEP NQ 4

-START NEAR TOP Of BACkSLOPE OF TOP

TERRACt AND PLANT DOLUN Ö ROUJS

FIGURE 8.12 ANOTHER METHOD FOR! PLANTING ROW CROPS ON TERRACED LAND
8-2l^

ST£P NO. I

STrtRT PIANTIN6 l«»MJ TOP Of DID6E1

rCONTINUe TO TOP OF SLOPE OA BOUNDRV

^

T€RRflCe 'AREA

-ZarTCRRACEÇT€P NQ 2

-CONTINUE PLANTING BV STARTING ON BflCkÇLOPE Of TOP TEPRflCE. AND

PLANT DOIÜN ABOUT ON£ HALf Of DISTANCE BETUJEEN l«*-2<» TERfiACESSTEP NO 3

START PLANTING NEAR THE TOP Of RIOGE Of SECOND TERPOCE. AND PLANT UP THE ÇlOPE-,

rOVEß CHANNEL^ TO PREVIOUS PLANTED ROU/S LEAVING POINT ROU« IN BETU)EEN TECRACEÇ

FIGURE 8.13 A THIRD METHOD FOR! PLANTING ROW CROPS ON TERRACED LAND

I AREA IDHERE POINT ROlüS UiOULD OCCUA IS ESTABLISHED ANO ßCTAINEDi

IN SOD CfiOPS OR SCCOEO ID GRAIN UJHEN RCST Of AREA IS IN ROO) CROP9

If you don't want to bother with point rows you can

just leave the uneven area in meadow or small grain

FIGURE 8.14 A FOURTH METHOD FOR! PLANTING ROW CROPS ON TERRACED LAND
8-25

8.90 HAEVESTING CEOPS ON TEEEACED LAITO

8.91 Harvesting Grain (See Figure 8.15, page 8-26.)

Grain crops will either be harvested with a binder, a windrower, or

cut direct with a combine. All of these operations present the same

general problems. On land that slopes 6 percent or less, standard

terraces built according to specifications (see Figure 8.1, page 8-3)

can be crossed with machinery at almost any angle. The easiest way

to harvest grain on such terraces is simply to cut around the field,

as would be done if the terraces were not there. On the steeper

slopes, where terraces cannot be built wide, it is probably better

to harvest the grain with the terraces. This will cause some waste

where the tractor and bull wheel knock down the grain. If terraces

are nearly parallel it would be well to select one key terrace -

usually near the center terrace. A land can then be opened on this

terrace. With a binder or combine this will simply mean back cutting on the terrace ridge selected for a key terrace. With either

of these machines it is best to put the grain wheel on the terrace

ridge and make a complete roimd.

If a windrower, which delivers the grain to the center, is available

the job is easy since only one back-cut through the field with the

windrower is necessary. It is probably better to make this cut with

the grain wheel running on the top of the terrace ridge. When using

an old converted binder for a windrower, the better plan is to cut a

strip through the field on the key terrace with a mower and use it

for hay, or put it into a windrow with a side delivery rake after

the first cut is made. The remainder of the terraces can be cut

with the machine running parallel. By planning ahead, wide cuts can

be made on the areas which have wide horizontal interval and narrow

cuts made on the narrow interval. In this way the cut will approach

the next terrace with the cut parallel to the ridge.

8.92 Harvesting Corn (See Figure 8.I6, page 8-27.)

The method of picking corn on terraced land depends largely on how

the field was planted. It will be the reverse, so to speak, of the

corn planting procedure. Only one method is shown in detail which

is for picking corn planted according to Method 1, Figure 8,11,

page 8-22. Others will be very similar and, in any event, will be

the reverse of the planting process.

First open up a land by picking the rows in the eight-row turnland.

With a two-row mounted picker this is very simple. With other

pickers it will be necessary to contend with down rows.

The short or point rows should be picked next (Step 2). They can be

picked very easily by using the eight-row turnland to provide a

place to turn equipment.

Next, as illustrated in Step 3, harvest all the long rows between

the turnland and terrace number 2. As in the harvesting of the

short rows, the eight-row turnland will furnish an adequate turnland

for harvesting these rows.
8-26

SMALL GRAIN

On land that slopes less than about 6 percent terraces ari built wide enough to let you

cross them with machinery at almost any angle you choose. Thus you can cut such fields

by going'round and'round them just as you always do. On steeper slopes, where terraces

can't be built wide, it is probably better to harvest the grain with the terraces. The

three drawings below showing a windrower in operation illustrate how this may be done.

£.Jliiii^

ST€P ÍNQ I

I OPEN LAND ON TOP OF SECOND TERRflCtl

il----iltilMiaiiil^..,i^^

E NUMBER ONE J U^U^aC^ ^,U^BE« TU,0 t tr^iñt ^,^BE« T«CEE" TEBCflCE NUMBER THCEEJ

I

^, ^

ST€P NO. 2

CUT LAND UNTIL TERRACES ONE AND THREE ARE flPPROPCHED |

4--^

- TERRflCe NU/ABER ON€. VUINDBOUÄ fCOff\ CUTS OF STEP NQ t - T€RR<ïC£ MU/7\8€R THREE.-

STEP NQ 5

I CUT OBBOUND THE «REO LEFT ABOVE, AND INCLUDING,TEBBflCt NUffSBEC ONE

3

Sïlli^lpiiWïïil3^|\

LTFDDöCE -TEPOACE MU/ysBE42. NU/rNBE4iONE ON —I

FIGURE 8.15 A METHOD FOR! HARVESTING CROPS ON TERRACED LAND (SMALL GRAIN)
8-27

CORN

Harvest row crops in reverse of the way the field was planted. The illustrations below

show how to harvest corn where the turn land was planted between the terraces.

STEP NO. I

mííiimkmmmime

OUT TURN LAND FIRST

Cf

ST€P WQ 2

PiCK "SHOOTER' ROOIS ON UJIDE POHTION OF TUONLflNO j

sTcp m 3

hr///-/r^'rn ram ' ;->->- '

I PICK CORN LAND BETUJECN TURNLflND AND 2^ T£DPflC€ RID6E I

lli#ICi^fe«.

ST€P m 4

I PICK ALL CORN flBOVe TURNLflND TO fl£LD BOUNDRV I

FIGURE 8.16 A METHOD FOR: HARVESTING CROPS ON TERRACED LAND (CORN)
8-28

The last step illustrated will be to harvest the rows up to and

above the top terrace. Usually it is better to open a land in this

area by picking around the area containing the long rows. This is

illustrated in Step k. After the long rows are harvested any short

rows that remain along the field boundary can be harvested as a land

by working around the remaining corn. By harvesting the long rows

first, adequate turning area is provided for picking these short

rows.

The remainder of the terraces are harvested as indicated in Steps 1,

2, and 3, and the area below the last terrace can be harvested by

lands as is done in picking an ordinary field. It is well here, as

in picking out the top terrace, to pick the long rows first, so that

adequate turnlands are provided for harvesting the short rows.

Some details which apply to corn harvest in terraced fields in general are:

(1) The method of adapting picking to the various planting

methods is to study the charts for planting and use the reverse

order,

(2) On all methods of planting, harvest the long rows first.

This leaves a good-sized area of picked corn to turn on in harvesting the short rows.

(3) Where a mounted picker is used and the wagon is pulled

behind the tractor, wide sideboards will be needed so that corn

will not fall on the ground.

{k) On the mounted type picker a shut-off of the elevator

should be provided for short curves.

(5) The procedures for harvesting corn for silage can follow

the same steps as for picking corn.

8.93 Harvesting Hay

Techniques used in cutting hay are similar to those used with grain.

On land sloping up to about 6 percent, hay should be cut Just as

though the field were not terraced. On steeper land it will be better to open up lands on the terraces and work each terrace as an

individual unit. Using a side delivery rake presents the most difficult problem. The best starting position is to work the hay down

from the top of the terrace ridge. This will leave one windrow in

the bottom of the terrace channel and one on the ridge back slope.

Both of these are easily picked up with a hay loader. If the short

windrows are made and picked up in connection with the last long

windrow, much excess driving in the field will be avoided.
9-1

PAET 9

DIVERSIONS

9.10 GEOTŒIAL

9.11 Definition and Purpose

A diversion is an individually designed channel constructed

across the slope for the purpose of intercepting surface runoff

and conducting it to a safe outlet,

9.12 Diversions are used:

a. To reduce the length of slope.

b. To divert water out of active gully overfalls.

c. To divert vater away from farm buildings.

d. To protect bottomland from overflow.

e. To cut off headwater from the top terrace where the land

above is not terraceable because of topography or land ownership.

9.13 Some points of importance to consider in use of diversions are:

a. Drainage areas must be in grass, adeq\iately supported by a

rotation, strip cropped, or terraced, otherwise large soil losses

will fill the channel. Filling of channels is the reason for

most failures.

b. Diversions should ordinarily not be of a greater spacing on

strip-cropped fields than the width of three strips.

c. Diversions and outlets must be designed so that velocities of

the water will not exceed that allowable for the type of vegetation present.

d. Diversions should not be used as a permanent control on

fields which can be terraced.

9.1^ Location and Spacing

a. Where diversions are used with strip cropping to reduce the

length of slope, the spacing as set up in the technical operations plan should be used. The spacing will vary according to

soil type, location, width of strips, and the rotation used.

b. In the control of gullies and diverting water from farm

buildings two factors are important in the location of diversions:
9-2

(1) Locate far enough above the lip of the gully overfall

so that stable slopes will exist after sloughing has taken

place.

(2) Locate so that outlet water will be spread and velocities will be kept low enough for a safe outlet or construct

an outlet in accordance with specifications for grassed

waterways (see Part 10) or use a permanent structure for the

outlet,

c. Where diversions are used to protect bottomland from overflow, the diversion should generally be located Just above the

cropland area. The principle for the outlet design is the same

as above.

9.20 DESIGN OF DIVERSIONS

9.21 Diversions should ordinarily be designed to keep velocities as

high as will be safe for the type of vegetation which will be

present in the channel. Ordinarily safe velocities are:

Bare channel

Sand - 1.5 feet per second

Other - 2.0 feet per second

Poor channel vegetation - 3 feet per second

Fair channel vegetation - k feet per second

Good channel vegetation - 5 feet per second

9.22 Steps in Design of Diversion

a. Determine the watershed area at the outlet of the diversion

and at such other points where it is desired to change the grade

or cross section.

b. Obtain the maximum rate of runoff for 10-year frequency.

(Eefer to Figure 3.1.)

c. Determine the channel size and grade (Figure 9.1). From the

chart select bottom width, depth, and grade for the required runoff, based on safe velocity for the type of vegetation planned

for the divers*ion. One important item to consider is that

velocities should be based on channel vegetation. In most

cases this will mean that you will either design for a low

velocity based on bare channel or a high velocity based on

degree of vegetation. Usually poor vegetation will not be a

permanent condition and therefore chann.els should not be

designed on this basis.

d. For designs not covered in Figure 9.1^ an engineering technician should be consulted.
o

c

X

m

CO

o

<m

XI

CO

o

z

om

O)

Ci

o

>

3>

DEPTH IN FEET REQUIRED FOR DIVERSIONS WITH 4 TO 1 SIDE SLOPES

IW ZW BOTTOM

WIDTH 4' 6' 8' 10'

%#< 0.2 0.4 0.6 08 1.0 1.5 2.0 0.2 0.4 0.6 0.8 10 1.5 20 0.2 0.4 06 08 1.0 1.5 2.0 0.2 0.4 06 0.8 1.0 1.5 2.0 ACRES ACRES

5 0.8 06 0.6 0.5 0.5 0.4 0.4 0.6 0.5 0.5 0.5 0.4 0.4 04 0.6 0.5 0.4 04 0.4 03 0.3 0.5 0.4 0.4 04 0.3 0.3 03

10 1.0 0.9 0.8 0% 0.7 0.6 0.6 0.9 0.8 0.7 W 0.6 06 0.5 08 07 0.6 ^^ 0.5 0.5 05 07 0.6 0.5 ^ê 05 04 0.4

15 1.2 I.I 1.0 0.9 09 0.8 0.7 I.I 0.9 0.8 0% 0.7 07 0.6 10 0.8 0.7 07 07 06 0.6 09 0.8 0.7 0% 0.6 05 05

20 14 1.2 I.I 1.0 1.0 0.9 0.8 1.3 1.1 1.0 0.9 09 0.8 0.7 1.1 1.0 0.9 08 0.8 07 0.6 I.I 09 08 07 07 0.6 0.6

25 1.6 1.4 1.2 1.2 I.I 1.0 0.9 1.4 1.2 I.I 1.0 LO 0.9 0.8 1.3 I.I 1.0 0.9 0.9 08 0.7 1.2 1.0 0.9 0.8 0.8 0.7 06

30 1.7 1.5 1.3 1.3 1.2 I.I 1.0 1.5 1.3 1.2 I.I 1.0 0.9 0.9 1.4 1.2 I.I 1.0 0.9 0.8 0.8 1.3 I.I 1.0 0.9 09 0.8 07

35 1.8 1.6 1.4 J4 1.3 1.2 I.I 1.7 1.4 1.3 1.2 I.I 10 1.0 1.5 1.3 1.2 I.I 1.0 0.9 08 1.4 1.2 I.I 1.0 0.9 08 08

40 1.9 1.7 1.5 IT 1.4 1.2 1.2 1.8 1.5 1.4 ^

1.2 I.I 1.0 1.6 1.4 1.2 'i I.I 1.0 09 1.5 1.3 I.I I.I 1.0 0.9 08

45 2.0 1.8 1.6 1.5 1.4 1.3 1.2 1.9 1.6 1.4 1.4 1.3 1.2 I.I 1.7 1.5 1.3 li 1.2 1.0 1.0 1.6 1.3 1.2 's' 1.1 1.0 0.9

50 1.8 1.7 1.6 1.5 1.4 1.3 2.0 1.7 1.5 1.4 1.4 1.2 I.I 1.8 1.5 1.4 1.3 1.2 I.I 1.0 17 1.4 1.3 1.2 I.I 1.0 0.9

60 2.0 1.8 1.7 1.6 1.5 1.4 1.9 1.7 1.6 1.5 1.3 1.3 2.0 1.7 1.5 1.4 1.3 1.2 I.I 1.8 1.6 1.4 1.3 1.2 I.I 1.0

70 2.0 1.8 1.7 1.6 1.5 2.0 18 1.7 1.6 1.4 1.3 1.8 1.6 1.5 1.4 1.3 1.2 2.0 17 1.5 1.4 1.3 1.2 I.I

80 $s 1.9 1.7 1.6 1.9 1.8 1.7 1.5 1.4 1.9 1.8 1.6 1.5 1.4 1.3 1.8 1.6 1.5 1.4 1.3 1.2

90

—Táh"

2.0 1.8 1.7 20 1.9 1.8 1.6 1.5 2.0 1.9 1.7 1.6 1.5 1.4 1.9 17 1.6 1.5 1.4 1.3

100 _JK1_ 1.9 1.8 2.0 1.9 1.7 1.6 2.0 1.8 1.7 1.6 1.5 2.0 1.8 17 1.6 1.4 1.3

120

-iOp2.0 1.9

HlH

^n^ 1.9 1.7 ^^ 1.9 17 1.6 2.0 ^i 17 1.6 1.5

140 2.0

"tsn

2i> 1.9

-141-'

W 1.8 17 2% 1.9 17 1.6

160

"iër"

2.0

"iSr^ ^ê 1.8 ^ñ^ 1.8 17

180

—16]-

1.9

—l2r~'

1.9 1%

200 2.0 2.0 1,9

WTE- DARK LINES ACROSS CHART INDICATE VELOCITIES. FIGURE IN LINE GIVES VELOCITY. ALL DEPTHS ABOVE OR TO LEFT

OF LINE WILL BE OF LESS VELOCITY.

THE ABOVE ARE MINIMUM DEPTHS. ON LOCATIONS WHERE SILTING WILL OCCUR 0.3'TO 0.5' FREEBOARD SHOULD BE PROVIDED DEPENDING ON THE SEVERITY OF THE SILTING.

DESIGN DATA: n = 0.04 MAXIMUM DEPTH 2.0'.

EXAMPLE^ FROM CHART 3-L-I4054 0 = 53 CU. FT./SEC. - USE 0=50

MAXIMUM VELOCITY BASED ON VEGETATION 3'/SEC.

DEPTH REQUIRED FOR 6' BOTTOM CHANNEL =1.5' WITH 0.6% SLOPE IN CHANNEL *

MOTHER BOTTOM WIDTHS COULD HAVE BEEN USED.

COMPILED BY: P. J. 4-2-47. CHECKED BY: H.W. F. - E. W. W. - E. A. Z.

3-L-I5085
9-4

9.30 LAYOUT AND CONSTRUCTION OF DIVEESION CHANNELS

9.31 When to Construct

The best time to build diversions is when the watershed area is

mainly in grass so that channel silting and runoff will be at a

minimum.

9.32 Layout

Use the same general procedure in laying out diversions as is

used in terraces. A \iniform grade may be used throughout length

or the grade may be changed as you go upstream. If the latter

is done^ the size should be determined at each point the grade

is changed.

9.33 Keeping Notes of Layout

The notes should be kept in a standard field book and should

show the watershed area and estimated runoff in cubic feet per

second; also, the recommended channel size and slope should be

shown.

9.3Í4- Method of Construction *

After the diversion is staked it can be constructed similar to

a terrace. (Part 8.4)

9.35 Checking Construction

Level shots should be taken on the channel and ridge to check on

the finished grade and ridge height. Checking is important to

determine the adequacy of the completed job. Keeping notes of

level readings serves as a permanent record in case there are

future questions. (Eefer to instructions. Part 8.5.)

9.40 MAINTENANCE OF DIVERSION CHANNELS

9.^1-1 Vegetate Channel and Upper Back Slope

Use the method outlined an detail imder vegetated outlets and

watercourse (Part 10) for establishing vegetation. Establishment of good channel vegetation is essential unless the channel

was designed for bare channel conditions.

9.42 Annual Mowing of Channel

Mowing of the diversion channel is essential, otherwise briars

and other brushy growth may obstruct flow. When woody growth

gets too large, mowing is impossible and the diversion channel

gradually becomes ineffective and generally results in failure.
9-5

9.ÍI-3 Removal of Silt

The channel may require maintenance due to silt accumulations.

Small silt deposits may be removed with a shovel or slip scraper.

However^ if the silt deposit extends for the full length of the

diversions, the channel should be plowed out as in terrace maintenance plowing. Excessive channel silting generally indicates

inadequate supporting vegetative practices.

9.^^ Repair Rodent Holes and Breaks

Diversions^left in permanent vegetation sometimes attract

rodents, particularly ground hogs. The ridge should be examined

at the time of mowing and if any breaks or holes are observed^

these can be repaired with'a shovel. A rodent hole is easy to

repair if it is done immediately. However, if the water breaks

through, it may erode to such an extent that considerable effort

and time are necessary to make the repair.

^.:^±sL=^. h--^--f--^-^
10-1

PAET 10

VEGETATED OUTLETS AND WATERCOUESES

10.10 WATEE DISPOSAL

10.11 Vegetated Watercourse

a. The grassed watercourse is one of the most common and "basic

conservation practices generally recognized^ accepted^ and practiced by the fanner. "Wherever there is rainfall, there are conditions under which a surplus of water will pass over the land

in the form of runoff. The success of any soil conservation

program depends on the removal of this surplus water without

damage to the land.

b. The safe removal of surplus water is a problem common to

every farm. The accumulated flow from only a few acres is sufficient to cause movement of soil to the extent that a gully is

started. The need for a lined channel to transport concentrated

runoff without damage to the land is obvious.

c. The success of a vegetated watercourse will depend on the

proper shaping and preparation to produce conditions favorable

to vegetative growth. Since vegetation is subject to deterioration through abuse and -unfavorable seasons, it is also necessary

to provide maintenance. Between the time of seeding and actual

establishment, a watercourse is unprotected and subject to considerable damage unless special protection is provided. Therefore, it is important to meet the required dimensions within a

reasonable degree.

d. Vegetated watercourses are of several shapes or cross sections - trapezoidal (flat bottom), parabolic (saucer or dishshaped bottom), or 'V shaped. In general, the saucer-shaped

watercourses are the most common in the region. Most of those

constructed with the trapezoidal section end up as parabolic

after a period of years. The "V" type is used in special situations .

e. Also of major importance for the successful establishment and

maintenance of a vegetated watercourse is the conservation treatment in the watershed. The better the erosion control effected

in the watershed the less the silting problem in the watercourse.

10.12 Watershed, Sketch Map

a. Terraces or diversions will normally change the surface

drainage pattern. For this reason it is necessary to know approximately the final layout before estimating the amount of runoff

the outlet will be required to handle. Since the outlet will be

constructed previous to the terraces or diversions, it is essential that a determination of additional area, which will be
10-2

diverted into a waterway^ be made before trying to estimate the

runoff. (See Part 8.20.)

b. The watershed map can be completed after changes in nonnal

surface watershed pattern are deteimined. Usually the natural

watershed divides can be determined by field inspection and

sketched on the aerial photo map.

10.20 WATERCOUESE LOCATION

10.21 Natural Draws

a. In general^ the most satisfactory location is in a natural

watercourse. Here the slope of the channel is usually the flatest in the watershed. Natural land slope confines the flow; is

in effect like sideboards^ and eliminates the need for freeboard. Soil and moisture are usually most favorable to vegetative growth. This location interferes less with operations when

it is necessary to cross the outlet.

b. Because of natural shape^ these watercourses are the parabolic type of cross section.

10.22 Fence Eow and Eidge Lines

a. This location uöually is parallel to a fence line or following a ridge. This makes it necessary to construct an artificial

channel. This location is sometimes used to eliminate an outlet

in the central part of a field:

(1) To outlet terraces or diversions that cannot be extended

to a natural draw.

(2) To provide an outlet away from buildings or other critical areas.

(3) ' To avoid using a natural draw which has a gully that

would be expensive or impractical to control.

b. The constructed watercourse shape will generally depend on

the type of equipment used to build them. While the chart used

for design is based on the parabolic cross section^ the watercoiirse may be built to trapezoidal or flat 'V section, depending

on conditions, and using the dimensions from the design chart.

Side slopes of U:l should be used for the trapezoidal shape in

construction, with a flat bottom width to "fit" the over-all top

width from the chart.

10.30 DESIGN

10.31 Velocity of Flow Is the Basis of Design

a. The design of a watercourse is the determination of channel

dimensions so that the estimated flow will be discharged without
10-3

damage to the channel or the lining. The lining here considered

is vegetation which can vary as to type and density. The speed

(velocity) at which water can flow safely over each condition is

then a matter of test and experience.

b. The prevailing range of velocity in use for design over the

region is from three to eight feet per second. Range of permissible velocity will be determined by individual areas.

(1) A velocity of three feet per second will apply to a

poor type of sod where^ because of climate or soil^ only a

sparse cover can be expected.

(2) A velocity of four feet per second should be used under

normal conditions where the watercourse is to be established

by seeding.

(3) A velocity of five feet per second should only be used

in areas where vigorous sod is quickly obtained or where

water can be diverted out of watercourse while seeding is

being established.

(k) Velocities of six feet per second will be used only when

vegetation of good quality is already established^ or where

water can be diverted out of watercourse while seeding is

being established.

(5) Velocities of seven to eight feet per second will be

used only on established sod of excellent quality, and only

under special circumstances which cannot be handled at a

lower velocity. This condition will require special maintenance.

10.32 Shape of Watercourses

a. The parabolic cross section is best suited for general purposes because:

It is easily shaped.

Small flows are better confined to prevent meandering.

It is the most common shape found in nature.

b. The trapezoidal cross section is not a natural shape and is

limited in its application. The design chart is developed for

the parabolic section, but the same dimensions can be used for

the trapezoidal section. (See Part 10.22b.) Tendency of meandering on a wide level bottom can be reduced by using a slightly

dished section or flat "V" section (0.2 to 0.3 foot).

10.33 Watercoxorse Dimensions

Required data:

a. Watershed area, acres, soil characteristics, crops, and

259293 O - 53 - 11
10-4

topography. This information is used to estimate runoff, using

the 10-year frequency chart, Figure 3.1, page 3-2.

b. Slope (grade) of watercourse in percent. (This is the fall

per 100-foot length.)

c. Estimate of permissible velocity as listed in Part 10.31b.

d. The table of watercourse dimensions (Figure 10.1, page 10-5)

has been prepared from basic hydraulic data to eliminate timeconsuming steps and calculations by field men. You will note the

table can be used for the design of either the parabolic (saucer)

or trapezoidal cross section.

10.34 Example - Watercourse Design

a. Given:

(1) Watershed area - 20 acres

Watershed characteristics 2W = 50

(2) Slope of watercoiirse - 5^

(3) Permissible velocity - (To be seeded) Select three

feet per second.

(k) Eainfall factor R r 0.8 (determined by location)

Solution:

(1) From runoff chart, Figure 3.1

Q = 38 X 0.8 = 30.4, use 30 c.f.s. for design

(2) Enter chart (Figure 10.l) on line reading 30 c.f.s. in

left-hand column, follow to the right and under col\jmns

headed 5^ slope, reading under velocity of three feet per

second find the reading of "45/' which is width in feet. In

the same column at top under the three feet per second velocity read the depth of 0.4 feet. This results in a top width

at water surface of 45 feet and flow depth of 0.4 foot to

handle the discharge of 30 c.f.s. at velocity of three feet

per second. If site conditions require freeboard, add four

feet to width and 0.5 foot to depth. Under these conditions

it is well to consider the possibility of diverting as much

of the flow of water as possible by use of diversion(s) imtil construction and vegetation is accomplished. Also, these

conditions will require special maintenance for best results.

If, in consideration of site conditions, the above watercourse is too wide, the alternative is to use a higher velocity for design, which results in narrower width. In this

example, using a velocity of four feet per second for design.
10-5

GRASS WATERCOURSE DIMENSION CHART

Z W ZW Slope 0.5% Slope 1 1% Slope 2% Slope II 37oSippe 4% Slope 1 5% Slope 67o Slope 1 67« Slope I07P Slope |l27o Slope l47o Slope!

2 3 4 3 4 5 3 4 5 3 4 5 3 4 5 31 4 5 3 4 5 3 4 5 3 4 5 3 4 5 3 4 5

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25 19 26 13 32 16 37 19 II 44 22 12 55 28 15 67 31 16 75 36 20 100 41 24

30 23 31 16 39 19 II 45 23 13 53 26 15 66 34 16 80 36 22 90 43 25 120 49 28

35 27 II 27 13 36 18 45 22 13 52 27 r5 62 30 17 77 40 21 93 44 25 105 50 29 57 33

40 30 12 31 15 41 21 12 51 25 15 60 31 17 71 35 19 86 44 24 106 50 29 121 57 33 64 36

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23 13 58 28 16 68 35 16 80 39 22 |l00|46 27 120 56 32 64 37 75 42

50 37 14 39 19 52 26 15 65 31 16 76 39 22 89 43 25 112 52 30 62 35 71 41 62 47

60 45 16 46 22 62 31 17 78 37 22 92 46 27 107 52 30 65 36 75 42 87 49 100 56

70 52 19 33 18 54 26 15 72 36 20 91 44 25 108 53 31 126 60 35 75 43 87 50

—""

102 58 115 66

80 60 23 II 38 18 62 30 17 83 42 23 104 50 29 123 60 35 70 40 67 49 100 57 116 66 75

90 67 25 12 42 20 70 34 19 94 47 26 118 57 33 67 39 78 45 97 56 112 64 128 74 65

100 75 28 13 46 23 78 38 22 105 53 30 64 37 74 44 88 50 106 62 125

—

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120 90 33 16 55 27 94 45 26 126 61 36 76 44 90 52 105 60 125 74 67 100 113

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160 120 44 22 73 36 125 60 34 63 47 102 58 120 69 80 100 116

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72 35 119 59 •33 98 55 75 93 112 EXPLANATIONS

The first column on the left ts the runoff

in cubic feet per second. The top line across

the page shows the percent slope of the

watercourse. The second line gives a choice of

three different design velocities-3s.f. j 4s.f.

and 5s.f. The third line gives the depth in

feet at center of the watercourse and is read

under desired velocity. The figures in the

body of the chart ore top width in feet.

NOTE^

han 0.5 percent use size shown for 0.5

use diversion design chart,

ay be requested from Engineer.

260 78 38

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63 35 106 59 80 100

300 83 40 67 38 112 64 86 107

320 88 43 71 40 120 68 92 114

340 93 45 75 43 72 98

360 99 48 80 45 76 104

380 105 51 85 48 81 no

400 MO 54 89 50 86 115

420 116 56 94 53 90

440 122 59 98 55 95 For slopes less t

percent slope, or

Special designs rr

/"- . .. .

460 127 61 102 58 99

480 132 64 60

63

103

500 138 67 108

^ii-or construction aimensions add .5 to depths from chart and

/tadd 4' to widths shown in chart.

Overall construction width

2.0" Design width from chart . 2.0' >^ .1 ,

^^''^''^f'tîP»

Overall

construct

depths

-i. water surface-f 0.5' Freeboard ——-Si—^ .-^ífüR'^^ \

.^^Design <

from ch

TTSmms^iLZ. — __ ^^m^rr^' _ A

__ ^.--«BFyTA'^y'' tisiuuiisn sou- 1

zr ^"^^'^^'^^ç^^sRsTr»*. — rSSO^^^^^^ *» o* '®ast this point. 1

'"^^•^¿¡Ù^.KWJAKfr, ^ jjyrf^TTT^mff»^^^^

••«^'WWTW/rW^iT!^^ "^^

Determine size i

Given: Q-100cf.

Design velocity =

Solution: In left

slope columns a

third line from t

be 0.8 ft. — Con

EXAMPLE

}f watercourse,

s. Slope=37«

4s.f.

column under "c.f.s" find 100. Follow the 100 line right to the 3%

nd under the "4s.f." column read the top width of 53 ft. In the

he top under the 3% slope and 4s.f. you will find the depth to

struction Dimensions then ore:

Death = .8*+.5'freeboard» 1.3 feet

GRASS WATERCOURSE DIMENSION CHART

REGION NO. 3 MILWAUKEE, WIS.

U S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H.H. BENNETT,-CHIEF

-THH^ OF JI£"orifrAS?Jf wlrlk^ûîiR«

"^"^•«2^*^^ \¿¡l¡^'^j¡Z^^¿(iiu^^,c4r^

1 Revise d 2- 2'r-51 R .H.H . W dth '53 + 4 = 57 •fe<ît J

6RAWN

SEAUCHAMP

TRACED

BEAUCHAMP

CHECKED 1 DATE

KEAIRNs|9-,6-46

^ORAWING^NO.

3-L-I40I0

FIGURE lO.I GRASS WATERCOURSE DIMENSION CHART
10-6

and allowing for freeboard, the constructed and vegetated

width would be 23 + h, or 27 feet, with over-all depth of

0.5 + 0.5, or 1.0 foot.

Given:

(1) Watershed area - 30 acres

Watershed characteristics l^W = 45

(2) Slope of watercourse - 0.4^ (Use 0.5^ in Figure 10.1)

(3) Permissible velocity - 2 feet per second

(k) Rainfall Factor R = 0.7 (Determined by location)

Solution:

(1) From runoff chart, Figure 3.1, page 3-2

Q = k2 X .7 = 29.4 use 30 c.f.s..

(2) Enter chart (Figure 10.1) on the line reading 30 c.f.s,

in the left-hand coliamn, follow to the right and iinder

colimins headed 0.5^ slope, reading \mder velocity of two feet

per second, find the reading of 23 feet width, and at top

read depth of 1.0 foot. If site conditions require freeboard, add four feet to width and 0.5 foot to depth. Under

these conditions it is well to consider the possibility of

diverting as much of the flow of water as possible by use of

diversion(s) until construction and vegetation is accanplished. Also, these conditions will require special maintenance for best results.

If the above dimensions are impractical for any reason,

design will have to be at a higher velocity - say three feet

per second.

Then from chart. Figure 10.1, find on the line for 30 c.f.s.

and under three foot per second velocity, no dimension is

given. However, note the general remark which applies reading "As widths are impractical for depths shown, use first

width shown in col\imn as practical for crossing with farm

machinery; otherwise, design from Technical Note 8." Therefore, in this example dimensions will be width of 11 feet,

and depth of 1.8 feet. If site conditions require freeboard,

add four feet to width and 0.5 foot to depth. Under these

conditions it is well to consider the possibility of diverting as much of the flow of water as possible by use of diversion(s) \intil construction and vegetation is accomplished.

Also, these conditions will require special maintenance for

best results.

or
10-7

(3) Using Diversion Design Chart, Figure 9.1 (page 9-3)^

(remember a diversion is in effect a watercourse across the

slope and is on flatter grade or slope than most watercourses). Enter on the line reading 30 c.f.s. in the lefthand column, follow to the right, and under 4^-foot bottom

width and slope of O.k^ read depth of 1.5 feet. Note now

that this reading is to the right of the 2-foot-per-second

velocity line, which means that by using those dimensions

velocity will be slightly over 2 feet per second, probably

not enough to worry about. Then with design depth of 1.5

feet, allowing for freeboard, the constructed depth would be

2.0 feet. Constructed and vegetated width would be the

width of both side slopes plus the bottom width, which in

this case is 2 x 4 x 2 -H ^ or 20 feet.

If a shallower watercourse is needed for some reason, using

Figxire 9.1^ again, move farther to the right on line 30

c.f.s,, say to 10-foot bottom width, and slope of 0.^+^. Now

read depth of 1.1 feet. Velocity here is still slightly over

2 feet per second. Then with design depth of 1.1 feet,

allowing for freeboard, the constructed depth would be 1.6

feet. Constructed and vegetated width would be the width of

both side slopes plus the bottom width, which in this case

is 2 X 1.6 X U + 10 or 23 feet.

10.35 Design and Dimension Form

The examples above are illustrated on the form Figure 10.2 (pages

10-9 and 10-10), which is provided for the use of personnel in

recording the design data and construction dimensions. They are

stocked in the Regional Supply Center and are ordered by Drawing

No. 3-L-17372.

10.36 Specifications

One of the examples above is illustrated on the form Figure 10.3

(pages 10-11 and 10-12), which is provided as a job sheet for

the use of the farmer in construction and establishment of the

vegetative lining of the watercourse. One should be prepared

for each major watercourse to be constructed and vegetated. They

are stocked in the Regional Supply Center, and are ordered by

Drawing No. 3-L-23571.

lO.i^O CONSTRUCTION OF WATERCOURSES

10.^^-1 Requirements

•^a. Success of a vegetated watercourse will depend on obtaining

physical conditions favorable to growth and maintenance of the

vegetative cover. All agronomy practices that apply in establishing vegetation on a field need special emphasis when applied

to the watercourse because the sod must withstand the additional

hazard of flowing water. The determination of watercourse dimensions based on proper design will reduce this hazard to an economical minimum.

«Reference:

Agronomy Handbook and Technical Operations Plan.
10-8

b. Tile drainage of watercourses is essential where waterways

tend to be wet and in areas where tile is generally recommended.

Tile drainage may also be needed in some well-drained soils where

seepage occurs in the waterway. A well-drained waterway is essential to permit the most economical operation of the field and to

prevent damage to the waterway when crossing it with equipment.

Broken tile in waterways must be repaired. In some cases it may

be necessary to abandon old tile because of poor conditions or

because of inadequate depth. New tile should be laid immediately

following grading of the watercourse. Tile lines should be laid

to one side of the watercourse at sufficient depth so that any

laterals will have a minimum cover of 2.5 feet at the low point

in the watercourse. Tile lines should outlet at a permanent

structure or by use of corrugated pipe as illustrated by drawing

No. 3-L-1656^ in Figure 11.33. This should be provided where the

water disposal system changes from tile and broad shallow vegetated watercourse to an open drainage ditch.

c. When plans for sub-drainage are completed, actual work on

grading of the watercourse is ready to start.

10.42 Equipment

a. Many excellent watercourses have been prepared using only a

plow, disk, and harrow. These tools work best when it is possible to drive a tractor anywhere over the watercourse area without danger of overturning the tractor.

b. As the size of the watercourse increases, the greater is the

advantage of additional tools and equipment. A manure loader

may be used to advantage to slope steep banks by pushing in dirt

from the top. "When sloping is done from the top, care must be

taken to secure compaction of the loose fill material. Not more

than 8-12 inches of loose material should be allowed to accumulate before compaction can be accomplished. Then sloping can be

resumed and the process repeated \mtil completed. It is also

desirable to fill some low places and cut into banks and ridges

to improve both grade and alignment; the Fresno or roll-over

scraper and manure loader all can be used to advantage.

c. Small graders with a blade length not to exceed six feet can

be used to supplement the plow in working-in and completing the

grading. The highway auto patrol grader is excellent equipment

for all kinds of watercourse work. On large, deep, and irregular watercourses, the track tractor with bulldozer can be the

most economical type of equipment.

10.k3 Procedure

a. In extreme cases of poor and infertile soil areas, it may be

desirable first to remove the remaining topsoil and work it away

from the watercoxirse area, then grade-in the watercourse, and

later bring back the topsoil as a covering for the waterway.

This is difficult and expensive but may be necessary to establish

vegetation.
10-9

GRASS WATERWAY DESIGN AND DIMENSIONS

Jo/?/? /Foe ^56 _ ÙÏPjP/^-

CO-OPERATOR PLAN NO SOIL CONSERVATION DISTRICT

Location on form (*

XX ml'/, '/o

Drainoge Area=_6^_ Slope= Design \/= __y_ ^_ fs. Q=

ño--38 SI

_£^ VG._/_^___

30.^ SS-/^__

\2W_<#/__

^¿? c.f.s.

Location on form (* )_ ¿XÇLfnpJs CêCt I0^3j^û._

2"*^ ÖO/LLf/O/7

R-__/^___

si_-_/^_._.

vc__/^___

SS-_/^___

Drainage Area = ^^fi Slope= ^% Design V = ^^j^^^^fs.

£W_^/__

_v3¿?___ c.f.s.

Location on form K

lJfr^o/u/LO_/7 ___'_

R_-__A

X J MO-JA...

Drainage Area = _^i^___Slope=__^'.!^.7o Design \/ = .j?.t-.fs. Q=-_-?^_ _.c.f.s.

Location on formf* ^.Í>(JLf77p¿e__ __Pß_rf__ /P^34_b__

So/uf/op based 0/7 D/yersJo/7 C?7ar/'

'Ul VII

SIvc.

SS-

>N.^.^.

Drainage Area=__î?^._Slope=___^'::^_7o Design V=.__'?Zt__fs. Q=._'^^___.c.f.!

* Woterwoy numbersee land use mop

SOIL CONSERVATION SERVICE

Drowing No. 3-L-I7372

FIGURE 10.2 GRASS WATERWAY DESIGN AND DIMENSIONS
10-10

Location on formr ) ^>L<^m^/^^PjLri^^io^s^^^^ .

j^<^/^if<pjrL 4K J?/:^^ .

lo ^'"''•'^^-^ .....-.^'^"^'^

SI

VCss za'-o"

Drainage

WIUIH ! SW—f^-_.

A^ea=__^<2__Slope=i^.#__% Design V=__^t-_fs. Q=_î3p___c.f.s.

LocalMon on form (* )___ _ __

^''^/H ,/liv/" R- --

'' X

^''^''''^^'''''''-''^^

SI-_—-

VC

ss

SW-.—.

Drainage ._fs. Q= c.f.s.

" WIDiM *1

Í Areas.- Slope» % Design V=

Locolion on form (* ) _ _ _

\lliiv ,.//A'i/ R

4 ¥

DEPTH

^^^--......^^^

SI—

VC- -

ss

tfr*~ « A a

Drainage

1* WIDTH 1

1 Area= Slope= % Design V=

sw —

-.fs. Q= c.f.s.

Location on form (* ) _

i'»ff ,„ i>Vi,n \l, R__ __ __

tí

tu

^^^'^^^^•Ui^iiii./.j.iL^^

SI —

VC --_

s s -.

sw.

Drainage _..fs. Q= c.f.s.

* WIDTH •

Î Area= Slope» _.% Design V=

{REMARKS:-

The^ß ore ova}/a6/e -from ^ea/ono/Sujop/j/

Ceni^&n Orcl^r 6j/ afro^/inos /t6. ^B-L- /737^^^ee co/a/a^
10-11

SPECIFICATIONS FOR GRASS WATERWAY ESTABLISHMENTS

Jo/?r? /foe 4-S6 ¿/fûjD/'a

Cooperator Plan No. Soil Gmservation District

Waterway /^^ £xa/T?p/e Field Nn. 3BCO/7CÍ ÖO/Ut/O/7

DIMENSIONS

Width 27 Ft. Depth. JL2_ .Inches Length. 600 Ft.

Width

SOIL TREATMENT

TO BE PLOWED UNDER

Manure. / .loads per 100 ft.

Fertilizer! ^^ ^"^ ^^ analysis

Fertilizer: analysis

Fertilizer: analysis

TO BE WORKED IN THE SURFACE

^O lbs, per 100 ft.

lbs. per 100 ft.

lbs. per 100 ft.

Manure.

Mixed Fertilizer:.

.loads per 100 ft.

analysis. .lbs. per 100 ft.

Com (broadcast)..

STABILIZING CROP

Pecks per 100 ft.

SEEDING GRASS

Preparation:

«i*Pii«MN íMBíí Mi

2, Rake and remove all clippings.

3. Broadcast amnonium nitrate at.

wUm

2^- lbs. per 100 ft..

TOTAL

__^_loads

300

TOTAL

TOTAL

/S'O

.lbs.

.lbs.

.lbs.

.loads

.lbs.

.bushels

total lbs.

Seeding Mivtiiri>: S^Sro/Tfe pius soJtaó/e comjc^aAr/cr? crop

Seeding Rate of Mixture /O lbs, per 100 ft. of waterway éO total

Suggested Method of Seeding: Broadcast or drill seed August 15 to October 1. Broadcast

seed can be covered by LIQfT disking (disk set almost

straight), or a cultipacker or a rotary hoe.

SOIL CONSERVATION SERVICE

Drawing No. 3-L-23571

GPO—ses 559

FIGURE 10.3 SPECIFICATIONS FOR GRASS WATERWAY ESTABLISHMENTS
10-12

MAINTENANCE

1. Repair damaged areas promptly.

2. Mow 6 inches high and rake twice a year*

Dates

3. Apply 100 lbs. ammonium nitrate per acre

annually, preferably in early fall; and a

complete fertilizer in the spring.

4, An application of trash-free manure each year

such as chicken manure, could replace the

ammonium nitrate.

5. When plowing the field adjoining the waterway

a. Plow right angle to waterway.

b. Leave border irregular to prevent cutting

along the edge.

6, Do not use for a driveway or lane.

Note^ These ore available from the

Regional Supply Center^ see Catalog

Order by drawing No. 3-L-2357Í
10-13

b. The grading procedure for plow and grader equipment is to

drive up and down the watercourse adjacent to the low ground or

ditch and move earth into the low part. Sections not requiring

much work will be rough-finished first so that the watercourse

can be crossed with the equipment. This leaves the deeper, more

difficult areas isolated, but makes it possible to work equipment from all sides. These areas are then worked individually

until filled and rough finished.

c. Methods used in constructing terraces with a plow can also

be applied to filling a ditch. That is, essentially, to begin

plowing next to the ditch, throwing dirt into the ditch on the

first round, then plow several more rounds as in plowing a land.

This step is repeated imtil the ditch is sufficiently filled to

permit crossing. The desired cross section is then obtained by

backfurrowing at the low point and plowing lands as required.

d. When it is necessary to construct an outlet or watercourse

along a fencerow, ridge line, or across a level portion of a

bottom field, it is usually necessary to move earth out of the

proposed watercourse. For this procediire the same method as is

used for the construction of a drainage ditch can be used.

Reference is made to Part 11.

lO.i+14- Specifications

Clear trees and brush from area.

Correct drainage problem.

Construct according to design dimensions.

Secure a compacted fill free of any organic material.

Provide stabilized outlet by previously establishing watercourse, sod chutes, and permanent structures.

To establish seeding, apply mulch, increase rate of seeding,

fertilizers, and manure in accordance with specifications in

local Technical Guides. Provide protection from grasshoppers,

by poisoning.

Maintain by mowing, controlled grazing; re-establish vegetation

as necessary; and fertilize along with adjacent field.

10.50 SOD CHUTE

10.51 Definition and Use

a. A sod chute may be defined as a steep-sodded section of a

watercourse constructed to conduct the design flow of water

through it in the shortest distance at a safe velocity. The

required vegetation may be established by transplanting sod, or

if the water can be diverted around the section for sufficient

time, it may be established by seeding.
10-14

b. A sod chute may be used:

At overfalls or abrupt changes in the slope of a natural

waterway.

At the lower end of watercourses to conduct water into a

natural channel.

To conduct water from the flat area next to a drainage ditch

to the bottom of the ditch.

10.52 Limitation of Use Will Ordinarily Be Indicated in Design Tables

a. The required dimensions obtained from the chart may limit

use on the basis that required width or total length is impractical for the site xinder consideration.

10.53 Design of Sod Chutes

a. Figure 10.4 gives the design nomenclature.

FIGURE 10.4 SOD CHUTE AND TOE WALL
10-15

Basically, the consideration for design of a sod chute is the

same as for a vegetated watercourse. Since sod chutes are generally constructed by transplanting sod or protected by a diversion until seeding is established, the range in permissible

velocities is higher when compared with watercourses where vegetation is established from seed. Velocities considered safe are

given in Part 10.31b.

b. When water flows from a watercourse to a chute with a steeper

grade, a transition in flow takes place - that is, a decrease in

depth of flow with an increase in velocity. Chute widths will

usually be less than watercourse widths with a tendency toward

restriction of flow at the entrance.

c. To assure adequate entrance capacity, the sod chute table

includes required entrance depths. Levees may be constructed to

the chute entrance if necessary to provide the required depth.

10.54 Example

Given: Q = Itó c.f.s., estimated runoff from watershed.

Height to control - k feet.

Try 10^ slope of chute or 10:1. Length - i|- x 10 = kO feet.

Excellent sod availabl«; and good soil; exposure is southwest -

may be hot and dry.

Select 7 feet per second velocity.

Solution: Sod chute dimensions (Figure 10.5, page IO-I6).

In the left-hand column under "Required Capacity," find 140

c.f.s. Follow this line to the right and under column 10

percent slope and 7 feet per second velocity, find 39 foot

bottom width.

In the same column on line "Chute Depth" find 0.6 foot.

In the same column on line "Entrance Depth" find 1.2 feet.

Construction Dimensions:

Slope - 10^ or 10:1.

Height = k feet.

Length - If x 10 = ¿i-O feet plus.

Bottom width - 39 feet.

Total depth - 1.2 feet (entrance depth) +0.5 foot (freeboard)

= 1.7 feet.

Chute depth - 0.6 foot.
H

O

SOD CHUTE — DIMENSION TABLE

TRAPEZOIDAL CROSS SECTION

CHUTE SLOPE ¿ /O RATIO 00 ' 1 4% ^0^ 25-1 e%\zi\eY4^\ 8% \Zl 12-1 10% ^0^ lO-l 14% ^T^o^ 7-1

PERMISSIBLE

VELOCITY: FT/SEC. 4 5 6 7 8 4 5 6 7 8 4 5 6 7 8 4 5 6 7 8 4 5 6 7 8 4 5 6 7 8

SW2W 5W :EW REQUIRED

CAPACITY

Q. - C.F.S.

FAIR

SOD

GOOD

SOD

EXCELLENT

SOD

FAIR

SOD

GOOD

SOD

EXCELLENT

SOD

FAIR

SOD

GOOD

SOD

EXCELLENT

SOD

FAIR

SOD

GOOD

SOD

EXCELLENT

SOD

FAIR

SOD

GOOD

SOD

EXCELLENT

SOD

FAIR

SOD

GOOD

SOD

EXCELLENT

SOD

ENTRANCE DEPTH FT 0.8 I.I 1.5 1.9 2.4 0.8 I.I 1.5 1.9 2.3 0.7 1.0 1.4 1.8 2.2 0.5 07 1.0 1.3 1.6 0.5 0.7 0.9 1.2 1.5 0.4 0.5 0.8 1.0 1.2

CHUTE DEPTH FT 0.6 0.8 1.0 1.2 1.4 0.5 0.7 0.9 I.I 1.3 0.4 0.6 0.8 1.0 1.2 0.3 0.4 0.5 0.7 0.9 0.2 0.3 0.4 0.6 0.7 0.2 0.3 0.3 0.4 0.5

AC!RES

10 10 12 15 10

15 10 14 18 10 12

20 10 14 19 10 24 12 32 16 10

25 12 18 24 12 30 15 40 20 13

30 15 22 10 30 15 36 19 10 49 25 16 10

35 ,. 18 27 12 35 18 10 42 22 12 29 19 1 1

40 10 21 31 15 40 22 12 48 26 14 34 22 13

45 12 25 10 36 17 45 25 14 54 30 17 10 38 25 15

50 14 29 12 40 20 10 50 28 16 33 19 11 42 27 17 10

60 18 34 16 48 25 12 60 34 19 10 40 24 14 10 47 33 21 13

70 21 10 40 20 10 57 29 15 40 23 13 47 28 17 39 25 16

80 25 II 46 23 1 1 34 18 10 46 27 16 53 33 20 3 45 29 19

90 29 13 53 27 13 39 21 II 53 31 18 10 37 24 5 33 22

100 33 15 59 31 15 44 25 13 59 35 21 13 42 27 3 37 25

120 40 19 10 38 20 10 54 31 17 10 43 26 17 51 33 22 45 31

140 48 24 t 1 45 25 12 37 21 1 1 50 32 21 39 26 37

160 55 28 14 52 29 16 43 26 14 59 37 25 46 30 42

180 33 16 60 34 19 10 49 30 17 42 28 52 34 48

200 37 19 39 22 1 1 56 34 20 48 32 38

220 41 22 10 43 25 14 38 23 36 43

240 45 25 12 48 29 16 42 26 40 48

2 60 50 27 14 52 32 18 47 29 43 52

280 54 30 16 56 35 20 51 32 47

300 58 33 18 10 61 38 23 55 35

EXAMPLE SOLUTION CONSTRUCTION DIMENSIONS

Biven- Q = 90c.f.s. Estimated runoff from woterstied. In the left hand column under "REQUIRED CAPACITY" Slopes 8% or 12 = 1 slope.

Height to control - 2.5 feet. '^•^•"- *'"f "^°" *=•*•"• ''°";*. '^'^ ^° ''^^^ °"^ """^^^ Bo'to'" «¡^^h = 31 feet.

^ ««, , ^ column "8%" slope and "6" ft. per second velocity Total depth = 1.0' (entronce depth) +0 4' Try 8% slope of chute or 12= k Chute length = , „,... , ^ ' *^ ' wiironce oepm/ -r u.t

2.5 X 12 = 30 ft. (length is O.K. for site) ?"'' ^' *"' ''°"°'" *"^*'- '" ^'""* '=*""'"" °" ""« (freeboard) - 1.4 feet.

Good sod available and good soil' CHUTE DEPTH' find "0.5" foot. In some column Chute depth = 0.5 feet. (Normal excavation

SOD CHUTE - DIMENSION TABLE

TRAPEZOIDAL CROSS SECTION

Sel ect velocity = 6 feet per second.

CHUTE DEPTH ^

on line

FREE

ENTRANCE DEPTH find 1.0 foot.

BOARD 0.3 TO 0.5 FT TOTAL DEPTH

^-^^^ENTRANCE DEPTH ^^

and shaping will provide required depth

plus additional depth for freeboard.)

NOTE= Minimum bottom width 10 feet.

BASIS OF DESIGN

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. M. BENNETT. DIRECTO«

REGION: 3 R.H.MUSSER. DIRECTOR Ja^'^^'^^^^^i^^^^^^^T'" rt^œ^^^^^m^'' REFERENCE:

CHULTE ENTRANCE V=-LM6_R2/3SI/2 n = .040

CARTOGRAPHIC APPROVAL TECHNICAL APPROVAL

41 SIDE SLOPES

DESIGNED

r. R. Wire

DRAWN

C. Yurk

MEW.

«HECKEO DATE DRAWING NUMBER

B ?, s, 3-L-16240 B-ZI-SI SHEET OF
10-17

10.56 Construction of Sod Chutes

a. Sod chutes may he subjected to relatively high velocities;

it is recognized that the maintenance of vegetation is somewhat

difficult and hazardous. Particular care must be taken in

design, layout, and construction.

b. If a dumpy level is available, it should be used to set final

grade stakes before laying the sod or seeding. The chute should

be level across the width, on a line at a right angle with the

direction of flow. (Grade stakes will assure a level cross section and a uniform grade.) Construction of level cross section

can be made with carpenter's level, tape, and straight edge.

c. To determine a satisfactory location to end a watercourse,

or a sod chute presents many varied and difficult problems. The

objective is to terminate a location so that the watercourse

below is stable. The most common problem is that the channel

below the chute is narrow. Another problem is that conditions

at the bottom may not be favorable to establish and maintain

vegetation because of poor soil or rocky condition or siltation

from adjacent ditches or streams.

d. All of the stated problems are commonly corrected by use of

a notch spillway dam or a toé wall (Figures 10.6 and 10.7, page

10-18). All the necessary information set up in Part 7 should

be followed in designing this type of structure.

e. The same specifications for construction of a watercourse

apply to the construction of a sod chute as set up in Part

lOM.

f. In addition to the above specifications, the following apply

if chute is to be sodded:

Finish final grade with not less than three inches of topsoil.

Leave surface in a condition similar to a firm seedbed.

Cut sod thin.

Lay sod in strips across the chute.

Start laying sod at the bottom.

Stagger Joints of the sod strips.

Lay sod two feet up side slopes.

Fill any open joints with loose soil.

Tamp or roll all laid sod.

Eubber-tired farm tractor is a good roller.

Sod should be pinned down in some manner. Wire (No. 9)

staples, or chicken wire pegged down, are some successful

metiiods used in the field.
10-18

H^-^ô' 1

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4'{rYp^¿^/&'\ ^4" 1 ryp<,^&>/<s'yí

*\s 1 ¡

H

1 kl—^a -

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:

-g1 1

<f rvi?<TZ(^./ß'

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^gr-.vráy-'-',

ELEVATION

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rr/xf ^ <g /g"

r^fitr ¿ 
 /a'

SECTION ON t

BAR TYPES

A/o/e : fbr /argier

s/nucfures Sea f/^. 7JO

O^^.A/o. 3'¿- ZZÖ33

M^ ^S

^

jy- <g'

TYPE - I

Z -O

PLAN

WIDTH OF CHUTE (W) 8'-0" 10'-8" 13'-4* 16'-0' 18'-8* 21'-4" 24'-0f' 26'-8" 29'-4" 32'-0" 34'-8" 37'-4" 40*-0" 42'-8" 46'-4" 48'-0"

NO. OF TYPE 1 BAR 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4 4

NO. OF TYPE 2 BAR 12 16 20 24 28 32 36 40 44 48 52 56 60 64 68 72

STEEL (LBS.) 26 35 44 53 62 71 80 89 98 107 116 125 134 143 152 161

CONCRETE (CUYOS) 1.25 1.50 1.75 2.0 2.25 2.50 2.75 3.0 3.25 3.50 3.75 4.0 4.25 4.50 4.75 5.0

MORTAR (CU.YDS.) 0.29 0.32 0.35 0.38 0.41 0.44 0.47 0.50 0.53 0.56 0.59 0.62 0.65 0.68 0.71 0.74

STRETCHER BLOCKS 35 39 43 47 51 55 59 63 67 71 75 79 83 87 91 95

TYPE - 2

Afa/ar/a/A/o/eS'

/.//7 <7</i////o/T /<? ^/r<f/c/>&r />/ocÁs ^

cor/?ar /*' <S" /fa//"ó/ocA:s <7re mço//-<i<:/.

Z. M^A^/-e rtTcri/Zrift/ /ffrrç/A o/ /-ype -

/ Á<7r /s/7o/ <Ty<y//cró/ej/iii'a orA^rife s/?//c'^i/

^crr-s /T7<7/- ^¿//fjf///¿//<r</ /^/^ o//S'/:s-

/e/7p//? ec¿/a'///7c Ai^-^.'

Coy7j-/rc/c//<y^ A/ö/tPS"-

/. ////yo/^/s /o ¿>í? ^.

^. /V/'S-/ croc/rife di/cyc/r^ ^/fc7//à^ /<7/c/

¿'//7 /res/?/y/oo/yree/ eTc?/7e:re/e.

J. Afoy/í/r sy^<7//¿e /yoc/^//?or//¿7/:fc/

ce/77e/?//a J/far/s /ar/>e</a ^<7/7¿/.

4. /^// erore à/oc/s ^/fc////fe ////ec/ M^///

/r?or/ar c7/j</ //>orotjç^/y /a/77p«Tc/. .,

^ /r//^/^<T/s/?a7/¿)6^ A/o.^ or ^ jí^rs.

FIGURE 10.6 STANDARD DESIGN-CONCRETE BLOCK TOE WALL

^'-O " iV 4-o .1

»a . . ^ a", rx,iy^ 9 is/^' \<z\<s'\ ryoa j @/^'\&'

i

i

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.

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a' 4-/yx>e'/e/^' ^' ó' rv/>eJ & /jZ' a' <s' ry/>e J & /^' tf' «^^ 4-/rpe-/e/r i?:

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ELEVATION SECTION ON t

a' TvßeJ iS Z^" a <gr' ry^ js/-?' <í'

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^

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^'-o" ê^ 4'-o' """"

BAR TYPES

cI¿1

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PLAN

MATERIALS SCHEDULE

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7:^e /o/a/s/?//ee£//e^ff//f ^/7<7// e^</a/

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WIDTH (W) (FT) 8 «0 12 14 16 18 20 22 24 26 28 30 32 34

76

36 38 40 42 44 46 48

104

50

NO. OF TYPE 3 BARS 24 28 32 36 40 44 46 52 56 60 64 68 72 80 84 88 92 96 100 108

STEEL (LBS) 57 64 71 78 86 93 100 107 115 122 129 136 144 151 166 175 183 190 197 204 212 219

CONCRETE (CU. YDS.] ».5 1.7 L9 ZA 2.3 2.5 2.7 2.9 3.1 3.3 3.5 3.7 3.9 4.1 4.3 4.5 4.7 4.9 5.1 5.3 5.5 5.7

£ee/? /oe »ya// M^/// re^iy/ro' /^ Ziu>e - / óer/s, S - 4 /o/7p,jyy7</ ^/j</>e - £ /KTZ-S; M^-ß /o^?^

^ct^Ar /^0 '/-O

FIGURE 10.7 STANDARD DESIGN-REINFORCED CONCRETE TOE WALL
10-19

Protect frcÄn livestock during critical seasons .

Mowing or grazing is a necessity for maintenance.

g. A suggested type of sod cutter is illustrated. (Farmers*

Bull. I8l4)

Cutting blade

of Mê'X 3" too/ st9ef

e/mctric we/ded. Thg

mrttirm cutting 0dge

of b/9de to be sñsrpmned.

f'M /€' bo/ts

with W09hmrs

S/oreQc/er of/yt/pe SVa^f

-/Z'- -/-Z"- -w

sfot bar for oeOastah/e

Depth

Z'x8''xS' for floor-^

^ Z'xf'jf/Z' Jpreoofer

y0r^S/opeWf»fw^

ÉÎT ^ Z-Xi'A C O' Af9//^e Oê^

FIGURE lOB A HOME-MADE SLED'TYPE SOD CUTTER

259293 O - 53 - 12
11-1

PAET 11

LAND DRAINAGE

11.10 INTEODUCTION

11.11 Purpose and Scope

The information on land drainage in this handbook is written as

a field guide for farm conservation planners and conservation

aids. It is intended for their use in the solution of relatively simple drainage problems on small areas of agricultural land.

No attempt has been made to cover the entire field of land

drainage as it applies to the larger^ more complicated problems.

11.20 EFFECTS AND BENEFITS OF LAND DRAINAGE

11.21 Drainage Defined

Drainage is the removal of surplus water, known as free water or

gravitational water, from the surface or below the surface of

farm land in order to create favorable soil conditions for plant

growth. The process of removing free water from the surface is

referred to as surface drainage and the removal of free water

from the subsoil is known as subsurface drainage. Sometimes

free water in the soil is called internal water and the process

of removal is termed internal drainage.

11.22 Kinds of Water in the Soil

a. Hygroscopic moisture is the thin film of moisture retained

by each soil particle after it has been air dried; or, in other

words, it is the moisture that is absorbed by the soil particles

from the atmosphere. The hygroscopic moisture film is extremely

thin and it is held so firmly by adhesion to the soil particles

that it cannot be used by the roots of plants. There is no movement of hygroscopic water from one soil particle to another.

Figure 11.1, page 11-2.

b. Capillary Water

(1) When a soil has the maximum amount of hygroscopic water

and additional small amounts of moisture are added, the

thickness of the moisture fiLn is increased. When a continuous film of water develops between soil particles it is

known as capillary water. Figure 11.1. Small amounts of

capillary water are not available for plant growth. The

moisture content must be above the maximum hydroscopic

level, a certain percentage (this varies with the soil),

before there is sufficient moisture to prevent a plant from

wilting or dying. This percentage of moisture is called the

wilting coefficient.
11-2

hygroscopic water

IATTTTW^ yf//\ I/////I\

air space for

.... . . ^^iiiiiij ^iiM^^^^, soil particles gravitational water __^__jv(mv7\^^

capillary water

FIGURE I LI SOIL WATER IN RELATION TO SOIL PARTICLES

(2) As capillary water is added to the soil above the wilting point the soil moisture film aroimd the soil particles

increases and a portion of the pore space between the particles becomes filled with water. This is the water upon which

the roots of plants mainly rely for plant growth.

(3) Capillary water is controlled by surface tension and

the movement may be up or down. Capillary "pull" depends

on the curvature of the moisture film around the soil particles; the smaller the radius of curvature the greater the

pull. Thus capillaiy pull is greater in soils having small

particles such as clay; and less on soils with relatively

large particles such as sandy soils. As more and more water

is added to a soil the moisture film around the soil particles becomes thicker and presently the point of maximum

capillary capacity (moisture-holding capacity) is reached.

^- Free Water. If water is added above the capillary capacity

it will slide off the moisture film and be acted upon by gravity.

This water is called free water or gravitational water. See

Figure 11.1. Sometimes free water below the surface is referred

to as internal water. The presence of free water in the soil or

on the ground surface for any period of time is detrimental to

plant growth and this is the water that needs to be removed by

drainage.

11.23 Benefits of Land Drainage

a. Eemoval of free water promotes soil bacterial action.

(1) Soil bacterial action is essential for the manufacture

of plant food. Free water in the soil creates unfavorable

conditions for plant growth because the pore space is filled
11-3

with water and air is excluded. The presence of air in the

soil is essential for soil bacteria growth. These bacteria

change organic matter into organic acids which in turn dissolve the elements in the soil that furnish plant food.

After the elements of plant food have been changed into soluble salts through bacterial action they are taken into the

capillary water and held in readiness for use by the plants.

(2) The roots of plants and the soil bacteria must have

oxygen. Drainage accomplishes this by providing air space

in the soil. Changes in atmospheric pressure assist in

"ventilating" the soil. Also, through rainfall, water

passes downward in the soil, carrying out carbon dioxide and

permitting fresh air to be drawn in. Thus drainage provides

soil aeration.

b. Drained soils warm up more quickly.

(1) Soils that are too wet warm up very slowly. They are

frequently referred to as cold soils. The removal of free

water by drainage allows the soil to warm up more quickly

because considerably more heat is required to raise the temperature of saturated soil as compared to well drained soil.

(2) Soil warmth promotes increased activity of bacteria.

This in turn affects the rate of release of plant food and

the growth of plants.

(3) Soils that warm up sooner in the spring can be planted

to crops earlier and better germination conditions for seed

are provided. These factors result in a longer growing

season.

c. Drainage increases the root zone area.

(1) The removal of free water in the subsurface increases

the amount of capillary moisture available to the plant.

For example, if the free water is removed only from the top

foot of soil the roots will be confined to this area for

obtaining plant nutrients; but if the free water is removed

from the top three or four feet this entire depth of soil

is available as a root zone upon which plant nutrients and

moisture can be obtained. Figure 11.2, page 11-4,

d. Most soils cannot be over-drained.

The removal of free water in the soil simply removes moisture in

excess of the maximum capillary capacity. Drainage does not

remove the capillary water and there is no danger of overdraining a soil by placing the drains too close together. The

depth of the drains does control the height of the water table

however, and if the water table is too low in soils with a low

capillary "pull" the moisture may not move upward into the root

•zone. On most soils there is no danger of over-drainage, but on
11-4

UNORAINED LAND TILE DRAINED LAND

ROOT GROWTH IS RESTRICTED TO THE SOIL AREA ABOVE THE

"PERCHED" WATER TABLE, WHEN WATER RECEDES AFTER ALONG

WET SPELL, ROOT EXTENSION IS USUALLY LIMITED.

Taken from "Form Orainoge-An Importont Conservotion Proctice," by R W. Monson and

C. 0. Rosf, Agricultural Engineering, June 1951.

FIGURE 11.2 ROOT DEVELOPMENT OF PLANTS GROWN ON DRAINED AND UNORAINED SOILS

some extremely sandy soils and some peat and muck areas there

is this possibility. On these soils there is a depth of water

table which is best for plant growth and in the design of the

drainage systems it is necessary to take this into consideration.

11.2^ General Conditions Under Which Drainage is Applicable

Not all land can be drained economically^ and it is well to keep

in mind that there are limitations. The general conditions

under which land drainage is applicable are the following:

a. Capability of the Land

The soils to be drained should be of such capability as to provide good permanent cropland or pasture after drainage.

b. Availability of Outlet

The land to be drained must have an adequate outlet that will

provide sufficiently rapid removal of drainage waters.

c. Degree of Drainage Required

Drainage must be planned to provide the degree of drainage

required by the crops to be grown.

d. Protection From Overflow

Lands subjected to frequent or prolonged overflow from streams

must be protected by levees and floodgates or pumps before the

drainage operation is undertaken.
11-5

11.30 PEELMINAEY IJWESTIGATION OF DRAINAGE JOBS

11.31 General

a. When the drainage of any tract of land is contemplated^

whether by open ditches or tile drains^ a certain amount of preliminary investigation is necessary in order to get a clear

understanding of the nature of the problem^ the amount of work

that will be required^ the approximate costs, and the benefits

that will accrue. This is true whatever may be the size of the

tract to be drained, but the larger the area the more time

should be given to preliminary work. The conducting of a preliminary analysis may be divided into the following steps:

(1) Reconnaissance of the area.

(2) Assembling maps and other pre-field data.

(3) Preliminary instrument work.

(k) Preliminary design, cost estimate, and appraisal of

benefits of the proposed job. ,

On small jobs these steps may be accomplished at one time; but

on larger jobs the steps generally are more or less separate

operations. These are discussed in the following paragraphs.

11.32 Reconnaissance of the Area

a. Importance and General Nature of Reconnaissance

(1) The first step in the preliminary analysis of any drainage project, whether large or small, is a reconnaissance of

the area. This is of very great importance and it should

never be omitted, for it is the beginning step in sizing up

the job.

The reconnaissance is sometimes called 'Valking the area,"

for there is no substitute for thoroughly tramping over

literally every acre to become acquainted with the problems,

the general topographic conditions, and any unusual physical

features.

(2) For the reconnaissance a map of the area is very helpful for reference purposes. The only instriioaent needed is

a hand level and a soil auger for making soil borings if

drainage of the soils is questionable. Never attempt to

make a preliminary instrimient survey of the area -until it

has first been examined by a reconnaissance.

(3) In this initial step available information from the

landowner and others familiar with the area should be

obtained. The technician should not attempt to give a solution to the problem but rather to seek information, and
11-6

make sufficient observations to ascertain the over-all

feasibility of the job as indicated by the nature of the

soils, the probable location of the outlet, the approximate

area to be drained, and the general lay of the land. In

short, the technician should acquire a mental picture of the

problem and formulate his plan for gathering additional preliminary survey data and information needed to make an

appraisal of the practicability and feasibility of the job.

b. Nature of the Soil

(1) The first thing that should be considered, both by the

technician and the owner, is the inherent fertility of the

land. Not all land that can be drained is worth the cost.

The economic justification of the job will depend largely

upon the value of the crops that can be grown on the drained

land. Some wet land can be drained easily but the soil has

definite plant food deficiencies; other soils of heavy clay

are difficult and expensive to drain; still other soils have

subsoil conditions that practically preclude the construction

of drainage works. The soils should be carefully investigated both from the standpoint of physical feasibility of

accomplishing drainage as well as the productiveness of the

land. These factors should be carefully and thoroughly explored by the technicians in consultation with property

owners and others who have had experience in draining similar land. Before proceeding further with the investigation

a favorable decision should have been reached that the land

can be drained and that the benefits derived are likely to

justify the cost.

(2) In conducting the soils investigation all sources of

information should be utilized. Where there are conservation surveys, these should be referred to, and if the nature

of the soils make drainage doubtful an individual trained in

soils should be consulted. Sufficient borings should be

made with the soil auger to indicate whether or not drainage

can be accomplished, and if there are physical soil conditions that need more careful exploration.

11.33 Assembling Maps and Other Pre-field Data

If the reconnaissance indicates the proposed job is feasible,

steps should be taken to make more thorough preliminary observations. The technician will save considerable time if he

assembles as much data as possible in the office prior to returning to the job. First and of foremost importance is a suitable

map of the area. For small jobs this generally will be aerial

photos, and conservation survey maps. For larger jobs, county

or township maps may prove helpful. But in every case locate

the best map available. An office study often will indicate

physical features of the job that should be explored, and from

information obtained in the reconnaissance it may be possible to

delineate the benefited area and the watershed boundary. The
11-7

conservation survey map should be studied and the technician

should familiarize himself with the soils of the area, particularly as they relate to the drainage problem.

11.3¿í- Preliminary Instrument S\irvey

a. The nature of the drainage problem may be such that a

reconnaissance is all that is needed to arrive at a preliminary

determination of the feasibility and practicability of the job.

This is more likely to be the case in small projects or where

land drainage patterns are so pronounced that the physical lay

of the land is obvious. But frequently some preliminary instrument work is needed in order to determine if the job can be done

and the approximate cost.

b. Regardless of the size of the job, or the nature of the

drainage problem, the first thing to establish is the location

of the outlet and carefully investigate its adequacy. This may

have been done approximately in the reconnaissance but it should

now be more definitely determined. Such level readings should

be taken and other measurements and estimates made to enable the

technicians to reach a decision regarding the outlet because the

functioning of the whole drainage system hinges on this point.

c. Preliminary Instrument Siirvey

The nature of the problem as well as the lay of the land will

determine the amount of preliminary level shots that will be

necessary. Some technicians gather such meager data that it is

impossible to reach a preliminary decision on the Job. Others

gather so much detail that it virtually amounts to a detailed

survey. The objective of the preliminary instrument survey is

to obtain elevations, topography, and other field information

necessary to definitely determine if the Job is feasible, what

it will cost, and the probable benefits. Only that field information should be gathered that is needed to determine these

points. Some detailed suggestions for making preliminary level

surveys follow:

(1) Establishing Bench Marks

Begin the preliminary level work by establishing a bench

mark conveniently located, and as the survey progresses

establish still other bench marks. If properly located and

permanently established, these bench marks will be very

helpful and time saving if a more detailed survey is made

later.

(2) Preliminary Topographic Information

The purpose of preliminary topographic siirvey data is to

determine the general lay of the land so that the approximate pattern of the drainage system can be tentatively

planned. These topographic shots can be plotted on a small
11-8

sketch in the stirvey book, or they can be located approximately on an aerial photograph. Only critical points in

topography should be taken, keeping in mind that the object

is merely to ascertain the general plan of the drainage system.

(3) Preliminary Profiles

Preliminary profiles of existing or proposed ditch lines and

tile mains frequently are necessary in order to establish

the amount of grade available, estimate approximate yardage

of earth that must be excavated, etc. The method of running

preliminary profiles is similar to that used in detailed surveys described in Part 1, except that the readings are taken

a greater distance apart and stations are not marked by

stakes except at intervals of 500 to 1,000 feet. Distances

along the profile can be determined by rough chain measurements, by means of stadia, or by accurate pacing. If an

aerial photo of known scale is available the location of

readings can be indicated on the photo and the distances

scaled later in the office. Sufficient elevations of average

gro\md, low spots, flow line, and cross section readings

should be taken so that a preliminary profile can be plotted.

This is necessary in order to determine the grade available,

depth of channel or tile, and approximate yardage to be

excavated from open ditches. The same accuracy should be

exercised in obtaining preliminary profile elevations as in

the final survey, the main difference being the frequency of

the shots and a minimum of stationing along the profile.

11.35 Other Preliminary Field Information

At the time of the preliminary instrument survey, other pertinent

field data should be gathered. This information, if accurately

obtained, may be used later in final design.

a. Soils information should have been determined during the

reconnaissance but if some doubt exists regarding the soils

these points should be cleared up at this time.

b. The area in need of drainage should be delineated on an

aerial photograph.

c. The drainage area should also be outlined if it is a factor

that will affect design of the system.

d. Size and elevation of culverts, bridges, and other physical

features affecting preliminary design should be obtained.

e. Information regarding crops to be grown by the owner should

be gathered, since this may affect the proposed design.
11-9

11.36 Preliminary Design, Cost Estimate, and Appraisal of Benefits

With the preliminary levels and other field information, a preliminary plan of the drainage system should be prepared. For

simple small jobs this preliminary plan may be very simple

(possibly nothing more than a sketch in a note book) , but on

larger jobs it may be necessary to plot up profiles, ditch cross

sections, and topographic information to arrive at the preliminary design. This preliminary design is important because it is

the final basis for determining the feasibility of the Job, the

approximate cost, and the probable benefits. Therefore the preliminary design needs to be done with a reasonable degree of

accuracy, particularly as it affects these points.

11.37 Discussion of Proposed Plan With the Owner

The final step in the preliminary investigation is to present the

findings to the owner. All facts, both favorable and unfavorable, should be discussed; the general plan, together with the

estimated cost and the benefits that will be likely to result,

should be explained. With all of this information the owner can

intelligently reach a decision on whether he desires to proceed

with the job. If the owner*s decision is negative a large amount

of time will not have been spent on xinnecessary surveys and

detailed designs. If he desires to proceed, then the preliminaiy

information will be most helpful and time saving in making the

detailed survey and final design of the job.

11.1^0 DEAINAGE OUTLETS

11.kl General

A drainage outlet receives the water from an individual field

drainage system or from a series of field drainage systems. The

importance and necessity of an adequate drainage outlet is

obvious for there must be some method of disposal of field drainage water if the system is to function. An adequate outlet will

remove the surplus water from the area drained before damage

occurs to the crops.

11.42 Kinds of Drainage Outlets

a. There are four kinds of drainage outlets:

(1) Open ditch outlets

(2) Tile outlets

(3) Combination tile outlet and relief ditches

(k) Outlets by drainage pumping.
11-10

b. Open Ditch Outlets

(1) An open ditch outlet is an excavated open channel constructed to a predetermined size and grade for the purpose

of disposing of drainage water from surface, or tile drainage system, or for disposal of flood water. Open ditch outlets vary in size from small individual lateral ditches to

main outlet ditches.

(2) Open ditch outlets are commonly used because they are

comparatively low in cost and soirface water is rapidly and

efficiently removed. However, they have some disadvantages.

Open ditches occupy land area, make farming operations more

difficult, the construction of bridges is necessary, regular

cutting of vegetative growth, and clean-out at periodic intervals is required. Under certain conditions therefore, as

described under tile outlets, this latter method may prove to

be more satisfactory.

c. Tile Outlets

(1) A tile outlet is a covered drain of predetermined size

laid beneath the ground surface at a specified grade and

elevation. It generally serves for the disposal of water

from tile drainage systems, but it may also be used to

remove surface water from shallow depressional areas.

(2) Advantages to the uses of tile outlets are; low

maintenance cost, no land area is taken up by the outlet,

and no bridges or culverts are required. In the past, when

installation costs were lower, there was a tendency to use

large size tile outlets (up to k2 inches in diameter). But

the present trend is toward the use of more open ditch outlets .

(3) The choice between open ditch and tile outlets is

largely a matter of economics. Where land values are high,

tile outlets may prove more practical than open ditches for

the smaller drainage areas (under 300 acres). Generally an

open ditch outlet is cheaper to construct and maintain than

a tile outlet where the diameter of the tile exceeds 2k

inches.

{k) Tile outlets do not, in many cases, eliminate damage by

excessive flood waters. This runoff flows over the groTind

surface, creating a ditch or gully frequently washing out

the tile. In many cases a surface relief ditch may be

necessary,

(5) The design of tile outlets should be made by an engineer. Farm conservation planners, however, need to be sufficiently conversant with the general conditions under which

this type of outlet is applicable.
11-11

d. Combination Tile Outlets and Siirface Eelief Ditches

(1) Where tile outlets are used in preference to open

ditches and the capacity of the tile is not sufficient to

remove storm waters, a surface relief ditch should be provided. They may be vegetated or bare channel, depending

upon the channel velocities. The use of surface relief

ditches to relieve flood waters may result in a more economic design for the tile outlet, since the tile would not be

called upon to carry storm flow.

(2) The design of combined tile outlets and surface relief

ditches will not be discussed in this handbook. The complexity of the problem generally is beyond the scope of

drainage work xmdertaken by farm conservation planners and

their aids.

e. Outlets by Drainage Pumping

(1) Where an outlet is not available to receive gravity flow

from drainage systems the water may be discharged into

natural streams or outlet ditches by p\amping. This type of

outlet is mainly applicable to large levee districts along

main tributaries. However, drainage pxmips can be used

successfully as a means of outletting drainage water from

relatively small individual field installations. This type

of outlet has been especially successful in the drainage of

peat and muck soils for truck crops, and it has also been

used successfully as a means of outletting tile drainage

water for regular field crops. Limiting factors that affect

the installation of field drainage pumping systems are the

initial installation costs, fixed pumping charges, and annual

maintenance costs.

(2) The use of drainage pumping systems has limited application and the design should be done under the supervision of

an engineer. Consequently this type of outlet is not discussed further in this handbook.

11.50 OPEN OUTLET DITCHES

11.51 General

a. Open outlet ditches are the only kind generally applicable

to simple installations by farm conservation planners and aids.

The following discussion, therefore, is limited to this type.

b. In design and construction of drainage outlets the steps or

procedures generally used are the following:

(1) Obtaining necessary information and surveys.

(2) Plotting siirvey data and compiling the infonaation on

an appropriate data sheet.

(3) Design of the outlet ditch.

(k) Layout and construction.
11-12

11.52 Obtaining Necessary Information and Surveys

a. Profile Infonnation

The obtaining of various elevations and other physical information along the course of the ditch and in the adjacent

fields is referred to as profile information. Slightly

different procedures and information are required where there

is an existing ditch and where a new ditch is to be constructed. The information to be obtained in each case

follows :

(1) Profiles where there is an existing ditch,

(a) At even 100 foot stations or at critical points

between stations obtain elevations of the natural field

level alongside the ditch, the old ditch bottoms, and

the top of old spoil banks.

(b) On existing culverts and bridges along the ditch

line obtain the following: location, size of opening,

length, and kind of material (concrete, C.M.P., etc.).

Also secure upstream and downstream elevation of the

flow line, elevations of top of road crossing the

structure, and the elevations of low points on the road

in the vicinity.

(c) Where existing tile outlets empty into the ditch,

obtain the location, size, and kind of outlet, and the

elevation of the flow line.

(d) Where open ditches, laterals, or tributaries drain

into the ditch, obtain the bottom elevation of the flow

line at the point of entrance and any other pertinent

data that would be useful in design.

(e) Locate, describe, and obtain elevations as required

of any other physical features along the ditch that will

affect the design such as: cattle ramps, fences, surface flow entering ditch, etc.

(2) Profiles on new ditch lines.

If a new ditch is to be constructed the centerline of the

proposed ditch must be located first, then obtain the following:

(a) Natural ground elevation along the centerline of

proposed ditch at even stations and at critical points

between even stations. Obtain similar elevations of the

natural ground alongside the ditch also if there is any

appreciable variation.

(b) Information and elevations on culverts, bridges,
11-13

and roads, and other features along the ditch line as

specified for profiles along existing ditches.

(c) The location, size, and flow line elevation of

existing tile that will be intersected by the ditch.

b. Cross Sections

(1) On existing ditches take cross sections at intervals of

100 to ^00 feet, depending on the irregularity of the topography and variation in the size of the ditch. These cross

sections should extend out into the land adjoining the ditch

so that any low points needing drainage will be picked up.

(2) Where there is no existing ditch, cross sections generally are not needed unless the ground level on either side

of the ditch line is obviously at a different elevation.

c. Side Shots

If there is any evidence whatsoever of low points in the field

to be drained, elevations of these low points should be obtained.

Sometimes this can be done in connection with obtaining profiles

or cross sections, but if this is not possible a line of levels

should be run to the low point to obtain the elevation. The

location of this point should be obtained and described in the

field notes.

d. Soil Borings

Take as many borings as are needed to be sure of the kind of soil

material to be encountered in the proposed ditch construction.

e. Watershed Information

Locate the watershed boundaries on a suitable map, preferably an

aerial photo. Generally this can be done with the aid of a hand

level or by observation of the direction of waterflow. Farmer

information also is helpful.

f. High Water Marks

Obtain elevation and information of high water marks and flooding in previous years. Sometimes drift marks of previous high

water is noticeable on trees, culverts, or posts. Often the only

source of high water information is from the local people residing near the ditch. High water elevations should be obtained

at 500 to 1,000 foot intervals along the ditch under design and

the height of flow of the channel into which the ditch outlets

should be definitely obtained.
11-14

11.53 Plotting Survey Data

The procedures and methods for plotting survey data described in

Part 2 "Preparation of Engineering Data Sheets/' should be followed. A sample open ditch data sheet is shown in Figure 11.3,

page 11-15.

II.5Í1. Designing the Outlet Ditch

Factors affecting the size of the ditch are the drainage runoff,

required depth, grade of the ditch, the ditch side slopes, culverts, and other structures.

a. Determining Drainage Rimoff

(1) Open drainage ditches generally are not designed to

carry peak runoff resulting from a particular frequency

rain. Ordinary field crop ditches are designed to remove

excess surface water within a 24-hour period following an

ordinary rain. Some surface flooding of the land during

this period is permissible.

(2) Specialized crops such as truck crops, however, require

design and construction of a ditch of such a size that overflow seldom results. For these crops, flooding cannot be

permitted during the growing season except for two to four

hours. The high crop value warrants this added drainage

protection; and furthermore, most specialized crops such as

carrots and onions are extremely sensitive to flooding.

(3) Drainage runoff is determined on the basis of the

removal of a definite nxamber of inches of rainfall over the

entire drainage area in a 24-hour period. Design curves for

the removal of various depth of water in 2k hours are given

in Figure 11.4, page 11-I6. Determine the drainage runoff

to be used in open ditch design from these curves as follows:

First determine the watershed area from the watershed map;

then, select the curve on Figure 11,4 that is applicable to

the condition and particular location and read the drainage

runoff "total discharge" from that curve for the watershed

area.

b. Depth of Ditch

Two factors affect the depth of outlet ditches; the depth required

to remove surface runoff and the depth necessary to provide an

outlet for tile drainage. Ditches should be checked for both of

these factors to determine which one governs depth.

(1) Depth required to remove surface runoff.

In order for the surface water to flow into ditches freely

the design ditch flow line should be below the ground surface.

This is accomplished by giving ditches extra depth varying
3c

:x3>

-Drmo>>OmoXo>

{/i X

IH

VJl
11-16

DRAINAGE RUN-OFF CURVES FOR OPEN DITCH DESIGN

IN FLAT WATERSHED AREAS OF LESS THAN 2 SQUARE MILES

100 200 300 400 500 600 700 800 900 1000 1100 1200 1300

Watershed Area In Acres

Notes f Curves applicable only to flat watershed areas having average slope less thon 25 feet per mile watershed area to be determined above each

section of ditch for which capacity is to be computed.

For lands with steeper slopes than given oDove and ordinary valley drainage use next hiaher run-off curve to give equal protection.

Explanation of CurvesT B - For excellent droinoge except in Claypon soils in Southern port of Region 3. Very good drainage on these soils.

C-For excellent drainage in northern Minnesota,Wisconsin, Michigan. For very good agricultural drainage in Ohio, Indiana, Illinois,

Iowa northern Missouri, southern Minnesota,Wisconsin and Michigan. For good agricultural drainage in southern Missouri.

D-Forgood agricultural drainage in northern Minnesota,Wisconsin and Michigan. For fair agricultural drainage in Ohio, Indiana,

Illinois, lowo, northern Missouri, southern Minnesota,Wisconsin ond Michigon.

M —For fair agricultural' drainage in Red River Volley,Minnesota.

Reference "Drainage Specifications S~\'

FIGURE 11.4 DRAINAGE RUNOFF CURVES FOR OPEN DITCH DESIGN
11-17

from 1.0 foot for main outlets to 0.5 foot for lateral outlets. For example, if the depth of lateral outlet ditch, as

determined from Figure 11.6, pages 11-21 to ll-23a inclusive,

is fo\md to he 3.0 feet, then the actual constructed depth

should be 3-5 feet.

(2) Depth required for tile drainage.

Outlet ditches should be deep enough to accommodate tile

drainage systems. They should be deep enough to provide the

minimum depth for tile mains and laterals with at least one

foot of clearance between flow line of the tile at its outlet and the low water stage in the ditch. Assuming that

tile are laid at 3.5 to k.O feet the minimum depth of the

outlet ditch would be 5.0 to 5.5 feet. This added depth is

necessary in order to allow for silting that normally occurs,

and also provides a longer period for free outlet (unsubmerged) of the tile. However, if the outlet ditch is on such

a grade that silting will not occur and there is no low

water flow a few hours after a storm this clearance may be

reduced.

c. Determining Grade of Ditch Bottom

While there are a number of factors to be considered in arriving

at the grade of the ditch, it is usually determined from the

natural ground slope (in percent). This can be obtained by a

study of the plotted profiles. "When there is no natural ground

slope in the direction of proposed ditch flow, use a minimum

grade of 0.02^, or such other minimum grade as is specified in

the local Technical Guide.

d. Determination of Ditch Side Slopes

(1) The side slopes affect the capacity of the ditch and

therefore it is.necessary to choose the appropriate side

slopes before the ditch size can be determined. The soil

borings show, the kind of soil material that will be

encountered.. With the soil boring information and information from the fanner as to how maintenance is to be done the

side slopes can be decided from the standards specified in

Figiire 11.5, page 11-18.

(2) In clay and clay loam soil it is considered the best

practice to use 2:1 side slopes. However, in clay and heavy

soil, side slopes of 1^:1 may be adequate, or side slopes of

1:1 can be used on muck and peat soil since they tend to

stabilize on a steeper slope. . In deep sands where it is

impossible to establish vegetation a 1:1 side slope may be

used^ but the ditch section must be enlarged and deepened

over that required for design flow to allow for sloughing.

The amount of enlargement should be determined by an engineer. Under normal conditions ditchbanks cannot be mowed

safely on slopes much steeper than 3:1 or 3^:1^ depending on
11-18

DEPTH

4' Minimum for open ditch without

tile. 5' Minimum where used for

tite outlets.

^e I Minimum I ^\^

,sH^I^~

"^ '^ to I

DITCH SIDE SLOPE

Deep peats and mucks I to I side slopes may be used. Heavy clays I 1/2 to I side slopes may be

used but 2 to I preferable. If mowing is desired not less than 3 1/2 to I should be used.

BERM WIDTH

Minimum for shallow ditches ( 4 to 5* deep ) 10 feet.

For deep ditches.

1 to I slope use 2 X depth.

2 to I slope use I X depth but never less than 10 feet.

FIGURE 11.5 TYPICAL DITCH CROSS-SECTION

the type of equipment. Unless the slopes are flat enough to

mow^ or if the banks are not to be maintained by mowing

there is no particular advantage to a flat side slope. The

minimum slope for clay and clay loam soils should be that

required to establish a satisfactory cover.

e. Structures for Eoad Crossings

In addition to the design of the ditch cross section, attention

must be given to the design of culverts and bridges. Public

road culverts and bridges should be of sufficient size to pass

flood flows without excessive damage to the structure, highway,

and field crops. In addition, they should be of such a capacity

to pass the designed drainage runoff with the headwater and

tailwater carried below the ditchbanks.

Farm road crossings may be designed only for drainage design flow

if the landowner accepts responsibility of all damage for loss

of the structure or for overflow of adjacent land during floods.

Public road culverts and bridges should be designed by an engineer. The less complicated hydraulic designs for farm road

crossings as described in Part 11.80 may be undertaken by work

unit conservationists and conservation aids.

Erosion Control Structures

(1) Control of erosion is one of the major responsibilities

of the Soil Conservation Service. Service personnel must

not overlook this in the assistance they give in open ditch

drainage.
11-19

(2) Provisions should always be made for lowering surface

water from adjoining fields to the ditch. This may "be

accomplished by installing chutes^ drop spillways, pipe drop

inlet spillways, or other suitable structures.

(a) Vegetated chutes may be used where the volume of

water is small. Vegetated chutes must be mowed frequently to maintain a good dense sod. If a vegetated

chute is used on a ditch of constant flow, the toe must

be raised above no3rmal water level and protected with a

toe wall to prevent unraveling of the sod. The toe of

the chute should be recessed into the bank a distance

of 10 feet from the edge of the ditch bottom and then

raised on a slope not steeper than 8:1. Design of sod

chutes is covered in Part 10.50.

(b) Pipe drop inlet spillways may be used advantageously to convey water from back of a levee or continuous

spoil bank into a drainage ditch. Where a ditch passes

through an area of flat land without definite concentration of surface flow into the ditch, lateral drainage from the adjacent land can usually be provided by

standard pipe drop inlets with a pipe size of at least

12" in diameter placed at the low points but not to

exceed 1,000 feet apart along the ditch with the inlet

back of a levee or spoil bank.

(c) Where definite concentrations of surface flow into

the drainage ditch are found to exist, special designs

will need to be made.

(d) Where the volume of water to be handled is large,

drop spillways of reinforced concrete, masonry, or concrete block should be used. Suitable inlet structures

should be provided to protect the head end of the ditch

from eroding.

g. Example of Ditch Design

With the above information the required cross section of the

ditch can be determined from Figure 11.5> page 11-18, and

Figure 11.6, pages 11-21 to ll-23a inclusive.

(1) Example:

300 acre watershed

Location - northern Iowa

Land slopes less than 25 ft./mile (1/2^)

Common field crops to be grown

Ditch to be used for tile outlet
11-20

Use C" curve Figure 11A

Eequired drainage design discharge Q = 28 c.f.s.

Borings show material to range from silty clay loam to clay

loam down to k foot average depth, and grading from clay

loam to clay from k foot to 6 foot depth• Cooperator pre -

fers to control vegetation by chemical spray method. From

Figure 11.5^ side slopes not steeper than 1¿:1 are required.

The minimum "bottom width that can be dxig with a dragline is

^.0 feet. Natural ground slope from profiles = O.O65Í. From

tables Figure 11.6, k foot bottom ditch, 1^:1 side slopes,

3 feet deep will carry 33 c.f.s., but ditch is to be used

for tile outlet and will require 5 foot minimum depth.

Specify k foot bottom ditch, 5 foot depth, with l|:l side

slopes.

Completion of Ditch Plan

(1) If the final designs and specifications are not within

reasonable agreement with the preliminary investigation, a

further contact should be made with the cooperator and an

agreement reached before proceeding with the final detail

plans. When a cooperator understands Service standards and

the reasons for them he is more apt to follow plans and

specifications.

(2) After the cooperator has agreed to accept the designs

and specifications, complete the plans by adding the following information:

(a) Record ditch design computations on plan profile

sheet.

(b) Draw ditch bottom grade on profiles (generally

parallel to natural ground slope).

(c) Eecord computed quantities (earth excavation and

other). (See Part 1.53 for computation of yardage.)

(d) Draw up typical cross sections to show ditch bottom width, side slopes, berm width, and spoil leveling

specifications.

(e) Eecord any other pertinent data and specifications.

(See Figure 11.3 for typical data sheet of above

example.)

(f) Design and complete structure data sheet or use

standard designs. (See Figures 11.7 and 11.8, pages

11-21^ and 11-25.)
OPEISI DITCH DESIGN TABLE FOR DITCHES WITH 1 TO 1 SIDE SLOPES

DITCH SIZE ^^"^^ .02% .04% .06 % 08% .10% .15% .20%

Bottom

Width

Feet

Depth

in

Feet

Top

Width

Feet

Area

Square

Feet

"Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

c.f.s.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

C.f.s

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

c.f.s.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

c.fs.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

C.f.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

B C D M B C D M B c D M B c D M B c D M B C D M B G D^ M

4 O.S 5.Ô 2.25 07 4 6 09 «> -11 - 11 n <^ 13 1 3 10 15 15 15 9 12 18 18 1 8 II 14 21 21 2.0 12 lb 24 24

4 !.0 6.0 5 00 ?\ !2 HT^ ?5 ?5 ■■3 0 HR- 24 ^^6- 36 37 22 29 A< 44 43 26 -34 ^-51 51 48 29 38 57 57 58 35 46 73 73 6.7 40 54 86 86

. 4 1.5 7.0 8.25 44 26 33 52 52 36 49 78 76 75 45 62 99 99 87 52 72 119 123 97 58 82 136 146 12.0 72 105 176 206 14.0 83 125 212 272

4 20 8.0 12 00 72 43 59 94 94 10.0 60 85 140 153 13.0 77 115 194 238 15.0 89 135 231 315 16.0 146 250 20.0 119 190 345 555 23.0 137 227 455 700

4 2.5 9.0 16.25 i.O 66 95 158 178 16,0 95 146 250 360 190 113 179 319 SlO 220 131 214 415 650 25.0 149 254 5; 5 30.0 180 330 fAO lüób 350 213 43Ü 940 I2bü

4 3.0 10.0 21.00 6.0 95 146 250 360 22.0 131 214 415 650 270 161 283 620 890 31.0 187 3«)n 780 213 430 9' 0 1250 430 265 640 1260 49.0 300 810 1445 1870

g 05 7.0 3>5' 1.0 6 8 8 II 17 17 1.7 10 13 20 20 2.0 12 16 13 17 26 2.7 16 21 32 32 3.1 18 25 37

6 .0 80 700 3? 19 25 38 38 44 ?6 35 52 52 54 32 43 67 67 6.3 38 51 80 42 57 91 91 86 51 71 117 121 99 59 14 139 150

6 9.0 11.25 6.3 38 51 80 80 8.9 53 74 122 128 11.0 66 95 I5Ö 178 13.0 77 115 194 14.0 83 125 212 272 17.0 101 157 271 410 119 190 345 555

6 2.0 10.0 16.00 10.0 60 85 140 153 15.0 89 135 180 107 168 293 460 21.0 125 202 377 600 230 137 227 45 5 700 28.0 167 298 660 935 330 200 3J5 880 1180

6 2.5 II.O 160 95 146 250 22 0 131 214 415 650 161 283 620 187 350 780 1080 35.0 213 430 940 1250 429 260 610 1220 1540 49.0 300 8 0 1445 1870

3.0 12.0 2700 p?o 131 ?I4 4lf> 300 180 330 740 1035 ??f7 47 f> 265 IP60 1^8^ 48.0 295 7?0 1410 1820 59.Ü 389 1999 1800 ?320 470 13 0 2149 2760

8 0.5 4.25 1.3 10 15 1.8 1 1 14 21 21 14 15 21 31 31 2.9 17 23 35 35 3.6 21 29 43 43 41 24 33 49 49

3 10 0 900 41 ?4 33 49 49 59 35 47 75 75 72 43 59 94 94 84 50 114 116 93 56 78 129 137 11,0 66 95 158 178 13.0 77 115 194 238

8 II.O 14.25 8 3 50 69 112 1 14 1 20 7? 105 176 206 I4Ô 83 125 212 272 170 101 157 271 410 190 113 510 23.0 137 227 455 700 260 155 268 575 840

8 2.0 2000 140 83 l?5 212 272 190 113 179 319 240 143 495 745 270 161 620 890 30.0 180 330 1035 225 475 1015 1320 43.0 265 640 1260 1585

8 3.0 26.25 200 119 190 345 555 28 0 167 298 ~mp 213 940 1250 40.0 245 555 1140 1450 450 695 1320 550 345 975 1650 2140 63.0 420 1200 1950 2520

8 3.0 40 33.00 27.0 161 283 620 890 39.0 240 530 1100 1405 480 295 1410 1820 345 975 1650 2140 Ç'O II4Ç 1999 2429 750 550 1490 2490 3110

10 0 5 1.0 5 25 16 1Ó 1^ 1^ l<^ ?S l4 18 27 27 28 17 33 33 20 26 39 39 37 29 44 44 45 36 54 54 51 30 40 62 62

10 1.0 ?0 11.00 5.2 31 41 64 64 74 44 ef -97" 97 -54^ 124 130 loó 60 85 140 153 120 72 105 176 206 140 83 125 212 272 170 101 157 271 410

10 1.5 30 17 25 10.0 60 85 140 153 14.0 83 125 212 272 18.0 ro7 168 293 460 21.0 125 202 377 600 137 227 455 700 2ao 167 298 660 935 330 200 385 880 1180

10 2.0 40 2400 170 101 157 271 410 240 143 240 495 745 290 173 314 700 985 330 200 385 880 1180 370 225 475 1015 1320 460 285 725 1340 1720 53.0 330 915 1580 2050

10 25 5.0 31.25 25.0 149 254 535 795 350 213 430 940 250 430 265 640 1260 1585 490 300 810 1445 1870 550 345 975 1650 2140 680 470 1330 2140 2760 78.0 590 1570 2520 3260

10 3.0 6.0 3900 34.Ô 206 405 900 1225 48.0 295 780 1410 820 59.0 ??(? 1990 18PQ ?320 679 4Ç0 1300 2I9<? 271Ç 75,0 .550 J..4?_Q.., 2400 lliÖ. .â2û- 929 1929 ?999 4999

DITCH SIZE ""^^ .25% .30% .35% .40% .45% . 50%

Bottom

Width

Feet

Depth

in

Feet

Top

Width

Feet

Area

Squore

Feet

"Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

c f. s.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

cf s.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES "0"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

B C D M 6 C D M B C D M B C D M B c D M B C D M

4 0.5 5. 2,25 2.3 14 18 27 27 2.5 15 20 %0 "30 2.7 16 21 á2 32 17 23 35 35 3.1 18 25 37 37 3.3 20 26 5è äd

4 1.0 6.0 5,90 75 45 62 99 99 8.- 50 69 112 114 89 53 122 12 57 80 132 142 10.0 60 85 140 153 11.0 66 95 158 178

4 1. 5 7 1 8.25 15.0 89 135 231 315 17C 10 1 157 271 410 180 107 168 293 461 19.0 113 179 319 510 21.0 125 202 377 600

4 2 0 8.0 155 268 575 840 280 167 298 660 935 30.0 180 740 1035 330 200 385 880 1180

4 2 5 9 0 16 25 39.0 240 530 MOO 1405

4 3 0 10.0 21.00

6 0.5 7( 3.25 35 21 28 42 42 3.8 23 30 45 45 4.1 24 33 49 49 4.4 26 35 52 52 46 27 36 55 55 4.9 29 39 58 58

6 1 0 80 66 95 158 178 12.9 72 105 176 206 13.0 77 1 5 19^ 2 38 14.0 83 125 212 272 15.0 89 135 231 315 16.0 95 146 250 360

6 1.5 9.1 ir.25 22.0 131 214 415 650 24.0 143 240 495 745 260 155 2Î8 575 840 280 167 298 660 935

6 2.0 10.0 16.00 370 225 475 1015 1320 490 245 555 1140 1450

6 11.0 21.25 550 345 975 1650 2140

6 3.0 l?0 2700

8 4.¿S 4.è 27 S6 56 tt 5 0 30 40 61 61 5.4 32 43 67 67 5.9 35 47 75 75 62 37 50 79 79 6.5 38 52 84 84

8 1.0 10.0 9.00 15.0 89 135 231 315 160 95 146 250 360 170 101 157 271 410 190 1 13 179 319 510 20.0 119 190 345 555 21.0 125 202 377 600

8 1 5 11.0 14.25 29.0 173 314 700 985 320 193 36 5 820 II 30 350 213 430 940 1250 370 225 475 1015 1320

8 Z.0 12.0 20.00 48.0 295 780 1410 1820

8 2.5 13.0 2625

8 3.0 14.0 33.00

10 as II.O TIT Ü.8 -35- 46' 73 -73 6 3 38 51 BO' 80 -6.8 40" 55 88 88 74 44 61 97 97 77 46 63 102 102 8.2 49 68 110 112

10 12.0 11.00 18.0 107 168 293 469 290 1 19 190 345 555 220 131 214 415 650 23.0 137 227 455 700 25.0 149 2 54 535 795 260 155 268 575 840

10 1.5 13.0 1725 360 220 450 975 1280 40.0 245 555 1140 1450 43.0 265 640 1260 1585

10 ^o 4 0 24.00 59.Ô 380 1090 1800 2320

10 2.5 5.0 31.25

10 3.0 6.9 ?9.99

NOTETHE LETTERS B,C,D 8 M

UNDER SLOPE, REFERS TO THE

DRAINAGE RUNOFF CURVES.

FOR SELECTION OF PROPER

CURVE TO USE REFER TO

DRAWING NUMBER 3-L-14657,

FIGURE NO. 11.4

Compiled by.-

SHERMAN, DEAN

TRUEBLOOD AND ROBISON

U.S. DEPT. OF AGRICULTURE

SOIL CONSERVATION SERVICE

REGION BE

MARCH 11,1952

H

I

ro
I

ro

OPEN DITCH DESIGN TABLE FOR DITCHES WITH I >2 to I SIDE. SLOPES

DITCH SIZE

BottOfn

Width

Feej

-per

10

10

Depth

in

Feet

2.0

2.0

"TÜ- is:r

Tïï-

"Xü-

"^5-

TTT

XS"

32:

Top

Width

Feet

S

13.0

HEus: "Tr

12X

IM: TFTw

"ITT

11^

.02%

Areo j "Q

Square|^,^

Feet i|c-f-s.

M9.38

2.3

5.0

14.00 II 8.5"

l9.3è i 130

m n^jö

y.5Ó i 33

12.38 i 6.8"

18.00 i 12.0

24^38 i 17.0" wm9.50 i 4.4"

15.38 i 8.8"

22.00 15.0

2938 22.0

m ¿Lfi.

1X50" -ü18.38 ¡H.'O"

26.00 iie.ô

34.30 [270"

4?.?9i?7,<?

WATERSHED HANDLED

BY DRAINAGE CURVES

Lia.

ill.

¿2a.

ili

2ä±

135.

SèS.

álL

194

~39

52^

231

SÄü^:

-#

M¿.

510

"39

233.

125

ÎSiâQ.

890

iIZSL

.04%

"Q"

Cf. S.

27.0

¿&£L

ëT^

41Û.

76-

380

^M.

WATERSHED HANDLED

BY DRAINAGE CURVES

220

TT

22Û.

35:

1^

TT9"

283

254

Asa

35Ô"

^

Al¿.

176

-W

250

535

JLLS.

^

l¿a£L

"^Ô

3r&

.S90

^«^

360

795

i23Si

1080

Tgr

205Q

.06%

"Q"

cf. s

230

¿M

"58"

2Qör

300"

^í2Ji

140

26.0

IMm2T

93

19.0

3r&-

£2iL

WATERSHED HANDLED

BY DRAINAGE CURVES

"SO

2QSL

TW

TBT

iáíL

aa¿

190

330

^

T25"

SâtSL

255.

231

4^5

176

345

740

212

"575-

1055

T8Ö

20?0

315

1180

206

55F

1S35.

Tn

m^

1080

¿em.

.08%

27Ü"

lâiL

T4:ô

£2^

ÎTÔ

36.0

750

WATERSHED HANDLED

BY DRAINAGE CURVES

ilia

137

213

16

im:

5S£L

^83

Si^SL

227

430

310 835

72

665-

450

Hâfi.

ii£íl

~86

ilM.

119

293

1^[2£L

24QP

Hu¿

ia2ÍI

123

1630

¿±t

1280

2Í00

¿IIQ.

.10%

"Q"

cfs.

-&2

.á2il

5èSL

\t5

24.0

4Q0

â±a

WATERSHED HANDLED

BY DRAINAGE CURVES

¿£¿.

15Ä.

Ig.

143

245

SäSi.

MSL

iÎ2Û§.

835

^

105

240

555

.319

1¿§&.

1100

lia

1480

W176

495

1140

¿lêQ.

1035

1M¿

_27

¿iâO.

-36

148

¿S2i1

ISSiS.

.15%

"Q"

cf. s.

_Lâ.

23^

36il

325.

£SJI

i¿0

24.0

40.0

61.0

â&iL

490

740

I92.Q

WATERSHED HANDLED

BY DRAINAGE CURVES

_18

193

300

âSSL

T¿

J2SL

535

aa¿

810

1350

121

-Sil

1580

1445

^

1880

2850

5^Q_

ÜI

2a¿íl

3680

1870

3060

455Ö1

.20%

"Q"

c f s.

rro"

370

Zä£L

S

WATERSHED HANDLED

BY DRAINAGE CURVES

_43

260

£25

490

.32

-6^

mi

475

m.

125

298

.42

L57

1030

250

1220

Í88U. 212fiL

158

¿a1

.271

2800

"26

890

118

1520

2190

'^

"272

.935

2860

_êê.

41Û

223fi.

3630

DITCH SIZE .25%

Bottom

Width

Feet

10

Depth

.Û5_

JLÔ_

2.5

3.0

"5TJLSL.

.Ä5_

2.0

T5-

_2JB_

Top

Width

Feet

.^^

JLL5.

"TT

135

iS^

N.O

15.5

315:

13.0

JM:

JâO.

HSö

19.38 47Ö

"IF

12.38 I 240"

18.00 I 41.0

24.38 620"

STSOl

_438.

TM

15.0

.JJ.

11.50 I 190

18.38

26:c

390

43 50 II

WATERSHED HANDLED

BY DRAINAGE CURVES

290

"^

143

3s:

113.

240

-20

68

S

105

Ha.

530

740

"7T

3i:

.119.

m^

Jèo

-^

1035

-TS

2460

080

_z:5.

-Siil

252Ö

.30%

"Q"

cf. s.

-2Z.

19.0

"M.

13.0

:M

34.0

_ê5.

1LÔ.

WATERSHED HANDLED

BY DRAINAGE CURVES

~54

200

TT

:3a

1¿5.

179

405

2(Î2.

31

"64

^Tf

_S±

.377

"IF ISÜ"

ÏJM

-ÎÏÏ'

S

.35%

"O"

c f s.

21.0

seiü"

WATERSHED HANDLED

BY DRAINAGE CURVES

TT

83

17T

107

225

T3

82

2Ö2

_33

T7

227

725

136

975

600

w

MF

-70

.40%

"Q"

Cfs.

"31

10.0

22.0

WATERSHED HANDLED

BY DRAINAGE CURVES

"89

11T

m:

350:

"37

153

TTT

1450

.45%

"Q"

cfs.

4.8

16.0

2LÛ.

_ao

WATERSHED HANDLED

BY DRAINAGE CURVES

"20

125

107

m:

.50%

"0"

c f. s,

-1^

WATERSHED HANDLED

BY DRAINAGE CURVES

31

757

JÖ.

1? "?r

^06

Trer

"86

65Ö

890

NOTE:

THE LETTERS B,C,D a M

UNDER SLOPE, REFERS TO THE

DRAINAGE RUNOFF CURVES.

FOR SELECTION OF PROPER

CURVE TO USE REFER TO

DRAWING NUMBER 3-L-14657,

FIGURE NO 11.4

Compiled by:

SHERMAN, DEAN

TRUEBLOOD AND ROBISON

U.S. DEPT. OF AGRICULTURE

SOIL CONSERVATION SERVICE

REGION m

MARCH 11.1952

3-L-27860
OPEN DITCH DESIGN TABLE FOR DITCHES WITH 2 to 1 SIDE SLOPES

DITCH SIZE ^*^î^ .02% .04% .06% .08% .10% .15% ,20%

Bottom

Width

Feet

Depth

in

Feet

Top

Width

Feet

Area i "Q"

Square .

Feet ^^^^

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

cf. s.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

Cf. s

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES

B c D M B c D M B C D M B c D M B C D M B C D M 8 c D M

4 05 CO ^ 50 OV 4 e \ $ 1.0 ë ^ 1? 1? 1? 7 «> 14 14 l4 3 M 17 IT 16 10 »3 19 t9 ^<s li» 16 24 ?4 ?3 14 IR ?7 27

4 l-P 6.00 2.5 15 3Ô 30 3 21 28 42 42 43 26 34 51 51 5.0 30 40 61 6Í 56 3.3 44 70 68 40 55 88 ftR 79 47 65 106 106

4 \.l 10.0 10.50 5.0 30 40 61 61 8. 48 107 107 90 54 75 124 130 no 66 95 158 178 120 72 105 176 206 150 89 135 231 315 170 101 157 27! 410

4 2.0 12.0 16.00 10.0 60 85 140 153 140 83 125 212 272 170 101 157 271 410 190 113 179 319 510 131 214 415 270 161 283 310 350

* 2.6 140 2250 15.0 89 135 231 315 22. 131 650 270 161 283 620 890 31,0 187 350"^ IORÖ 206 405^ 42 0 260 1220 1540 300 RiöH 1445

*

ÎÏ 16.0 30.00 23.0 137 227 45Î5 700 '^! 320 1130 39.0 240 530 iiqO 1405 450 290 69? 1320 51.0 315 865 1515 6?Q 419 1175 1920 510 1420 2960

0.5 8.0 3.50 I.I 7 9 \l l3 à 18 lé I.Ô 1 1 i4 ¿1 21 21 12 17 25 23 14 18 27 29 17 35 39

1.0 ÍO.Ü Ô.O0 3.5 21 28 42 42 5.0 30 61 6( 6.1 36 49 78 Té 70 42 57 g 78 46 64 104 104 9.6 57 81 134 144 66 158

12.0 13.50 70 42 57 91 91 10.0 60 140 163 13.0 77 il5 194 238 150 89 135 23 315 16.0 95 146 360 20.0 119 190 345 555 137 227 45r 700

2.0 20.00 13.0 77 115 194 238 18.0 107 168 ¿93 4éô 22.0 I3i 214 4Í5 650 260 155 268 575 840 173 314 350 430 940 1250 245 555 1140 1450

2.5 I6.Ü 27.50 20.0 119 190 345 555 28.) 167 298 660 935 340 206 405 9Ô0 1225 400 245 555 1140 1450 270 665 1300 940 1620 2100 62 0 4Í0 1175 1920 2460

3.0 !^-9L 36.00 28.0 167 298 6^2 935 4Q0 245 555 n40 1450 49.0 300 810 1445 1870 570 365 1030 1730 430 1225 780 1570 2520 900 3000 3900 Ö.5 IÖ.Ü 4.é0 1.4 Ô II 17 II IS ¿3 ¿3 2.3 —,4" ■■1&' -^ ¿7" -zT-|6 5T "12" ""TR^ "25" 37 '-?qH 44 43 26 34 51 51

1.0 12.0 10.00 4.5 27 36 54 38 82 82 79 47 65 106 106 9 1 54 76 126 132 10.0 60 85 140 12.0 72 105 176 83 125 212 272

1.5 14.) 16 50 9 0 54 75 124 130 130 77 194 238 16 0 95 146 250 360 19,0 113 179 ^3-9 510 21.0 125 202 377 155 268 -575- 300- 330

8 2.0 1^- IHS '^-^ 95 146 360 137 455 700 280 167 298 660 935 -820 1130 450 975 1260 44.0 27Ö 1630- 310 835 1480 1920 \ 2.5 18. 32.50 24.0 143 240 495 745 2Ö6 900 1225 42.0 260 610 l??0 1540 490 300 810 1445 1870 9^ 0 1620 2100 670 2100 770 575 1540 2490 3210 ' VI 34.Ç 2QÇ 405 900 122$ 49? 300 ^IQ 1445 1870 §9,Ç -39Ö ?{?ja 690 480 n^f 1540 2490 950 3210 4170

10 ü.b ¿.Ô 1.7 10 13 20 '20 ¿4 14 19 29 29 ^W iT * 35 34 20 27 ; "o" 45 4.6 55 53" " 32" 42 66 66

1 ' « P 14.0 b.b 33 44 68 68 7 8 46 64 104 104 96 57 Rl 134 144 no 66 95 158 178 12.0 72 105 1176 150 231 180 107 168 293 460

10 k5_._ 19.50 1.0 66 95 158 178 16.0 95 146 250 360 119 190 345 555 13:0- 137 227 455 700 268 -575- 840 31.0 187 350 780 ||OQQ 360 450 ^975 1280

10 Z.0 lao 9.0 113 179 319 510 270 161 283 620 890 33.0 200 880 1180 380 230 500 1055 265 6. 0

u^

1585 320" 890 610 400 1145 1880 2420

10 2.5 20.0 37.50 29.0 173 314 TOO 985 41.0 159 580 1180 1495 50.0 310 835 1480 1920 58 0 375 IO6Ó 1770 650 440 r255 2610 790 605 1590 2570 910 805 1900 3950

Í9 ?r9 1 48.00 »41.0 Ji¿SL JLg2. i 180 iiâ& .iaö_ ?r5.. 10^0 J.770 g27Q 71.0 SOQ II4QQ 226Q 2920 SLO 635 1650 .2640. .342a 805 1900 395Q. U l,û. 1150 2410 3850

DITCH SIZE "*^^ .25% .30% .35% .40% .45% .50%

Bottom

Width

Feet

Depth

in

Feet

Top

Width

Feet

Area "Q"

Square

Feet Cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES

cf.s.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

Cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

Cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

Cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES "0"

Cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES

B c D M B C D M B c D M B c D M B c D M B C D M

4 0.5 2.50 2.5 IS 20 3Ö 3Ó 2.8 17 22 33 %\ 5.(5- |8'

..,.

36 -jr V?^—w^ 25-^ 3A 38 " 3-4 20 ^ 27 40

, 36 21 29 43 43

4 6.00 8.8 52 73 121 125 97 58 82 136 146 10.0 60 89 140 16^ 11.0 66 96 160 181 12.0 72 104 174 203 120 76 no 185 -177

4 1.5 10.0 10.50 19.0 113 179 319 510 21.0 125 202 377 600 230 137 227 455 700 24 0 143 24Ö 495 745 26.0 155 268 57.5 840 270" 161 283 620 890

4 2.( 12.0 16.00 340 206 405 900 l?25 38.0 500 1Ô6S 1360 40.O 245 555 1140 1450

4 14.0 22.50 54.0 335 940 1620 2100

4 16.0

6 0.5 80 3.50 3.7 29 44 44 4.Ô 24 3¿ 4Ó 48 4- 2i> 3è éS ir 4t ¿'8 7 ^6 56 4.9 29 39 58 58 53 32 42 66 66

6 1.0 K.O 100 12.0 105 176 222 14.0 83 125 21 2 261 16C 135 231 306 160 95 |i g 246 351 170 99 157 267 400 170 10-4 168 286 445

6 1. 12.0 i:.50 26.0 268 575 840 290 173 314 31 ( 187 350 780 1080 330 200 31 5 880 1180 340 206 405 900 1225

6 2. • 20.00 45.0 280 695 1320 1675 50.0 310 835 1480 1920

6 2.5 MÎ.P 27.50

6 3 0 -1 iL. 36.00

8 0.5 4.50 n P 38 57 57 59 32 42 66 66' 5-7" -34 ^ 45 ^T? "7? 6 1 ^ 36 "49- 78 78 '64 38" r,52" - 82 8-2 -6è' 40 "55" 8^ "88

8 1.0 12.0 10.00 16.0 05 146 250 360 18.0 107 168 293 460 19.0 113 179 319 510 200 119 190 3-5 555 22 0 131 214 415 650 230 137 227 455 700

8 1.5 1 ;ü 16.50 330 200 395 880 1180 370 225 475 1015 1320 39,0 2.40 530 1100 1405 420 260 610 1220 15-10

8 2.0 16.0 24.00 56.0 355 1005 1690 2190

8 ?^ 1 .0 32.50

8 3.0 42.0(

10 0.5 12.0 551 é.ô 36 48 76 76 6.5 38 52 84 84 70 42 57 91 91 76 45 62 101 161 80 48 "66 Itíf 107 '8 5 50 70 116 llT

10 1.0 14.0 12.0 20.0 190 345 555 22.0 131 214 415 650 230 137 227 455 700 25.0 149 254 535 795 26,0 155 268 575 840 280 167 298 660 935

10 1.5 1 .50 400 245 5^^ 1140 1450 440 270 665 1300 1630 480 295 780 1410 1820

»0 2.0 18.0 ^^L 67.0 460 13ÔÔ 2100 2710

10 2.5 20-0

IÇ ?P J-Q„ 1 , „ .

NOTE:

THE LETTERS B,C,D ft M

UNDER SLOPE, REFERS TO THE

DRAINAGE RUNOFF CURVES.

FOR SELECTION OF PROPER

CURVE TO USE REFER TO

DRAWING NUMBER 3-L-14657,

FIGURE NO. 11.4

Compiled by:

SHERMAN, DEAN

TRUEBLOOD AND ROBISON

U.S. DEPT. OF AGRICULTURE

SOIL CONSERVATION SERVICE

REGION m

MARCH 11,1952
OPEIM DITCH DESIGN TABLE FOR DITCHES WITH 3 to 1 SIDE SLOPES

1

ro

DITCH SIZE ^ .02% .04% .06 % .08% .10% .15% .20%

Bottom

Width

Feet

Depth

in

Feet

Top

Width

Feet

Area "Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

cf.a

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

c.f.s.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

c.fs.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

cf s.

WATERSHED HANDLED

BY DRAINAGE CURVES

B C D M B c D M B C D M B c D M B C D M B C D M B C D M

2 V-^ -4AU-44Pr _U,ö ,t>.. i-^ yo .J.I 7 9 1^ l¿ l.¿ 8 10 15 15 1.5 è 12 18 18 1.7 10 13 ?o 20 ¿.1 12 17- ¿5 ?5 ?4 14 19 ?9 ?9- 1.0 ¿.Ö 33 66 4.U 24 32 48 48 4.9 29 39 bB 58 5/ 34 45 72 72 6.3 38 51 80 80 78 46 64 104 104 90 54 75 124 130

4 , lb 13.0 12.75 7. 1 42 91 91 9.0 54 75 124 130 II.O 66 95 158 178 13.0 77 115 194 238 150 89 135 ?3I 315 18.0 107 168 ?93 460 20.0 119 190 -^ 555" i ^•^ -ISÍ) I2S2 !l- • fï 1/6 206 17 0 01 157 271 410 21.0 125 202 377 600 24.0 143 240 495 745 270 161 283 620 193" "365- 1130 38.0 500 1055 1360 4 2.5 19.0 28.75 19. i 113 179 319 510 270 61 283 620^ 890 330 200 385 880 1180 240 530 1100 1405 42.0 260 610 l??0 1540 330 915 1580 610 ^00 1880 2410 4

?;. 22.0 39.00 29.0 i-'^i_¿I4 /0Ü 98b 41.0 250 580 1180 1495 51.0 315 865 1515 I960 59.0 380 1090 1800 2320 65.0 440 1255 2030 2610 620 1620 2600 3360 93 0 840 1950 3130 4050

-TTT-- I^O ME -44^ 7 13 1.5 9 h44- 18 i*í !? 1 1 15 23 13 17 26 26 a4 14 19 29 29 18 36 36 3.4 20 ?7 40 40 I.T5 12.0 a..uu -éf^ 23 30 uiy 45 .^•fí 32 43 67 h.*'' iH iiy. .^.t .... 8_b 86 76 45 62 101 101 8.5 50 70 116 118 10.0 60 140 153 12,0 72 105 176 ?06 —1 i. 5 —OTñ— lun 15.75 HO 48 66 107 107 12.0 72 105 4^ 206 lb.U 89 135 231 315 170 101 157 2/1 410 19.0 1 13 179 319 510 230 137 455 700 26.0 155 268 575 840 24.00 l^-.V .*i^L -^ 600 26.0 155 268 575 840 30.0 180 330 /4Ü 1035 330 200 385 880 1180 41.0 250 580 1 180 1495 470 290 755 1375 1770

-4n-i í?í?> -r'í^ à60_ ¿UU 385 880 iL8q 41.0 250 580 1180 1495 470 290 755 1375 1770 53.0 330 915 1580 2050 65.0 440 1255 2030 2610 75 0 550 1490 2400 3110 6

-^^ ify^ ^i?-V^ ób.U ¿1Ó 4ÓU 940 l.^ibU 310 835 I48U I92U 61.0 400 1145 1880 ZOO 490 1370 2860 78.0 590 1570 2520 3260 <?60 899 3250 4??0 III.O 1150 ?4I0 3«50 5030 8 0.5 1 1.0 4.75 _. 1.4 8 1 1 1 7 17 ^•fí !^ ..lb 24 24 2.4 14 19 29 2.9 17 23 35 32 19 25 38 3B 46 46' 45 36 54 8

ll-y. .'ivy- 4.« 29 38 57 57 6.8 40 55 88 88 84 50 70 114 116 9.8 58 83 148 11.0 66 95 158 13.0 115 194 238 150 89 315 8 J.U.U... 60 85 140 153 15.0 89 135 231 31b 18.0 107 168 293 460 200 119 190 555 23.0 137 227 700 167 ?9ñ 660 935 3^0 200 880 IIRO 8 2.0 20.0 ^SVIr* 18.0 1 107 168 293 4bü 2b.O Ibb 268 b/b 840 31.0 187 350 780 1080 450 1280 4Q0 245 1 140 1450 810 1445 1870 57 0 1030 I73Ö 2230 8 2.5 23.0 ..¿a/b 28.0 lb/ _298 660 93b 40.0 bbb 1140 1^50 490 300 810 1445 1870 355 1005 1690 2190 64.0 430 1225 2560 575 1540 ?490 770 ÍR50 2970 3840

8

3.Ö 26.0 51.00 41.0 2bU ^U 1180 149b 58.0 375 1060 l//p 22/0 /I.O 509 1400 2260 650 1670 2680 3470 820 1920 4000 112.0 1170 2430 3900 130 0 1460 2910 4640 0.5 3iO IZ^ '-8 1 1 14 2.5 lb 2Ü 30 30 3.0 "Ts" 24 36 21 28 42 42 23 46 46 4R' ?9 33" ~44" 6R

0

1.0 &0 13.00 5.9 ¿b 4f 75 75 83 bO 69 112 114 10.0 60 85 140 153 12.0 72 105 176 206 13.0 77 115 194 238 16 0 95 1 46 360 19.0 1 1 3 179 -3T9- ,^ 1.5 19.0 21.75 12.0 72 lUb 176 206 17.0 101 157 271 410 21.0 125 202 377 149 254 535 795 27.0 161 283 620 890 34 0 ?06 405 900 1225 39 0 240 530 lion 1405 0 2.0

h#7T- 32.00 21.0 12b 2U2 377 6ÖÖ .áO.(J.. Viï 330 /4Ü 1035 370 225 475 1015 1320 42.0 260 610 1220 1540 470 290 755 1375 1770 58.0 375 1060 1770 2270 670 460 1300 2100 2710

0 i-^ 25.0 iîl% ^19. '^V.Vr -^.ii ..880 444^- 4b.U 285 725 1340 1720 570 365 103U 1/3Ü 660 450 1280 2060 2660 73.0 520 1450 3010 90.0 790 1870 3000 [3900 104.0 1030 2230 3570 4660

0 30 _ 28.0 5700 470 J^b \à/b 1 / /.o, b/.U 4bU IÓUÜ L2IU0 2/IU „82i)„ _bb0 Ib/U 2680 940 .855, 19/0 3170 4110 105.0 1950 2259 3610 4719 ia9.Q 1449 2999 4600 5980

DITCH SIZE "*^i^ .25% .30% .35% .40% .45% .50%

Bottom

Width

Feet

Depth

in

Feet

Top

Width

Feet

Area "Q"

Square

Feet Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

cf s.

WATERSHED HANDLED

BY DRAINAGE CURVES

cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES 'Q"

Cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES "o"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

B c D. M B C D M B C D M B C D M B C D M B C D M

4 0.5 7.0 2.75 2.7 16 21 ; 2 32 3.0 18 24 36 36 3.2 19 25 38 3Ô 3.4 20 40 40 3.7 22 29 44 44 39 ?3 31 46 46-

4 1.0 10.0 700 10.0 60 85 l-iO 153 II.O 66 95 158 178 12.0 72 105 172 200 13.0 75 111 185 225 13.0 80 119 201 252 140 8' 125 ?I5 278

4 1.5 13.0 12.75 23.0 137 227 455 250 149 254 535 795 270 161 283 620 29.0 173 314 700 985 31.0 187 350 780 1080 3?0 19- 365 820 1130

4 2.0 16.0 2Q00 420 260 610 1220 1540 460 285 725 1340 1720 5Q0 310 835 1480 1920

4 19.0 28.75 68.0 470 1330 2140

4 3.0 ??0 39.00

6 0 5 90 3.75 3.9 L 23 31 46 46 42 •3 50 50 4.5 36 54 54 4.8 29 38 57 57 5.1 30 40 62 62 5.4 32 43 67 67

6 1.0 2.0 9.00 14.0 1 83 1 25 212 272 15.0 135 231 315 160 146 250 360 170 101 157 271 410 18.0 107 168 293 460 19.0 113 179 319 510

6 1.5 5.0 15.75 3Q0 180 330 740 1035 33.0 3i 5 1180 35 0 430 940 1250 38.0 230 500 1055 1360 40.0 245 555 1140 1450

6 2.0 80 24.00 53.0 330 91 5 1580 2050 58.0 375 1060 1770

6 25 33.75 84.0 685 1720 2760 3580

g 3.0 24.0 45.00

05 11.0 4 75 5.0 30 40 61 6! 5.5 33 44 68 68 5.9 35 47 75 75 6.4 38 5? 82 82 67 40 54 86 86 71 42 58 9? 92

14 0 .00 17.0 10 1 157 410 19.0 113 179 319 510 200 119 190 345 555 22.0 131 214 415 650 23.0 137 227 455 700 24 0 143 240 495 745

1.5 170 36.0 220 450 975 40.0 245 555 1140 1450 43.0 265 640 I26C 1585 460 285 725 1340 1720

2.0 200 2 .00 64.0 430 1225 2000 70.0 490 1370 2220 2860

2.5 23.0 3875 100.0 960 2130 3400 4440

30 260 5.99

0 0 5 130 5.75 é.¿ 37 50 79 79 67 40 54 86 86 72 43 59 94 94 78 46 64 104 104 82 49 68 no 112 8,7 5? 72 119 l?3

0 1.0 16.0 13.00 21.0 125 202 377 600 23.0 137 227 455 700 250 149 254 535 795 26.0 155 268 575 840 28.0 167 ¿98 660 935 290 173 314 700 985

0 1.5 19.0 21.75 440 270 665 1300 1630 48.0 295 780 1410 1820 52.0 320 890 1550 2000 550 345 975 1650 2140

0 2.0 22.0 32.00 75.0 550 1490 2400 3110 82.0 1670 2680 3470

0 Z5 25.0 43.75

10 3.0 28.0 5700

NOTE:

THE LETTERS B,C,D S M

UNDER SLOPE, REFERS TO THE

DRAINAGE RUNOFF CURVES.

FOR SELECTION OF PROPER

CURVE TO USE REFER TO

DRAWING NUMBER 3-L-14657,

FIGURE NO. 11.4

Compiled by:

SHERMAN, DEAN

TRUEBLOOD AND ROBISON

U.S. DEPT. OF AGRICULTURE

SOIL CONSERVATION SERVICE

REGION BE

MARCH 11,1952

3-L-27862
OPEN DITCH DESIGN1 TABLE FOR DITCHES WITH 4 to 1 SIDE SLOPES

DITCH SIZE ^^*^3^ .02% 04% 06% .08% .10% .15% .20%

Bottom

Width

Feet

Depth

in

Feet

Top

Width

Feet

Area

Square

Feet

"Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

C.f.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

c.f.a

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

C.f.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

c.fs.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

c.f.s.

WATERSHED HANDLED

BY DRAINAGE CURVES

B c D M B C D M B C D M B c D M B C D M B C D M B c^ D M

Q Ô.5 4.0 l.öö 0? 1 ? ? 2 0 3 P ? 4 4 0% P P 4 4 04 P s S 6 04 2 3 5 5 96 4 b / f o.t? 4 b / 7

0 1.0 8.0 400 1.3 a 10 15 15 !. S I! 14 2! ?? 13 17 26 ¿6 26 15 21 3i 31 2.9 17 25 35 35 3.5 21 42 42 41 24 33 49 49

0 1.5 12.0 9.00 4.0 ?4 32 48 48 50 30 40 61 6 1 70 4? 57 91 9! 80 48 66 107 107 90 54 75 124 130 10.0 60 85 140 153 12.0 72 105 \r6 206

0 16.00 8.0 48 66 107 107 12.0 72 105 176 206 14.0 83 125 212 272 160 95 146 250 360 18.0 460 23.0 137 227 455 700 155 268 575 840

0 2.5 20.0 25.00 150 89 135 231 315 21.0 l?5 ?Ô2 377 600 26 0 155 268 575 840 30 0 180 330 740 1035 33 0 200 385 880 1180 41.0 250 580 1180 149b 29 755 ia/b 1770

3.0 24 0 36.00 24.0 143 240 495 745 34.0 206 405 900 l??5 42 0 260 [JÍ0 1220 1540 49 0 300 RIO 1445 1870 54,0 335 940 1620 SIQQ 67, Q 460 l?99 210) 2719 575 1549 2499

-UT- 6.0 2.0Ô 0.5 T 6 07 4 6 1—r 09 5-1—r II ^-TT 1.0 6 —8-^ 7 9 13 13 1.4 "^8 N 17 17 1.6 10 19 19

2 0.0 6.00 ?? 13 17 ?6 26 31 IR 25 37 37 38 23 30 45 45 44 26 35 52 52 50 30 40 61 61 6! 36 49 7Î 70 42 57 91

2 1.5 4.0 5.6 33 44 70 70 79 47 65 106 106 97 58 82 136 146 II.O 66 95 158 178 12.0 72 105 176 206 15.0 89 135 231 315 18.0 107 460

20 80 20.00 II.0 66 95 158 178 16 0 95 146 250 360 190 113 179 319 510 220 131 214 415 650 25 0 149 254 30.0 180 330 740 1035 35.0 430

2 ^5 22.0 3( .00 19.0 1 13 179 319 510 270 161 ?B3 620 890 33,0 200 385 880 1 reo 38.0 230 500 1055 1360 430 265 640 1260 1585 52.0 320 890 1550 60.0 390 1120 1840 2370

2 3.0 42.00 300 180 330 10^55 4?0 260 610 1540 52 0 320 890 15^9 6O0 ^^Q ll?0 Ifí40 2370 fî70 460 1309 2100 2719 82.0 1 650 1679 ^689^ 94.0 855 1970 31/9 4110

4 0.5 3.00 08 6 7 13 1.4 1 1 ¡7 17 1.6 10 ' 13 19 19 11 14 21 21 2.2 13 17 26 2.6 1 5 21 31 31

4 1.0 12.0 i ;.00 3.1 1 8 25 37 37 3.8 23 30 45 5.4 32 43 67 67 63 38 51 80 80 7 0 42 57 91 91 8.5 50 70 11 6 11 8 lO.O 60 85 140 153

4 1.5 16.0 15.00 42 57 91 91 11.0 66 95 158 178 130 77 115 194 238 150 89 135 315 17 0 101 157 410 20.0 119 190 345 23 0 137 227 455 700

4 20 2^ .00 1' ,0 125 212 272 20.0 119 190 345 555 24.0 143 240 495 745 28.0 167 298 660 935 31.0 187 350 780 38.0 230 500 1055 1360 44.0 270 665 1300 1630

4 2.5 35.00 2; .0 137 227 455 700 33.0 200 385 880 1180 400 ¿46 555 1140 1450 470 290 755 1375 1770 520 320 890 1550 2000 64.0 430 1225 2000 74.0 535 14 0 3060

4 30 28.0 48.00 36.0 220 450 975 1280 500 910 93!? I4^p l??9 §'9 499 1145 71,0 500 1400 2260 2920 790 605 1590 2570 3310 97,9 90fJ 2050 4270 112.0 1170 2439 501 Û.

6 0.5 lO.C' ^.00 . 1 7 9 13 1 3 1.6 13 19 ^rr ^rt) 12 ""Te ^rr 13 •""nri 26 26 25 \5 '20 L 30 30 3.1 37 ^'37 3.6 21 29 43 « 3

6

14 (i 10.00 ^•.1 24 33 49 49 5 8 35 46 73 73 7? 43 59 83 50 69 1 2 114 93 56 78 129 137 II.O 66 95 158 178 13.0 77 115 194 2; 8

1 5 18.0 18.00 9.0 54 75 124 130 13.0 77 1 15 194 238 16.0 95 T46 360 I9.Ö 113 179 ^ 3 9 510 21.0 125 202 377 600 260 155 268 575 840 300 180 330 740 1035

6 2.0 22.0 28.00 17.0 101 157 271 410 24.0 143 240 495 745 290 173 314 985 34.0 206 405 900 1225 38 0 230 500 1055 1360 46 0 285 725 1340 1720 54.0 335

6 2.5 26.0 40.00 2ao 167 298 660 935 39.0 240 530 1100 1405 48.0 295 780 1410 1820 345 975 410 1175 1920 2460 760 560 1520 2450 3160 870 735 800 3740

6 3.0 30.0 54.00 41.0 250 580 1180 1495 58,0 375 1060 2270 72.0 510 1420 83.0 665 2730 3530 92 0 820 1920 3999 4000 113,9 1199 2460 3949 $140 1480 2949 6080

8 Ô.5 120 5 00 1.5 9 12 18 18 ¿1 12 17 25 2 5 15 20 17 35 35 33 39 39 40.0 24 32 48 48 27 36 55

8 1.0 16.0 12.00 5.2 31 41 64 64 73 43 60 95 8.9 53 74 122 128 100 60 140 153 12.0 72 105 176 206 140 83 125 212 272 160 95 146 360

8 1.5 20.0 21.00 II.O 66 95 158 178 16.0 95 146 360 20.0 119 190 555 220 131 214 415 650 25.0 149 254 535 795 187 350 780 1080 360 220 450 1280

8 24.0 32.00 20.0 119 190 555 28 0 167 298 660 935 35 0 213 430 940 1250 400 245 555 1140 1450 45.0 695 1320 1650 2140 640 430 1225 2569

8 2.5 28.0 45.00 32.0 193 365 11 30 45.0 280 695 1320 1675 55.0 345 1650 2140 64.0 430 1225 2560 72.0 510 1420 2960 870 735 1800 2890 3740 lOI.O 989 2150 4599

8 32 0 60.00 470 290 755 1375 1770 670 460 1300 2710 820 650 1670 2680 3470 94 0 855 m9 3170 41 10 1060 1065 3650 4760 129-9 1440 2899^ 4600^ §969 149.0 1789 3430 5430 7060

Ô 14 0 6 00 1.8 1 1 14 21 ¿1 25 15 —20^ 3(1 31 37 37 36 21 43 43 40 24 32 48 48 49 29 39 58 58 56 33 44 70 70

0 i.b 18.0 14.00 6i2 37 50 79 79 8.7 52 119 12; II.O 66 95 158 178 12.0 72 105 176 206 14,0 83 125 212 272 170 101 157 271 410 19.0 113 179 319 510

0 22.0 130 77 115 194 238 19.0 113 179 319 510 23 0 137 227 455 700 26.0 155 268 840 30.0 180 330 740 1035 360 220 450 975 1280 42.0 260 610 1229 (549

0 2.0 36.00 23.0 137 227 455 700 33.0 200 880 1180 4Q0 245 555 1140 1450 460 285 725 1340 1720 52,0 320 890 1550 2000 63.0 420 1200 1959 2520 73.0 520 1450 2330 3010

0 ^5 5000 370 225 475 1015 1320 52.0 320 890 1550 2000 63 0 420 1200 1950 2520 730 520 1450 2330 3010 82 0 650 1670 2680 3470 1000 960 2130 3400 4440 1160 1240 2540 4069 5290

0 3.0 ,_ K£l!Bii^sia &MÊm^fMfrll^fl Ih1-l«l K»W«1WßSMI^MflV^l*lí^üojtíiMfehia tK»lIEW>lEíHatW«I«llM*llbI*lF«:ítl|i{«.lEW*llII:l»^

DITCH SIZE ""^^ .25% .30% .35% .40% .45% . 50%

Bottom

Width

Feet

Depth

in

Feet

Top

Width

Feet

Area

Square

Feet

"Q"

tf.s.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

Cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

Cf. S.

WATERSHED HANDLED

BY DRAINAGE CURVES "0"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

B C D M B C D M B C D M B c D M B C D M B C D M

0.5 4.0 100 C.8 5 6 10 10 08 5 6 10 10 08 5 6 10 10 09 5 7 II II 1.0 6 8 1? 12 1.0 6 8 \t 12

1.0 8.0 4.00 ' JJ 27 36 55 55 5.0 30 40 61 61 54 67 58 35 46 73 73 62 37 SO 79 79 65 38 52 84 84

1.5 12.0 9.00 1^.0 83 125 212 272 15.0 89 135 231 315 160 95 146 250 360 170 101 157 271 410 18.0 107 168 293 460 190 113 179 319 510

0 160 1600 ¿ao 173 314 709 985 32.0 193 365 820 II3Ô 34.0 206 405 900 1225 370 225 475 1015 1320 390 240 530 1100 1405 41.0 250 580 11 8Ô 1495

0 20.0 25.00 53.0 330 915 1580 2059 sao 375 1060 1770 2270 630 420 1200 1950 2520

24.0 3600 860 720 1770 3680

2 0.5 1 1 14 19- "Ti -|5 ■■■23 - 23 2.1 12 "17 25 25 2,2 13 17 ' 26 26 2.4 14 19 29 29 2.5 IS 20 30 30

2 l.i 10.0 6.00 46 64 10- 8,6 51 71 117 121 92 55 77 127 135 9.9 59 84 139 153 II.O 62 89 149 164 11.0 66 95 158 'Í? 2 1. 14.0 12 00 200 119 190 555 22 0 131 214 415 650 23 0 137 227 455 7Ô0 25.0 149 254 535 795 270 161 283 620 890 28.0 167 298 660 936

2 2.0 18.0 20-00 390 240 530 1100 1405 43.0 265 640 1260 1585 460 285 725 1340 1720 49.0 300 810 1445 1870

2 2.5 22.0 670 460 1300 2710 74.0 535 1470 2370 3060

3.0 260 1050 3610 4710

¿ Ô.5 8.0 35 32 19 38 38 34 20 27 40 40 36 . 21 29 43 -3 38 23 30 45 45 4,1 24 33 49 49

t 1.0 12.0 lt.O 158 178 72 105 176 206 130 77 115 194 238 14.0 83 125 212 272 15.0 89 135 231 315 16.0 95 146 250 360

t 1.5 16.0 15.00 260 155 575 840 29.0 173 314 700 985 31.0 187 350 780 1080 33.0 200 385 880 1180 35.0 213 430 940 1250 370 225 475 1015 1320

i 2.0 20.0 24.00 49.0 300 810 1445 1870 54.0 335 940 1620 2100 59.0 380 1090 1800 2320

4 2.5 24.0 35.00 82.0 650 1670 2680 3470 ^ 3.0 ?§' é 05 1 0.0 4.Ô 24 32 4é 4Ô 4.4 26 3S S¿ 52 4.8 29 38 57 57 50 30 40 61 61 54 32 43 67 67 56 33 44 70 70

6 1.0 14.0 10.00 15.0 89 135 231 315 160 95 146 250 170 101 157 271 410 190 113 179 319 510 20.0 1 19 190 345 555 2L0 125 202 377 600

1.5 18.0 !?? 200 1180 360 220 450 975 1280 390 240 530 1150 1405 4^0 260 610 1220 1540 44.0 270 665 1300 1630 470 290 755 1375 1770

20 220 2800 éô.O 390 1120 1840 660 450 1280 2060 2660 71.0 5Ô0 1400 2260 2920

^ 26.0 40.00 970 905 2050 3280

3.0 3Q0 5400

05 12.0 5.00 5.1 30 40 62 62 5.7 34 45 "72 72 61 36 "48" 76 -76 65 38 52 84 84 69 41 56 90 90 73 43 60 95 95

16.0 12 00 18.0 107 168 299 460 18.0 1 19 190 345 555 21,0 125 202 393 630 23 0 137 455 700 24 0 143 240 495 745 260 155 268 575 840

1.5 200 21.00 400 245 555 1140 1450 43.0 265 640 1260 1585 47 0 290 755 1375 1770 500 310 835 1480 1920 530 330 915 1580 2050

20 24.0 32.00 71.0 500 1400 2920 78.0 590 1570 2520 3260

2.5 28.0 113.0 1199 2460 5140

3.0 32.0

0 0.5 14.0 64 38 52 82 82 69 41 56 90 90 75 46 63 102 102 8,0 48 66 107 107 as SO 70 116 118 9.0 54 75 124 130

10 1.0 18.0 1400 22.0 131 214 415 650 24.0 143 240 495 745 260 155 268 575 840 280 167 298 660 935 290 173 314 700 985 31.0 187 350 780 1080

10 1.5 22 0 2400 470 290 1375 1770 51 0 315 )65 1515 I960 550 345 975 1650 2140 590 380 1090 1800 2320

10 2.0 260 3600 82.0 650 2680 3470 90.0 790 1870 3000 3900 '

10 2.5 30 0 50.00 129.0 1440 4600 5980

'0 ^^ _ 39 54.9 66ÔO

NOTE:

THE LETTERS B,C,D S M

UNDER SLOPE, REFERS TO THE

DRAINAGE RUNOFF CURVES.

FOR SELECTION OF PROPER

CURVE TO USE REFER TO

DRAWING NUMBER 3-L-14657,

FIGURE NO. 11.4

Compiled by:

SHERMAN, DEAN

TRUEBLOOD AND ROBISON

U.S. DEPT. OF AGRICULTURE

SOIL CONSERVATION SERVICE

REGION m

MARCH 11,1952 \-i

H

I

ro

3-L-27863 LO
OPEN DITCH DESIGN TABLE FOR DITCHES WITH 8 to 1 SIDE. SLOPES

DITCH SIZE ^'^^ .02% .04% .06% .08% .10% .15% .20%

Bottom

Width

Feet

Depth

in

Feet

Top

Width

Feet

Areo

Square

Feet

"Q"

c.f.s.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

c.f.s.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

Cf. s

WATERSHED HANDLED

BY DRAINAGE CURVES

c.f.s.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

c.fs.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

"Q"

cf. s.

WATERSHED HANDLED

BY DRAINAGE CURVES

B C D M B c D M B C D . M B G D M B C D M B C D M B C D M

Q Ô.5 ¿"0 2 00 ? 3 5 5 06 4 5 7 7 Ö.7 4 6 8 8 Ö.8 6 6 10 IÓ 09 5 7 II II I.I 7 g 13 13 13 fí 10 15 15 Q 0 16,0 8 00 2.6 15 21 31 31 3.8 23 30 * 5 45 4.6 27 36 55 55 5.3 32 42 66 66 59 35 47 75 75 73 43 60 95 95 8.4 50 70 114 116

0 1,5 ?4,0 18 00 7.8 4; 64 104 104 II.O 66 95 158 178 13.0 77 115 194 238 160 95 146 250 360 170 101 157 271 410 21.0 125 202 377 600 25.0 795

0 2.0 320 3200 170 10 157 271 410 143 240 495 745 29.0 173 314 700 985 200 385 880 1180 370 225 475 1015 1320 46.0 725 1340 53.0 330 1580

0 2.5 5000 31.0 187 350 780 1080 43.0 265 121 ;o 1585 53.0 330 916 1580 2050 400 1145 680 470 1330 2760 83.0 665 1690 2730 3530 96.0 890 3250

0 ^q 720(1 VQ >4S > 1920 70' 490 2860 860 720 1770 29$Q 368Ç 940 2100 110,0 1155 2?90 ?9t0 i?ç.O "54? 3050 4840 629 I 156.0 1900 5720

3 10.0 300 6 1.0 6 i¿ l.á 7 § 14 14 * 8 1 1 17 17 1.6 10 13 19 1.9 1 15 23 2.2 t 3 26^

2 100 2 28 42 42 5.0 30 40 .1 61 6.1 36 49 78 70 42 57 91 91 79 47 65 106 106 9.7 5 1 82 136 146 11.0 66 158 178

2 1.5 21.00 57 80 132 142 13.0 77 115 |< 4 238 16.0 95 r46 360 19.0 113 179 3t9 510 21.0 125 202 377 260 15 268 575 30.0 180 740

2 36.00 19.0 ii; 179 3I< 51 28.< 167 298 660 935 34.0 206 405 1225 240 1100 1405 44.0 270 1300 1630 540 33 1620 2100 620 410 1920

2 55X0 35.0 21; 430 940 125 ' 8C 295 780 1410 j 1820 59.0 380 1090 2320 480 1350 2180 770 575 1540 94.0 85 1970 3170 4110 loao 1115 3770 4920

2 7800 :H1 975 IÇi*?? ?I4 i 77C 575 154 0 ?4<«? 3220 95.0 870 2000 4170 1135 2380 ?fil0 l??0 1340 2700 510 1810 î>SIO 7180 Ü 12- 2210 4100 6490

4 4.00 12 1.4 3 1 17 1.7 10 13 20 1 2 16 "^ 24 22 ' 13 17 26 26 28 17 33 33 '3.2 19 38 38

4 20.0 2.0 , 4 26 55 52 5 6.4 38 52 2 82 73 46 64 104 104 54 75 124 130 100 60 85 140 153 12.0 72 105 176 206 1' .0 83 125 212 2 '2

4 2' .0 1 .0 61 ; 95 158 16.0 95 i4( I 360 20.0 1 19 190 345 555 137 227 455 700 25.0 149 254 535 795 31.0 «87 350 780 1080 3.0 220 450 975 1280

4 , '_o) 22.0 13 214 415 (i5 ' 32.0 1130 39.0 240 530 MOO 1405 450 280 695 1320 1675 50.0 310 835 1480 1920 62.0 410 1175 1920 2460 7 .0 500 1400 2260 2920

4 6 0 > 2311 500 1055 !;>&> 550 l<>50 2I4Ô 670 460 1300 2100 2710 575 1540 2490 3220 860 720 1770 2850 3680 106.0 1065 2280 3650 4760 122.0 1340 27 lO 4310 5600

4

f??9 \, _ '1 ii?Q 1840 860 M*MlI«IMlI»M«lPJ*I«lttt¿«lCK*llMltlltW«aK*I.lCI4¿«ll.i.l*] ItWtJ lk£Mti«M*lE!:£M[:»:>1 ir*T»i !^*l^^i^«JtlM«l[çK*I*JUai^>lP^^^^

5' '1

6 1.0 22. i* .CO 33

3

44

II 'l7

68 61

17

7.7

1.9

6; 102 102

23

9.4

2.3

56

14

79

3

131

27

139

27

II.O

¿.7

66

16

95

21

158

32

178

32

12.0

3J i 72

18

105

24 36

150

3.7

135

té

231

44

315

44

17.0

47

iOt

25

157w 271 410

6 1.5 iO. 27.' i! 13.0 77 115 194 23 19.0 113 I7Í 510 230 137 227 700 155 268 575 840 29.' 173 314 36.0 450 1280 420 260 610 1220 1540

6 2.0 ;ao 44i i; 155 268 575 840 360 220 450 I2Ô0 440 270 665 I30Ô 1630 31 5 865 1515 I960 57.0 365 1030 1730 70 0 490 1370 2220 2860 80.0 620 1620 2600 3360

6 11 ' 6.0 65.00 143.0 265 640 1260 1585 60.0 390 1120 1840 2370 740 535 1470 2450 3060 850 700 1740 2800 3630 890 2020 3250 1170 1260 2570 4100 5360 135.0 1540 3050 4840 6290

6 3.0 54.0 mMefMusm CIi*l It'!*!*] >ÁI*>1 y^ii'i ^ummi4-mv^ïi»Mi'iki»itiu»Mnhii»ini:i*Mhi4i»Mii»yi»i\&u*ii^^^^ 1«;:K«1 "-r- 53 é.à 6.00 1.6 10 13 19 23 14 18 27 27 28 17 "22 Î 3 33 \<J 25 3.6 21 29 43 43 45 27 36 54 54 5.2 3-1 41 64 64

8 .0 40 1600 64 38 52 82 9.0 54 75 124 130 II.O 66 95 158 178 13.0 77 115 14.0 83 125 272 170 101 157 271 20.0 1 19 190 345 555

8 .5 ;2.Ô IÓ.UÓ 15.0 89 135 315 21.0 202 377 600 260 155 268 575 840 18C 330 1035 34.0 206 405 1225 250 1180 1495 4 70 290 1770

3 20 0.0 167 298 d36 40.0 245 555 1140 1450 49.0 300 810 14' 5 1870 365 1030 1730 63.0 420 1200 1950 78.0 590 1570 3260 < 0.0 790 3000 3900

8 2.5 8.0 7Q00 470 290 755 1375 1770 670 460 1300 2100 2710 82.0 650 1670 261 0 3470 870 2000 3200 4170 1050 1050 2250 3610 4710 129.0 1440 5980 1' 9.0 1780 5430 7060

3 m!sm mi^»ifMta'Ä»M »M ILMt] Ki+>] F+W«l |[»W(il I^I^M M|:T*] l^£l^L14.1*JIF4d*JI]tl;l!lF^i;I*Jt££I«Jl.l¿:i*Jl^^ I«:»>I«1KW:M ^9íli\ W.TO [:kW*l icr^.i

10 ( .5 "Tgö" 7.ÔÔ ¿.Ô ,2- lé ¿4 ¿4 ¿.è 17 ¿¿ 33 3S 3.4 20 27 40 40 3.9 23 31 46 46 44 26 35 52 52 5.4 32 43 67 67 6.2 37 50 J^ 79

10 .( 260 18.00 7.4 44 61 97 97 IQO 60 85 140 153 13.0 77 115 194 238 15.0 89 135 231 315 170 101 157 271 410 200 119 190 345 555 ??7 455 700

10 5 34.0 33.00 17.0 101 157 271 410 24.0 143 240 495 745 290 173 314 700 985 340 206 405 900 1225 380 230 1055 1360 470 29Ô 765 1375 1770 54.0 940 I6?0 2100

0 2.0 42.0 5200 31.0 187 350 7Ô0 1080 44.0 270 665 1300 1630 54.0 335 1620 2100 63.0 420 1200 1950 2520 70.0 490 1370 2220 2860 860 720 1770 3680 990 940 2100 3370 4380

0 25 50.0 75.00 520 320 890 1550 2000 73.0 520 1450 2330 3010 89.0 770 1850 2970 3840 103.0 1010 2200 3530 4600 115.0 1220 2510 4020 5240 141.0 1640 3210 6630 163.0 2030 3820 6030 7860

9 3,0 m^'Emii>a»r«iKiwi l-i^M ttííiílhW] W=1«J lli!£!lasM

H

I

ro

DITCH SIZE ' ^^^i^ .25% .30% .35% .40% .45% .50%

Bottom

Width

Feet

Depth

in

Feet

Top

Width

Feet

Areo

Squore

Feet

"Q"

Cf.S.

WATERSHED HANDLED

BY DRAINAGE CURVES

cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES

cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

cfs.

WATERSHED HANDLED

BY DRAINAGE CURVES "Q"

c f s.

WATERSHED HANDLED

BY DRAINAGE CURVES "0"

C f. s.

WATERSHED HANDLED

BY DRAINAGE CURVES

B C D M B C D M B G D M B C D M B c 0 M B c D M

0 0.5 f$ 2,00 1.5 Ô 12 1 18 1.6 10 3 Id Id 1.7 IÔ I* 20 §5 I.d II 15 23 23 20 12 16 24 ?4 21 12 17 ?6 ¿5

I.Ô léô é.ôô 9.3 66 78 12! 13 7 10.0 60 1 5 140 153 11.0 66 d6 158 L^l 12.0 72 102 171 199 13 0 75 10- 184 219 130 78 116 194 241

0 1.5 240 18.00 27.0 161 283 890 30.0 t80 l< 0 740 32.0 193 3!5 820 i'Aö ^§0 213 430 940 1250 37.0 225 475 1015 1320 39.0 240 530 1100 1405

0 20 32.00 596 1090 180 2320 650 440 12 5 2030 7Ô.0 490 1370 2220 2880 760 650 l490 2400 3110 79.0 605 1590 2560 3310

0 2.5 50.00 1070 1080 2300 4810 118.0 1275 2> )0 4140

0 3,0 72.00 174.0 4130 8560

2 05 3 00 ^1 15 ¡20 3Ó 27 16 21 32 32 2.9 17 23 35 35 3.2 19 25 38 38 34 20 27 40 40 3.5 21 28 42 42

1 1.0 IÔ.ÔÔ 13.Ô 77 115 238 140 83 125 212 272 15.0 89 135 25\ ?i5 16.0 95 146 250 360 170 101 157 271 410 lao 107 168 293 460

2 1 5 ¿6.0 ¿1.00 34.0 2Ô6 405 1225 370 225 475 1015 1320 400 245 555 1140 1460 43.0 265 640 1 260 1585 450 280 695 1320 1675 480 295 780 1410 1820

2 2.0 34.0 3600 690 480 1350 2180 2820 76.0 560 1520 2450 3160 82.0 650 1670 2680 3470 87.0 735 1800 2900 3720 930 840 1950 3130 4050

2 KM«a«.^.Ttll»ar.1ll;^r.1Mr^«T*lEMMI.i^«I*lll^i^f>] 1510 3000 JWg afeJM

? 30

4 0 5 1¿.0 4.ÔO 3.6 21 25 43 3Ô 23 31 46 46 4.2 2S 33 SO 6Ô 4.5 ¿7 36 54 54 48 29 38 57 57 50 30 4(' 61 61

4 1 0 20.0 12.00 16.0 95 146 360 170 101 157 271 410 19.0 113 179 319 510 20.0 119 190 345 555 21.0 125 202 3 7 600 220 131 2h 415

4 \.6 ¿aô 24.Ô0 40.0 245 555 1450 44.0 270 665 1300 1630 47 0 290 755 1375 1770 51.0 315 865 1515 i960 54.0 335 940 1620 2100 570 365 I03( 1730 '2230

4 2.0 360 40.00 80.0 620 1620 87.0 735 1800 2890 3740 940 855 1970 3170 4110 101.0 980 2150 3450 4500

4 25 440 6000 136.0 1560 3020 4880 6340 149.0 1780 3430 5430 7060

4 K-f-^!! Elî*l!] M1&M *I:W \&*i*] l+>I«] II«W«1

6 05 4Ô 5ÔÔ f-7 28 37 56 66 5.2 3l 4l f^ 64 56 33 44 70 70 60 36 48 76 76 63 38 51 80 80 67 40 54 86

6 1.0 14.00 lÄO 113 179 319 510 21.0 125 202 377 600 23.0 137 227 455 700 240 143 240 495 745 260 155 268 575 840 270 161 283 890

L5 2700 46.0 1720 5Lq 315 865 1515 I960 l^Si 345 975 1650 2140 590 380 1090 1800 2320 620 410 1175 1920 2460 660 450 1280 2660

3 2Ó 44(0 900 1870 3900 96.0 925 2080 3320 4330 IÔ6Ô IÔ66 2280 3650 4760 114.0 1205 2480 3940 5180

3 65(0 151.0 1810 3490 5530 7180 166.0 2080 3900 6170 8050

3 00.00 i

8 èôô 5,8 35 46 73 6.3 38 51 80 6.8 40 55 88 88 73 43 60 95 95 77 46 63 102 102 ai 48 67 109 109

8 1.0 24.0 16.00 ¿3.0 137 227 25.0 W9 254 535 795 270 161 283 890 2ao 167 298 660 935 30.0 180 330 740 1035 32.0 193 365 820 1130

8 1.5 3ÛIÔ0 53.0 915 2050 58.0 3'5 1060 2270 420 1200 1950 2520 670 460 1300 2100 ?710 71.0 500 1400 ??60 ?9?0 750 550 1490 2440 31IÖ

2.0 4aoo l( ( ,Ö 2130 4440 109.0 1115 2350 4920 119.0 1290 2620 4180 5450

8 2Ö 70.00 167.0 2100 3930 8120

8

îi 96.00

0 öS 41 56 90 ÔÔ 76 45 82 IÔI 101 a¿ 49 68 110 Il2 88 52 73 121 125 9.3 56 78 129 137 9 58 83 138 148

0 »P 18.00 260 155 268 575 29.0 173 314 985 31.0 187 350 780 1080 33.0 200 385 880 1180 3S.0 213 430 940 1250 37' 225 475 1015 1320

0 1.6 ; 4.0 33.00 éo.o 390 1120 1840 2370 660 450 1280 2660 71.0 500 1400 2260 2920 76.0 560 1470 2450 3160 81.0 635 1650 2640 3420 85 700 2800 3830

0 20 5200 III.O 1150 2410 3850 5030 122.0 1340 2700 5600 131.0 1480 2940 4680 6080

0 11 500 75.00 182.0 2380 4350 6900 9050

10 .30 68.Ô IÔ2.ÔO

NOTE:

THE LETTERS B,C,D a M

UNDER SLOPE, REFERS TO THE

DRAINAGE RUNOFF CURVES.

FOR SELECTION OF PROPER

CURVE TO USE REFER TO

DRAWING NUMBER 3-L-14657,

FIGURE NO. 11.4

Compiled by:

SHERMAN, DEAN

TRUEBLOOD AND ROBISON

U.S. DEPT. OF AGRICULTURE

SOIL CONSERVATION SERVICE

REGION Et —

MARCH 11,1952

3-L-27864
11-23b

I if soil conditions necessitate use of

-fl cut-off wall use o metol diaphragm

HE! NOTE'

Place 32" heavy woven wire fence on all

four sides. Fasten 2" x 4* guard rail to posts

over top strand of fence. Staple fence to

guard rail between posts.

The cross sectional area of the inlet must

be determined for each individual location.

In no case shall It be less than 2' square.

GroundJsiöfi*

MATERIALS FOR INLET

cu. yds. of concrete

bags of cement

_cu. yds. of gravel

cu. yds. of sand

4 6" top posts 6'long

32" woven wire fence

Use 4 sections of—'

Bell a Spigot sewer

tile with jointf cemented or encase 15'

of droin tile In concrete

CROSS SECTION OF INLET

COOPERATOB SEC.__ T

COOPERATIHS WITH -- 1 COUNTY STATE

1 'ADAPTED BYI OATE_ ..:::::"

REVISED 1-31-52

LOCATIONPIPE OUTLET FOR SURFACE WATER

PLAIN CONCRETE INLET

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

1. M. »CHNCTT, CMlEr

R.H. MUSSEg.DIWECTOB

^ GARTOSRAPHIC APPROVAL

p^ CHECKED

^ TECHNICAL APPROVAL

VB/J

- - - \m NUMKR

^9/s/ 3-L-17489 SHEET OF
11-2Í+

Ditch

Bottom

Ditch

Extend pipe to c

toe of slope or

0 flume or apron

point

l>eyond unless

Berm

Min. of 10' Min. 3:|

perpendicular to the

protected by

m:

Ditch Side

Spoil Bonk

Varies

Top Lend Side

If ice and floating debris are a

problem the corrugated pipe should

be placed at about a 30** angle

downstream instead of outletting

perpendicularly to the stream

PLAN

Protective Post

SECTION

^esleonitCut 2:| slope

ENLARGED SECTION OF INLET

CONSTRUCTION NOTE:

Where sod is to be used for

protection of inlet area, extend sod

at least 3 feet beyond slope on

all sides.

Select a good heavy sod

and lay by hand;

The orea should be frequently mowed to keep down weed

growth and maintain a good sod;

this is necessary to utilize full

capacity of pipe and maintain

the structure in operating condition.

"T6^ "V_^ U--^Ground Line-^ Li

COOPERATOft

COOPERATING WITH

_SEC. ^T R

COUNTY

ADAPTED BY

STATE.

ELEVATION OF INLET

LOCATIONCORRUGATED PIPE OUTLET

FOR SURFACE WATER

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

I. BENNETT, CHIEF

I. MUSSER. DIRECTOR

REFERENCE:

2û^r^.^L _- TECHj^lCAL APPROVAL

DESIGNED CHECKED

Vs/s,

DRAWING NUMBER

3-L-17487

FIGURE 11.7 CORRUGATED PIPE OUTLET FOR SURFACE WATER
11-25

Bottom of Open

Ditch

Berm

Min. of 10'

HI

Ditch Side

Sjio]j_Bcmç,

Min.-3 I

Jo^

Varies

:IE::

If ice and debris are a

problem the corrugated pipe

should be placed at about a

30*angle downstream instead

of outletting perpendicularly

to the stream.

Extend pipe to a point perpendicular

lo the toe of slope or beyond unless

protected by a flume or apron.

Land Side

Min.

PLAN

SECTION

NOTE:

Place 32" heavy woven wire fence

on all four sides. Fasten 2"x 4"guard

rail to posts over top strand of fence.

Staple fence to guard rail between posts.

MATERIALS FOR INLET

24" "T" branch bell & spigot vitrified

clay tile 4'-long with 15"spur

0.6cu.yds. of concrete

4 bags of cement

0.6 yds. of gravel

0.3 yds. of sand

4-6" top post 6' long.

l8'-32" heavy woven wire fence

Lumber

2-2"x 12" X 4'-6" planks

2 - 2" X 4" X 4'- 6"

2 - 2" X 4" X 4'- 9"

Necessary staples and spikes or bolts.

COOPERATOR _SEC T_ . R

C00PERAT(N6 WITH

COUNTY STATE.

ADAPTED BY _ DATE

PIPE OUTLET FOR SURFACE WATER

SEWER TILE INLET

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT, CHIEF

R. H. MUSSER. DIRECTOR

>RTOGRAPHIC APPROVAL .^ TECHNJCi

Location

CHECKED DRAWING NUMBER

'/9M 3-L-17490

FIGURE II.8
11-26

11.55 Ditch Layout and Construction

a. General

Construction should not be started, whether to be done by contractor or cooperator, until details of the plans and specifications are discussed and understood by both the cooperator and

contractor. This is important. Generally the most economical

and best adapted equipment for open ditch construction is a

dragline. In the method of layout as described below it is

assumed a dragline will be used.

b. Ditch Layout

Centerline stakes and slope stakes set at 100 foot intervals

along the ditch are usually sufficient. Determine depth of cut

from ground level at one of the slope stakes (at each station)

and mark it on this slope stake. (See Part 1.52c for procedure

in setting slope stakes.) Place a reference stake offset k to

6 feet outside of slope stake and on the opposite side from

where spoil is to be placed. This stake is sometimes used to

check grade and ditch alignment behind the dragline; when used,

these are generally set at each station.

c. Checking Construction

All construction should be carefully checked as work progresses

and faulty work or work that does not meet specifications should

be corrected while the equipment is reasonably close. The final

check and approval should be made before the equipment leaves

the job. The work should be checked for the following, plus any

other specification requirements:

(1) Conformance of ditch grade to the designed grade.

(2) Conformance of ditch bottom width to designed bottom

width.

(3) Conformance of side slopes and berms to designed side

slopes and berms.

(k) Conformance of spoil spreading to specifications.

(5) Conformance of pipe outlet installations for tile

drains to specifications.

(6) Conformance of pipe inlet installations for surface

water to specifications.

(7) Conformance of open lateral surface drain installations

to specifications.
11-27

11.56 Ditch Maintenance

a. Ditchbanks and channels should be kept clean of shrubs and

trees. If silt bars or sand bars occur in the channel^ they

should be removed. Sod on ditchbanks is necessary for effective

maintenance. It serves to control washing of the soil as well

as to retard the growth of weeds and willows. Expensive seedbed

preparation and seeding of ditchbanks are desirable but only insofar as the banks will retain and germinate the seed. The seeding should extend from the water level in the ditch to at least

the ridge of the spoil bank. If there is no spoil bank the distance should be at least one rod from the top of the ditch.

Little work may be possible on the ditchbanks, especially if

they are steeper than 2:1, but the berm and spoil bank should be

properly prepared for seeding. When well vegetated the seed

from this area generally will spread to the ditchbanks. Seeding

recommendations in local Technical Guides should be followed in

establishing vegetation. Woody growth of various kinds usually

sprout easily on new ditchbanks. It is a good idea to remove

this young growth by spraying or hand cutting if necessary.

After establishing a good sod it is necessary to control weeds

and woody growth by pasturing, mowing, or spraying. Slopes 3:1

or flatter are considered necessary for successful use of mowing

equipment. The pasturing of ditches is effective if properly

controlled. Stock should be kept off ditchbanks following

freezing spells or periods of heavy rainfall. Ditches must not

be overgrazed. HOGS SHOULD BE KEPT OUT OF DITCHES AT ALL TIMES.

b. Ditch rights-of-way provide an ideal habitat for wildlife if

properly managed. Mowing should not be done, nor pasturing

allowed, until after grain harvest, so that ground-nesting birds

will have a chance to get off the nest. (Eefer to Regional

Biology Handbook for "Wildlife Management of Ditches and Odd

Areas.") An electric fence will facilitate control of pasturing.

11.60 SURFACE DRAINAGE

11.61 General

a. Surface Drainage Defined

Surface drainage, as the name implies, is the removal of surplus

water from the surface of agricultural land. The purpose is to

rid land quickly of its excess water and thereby prevent soil

from becoming too wet.

b. Conditions Under Which Surface Drainage is Applicable

This system of drainage is applicable under certain soil and

other conditions as follows:

(1) Very slowly permeable soils such as heavy clay or gumbo.

(2) Shallow soils (9~20 inches) with underlying very slowly

permeable subsoils.

259293 O - 53 - 14
11-28

(3) Soils that need and are responsive to tile drainage but

where no outlet for tile can be made available.

(k) Areas that are not economically feasible to tile drain.

(5) As a supplement to tile drainage.

c. Types of Surface Drainage Systems

(1) There are essentially five types of surface drainage

systems in common usage.

(a) Bedding system,

(b) Random ditch system.

(c) Field ditch system for water table control and surface water removal.

(d) Cross slope ditch system (similar to drainage type

terraces).

(e) Parallel ditch system.

(2) These various systems are described in detail in Part

11.65.

d. Procedure to follow in establishing surface drainage:

(1) The installation of surface drainage systems is similar

to the execution of any other engineering project. The following essential steps are discussed in the paragraphs below:

(a) Gathering essential field information and making

an engineering survey.

(b) Preparation of the topographic map.

(c) Arrangement and design of the system.

(d) Construction.

(e) Maintenance

11.62 Gathering Field Information and Survey Data Needed For Design

of Surface Drainage Systems

a. General

Before starting to make a final survey the technician should

have made a preliminary inspection of the area in accordance with

the general procedures outlined in Part 11.30 above. As a

result of this preliminary inspection a decision should have

already been reached on the nature of the problem, the type of
11-29

surface drainage system to be used^ and the availability and location of a suitable outlet. With these pre)liininary decisions

already reached the next step is to gather the essential field

information and survey data needed to plan the surface drainage

system. The amount of information will vary with the individual

field and the system to be used.

b. Topographic Information Required

Topographic infonnation of the area to be drained is necessary

except on fields with sufficient slope so that the general lay

of the land is obvious by eye. This information especially is

necessary for determining the direction of bedding furrows^ the

location of field surface ditches, and other details in planning.

Mistakes in the layout are commonly found, especially in planning bedding systems, and many times the beds run the opposite

direction to that required for best drainage. These mistakes

can be avoided if proper topographic information is obtained.

Some details to observe in obtaining topography are:

(1) The grid system, described in Part 1.^3 is the most

simple method of obtaining topographic information. However,

other methods may be used if suitable equipment is available

which local technicians are trained to use.

(2) On flat land, obtain elevations at 100 foot to 300 foot

horizontal intervals depending on how nearly level the land

is and whether or not the drainage pattern is apparent from

inspection. Locate all low or depressional areas and take

additional elevations of them as a part of the survey. The

flatter the land the more important it is to take elevations

at relatively close intervals.

(3) On depressional type topography where random surface

drains are to be used, vary the amount of survey data according to ground conditions. In cases where depressional areas

are numerous, elevations at close intervals will be necessary,

whereas in areas with few depressions a skeleton topographic

map may suffice. In either case the survey should be in

sufficient detail to locate and determine elevations of

depressional areas and the low point of the divide between

depressional areas.

(h) Physical features of adjacent land affecting the surface drainage of the proposed area should be obtained.

Especially obtain the location, elevations, and information

of: all ditch bottoms or drainageways, size of opening and

flow line elevations of culverts and bridges, or any other

similar information necessary to plan the drainage system.

(5) Unless the outlet ditch is obviously adequate it will

be necessary to run a profile and cross section survey of

the ditch line to determine if it has sufficient grade and

capacity to serve as an outlet (see Part 1.37 fo^:' details of

profile and cross section surveys).
11-30

11.63 Preparation of Topographic Map

General instructions for preparation of data sheets outlined in

Part 2 should be followed in making the topographic map. The

following suggestions are applicable especially to surface drainage systems.

a. Use standard size drawing paper, preferably plan-profile

paper when available. When the area is too large to get the location plan on the unruled part of plan-profile paper at the

proper scale, use standard plain drawing paper for the location

plan. Then use full size profile paper for plotting profile.

b. The minimum scale of the topographic map will depend on the

frequency of elevation shots. Some judgment should be exercised

in choosing an appropriate scale. For most bedding furrow

systems the minimum scale should be 200 feet per inch; but for

a random surface drainage system with scattered depressional

areas, a scale of 300 or ^00 feet per inch may be satisfactory.

It might even be possible to plot elevations on an aerial photo

(660 feet = 1 inch, or kkO feet = 1 inch).

c. Show the location and elevation of bench marks, existing

outlet ditches, survey base lines, field divisions, roads, and

other physical information.

d. Contour lines are generally needed in planning the arrangement of surface drains, but many times on very flat land it is

not practical to draw them in. In such cases it is better to

plot the location and elevation of survey shots on the map and

do the detail planning of the surface drainage system directly

from the plotted elevations.

11.6^ Basic Steps in Planning and Design of Surface Drainage Systems

The planning and design of surface drainage systems may be

divided into the following basic steps:

a. Arrangements and Design of the Surface Drainage System

This involves a study of the topographic map and the development

of a plan showing the arrangement of the surface drains and the

location of the field ditches and the location of the outlet

ditch. Detailed information on arrangement and design of various surface drainage systems is given in Part 11.65.

b. Design of Field Ditches

The field ditches that remove the water from the shallow field

drains require individual and special design. A detailed discussion on the design of field ditches is given in Part 11.66.
11-31

Design of Outlet Ditches

The outlet ditch draining the entire system is essential for

proper function of surface drainage. A suitable outlet either

must be available or a special design must be prepared. Outlets

for surface drainage are similar to all other open ditch design

for drainage purposes. This subject is covered in detail in

Part 11.40.

11.65 Tiie Arrangement and Design of the Surface Drainage System

a. General

Brief descriptions and detailed specifications for the various

types of surface drainage systems are given below. Using the

topographic map (described in Part 11.63) as a base map^ the

system to be used should be planned in accordance with these

specifications. It is recognized that the planning of surface

drainage must be adapted to local conditions and, therefore,

some deviation from specifications may be necessary.

b. Arrangement and Design of Bedding System

(1) Description and General Application

This system of surface drainage is generally used on land

with flat slopes (0-l-|^) where the soils are slowly permeable

and where tile drainage is not economically feasible. The

system is designed, constructed, and maintained so that

excess surface water drains laterally from beds similar to

plow lands into the dead furrows, thence into the collection

ditches and finally into an outlet ditch. Figure 11.9, page

11-32. The planning of the bedding system should be given

careful consideration and an understanding reached with the

cooperator on the layout to be used. Improper understanding

of the layout by the farmer and lack of planning have been

the major causes of failures. A typical plan of a bedding

system is shown in Figure 11.10, page 11-33.

(2) Factors Affecting the Width of Beds

The following conditions should be considered in determining

bed widths:

(a) Kind of crops to be grown. Some permanent pasture

or hay crops do not require as narrow beds as general

rotation crops.

(b) On land that has numerous shallow depressional

areas land smoothing should be done before bed widths

are considered.

(c) Slope of field. Flatter fields require narrower

beds.
11-32

COLLECTION DITCH

THE FURROWS DRAIN TO COLLECTION

DITCHES. PLANTING, SEEDING AND

CULTIVATING CAN BE IN EITHER

DIRECTION. GENERALLY GRAIN CROPS

THAT MATURE EARLY SHOULD BE

WORKED ACROSS THE FURROWS AND

ROW CROPS THAT MATURE LATE

SHOULD BE PLANTED PARALLEL.

WIDTH OF BEDS FOR

GENERAL FIELD CROPS

DEGREE OF

INTERNAL

DRAINAGE

OF THE SOIL

WIDTH OF

BED IN FEET

CENTER TO

CENTER OF

DEAD FURROWS

NO OF SVz'

CORN ROWS

WITH 2'

ALLOWED

PER DEAD

FURROW

NO OF

ROUNDS

USING

2- 14"

PLOWS

VERY SLOW

23 6 5

30 8 6'/2

37 10 6

SLOW

44 12 9'/E

51 14 II

FAIR

58 16 \Z\

65 18 14

72 20 \^\

79 22 17

86 24 IS'/i

93 26 20

OUTLET DITCH SHOULD BE AT LEAST

0.5' TO 1.0* DEEPER THAN COLLECTION

DITCH. THIS WILL PROVIDE COMPLETE

DRAINAGE OF COLLECTION DITCH SO IT

CAN BE CROSSED WITH FARM MACHINERY.

N SOILS SUBJECT TO SEVERE EROSION

THE OVERFALL SHOULD BE GRADED BACK

ON A NON-EROSIVE GRADE.

THE U-SHAPED SECTION IN THE BOTTOM OF THE DITCH

IS OPTIONAL. IT PERMITS MAIN PART OF DITCH TO DRY

QUICKLY SO THAT TRACTORS CAN PASS OVER EVEN THOUGH

END OF FIELD THE BOTTOM OF THE U-SECTION IS WET.

MIN DITCH CROSS

SECTION 5 SO FT

:T.^.yjg>!^^i-'4i^^fe^'^-^^^^^^^

DEAD

FURROW

- DIRECTION OF BEDDING

CROSS SECTION AT END OF FIELD SHOWING COLLECTION DITCH AND TURN STRIP

DEAD FURROWS MUST HAVE A

CONTINUOUS GRADE WITHOUT

ANY OBSTRUCTIONS THAT MIGHT

INTERFERE WITH THE FLOW OF WATER

CROWN HEIGHT 5 TO 8

CONTINUOUS UNIFORM SLOPE FROM CENTER OF BED TO DEAD FURROW

— WIDTH OF BED

IXJ DEAD FURROW

5" TO 8" DEEP

CROSS SECTION OF BED SHOWING CROWN EFFECT AND PROPER SPACING OF CORN ROWS

FIGURE 11.9 SURFACE DRAINAGE BEDDING
11-33

Dead furroti/s /o be s/joced ^SO'ofar/-

in direcfion shoiA/n.

P/an^- ron/^ cro/ss /n d¡reef/on o/" furroa^s,

and ^rain crojaa perpendicular fo furroM'S.

^^ ^"^^"^ -^ - ~'<, • ^ Spo// ' *,i Sank "t_

"5p '~^ rurno^'sZ-r/p 'Jsf'dnd Fieldii*h>od ^'

Top of /'rod O. e'aboi/e

^^ ground in norfh properly line

^' ^ fence 40O'£.031-of corner post

i

ofSfarD.D, R/lf.

£/ey. 99.3S

LOC/IT/O/V/ WfíTERSHEP M/lf>

Se* af9fct///o/er/r far «fre//r«y«

4éo' laeo' i9ao' aè4o'

3tor TIMO, T86N-RI0E

Lucky Co. - S fate

Drainage ñrea * 136 /lares

Soil Type - Oroup /7

*w ¿arid Use - Cu/ri^rafed

Jy Average Rofafion-C-3m.6r.-N.M.

LOC/RT/Û/V Pl^AN Fo/P 3Tf^UCTUR£

L-00000

FIGURE 11.10 SAMPLE DATA SHEET BEDDING SYSTEM OF SURFACE DRAINAGE
11-3^

(d) Drainage characteristics of the soil. Soils with

low infiltration and permeability rates require closer

bedding.

(3) Eecommended Bed Widths

(a) The bed widths specified in Figure 11.9 may be

used as a general guide. They should be supplemented by

local experience, as reflected in local Technical

Guides. When the bed width has been determined make

minor adjustments so that the width is adaptable to

farming operations. It is usually unprofitable to grow

row crops in dead furrows, thus bed widths should be

adjusted so that the rows will fit the beds without

unnecessary waste of ground along dead furrows or

crowding rows too close to dead furrows. See Figure

11.9, page 11-32 and Figure 11.22, page 11-59 for

details of laying out beds. Bed widths should be

adjusted so that the width is a multiple of one through

or one round with the plow. Size of plow will govern.

For example: a two-bottom 1^1--inch plow, when properly

set and operated, will plow a width 28 inches per

through and 13 throughs or 6^ rounds will cover a 30-

foot width. Likewise, l6 throughs or 8 rounds will

cover a 37-foot width, etc. Time will be saved when

beds are spaced to fit the plow.

(k) Direction of Beds

The beds should be laid out with the dead furrows running in

the direction of greatest slope. Collection ditches are

laid out in the direction of lessor slope because they can

be graded. When land slopes are steeper than l|^, drainage

type terraces should be used, see Part 11.65e, page 11-^2.

(5) Location of Collection Ditches

Collection ditches are the field drains that carry the surplus water from the bedding furrows. Some of the important

features in location of these ditches are:

(a) The spacing of collection ditches should be at

regular intervals depending upon land slope and imperviousness of the soil. On flat slopes (0.1^) with very

slow permeability the spacing should be about 300 feet.

This may be increased to 1,000 feet for more sloping

land with fair permeability.

(b) Where collection ditches are placed at the end of

fields allow a turn strip between the ditch and the end

of the field as shown in Figiire 11.9. This is necessary

so that the dead furrow can be plowed out all the way to

the collection ditch.
11-35

(c) Where there are natural low spots in the field

that are not smoothed out, collection ditches should

follow these depressions similar to that used in the

random ditch system. See example Figure 11.11, page

11-36.

(d) Where it is necessary to drain water into collection ditches and the spoil cannot be disposed of without obstructing the drainage into the ditch, use a

double ditch (commonly referred to as a "W" ditch).

See Part 11.66e for further details on this type of

ditch.

(6) Design of Collection Ditches

The design of collection ditches is essentially the same as

for all field ditches for surface water removal. Refer to

Part 11.66 for design details.

c. Arrangement and Design of Random Ditch System

(1) General Description

This system, which is generally used on depressional type

topography, consists of a lateral outlet ditch and surface

drains extending into the wet "pockets" or depressions. The

surface drains meander from one depression to the other

flowing toward the lateral outlet ditch. Figure 11.12, page

11-37. It is necessary many times to combine this system

with the bedding system to do an adequate Job of surface

drainage. Figure 11.11. Sometimes on high value land, tile

drainage also is used in conjunction with the random system.

(2) Location of Random Ditches

No exact criteria can be laid down for the planning of random ditch systems. Since this type of drainage is used on

depressional topography the location of the ditches must be

run at random through the low spots andof sufficient size

and depth to drain them. Usually the ditches will be located in cultivated fields. Where they are not too deep

they may be crossed in farming operations but some ditches

draining deep pockets obviously cannot be crossed. A typical plan of a random ditch system of surface drainage drawn

on a standard data sheet is shown in Figure 11.13, page

11-38 and 11-39.

(3) Design of Random Ditches

Design of random ditches is similar to all field ditches for

surface water removal, as described in Part 11.66.
33m

y

LO

ON

OOzmD

CDmogzo>

33>OOoI

-<

encomo>o

From Stencil Circular 230 by courtesy of Extension Service

College of Agriculture, Madison, Wisconsin
11-37

REMOVE MINOR DEPRESSIONS BY LAND SMOOTHING WITH LAND PLANE OR LEVELER

SMOOTH AREA SO LAND WILL DRAIN TO THE LARGE DEPRESSIONS OR RANDOM DITCHES

:^

DEPRESSIONS WHERE

RUNOFF COLLECTS

WASTE SPOIL IN LOW SPOTS

OUTLET DITCH SHOULD BE

0.5' TO r DEEPER THAN THE

RANDOM FIELD DITCHES.

THIS WILL PROVIDE COMPLETE

DRAINAGE FOR RANDOM DITCHES

SO THEY CAN BE CROSSED WITH

FARM MACHINERY. ON SOILS

SUBJECT TO SEVERE EROSION

THE OVERFALL SHOULD BE

GRADED BACK ON A NON-EROSIVE

GRADE

SHALLOW RANDOM FIELD DITCHES

^^-'

>'

X^^

GRADE BACK SMALL OVERFALLS ON A

NON-EROSIVE GRADE. WHERE THIS ISNV

POSSIBLE USE A CHUTE, DROP SPILLWAY

OR PIPE.

CROSS SECTION OF RANDOM DITCH

CROSS-SECTIONAL AREA SHOULD BE DESIGNED FOR NOT LESS

THAN APPLICABLE DRAINAGE RUNOFF 8 NEVER LESS THAN 5 SO. FT.

MIN. SIDE SLOPE OF 41 WHERE

FARMING OPERATIONS ARE

PARALLEL TO DITCH AND 81 OR

FLATTER WHERE THE FARMING

OPERATIONS CROSS THE DITCH.

MOVE SPOIL TO DEPRESSIONS.

IF THIS IS NOT POSSIBLE USE A

DOUBLE DITCH WITH SPOIL PLACED

BETWEEN DITCHES.

..-'y^3l«C3::âit'K:='^rr^

MIN. DEPTH 9"

FIGURE 11.12 RANDOM DITCH SYSTEM OF SURFACE DRAINAGE
H

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USE THIS SHEET FOR MINOR JOBS ONLY Order blank form by Orowing No. 3-N-2
EARTH WORK COMPUTATIONS

DESIGN AND SPECIFICATIONS ,,

inches in 24 hours. lbi_

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f////'n^ Sfrta// depr^ss/'ory oc¿/acen^ fo

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so o9 no^ -f-o /nferfare »v///^ f/oitv ofsurface

wo^er yn^o /ha cf/Z-chas.

OITCH

CONSTRUCTION REPORT

LENGTH CUBIC YARDS COST

A ZQpg!_ _

. _ -JPi^i- Z-

&7^U 3MiA

' DATE

Sh.

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/04.3

/05.0 /02.0

/05.Z /oe.0Z5

/04.0 (0t075

¡040

/040

/04&

/05 2

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/04'.4

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/04i

/04.3

/05.H

4.^3 yos.oi

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/OZ.4C

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2.35

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3/7.5

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238

2.32

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¿40

0.90

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32. G

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TOTAL. , -op Dire / A

GS2

80. G

/O/S

773

24.0

20.2

32.G

G3.0

GG.2

50.3

30.4

20.2

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G.9

43.0

44 2

52.8

35.G

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6/3

30G

33.G

20.3

A/oTs: : ypra/opi? ChorFßy ^umof^nc/ifl/'^GS

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34

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82

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233

217

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38

/322

TOTAL CUBIC YARDS 4-733

S.C Ser\//ca

COOPERATOR

urop/a

' r.fMlWTV

S/on/r

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

SHEET_^0F.2_ DRAWING NO. 3-N-QOOQQ

Order blank form by Drawing No. 3-N-Z68e9

H

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11-tó

d. Arrangement and Design of Field Ditch System for Water Table

Control and Surface Water Removal

(1) Description and general application:

This system of surface drainage consists of field ditches

laid out in a regular parallel pattern across the field.

The function of the ditches is to lower the water table sufficiently for crop production and to collect and remove surface water from the field, Figure 11.1^, page 11-41. Ditches,

for this purpose are used under conditions where lowering of

the water table is necessary but where the use of tile is

not economically or physically feasible. The following are

some typical soil conditions where these ditches are used:

(a) On peat and muck soils where tiling is not applicable,

(b) On sands with high water table,

(c) On moderately or highly permeable mineral soils

which have a high water table. Sometimes these soils

are underlain with a water-bearing sand.

(2) Design specifications:

(a) The ditches are laid out parallel, across the

field at depth and spacings for various soil conditions

as follows :

MIKIMUM SPECIFICATIONS FOR FIELD DITCHES FOR WATER

TABLE CONTROL UNDER VARYING SOIL CONDITIONS

Ditch Mineral Soils Organic

Specifications Sand Except Sand Soils

Depth k ft. 2.5 ft. 3.0 ft.

Bottom width ^ ft. 1 ft. 1 ft.

Side slopes 1:1 1^:1 Vertical

Max. spacing 660 ft. 33O ft, 200 ft.

(b) The spoil should be used to fill depressional

areas between ditches or spread sufficiently to allow

the area next to the ditch to be used for turn rows or

permit cultivation.

(c) Crop rows, dead furrows, and plow furrows should

be intercepted in shallow ditches and directed into

field ditches through protected overfalls.
11-41

MAXIMUM SPACING OF

PARALLEL FIELD DITCHES

ORGANIC SOILS

CROP ROWS, DEAD FURROWS AND PLOW

FURROWS SHOULD BE INTERCEPTED

BY SHALLOW DITCHES AND DIRECTED

INTO THE FIELD DITCHES THROUGH

PROTECTED OVERFALLS.

(EXCEPT SANDS) (PEAT 6. M U CK)

SPREAD SPOIL FROM DITCHES IN

DEPRESSIONS OR UNIFORMLY OVER

THE FIELD. REMOVE ALL HUMPS AND

BACK FURROWS BY LAND SMOOTHING

OR GRADING SO THAT SURFACE WATER

FLOWS TO DITCH UNOBSTRUCTED.

MIN. SLOPE VERTICAL

FOR RAW PEAT AND 11

FOR DECOMPOSED PEAT

AND MUCK.

TYPICAL MINIMUM DITCH CROSS SECTIONS

MIN. SLOPE OF \Vz- \

2.5' MIN. DEPTH

I MIN

ORGANIC SOILS

(PEAT a MUCK)

MIN. SLOPE OF 1:1

\

\ 4.0' MIN. DEPTH \

'"-' '" ', •".ii

' - L ''''"'* J ff n .

MINERAL SOILS

EXCEPT SANDS

SANDS

FIGURE 11.14 FIELD DITCH SYSTEM FOR WATER TABLE CONTROL AND SURFACE WATER REMOVAL
11-42

e. Arrangement and Design of Cross Slope Ditches (drainage type

terrace)

(1) Description and Application

This type of surface drainage resembles terracing in that the

drainage ditches follow around the slope on a uniform grade

according to the lay of the land. For this reason they have

been called cross-slope ditches. Figure 11.15, page 11--43.

This method has application on sloping wet fields, four percent or less, where internal drainage is poor from the plow

sole downward and where many shallow field depressions hold

water after rains.

(2) Design Specifications

(a) Ditch alignment. Across slope as straight as

topography permits and with limited cuttings through

ridges and humps.

(b) Spacing. One hundred feet on k percent slope,

increasing to 150 feet as the slope decreases to 0.5

percent.

(c) Depth and cross section. Design the channel to

carry 10-year frequency rain but minimiim cross section

should be not less than 6 square feet. Minimum depth

should be 6 inches for trapezoidal section with 6 feet

bottom and 8:1 side slopes. For V section the minimum

depth should be 9 inches with 10:1 side slopes.

(d) Spoil. Excavated material should be placed in

.depressional areas between ditches. Excess material

shall be spread to a maximxim height of 3 inches on the

downhill side of the ditch.

(e) Land smoothing. Area between ditches should be

smoothed or graded after depressions have been filled

to eliminate all surface basins and humps that will

obstruct the free flow of surface water.

f. Arrangement and Planning of Parallel Ditch System

(1) Description and Application

The "parallel ditch system" is adapted to flat, poorly

drained soils in which there are numerous shallow depressions.

Quite often in the past bedding has been used under these

conditions but this may be eliminated if the field is smoothed

or graded so there is uninterrupted crop row drainage to the

parallel field ditches.

The field ditches should be parallel but not necessarily

equidistant. The success of the system depends largely upon
ll.ii3

SPACE CROSS SLOPE DITCHES lOO' APART

ON 4% SLOPE INCREASING TO I50' AS THE

SLOPE DECREASES TO 0.5%

CROSS SLOPE DITCHES SHOULD

BE CONSTRUCTED ACROSS THE

SLOPE AS STRAIGHT S PARALLEL

AS THE TOPOGRAPHY PERMITS

WITH LIMITED CUTTING THROUGH

RIDGES AND HUMPS.

AFTER THE DITCHES HAVE BEEN

CONSTRUCTED SMOOTH OR GRADE

THE AREA BETWEEN THE DITCHES.

THIS WILL ELIMINATE ALL THE MINOR

DEPRESSIONS AND HUMPS THAT OBSTRUCT

THE FREE FLOW OF SURFACE WATER TO

THE CROSS SLOPE DITCHES.

LATERAL OUTLET DITCH SHOULD

GENERALLY BE VEGETATED.

TYPICAL FLAT BOTTOM SECTION

FILL DEPRESSIONS WITH MATERIAL

EXCAVATED FROM DITCH

SPREAD OUT EXCESS EXCAVATED MATERIAL

HERE SO THAT RIDGE IS NOT OVER 3 INCHES

ABOVE NATURAL GROUND LEVEL

TYPICAL V-CHANNEL SECTION

S&SFes""*,': i^ATURAL GROUND^ LEVJL

N. DEPTH

FIGURE 11.15 CROSS SLOPE DITCH SYSTEM OF SURFACE DRAINAGE-TERRACE TYPE DRAINAGE

259293 O - 53 - 15
11-i^if

the spacing of the parallel ditches and the smoothing or

grading between ditches.

(2) Design Specifications

Design of this system must be adapted to the individual field

using a few general principles. The ditches must be spaced

so that the length of row drainage from a high point to a

field djtch is such that the row can safely carry the runoff

without much overflow or erosion in the row. Another factor

influencing ditch spacing is the amount of earth and the

distance it will have to be moved to provide complete row

drainage. î^igure 11.16, page 11-^5.

Field experience indicates that the maximum length of grade

draining to a given ditch should be about 600 feet. This

maximum length of grade should be reduced on slowly permeable,

highly erodible soils to about 300 feet. Therefore, the

maxim\im spacing where the land drains in one direction should

be about 600 feet. If the topography is such that the land

will drain from a ridge located between the ditches, the

maximum spacing could then be 1,200 feet.

When the ground surface has some general slope in one direction, the area between ditches can be smoothed, thus filling

the depressions and removing barriers. It is not necessary

that the slope be uniform between ditches. It can be broken

according to the lay of the land.

On areas where the ground surface has little or no general

slope, a grade must be established between ditches by cutting on one side of the field and filling on the other side.

Minimum dimensions of the parallel ditches are given in

Figure 11.16, page 11-^5-

11.66 Design of Field Ditches

a. General

(1) The term "field ditches" is used to designate the part

of the surface drainage system that collects surplus water

from the field drain and conveys it to an outlet ditch.

These ditches have been variously named collection ditches,

interception ditches, and random ditches, depending on the

type of surface drainage. However, the fundamentals'of

design and construction are the same.

(2) The location of the proposed field ditches was determined in planning the surface drainage system. Therefore,

the remaining work to be done is to design the ditches for

construction.

The purpose of this part of the handbook is to discuss design

criteria of these various field ditches.
11-45

PARALLEL DITCHES TO INTERCEPT AND RAPIDLY REMOVE SURFACE WATER

FROM THE FIELD AND REDUCE THE LENGTH OF ROW DRAINAGE

ROWS CONTINUOUS ACROSS

FIELD. DO NOT PLANT IN THE

- DITCH BOTTOM. CLEAN OUT

DITCH BOTTOM WITH PLOW

SHOVEL OR V-DRAG AFTER

EACH FARMING OPERATION.

T:t;-^£

DITCHES SHOULD BE

PARALLEL BUT NOT

NECESSARILY EQUIDISTANT

SPACING DEPENDENT UPON:

1. ALLOWABLE LENGTH OF ROW

DRAINAGE FOR THE SOIL TYPE

ENCOUNTERED.

2. DISTANCE AND AMOUNT OF EARTH

TO BE MOVED TO PROVIDE COMPLETE

ROW DRAINAGE.

3. MAXIMUM LENGTH OF GRADE DRAINING

TO DITCH SHOULD BE 600*.

OUTLET DITCH SHOULD BE

ABOUT I FT DEEPER THAN THE

PARALLEL DITCHES. GRADE BACK

SMALL OVERFALLS ON A NONEROSIVE GRADE. WHERE THIS

ISN'T POSSIBLE OR THE OUTLET

DITCH IS TOO DEEP, USE A CHUTE

DROP SPILLWAY OR A PIPE.

TYPICAL CROSS SECTION OF GROUND SURFACE THAT HAS SOME GENERAL SLOPE

IN ONE DIRECTION AND IS COVERED WITH MANY SMALL DEPRESSIONS AND POCKETS

SMOOTH OR GRADE AREA BETWEEN DITCHES

FILLING DEPRESSIONS AND REMOVING BARRIERS

UNIFORM SLOPE NOT NECESSARY. IMPORTANT

THAT ALL ROWS DRAIN FROM DITCH TO DITCH

USE EXCAVATED MATERIAL FROM DITCHES TO FILL LARGER

DEPRESSIONS OR WASTE ON DOWN HILL SIDE OF DITCH

PREVIOUS SURFACE OF LAND SMOOTHED SURFACE OF LAND

TYPICAL CROSS SECTION OF GROUND SURFACE THAT HAS LITTLE OR NO GENERAL

SLOPE AND IS COVERED WITH MANY SMALL DEPRESSIONS AND POCKETS

ESTABLISH A MINIMUM GRADE OF 0.5% BETWEEN DITCHES

BY CUTTING ON THE LOWER AND FILLING ON THE UPPER END. y

FILL ALL DEPRESSIONS AND REMOVE ALL BARRIERS X ^^~_

USE EXCAVATED MATERIAL FROM DITCHES AS

FILL FOR ESTABLISHING GRADE

PARALLEL DITCHES DESIGNED TO CARRY DRAINAGE RUNOFF

MIN. CROSS SECTIONAL OF 5 SO. FT. AND MIN. DEPTH OF 9 INCHES

SIDE SLOPES

8i| OR FLATTER

FIGURE 11.16 PARALLEL DITCH SYSTEM OF SURFACE DRAINAGE
11-46

b. Determining Runoff Into Field Ditches

(1) This is the first step in design. Generally the same

criteria and process is applicable for computing runoff for

surface ditches as outlined under Part 11.54a, "Determining

Drainage Eunoff." Use applicable curves, Figure 11.4, page

11-16 to determine the amount of runoff to be removed by

the open field ditches. Judgment must be exercised in the

selection of the proper carve. On soils having poor internal drainage use the next higher curve indicated for the

locality.

(2) In determining rimoff generally, start at the lower

extremity of the improvement and work upstream and determine

the c.f.s. (Q) for each reach (length) of ditch. In the

sample Figure 11.10, page 11-33 on collection ditch "A" the

reaches are broken down as follows: 1st reach Sta. O-fOO to

Sta. 14Ö0, 2nd reach Sta. l-MDO to Sta. 7-»00, 3rd reach Sta.

7+00 to Sta. 17+00, 4th reaqji Sta. 17+00 to Sta. 22400.

Reaches in this case were located between points where side

drainage entered. In cases where no concentrated side drainage enters, the reaches should be broken down so that there

are about 20 to 30 acres in each reach. It must be remembered that the c.f.s. (Q) required for each reach is considered constant.

c. Determining Ditch Slope

(1) Determine slope of ditch from plotted profiles of

natural ground slope along ditch location.

(2) Where there is no natural ground slope., or a slope

opposite to ditch flow, a graded ditch must be used with a

minim\im slope of 0.05^ or the minimum specified in the local

Technical Guide.

(3) In determining ditch grades the velocities should be

checked and the maxim-urn grade designed so that the following

allowable velocities are not exceeded.

Bare channels or channels planted to field crops

Sand or silt - 1.5 feet per second

Loams - 2.0 feet per second

Clay - 2.5 feet per second

Vegetated channels

Poor vegetation - 3 feet per second

Fair vegetation - 4 feet per second

Good vegetation - 5 feet per second
11-47

Design Criteria for Single Ditches

(1) The term "single ditch" is used to differentiate from

double ditch ("W" ditch) discussed in the next paragraph.

Single ditches are used where the placement of spoil does

not obstruct surface flow into the ditch.

(2) Depth and Capacity

The ditch capacity should be sufficient to remove the cal-,

culated riinoff. The minimum depth of ditch should be 9

inches and minimum cross sectional area 5 square feet.

(3) Ditch Cross Section

Use 4:1 or flatter side slopes where the ditch may be

crossed by farm machinery but fanning operations are parallel

to the ditch, and 8:1 side slopes or flatter where farming

operations are across the ditch. Where ditches are so

located as not to be crossed with farm equipment, side slopes

of 2:1 may be used.

(4) Spoil Placement

The spoil removed in ditch excavation should be leveled and

so placed that there is no interference with flow of surface

water into the ditch.

Design Criteria for "W" Ditches (double or twin ditches)

(1) This ditch has application where land drains toward the

ditch from both directions, where land is very flat and row

drainage enters from both sides, or where excavated material

will not be used for filling depression. The "W" ditch

actually consists of two parallel ditches, with the spoil

from excavation placed between. In this way surface water

can enter the ditch from each side unobstructed. Figure

11.17, page 11-48. It will be adapted to construction with

the farm plow.

(2) The two ditches comprising the "W" should be parallel

with a minimum of 30 feet between their centerlines.

(3) Depth and Cross Section

Adequate capacity to carry the calculated runoff with a

minimxjm cross section area of 5 square feet and 9 inches

minim-urn depth. Side slope not steeper than 8:1.

(4) Spoil Disposal

The spoil shall be spread in the center area between the two

ditches and slightly crowned. Make the crowned section not

less than 4 feet in width measured from the top inside slope

of one ditch to the top inside slope of the other ditch.
I

00

3) ocmoo

O) (/)

COmoHoO

TI OoocŒOX

NOTE: Where channels ore not maintained

in sod and soil conditions will permit

the side slopes of the channels may

be planted to the field crop. The bottom

of the channel should be left open so

as not to obstruct the flow of water.
11-^9

Determining Bitch Size

Using runoff information and cross sections as outlined above

detennine the ditch size both for single and "W" ditches from

tables Figiire 11.6, pages 11-21 throxigh ll-23a inclusive. In

some cases it may be necessary to interpole between depths

shown in tables.

11.67 Layout and Construction of Surface Drainage Ditches

a. Layout

Layout for construction generally consists of setting centerline

stakes and slope stakes on 100 foot intervals. Slope stakes

usually serve only as a marker of construction limits of the

ditch top width and they are lost or knocked down during early

phases of construction. Under such construction circumstances

it is better to mark cuts on centerline stakes and leave the

stakes on a narrow strip of undisturbed earth until the remainder

of the ditch is down to grade and approximately to final shape.

This method gives the equipment operator an opportunity to check

for depth from time to time by using a rule or hand level. It

is applicable when blade graders, motor patrols, plows, or

whirlwind terracers are used to construct the ditch. When„carryall scrapers, rotary scrapers, small draglines, etc. are used,

it is better to mark cuts on slope stakes and use them to check

from during construction.

Another method commonly used to check construction consists of

setting off-set stakes outside the working limits at a known elevation. Cuts to ditch bottom grade are determined and marked

with reference to these off-set stakes.

b. Methods of Construction

(1) Construction may be done with a moldboard plow, blade

grader, motor patrol grader, whirlwind terracer, carry-all

scraper, rotary scraper, slip scraper, bulldozer, or a small

dragline. "While all of these have been used successfully,

the depth and size ditch will generally determine the most

economical type of equipment to use. If there is no problem

of placing the spoil, the use of a moldboard plow or whirlwind terracer should not be overlooked for the construction

of ditches up to I8 inches in depth. This equipment is

especially well adapted to the construction of "W" ditches.

A whirlwind terracer has an advantage in construction of

shallow ditches for it will spread the spoil over a larger

area than some of the other types of equipment. It is generally more economical to construct ditches of I8 inches to

30 Inches in depth with a blade grader, motor patrol, carryall, rotary scraper, small dragline, or bulldozer. Eefer to

Figures 11.I8, 11.I9, and 11.20 on pages II-50, 11-51, and

11-52. Economical construction with blade grader and motor

patrol is limited to a maximum of about 30-inch depth.
11-50

NOTE: All dimensions are given from the C

The top width as indicated on the drawing is in reality one half of the final top

width of the ditch.

This drawing is based on the use of a two-bottom 14 inch plow» plowing 6 inches deep. If other than

a 14 inch plow is used the rounds can be varied. The main factor in this case is to have the storting width ' 13 feet, the distance A equal to 4'4 feet, and B equal to one and one-half feet.

Remove crop residue and disk heavy sod well before plowing. Remove jointers. Coulters may be left

on. Use sharp shares. Maintain enough speed to turn the furrow slice completely over.

First, the high points should be found. They may be plowed off by laying out short lands and plowing them out. in this plowed out area the top width which is clear of furrows must equal the top

width. After the high points are worked down near to the desired grade, the plowing may be started OS shown above and go from end to end of the ditch.

The first round should start as indicated in the drawing If other cross sections are desired they

may be obtained by variation of the plowing as is indicated in Figure 11.20

FIGURE 11.18 PLOW METHOD OF CONSTRUCTING DRAINAGE DITCH I* DEEP WITH 6 TO I SIDE SLOPES
11-51

NOTE: All dimensions ore given from the t.

The top width os indicoted on the drawing

is in reality one-half the final top width

of the ditch.

igIih^JPiow»!l9-^'6<Iripir:cg^^^^

This drawing is based on the use of a two bottom 14-inch plow, plowing 6 inches deep. If other than a 14 inch plow

is used the rounds con be varied. The main factor in this case is to hove the distance A equal to l\ feet, B equal

to ^\ feet and C equal to I'4 feet with a starting width of 19 feet.

Remove crop residues and disk heavy sod well before plowing. Remove jointers. Coulters may be left on. Use sharp

shares. Maintain enough speed to turn the furrow slice completely over.

First the high points should be found. They may be plowed off by laying out short lands and plowing them out. In this

plowed out area the top width which is clear of furrows must equal the top width. After the high points are worked down near to the desired grade, the plowing may be started as shown above and go from end to end of the ditch

The first round should start as indicated in the drawing. If other cross-sections are desired they may be obtained by

variation of the plowing as is indicated in Figure 11.20

FIGURE 11.19 PLOW METHOD OF CONSTRUCTING DRAINAGE DITCH 11/2' DEEP WITH 6 TO I SIDE
11-52

Ditch /' Deep NOTE All dimensions ore given from the 4..

The top width as indicated is in reality

one half the final top width of the ditch.

SIDE SLOPES STARTING WIDTH A-WIDTH B- WIDTH REQUIRED

TOP WIDTH

4 TO 1 8' 3' 1' 4'

10 TO 1 20' 7V 2V 10'

Ditch I ^ Deep

SIDE SLOPES STARTING

WIDTH A-WIDTH B-WIDTH C-WIDTH REQUIRED

TOP WIDTH

4 TO 1 12' 5' 3' r 6'

10 TO 1 30' 12'4' 7'V 2"S>' 15'

Formula for use of different side slopes:

Storting width» 2 times (required top width)

A, B or 0 « (Distance from proposed ditch bottom to the bottom of furrow being removed

+ V) times ( rotio of side slopes)

If o flat ditch bottom is desired, add one-half of desired bottom width to "starting

width " "A", "B" and "C.

FIGURE 11.20 DIMENSION CHART FOR CONSTRUCTING DRAINAGE DITCHES
11-53

(2) Spoil spreading is very important in surface ditch construction. Spoil should be spread over large enough area in

the field adjacent to the ditch so that it will not block

water movement from the field to the collection ditch, or in

depressional areas. Spoil spreading is done with drags,

motor patrols, blade graders, bulldozers, carry-alls, and

rotary scrapers. However, a more recently developed piece

of equipment known as the "land leveler" appears to have

merit for spoil leveling.

(3) Since ditch gradients are usually very flat in s-urface

drainage systems they require extreme care in construction,

and a thorough check should be made before equipment leaves

the Job so that necessary corrections can be made.

11.68 Land Smoothing (Grading) for Surface Drainage

a. General

While land smoothing is not in itself a type of surface drainage,

its use is so closely associated that it is included in this

part of the handbook. Land smoothing is the grading or planing

by mechanical means of the land surface to eliminate or reduce

elevated areas and fill minor depressions. It should be clearly

understood that land smoothing is not land leveling. The purpose is not to make the field level but to make it "smooth" so

that surface water will flow off, due to the natural fall of the

land. Many ills of drainage could be corrected by this simple

expedient. It has application especially in conjunction with

the installation of surface drainage systems.

b. Land Conditions Where Smoothing is Applicable

(1) Land smoothing has application under a rather wide

variety of conditions, but its primary use is in depressional

topography on the heavier soils. On these soils water flows

to the depressions and the soil is too impervious to allow

infiltration, consequently these parts of the field remain

wet for several days following a rain. By smoothing out

these depressions water is distributed or runs off and the

field dries more uniformly, allowing it to be worked sooner.

Water will collect in very slight depressions scarcely

visible by eye; smoothing out these irregularities in the

ground surface eliminates the opportunity for water to

acc-umulate. Most fields have enough natural fall to permit

the excess water to flow off, provided it does not concentrate in a low spot.

(2) Adequate soil investigations should be made prior to

smoothing to determine the depth of topsoil. The field to

be smoothed should have sufficient depth of soil to prevent

exposure to harmful amounts of subsoil.
11-5^

(3) Field ditches may "be needed to collect and remove surface rxmoff j consequently outlets for these surface ditches

should be available.

c. Specifications for Land Smoothing

(1) Depth of Grading

Depth of grading should be controlled so as to prevent

exposing harmful subsoil. Adequate investigations shall be

made to determine the depth of topsoil^ and the depth of

grading that will be pennissible.

(2) Finished Surface

Specifications for the finished surface will vary for each

job since every field is a different problem. It should be

kept in mind that the objective is to grade the field so

that runoff will have imobstructed flow to collection or

field ditches. It is not necessary to grade the field to

the extent that there is a uniform slope over the entire

field length. The finished surface should be smooth and

free of all minor depressions, but the slope may vary whenever it will decrease the amoimt of earth to be moved.

(3) Field Drains

Field drains should be provided to drain depressions too

deep to fill. In addition collection ditches should be

installed to collect surface water from the field and reduce

length of row drainage. Suitable outlet ditches should be

available to remove the runoff.

d. Land Smoothing Operations

Land smoothing generally can be accomplished more satisfactorily

in two operations: First, rough grading the area by eye; second,

smoothing or finishing sometimes known as "floating." These

operations can be done in the same year, but if there are depressions of appreciable depth better results probably will be

obtained if the work is done over a 2-year period in order to

give the fills a chance to settle.

(1) Rough Grading the Area

Rough grading the area by eye is the first step. The method

of doing this and the type of equipment used will depend

upon the amount of cutting and filling to be done. For small

amounts of earth moving, if the cuts are only 6 inches and

the hauls 300 feet or less, then the work may be accomplished

with a land leveler or even farm tractors and rotary Fresno.

But where large amounts of earth are to be moved either a

bulldozer or contract equipment are more economical. The

maximum distance for economical moving of earth with the
11-55

bulldozer is generally 300 to 400 feet, with a skilled operator, preferably 300 feet; with a partially skilled operator,

200 feet. Moving appreciable amounts of earth for greater

distances generally can be accomplished more economically

with heavy contract equipment.

If there is a deep depressional area or a wide shallow

depression it may be more economical to drain these areas by

field ditches rather than to fill them.

In making cuts avoid completely removing topsoil from any

one area. Instead, take thin layers of topsoil from a much

larger area. Since the slope is usually gradual the soil can

be moved into the depression by cutting high ground uphill,

downhill, or to the side, thus permitting round-trip operations . In rough grading by eye keep in mind that the purpose is to make the field drain and not to uniformly grade

the entire area. Figure 11.21, page 11-56. After the area

has been rough graded the land leveler or land plane shoiild

be run over the area from two to four times depending on the

roughness of the land. It should be operated across the

area and then diagonally both ways. Prior to the last pass

with the land leveler clean the existing field ditches,

distributing the spoil as far back from the ditch as is

feasible. The final pass with the land leveler will then

smooth out the spoil. When rough grading is completed the

area should be reasonably free of depressions where water

will stand.

(2) Final Smoothing Operations

Following rough grading it is desirable to allow at least a

few months for settlement of the soil before final smoothing

operations. If possible, it would be desirable to wait a

full year. The field to be smoothed should be dry, either

plowed or disked, and free of vegetation and trash.

Rainfall following rough grading will give indications of

the need for additional cutting and filling. However, some

topographic survey information is generally required, to

locate small depressions missed during rough grading operations, and to select and plan the type of surface drainage

system best suited for the field. Then construct any new

surface ditches required for the selected surface drainage

system. The spoil from the new ditches can be used to fill

adjacent depressions that were not completely filled by the

roiigh grading. Fill remaining depressions as indicated by

the topographic STiirvey, The last phase in the land preparation is to operate the land leveler or plane diagonally

both ways of the field and then across the field in the

direction of planting operations.

A method of runiilng levels that has proved satisfactory is

to set grade stakes where the need for additional work is
11-56

ADVANTAGES OF LAND SMOOTHING

1 Land smoothing eliminates the small

low areas and pockets that collect and

hold water. This mokes possible earlier

planting,o longer growing season and uniform stands and crop yields.

2 Prepares an ¡deal seed bed, firms the

soil and leaves o smooth uniform surface which will hold sub-moisture near the

surface in dry weather and afford a well

drained seed bed in wet weather.

3 Permits uniform planting depths onda

covering of seed with well-pulverized

soil,all of which insures faster and more

uniform germination of seeds, better stands,

hardy and rapid-growing plants.

^ Mokes cultivation more uniform and

weed-removal more complete by providing a smooth surface on which to work.

5 Mokes mechanical harvesting faster and

more efficient,especially on low-growing or vine crops by allowing operation of

pickup devices closer to the ground.

Q Saves wear and tear on planting,cultivating and horvesting machinery. Farm

machinery will operate better and lost

longer with fewer repairs on smoothed fields.

TOPOGRAPHIC MAP OF FIELD

101.0 •

100.0

99.0

Move high poini^ ^m^ humps

/>7/ö pocMe/a onefefimpressfons

Origina/ Grounc/-

1C Grade of field af^er jimooihJng

Field Dif-ch *&' ,PocÁrefs ivfVere wafer_

co/Jecfs and sfortde

101.0

lOO.O

59.0

PROFILE OF GROUND ALONG A-AABOVE

FIGURE 11.21 EXAMPLE OF FIELD WHERE LAND SMOOTHING IS APPLICABLE
11-57

indicated. Grade the area by setting stakes on approximately

100 foot intervals, marking the amount of cuts on the stakes

and a line on the fill stakes to indicate the height of fill.

The area can "be worked in lanes leaving the cut stakes on

islands of earth, and not dist-urhing fill stakes until the

proper fill has been made. This work is done with earthmoving equipment as used for rough grading. The land

leveler can then be used to smooth out surface irregularities and remove the islands at the cut stakes. Generally

rough grading machinery is used to within 0,10 foot of the

finished grade before, using the land leveler.

Final grading need not be carried to the point of obtaining

uniform slopes over long distances since the primary purpose

is merely to grade the field so that it will drain. However,

some fields are nearly level and water will not run off.

These fields should be provided with some grade. The minimum grade should be 0.05 i*oot fall per 100 feet (0.05^).

This grade can be established only where there is sufficient

topsoil on the lower end of the field to provide the necessary borrow for the higher side.

e. Maintaining Fields in Smooth Condition

In the farm tillage operations ridges, back furrows, or

irregularities develop where water will stand, and it is

therefore vitally important on tight soils to maintain the

land in a smooth condition. The best way to accomplish this

is by using the land leveler as the last step in seedbed

preparation prior to seeding or planting operations.

11.69 Maintenance of Surface Drainage Systems

No other practice used in soil and water conservation work is

more dependent on meticulous maintenance for proper functioning

than surface drainage systems. This is particularly true of

bedding systems. The following points in maintenance especially

should be observed.

a. Maintenance of Field Ditches

Outlets and collection ditches should be cleaned and reopened

periodically as required to permit them to function properly.

Small deposits of silt will oftentimes greatly reduce capacities and cause partial or complete failure of the system. After

each heavy rain the ditches should be inspected and silt deposits

or other obstructions removed. Cattails, water tolerant grasses,

willows, and cottonwood are a menace to surface ditches and

should be cut or sprayed once or twice each year as required.

b. Maintenance of Bedding Systems

(1) When the field is in row crops the dead furrows generally need to be opened after each cultivation. This is
11-58

especially important on very flat land and diiring the time

the plants are small. A V-shaped drag is useful for this

purpose.

(2) On fields that drain very slowly to slow^ beds once

established should be maintained permanently in the same

location. A properly shaped bed should have a continuous

slope totalling 3" to 5" from center of bed to shoulder of

dead furrow^ and dead furrow should have an additional depth

of 3" to W' below the shoulder line^ making a total difference of from 6" to 9" from center of bed to bottom of dead

furrow.

(3) Once a permanent type of bed is established a particular

method of plowing is required so as to prevent the beds getting too high in the center and the dead furrows developing

into a progressively wider sterile area. One method is to

use a two-way plow. Plowing is started at one side of a

field and continued across the field^ throwing all the furrows in one direction. This will merely move the center of

the beds and dead furrows over one furrow width. The next

plowing is started on the opposite side of the field; thus^

the beds are always maintained about the same height. However^ it may be necessary after each plowing to open up the

dead furrows with a small V-drag or the plow itself. Unfortunately there are very few two-way plows on the farms in

this region.

(k) Another method is to use the common one-way plow and

plow two beds as a land. By alternating the starting points

on each successive plowing the bed heights and dead furrow

widths are maintained about as originally established. See

Figure 11.22, page 11-59.

11.70 TILE DRAINAGE

11.71 General

a. Tile drainage is accomplished by means of a series of tile

laid in a continuous line at a specified depth and grade so that

free water entering the tile Joints will flow out by gravity.

It differs in principle from surface drainage in that water percolates into the soil and is taken out by drains below the ground

surface.. The pui^ose is to lower the ground water level below

the root zone of the plants.

b. A tile drainage system consists of a drainage outlet, tile

main, sub-mains, and laterals. The function of the laterals is

to remove the free water from the soil; the function of the submains and mains is to carry the tile water to the drainage outlet .
11-59

CONSTRUCTION OF BEDS

EXTREME CARE MUST BE USED DURING THE FIRST PLOWING TO DEVELOP BEDS OF UNIFORM WIDTH

THROUGHOUT THEIR ENTIRE LENGTHS.

START PLOWING BY BACKFURROWING AT CENTER OF BED, THROWING FIRST TWO FURROWS TOGETHER.

CONTINUE THROWING FURROWS TOWARD THE BACK FURROW UNTIL WIDTH OF BED HAS BEEN PLOWED.

IF THE REQUIRED CROWN HEIGHT AND SIDE SLOPE OF BED HAS NOT BEEN SECURED, REPLOW THE BED

CROSS SECTION OF BED SHOWING CONSTRUCTION METHOD

IN A LIKE MANNER.

MAINTAINING BEDS

FIRST PLOWING AFTER BEDS ARE ESTABLISHED

START PLOWING OPERATIONS TO THE OUTSIDE OF DEADFURROW "B" THROWING FIRST BACKFURROW SLICE ON EACH SIDE

ONLY PARTIALLY INTO THE DEADFURROW SO THAT AT LEAST A 12-INCH WIDTH OF THE OLD DEADFURROW REMAINS.

CONTINUE PLOWING BY THROWING FURROWS TOWARD DEADFURROW "B" UNTIL DEADFURROWS Va"c"ARE REACHED. MOVE

TO NEXT TWO ADJOINING BEDS AND REPEAT OPERATION.

PLOW TWO BEDS AS ONE UNIT OR LAND

ROUND 2

' LAST

MAINTAINING BEDS

SECOND PLOWING AFTER BEDS ARE ESTABLISHED

START PLOWING AT DEADFURROWS V 8 "c", THROWING FIRST BACKFURROW SLICE ONLY PARTIALLY INTO THE DEADFURROW

SO THAT AT LEAST A 12-INCH WIDTH OF THE OLD DEADFURROW REMAINS WHEN THE ADJOINING BEDS ARE PLOWED. CONTINUE

PLOWING BY THROWING FURROWS TOWARD DEADFURROWS "A" 8 "c" UNTIL DEADFURROW "B" IS REACHED. THE THIRD TIME THE

FIELD IS PLOWED, FOLLOW PROCEDURE FOR FIRST PLOWING.

PLOW TWO BEDS AS ONE UNIT OR LAND

ROUND 2 LAST 4^ ROUND ROUND t

BED WIDTH

AFTER SEED BED HAS BEEN'

PREPARED IT M^Y TBE

NECESSARY TO CLEAN OUT

DEADFURROWS "A"a"c" IN

ORDER TO INSURE ADEQUATE

DRAINAGE.

BED WIDTH

FIGURE 11.22 CONSTRUCTING AND MAINTAINING BEDDING SYSTEMS FOR SURFACE DRAINAGE

259293 O - 53 - 16
11-60

11.72 Conditions Under Which Tile Drainage Is Applicable

a. Tile drainage is applicable to more or less saturated soil

conditions where it is physically and economically feasible to

remove free water throiigh tile under drains to the normal depth

of the plant root zone . The inherent fertility of the soils

must be such that after drainage the land will produce sufficient

additional crops to justify the expense of tiling.

b. Soils Suitable For Tile Drainage

(1) Tile drainage is affected primarily by the rate of movement of water percolation in the soil. This in turn depends

upon the size and niomber of connecting pore spaces. In general the finer textured soils have a slower rate of percolation. In heavy soils the pore spaces are small and clogged

with collodial material obstructing gravitational flow into

the tile line. Some of these soils are so tight that the

tile remove the free water from only a limited area. If

such soils are to be drained the tile would have to be placed

so close together that the crop returns would not Justify the

expense. The use of tile in clay soil^ therefore^ is limited

to soil physical conditions where the spacing of the til^

lines are at such a distance that the cost of installation

is not greater than the benefits derived.

(2) In some sandy soils and in peat and muck the pore space

is large and the movement of water is rapid. Wetness occurs

because of a high water table particularly in the spring.

This must be lowered by drainage if maximiim crop yields are

to be produced. Soils of this type can be successfully tile

drained but many of them present certain hazards.

(a) In some fine sandy soils there is insufficient

colloidal material to hold the particles together and

there is danger of excessive movement of the sand particles into the tile line. Some of these soils cannot be

tiled and on others^ special precautions in construction

are necessary.

(b) In peat and muck soils there is also some tendency

for the fine soil particles to enter the tile line, and

in addition there is a danger of shifting of the tile

alignment due to the unstable nature of the soil. Furthermore, there is a tendency for newly drained muck and

peat soils to settle considerably. For this reason,

generally, it is not desirable to lay tile in these

soils until the initial settlement has taken place.

(c) Both sandy soils and peat and mucks present some

hazards of over-drainage. Being very porous they have a

low capillary attraction and if the water table is lowered too much by the tile line the capillary "pull" is

not sufficient to bring the water into the plant root

zone.
11-61

(d) There are still other soil conditions where tiling

is hazardous or impossible. In some soils boulders or

stones are encountered so frequently that tiling costs

are prohibitive. In other soils the topsoil is satisfactory but it is underlaid with sand at the depth where

tile would be installed^ thus making installation more

difficult or impossible. In still other soils there is

a tendency for the tile joints to seal over due to a

chemical action that takes place.

c. Economic Factors to Consider

(1) Some soils can be tile drained satisfactory but the cost

of installation is so great that the accrued benefits do not

justify the expense. This condition is true on extremely

tight soils where spacing must be very close. A rule-ofthumb that has quite general application is that when tile

spacings are closer than two rods (33 feet) the cost usually

is greater than the benefits. An exception to this is where

high value crops are involved. An example of this is the

tile drainage of Nappanee soils in Michigan that are planted

to orchards. The benefit here not only is in the removal of

excess water for tree growth but also in drying up the land

so that spray rigs can be hauled through the orchard without

bogging down.

(2) Some soils could be drained by tile satisfactorily but

the inherent productivity is so low that the yields do not

justify the expense involved.

(3) Another economic factor that prohibits many tile installations is the lack of a suitable outlet. To provide for a

tile outlet^ in some cases^ would be prohibitive in cost.

{k) Most tile drainage is expensive and in many cases farmers do not have the money to spend on an installation. The

amount of indebtedness that should be incurred is difficult

to decide. Over a period of years the installation may pay

for itself; but if a series of reverses occurs in farming

the debt may be too great to finance during periods of low

income. A good rule to follow is to not encourage borrowing

for tile drainage installation unless the returns by increased crop yields will pay for the installation in a fiveto seven-year period.

d. In conclusion it may be said that before undertaking tile

drainage of any piece of land a careful analysis should be made

of the physical and economic conditions involved in the installation.

11.73 Field Surveys For Tile Installations

a. General

(l) Prior to making a field siirvey for tile installation

the technician should make a preliminary investigation and
11-62

inspection of the field to be drained. The various factors

affecting drainage outlined in Part 11.72 should be carefullyinvestigated and considered. These should be discussed fully

with the landowner. Before making the survey the following

decisions should have been reached:

(a) That the soils will respond to tile drainage and

that there are no physical soil conditions prohibiting

the installation of tile.

(b) That a suitable arrangement of tile is feasible and

an outlet is available. If this is not evident by eye^

sufficient preliminary levels should be taken to reach a

decision.

(c) The areas in need of drainage should be delineated

preferably on an aerial photo. The technician should

have a general idea of the type of tile system required.

Such a determination in advance is desirable so that the

nature of survey can be planned before starting the s\irvey.

Two kinds of field information especially are required for

the design of tile drainage installations: topographic data

of the field to be drained, and soil borings or knowledge of

the soil profile.

b. Topographic Information Required

(1) The amount of topographic information depends on the lay

of the land. Where the slope of the land is obvious by eye

very little and sometimes no topographic information is

needed to plan the location of tile lines. But on flat land

where the location of tile lines is not obvious, a topographic survey is necessary. The general tendency is to obtain

too little topographic data. Lack of topographic information

results in a piecemeal system of tile drainage that frequently is more expensive than if sufficient information had

been obtained to plan a complete job on paper in advance of

installation.

(2) The method of making topographic surveys and preparation

of topographic maps is outlined in Part 1.40, and further

explanation is given in Parts 11.52 and 11.53 under Surface

Drainage. These procedures are generally applicable to

obtaining topographic information for tile drainage installations .

c, Soil Borings

(1) Unless sufficient soil borings are taken when the preliminary inspection was made of the area these should be

taken as a part of the survey. The number of borings to

make on any particular area under investigation will depend on
11-63

several factors but principally on apparent differences in

soil appearances, or as indicated by soil surveys. A sufficient number of borings should be made so that the technicians will definitely know if there are undesirable soil

conditions or if there is a wide variation in the texture of

the soil to be drained. This information is definitely

needed to determine the spacing and depth of the laterals

and construction hazards.

11.74 Types of Tile Drainage Systems

In order to plan a tile drainage system, knowledge is needed of

the various types of tile drainage systems. The six types of

tile drainage systems commonly used are shown in Figure 11.23,

page II-63 and Figure 11.2^, page 11-64. The choice of systems

FIGURE 11.23 DRAINAGE AT SEEPAGE AREAS

to use is determined by the topography of the land, source of

water to be removed, and other field conditions. The different types of tile drainage systems are described as follows:

a. Eandom System

This system is used where there are scattered wet areas in a

field somewhat isolated from each other. Tile lines are laid

more or less at random to drain these wet areas. In most cases

the tile main follows the largest natural depression in the
11-64

) I) I) o (I ') ' ) <l

) <) I) () ') > I) ()

) ) I ) > i o )

I) i> <) I) <l l> (I o

—a—I 1—e—I 1—.«—I 1—a

PARALLEL GRIDIRON HERRING-BONE

GROUPING 1

FIGURE 11.24 TYPES OF TILE DRAINAGE SYSTEMS
11-65

field and the sub-mains and laterals extend to the individual

wet areas. If the individual wet areas are large the arrangement of the suh-main and laterals for each wet area may utilize

one or more of the other systems shown in Figure 11.2^1-.

b. Gridiron and Parallel Systems

The principle employed in these two systems is that one main or

sub-main serves as many laterals as possible. Thus the length

and number of outlets is kept to a minimum. Since the laterals

enter the sub-main from one side only there is less ^'double

drainage" than where laterals enter the sub-main from both sides.

This system is applicable on land that is imiformly wet where

there is a gentle slope toward the sub-main.

c. Herringbone System

This system is applicable where the sub-main lies in a narrow

depression and the laterals must enter from both sides. It is

a less economical system, since there is considerable double

drainage where the laterals and mains join. However, if the

depression over the sub-main is unusually wet this system will

provide better drainage at this point and thus be an advantage.

d. Intercepting System

This system involves the interception of seepage water from

adjoining high lands. A line of tile properly located will

intercept the seepage water and relieve the wet conditions. The

proper location of the tile for interception of the seepage

water is highly important. The seepage plane should first be

located by soil borings^ or with a post-hole auger, and the tile

installed on or just slightly above the impervious layer. Refer

to Figure 11.23, page 11-63.

e . Double-Main System

This is a modification of the gridiron system and it is applicable where the sub-main is located in a broad, flat depression

which is frequently a natural watercourse. In some cases this

depressional area may be wet because of small amounts of seepage

water from adjacent slopes. Placing a sub-main on each side of

the depression serves the double purpose of intercepting the

seepage water and as a sub-main for the laterals. If the depression is unusually wide and only one sub-main is used in the center it may be necessary to break the grade line of the laterals

before they reach the sub-main. Placing a sub-main on each side

of the depression permits a more uniform lateral grade line without an abrupt break in grade.

f. Grouping System

This system employs the use of a combination of the individual

systems. It is applicable where there are variable conditions
11-66

of wetness on the field to be drained and the pattern of drainage

must be varied to fit the individual conditions.

11.75 Planning the Tile System

a. General

The purpose of the field survey, soil borings, and other field

information as described in Part 11.73 is to provide adequate

information from which the most economic system of tile drainage

can be planned. This information should be studied and utilized

fully in planning the system. The importance of thorough planning in advance of layout cannot be over-emphasized.

b. The Tile Outlet

(1) The starting point in planning a tile drainage system

is the location of the outlet. Tile drains may outlet by

gravity into natural or artificial channels or tile outlet

mains. Any of these are suitable provided they are deep

enough and of sufficient capacity to take away all the

drainage water from the tile line. Before proceeding with

the design of the system the technician should be satisfied

with the adequacy of the outlet.

(2) Capacity and Depth of Open Channel Outlets

The outlet channel shall be large enough to remove the drainage rimoff from the watershed in a period of time sufficient

to prevent crop damage. It shall be deep enough so that when

tile lines are laid at the specified depth there is at least

one foot of clearance between the flow line of the tile outlet and the low water stage in the channel. This clearance

may be reduced where the outlet channel is on such a grade

that silting will not occur and where the stream recedes to

low water stage a few hours after a storm.

(3) Capacity and Depth of Tile Mains

When existing tile mains are used as the outlet, it shall be

in good condition, free of failures, and working properly.

The main shall have sufficient available capacity, based on

the area served, to handle the proposed tile drainage system,

and the depth should be sufficient to permit the new tile

system to be laid at the depth specified for good tile

drainage (excepting small depressions where minimum cover of

two feet is permissible).

(k) Outlet by P-umping

Where a gravity outlet is not available the possibilities of

an outlet by pumping should be considered. This is a special

problem that should be investigated by an engineer. See

Part 11.42e, page 11-11, for additional information.
11-67

Some General Principles in Planning the Tile Systems

(1)' The success of the tile drainage system depends upon

the efficiency with which the laterals remove the free

water from the soil. Therefore they are a very important

part of the system. The determination of the proper depth

and spacing of the laterals and their relation to the main

should receive careful consideration. Especially the following:

(a) The laterals should be laid out to be as long as

possible, within the limits of topography. A good rule

to follow is to make the laterals long and the mains and

sub-mains short.

(b) The laterals should enter the mains at nearly right

angles whenever possible. Long slanting junctions should

be avoided because this results in more double drainage.

Do not use designs where laterals enter a main or submain from both sides, such as the herringbone system,

unless it is necessary for good drainage, as this also

results in double drainage.

(c) Avoid laying tile lines within 100 feet of waterloving trees, such as willow, elm, cottonwood, or etc.

and maintain a distance of 50 feet from all other tree

species with the exception of orchard trees. Where this

distance cannot be maintained the tile line should be

constructed of bell Joint or tongue and groove tile with

joints sealed with mortar.

d. Determining Tile Size

(1) Drainage Coefficient

The tile should be of sufficient capacity to remove a

required amount of water (inches) from the area to be drained

in 2k hours. This amount of water is referred to as "drainage coefficient." The drainage coefficient to use depends on

soil and crop conditions and the method of disposal of surface water. Truck crops require the removal of water within

a few hours* time following a rain, and therefore a higher

drainage coefficient is required. Where there are surface

inlets the inflow into the tile is greater than where sur-

' face water is excluded. The following table gives recommended drainage coefficient for tile systems without surface inlets and with surface inlets.

(2) Size of Tile to Use

(a) The size of tile needed is based on the size of area

drained, grade of tile, and the specified drainage coefficient. With this basic information tile size can be

determined from Figure 11.25, page 11-69, "Tile Drainage

Chart."
11-68

DRAINAGE COEFFICIENT FOR VARYING CROP AND SOIL CONDITIONS

WITH AND WITHOUT SURFACE INLETS

Soil

Without 2/

Surface Inlets

With 3/

Surface Inlets

Permeability Field Crops

1/

Truck Crops Field Crops

u

Trucl( Crops

Mineral Soils 3/8" 3/4" 3/h" le"

Peats & Mucks 3/i^" 1 to li" 3/4 to le" 4 to k"

1/ For mineral soils with sandy or otherwise permeable subsoils the

drainage coefficient may be reduced - never less than l/4".

2/ Figure only the area to be tiled as the drainage area. It is under-

"" stood that surface water is removed by field ditches or watercourses.

3/ Use entire contributing watershed as the drainage area.

(b) The smallest tile generally recommended is five

inches, even though the chart calls for the use of

smaller tile. Four-inch tile may be used on single laterals not exceeding 1,000 feet, where the grade is .15

percent or less, and this length can be increased to

1,300 feet for grades steeper than .15 percent. In deep

peat and muck soils six-inch tile should be the minimum

size used because of shifting of the tile alignment.

Also for intercepting areas of considerable seepage or

strongly flowing springs the minimum size tile should be

six inches.

(c) Individual tile lengths for mineral soils usually

are one foot. For peat and muck soils tile lengths 18

to 2k inches are recommended in order to avoid tilting

of the tile.

e. Depth and Spacing of Tile Lines

(1) General

The depth and spacing of tile should be such as to lower the

depth of groimd water between tile lines within 2k hours

after a rain to that required to prevent crop injury. Generally, crops are not injured if the water table is lowered

to at least six inches below the ground surface in the first

2k hours following a rain. During the second and third day

following a rain the ground water level should be lowered

approximately to the 1 foot and 1.5 foot level respectively.

(2) Minimum Tile Depths

(a) Laterals should have an average minimum depth of

three feet in mineral soils. Generally it will be found

that even greater depths, 3-1/2 to k feet, will give
TILE DRAINAGE CHART

Acres Droined by Vorious Sizes of Tile

11-69

THe grade in inches per 100 feet

2 3 4 5 6 7 8 9 101112

0.1 0.2 0.3 0.4 0.5

Tile grade in feet per 100 feet

Space between tines is ttie range of tile

capacity for tt)e size shown between Lines.

Reference: Yarnell-Woodward Formula V'l38r ^s ^ U.S.D.A. Bulletin 854

^ V. equals velocity in feet per second

REVISED 11-21-51

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

ROBERT M. SALTER,CHIEF

UPPER MISSISSIPPI REGION

MILWAUKEE, WISCONSIN

R.H.MUSSER, DIRECTOR 3-L-72I5

FIGURE 11.25 TILE DRAINAGE CHART
11-70

better results and there has been a growing tendency to

use deeper placed laterals. For slowly permeable soils

where laterals are spaced approximately 50 feet the depth

may be reduced to 2.5 feet under certain conditions. In

deep organic soils where settlement has occurred the

minimum depth should be ^ feet,

(b) In small depressional areas where it is uneconomical

or impractical to place tile at the depth specified

above, the depth may be reduced to a minim-um of 2 feet

of cover. This minimum depth is necessary in order to

prevent frost damage and to prevent breakage by farm

machinery loadings. For depths shallower than 2 feet

use continuous length of frost-resistant pipe of sufficient strength to resist farm machinery loadings such

as corrugated metal pipe or extra strength bell Joint

or tongue and groove tile.

(c) The mains and sub-mains should be deep enough to

provide the specified depth for laterals.

(3) Tile Loading

The maximum depth at which tile can be laid varies with the

width of trench and it is dependent upon the crushing

strength. The allowable maxim-um tile depth for various

widths of trenches is given in the following table:

MAXIMUM ALLOWABLE TILE DEPTH IN FEET FOR DRAIN TILE WITH VARYING

WIDTHS OF TRENCH \J

Tile Tile

Strength

Width of Trench - Inch es

Size 14 16 18 20 22 2* 26 28 30

5"

Standard

Extra Quality

^Inf. 16.5

Inf.

8.7

Inf.

7.2

12.0

7.2

9.5

7.2

9.5

7.2

9.5

7.2

9.5

7.2

9.5

6"

Standard

Extra Quality

ti

ft

8.8

Inf.

6.7

12.1

6.5

8.6

6.5

8.5

6.5

8.5

6.5

8.5

6.5

8.5

8"

Standard

Extra Quality ti

9.0

Inf.

6.9

12.3

5.7

8.8

5.1

7.3

5.1

G.G

5.1

6.G

5.1

e.e

10"

Standard

Extra Quality

»1

It

9.2

Inf.

7.1

12.4

5.9

9.0

5.2

7.5

k.6

6.5 5.7

4.6

5.6

12"

Standard

Extra Quality

It

It

9.h

Inf.

7.3

12.6

6.1

9.2

5.i^

7.7

1+.8

6.7 5.9

4.2

5.4

15"

Standaird

Extra Quality

11.3

Inf.

8.5

12.9

6.9

9.5

6.2

8.0

5.5

7.0

5.0

6.2 5.7

18"

Standard

Extra Quality

9.9

19.2

7.9

11.5

6.9

9.7

6.3

7.5

5.6

7.2

5.3

6.7

^Inf. z infinity

1/ Reference : Based on Marston's formula.
11-71

(k) Tile Spacing

The spacing between laterals should vary according to soil

types. The following spacings are general recommendations.

These may be varied according to local experience as specified in Technical Guides.

RECOMMENDED TILE SPACING FOR VARIOUS SOILS

Soil Permeability Spac ing

Clay and clay loam Very slow 30 to 70 ft.

Silt loam Slow to moderately

slow 60 to 100 ft,

Sandy loam Moderately to

rapid 100 to 300 ft,

Muck and peat — 80 to 200 ft.

f. Tile Grade Limitations

There are both maximum and minimum grade specifications for drain

tile that are considered good drainage practice.

(1) Minimum Eecommended Grades For All Tile Lines

k inch^ 5 inch^ and 6 inch tile - 0.1 percent

8 inch and 10 inch tile - 0.08 percent

Larger size tile - O.O5 percent

In sandy soils the minimum allowable grade should produce a

velocity of at least 2 feet per second.

(2) Maximum Grades For Tile Lateral

(a) The maximum grade for tile laterals frequently must

vary with topographic conditions and it is not always

possible to adhere to a specified maximum grade. Single

laterals are not likely to give difficulty due to steepness of grade under most soil conditions (excepting fine

sandy soils)^ provided the line is not overloaded; furthermore, failure of a single lateral is not so serious

as it affects only one line. Tile sizes should be carefully determined for adequate capacity. If there is a

change from a steep to a lesser grade the size of tile

may need to be increased to provide adequate capacity.

In fine sandy soils the maximum grades for laterals need

more careful consideration and special construction precautions as outlined below under til^ mains in sandy

soils are applicable.
11-72

(3) Maximum Grade For Tile Mains and Sub-Mains (excepting in

fine sandy soils)

The following maximimi grade specifications apply to all soils

except fine sandy soils which are treated separately below:

(a) Where tile mains and sub-mains are designed for nearcapacity flow and installed without special construction

features, the maximiim grade should be one percent. This

may be increased to two percent provided the tile are

. laid without a gap between the joints and clay is tamped

thoroughly under and around the tile. Where the line is

designed for capacity 50^ greater than the estimated tile

flow and special construction precautions as mentioned

above are used, the grade may be increased to four percent,

(b) Where the slope exceeds two percent and the tile main

is designed for near-capacity, sealed bell-type tile should

be used.

(c) A breather should be installed at or near the beginning of a steep section of the main. A relief well should

be provided at the point where the steep section changes

to a flat section, unless the capacity of the flat section

exceeds the capacity of the steep section by 25^. Figure

11.32, page 11-80.

(k) Maximum Grade For Tile Mains in Sandy Soils

Because of the lack of cohesiveness of the sand particles,

tile laid in sand on any appreciable grade are likely to

cause trouble because the free water entering the Joints

carries the sand particles with it. Also, irregularities in

tile Joints cause disturbed flow in the tile. As velocity

increases on steeper grades turbulence becomes greater with

the result that a hole may develop on the outside of the Joint

which may cause shifting and blocking of the tile line. Consequently, in sandy soil conditions tile mains should not be

laid on grades steeper than one percent unless bell-type or

tongue and groove-type tile are used. Even on grades under

one percent special precautions in construction are desirable

such as the following:

(a) Use only good quality tile, uniform in shape and

size with smooth ends so that the closest possible Joints

can be made.

(b) The wrapping of the Joints with tar roofing paper or

similar material is frequently resorted to under extreme

conditions. Other methods are to use slough grass, straw,

or similar material as a filter around the tile to keep

out the sand,

(c) It is important to blind the tile with topsoil to a
11-73

ininimiim depth of 12 inches immediately after placing to

preserve grade and alignment. The trench should not be

backfilled further until the free water has been removed

and the tile have become stabilized.

(d) The more complicated problems involving tile placement in quicksand are not discussed here because it is

beyond the scope of this handbook. For these, as well as

other unusual sand conditions, consult an engineer for

recommendations.

g. Miscellaneous Specifications For Tile Systems

The following additional specifications are important and should

be considered a part of the construction specifications:

(1) Alignment

Curves in mains or lateral lines should have a minimum radius

of 50 feet. Where the gap between tile on the outer side of

a curved line exceeds l/h inch in clay soils and 1/8 inch in

sandy soils it should be covered with broken pieces of tile,

Figure 11.26. However, at the junction of tile laterals

imm^^m^^^^^^^m^Tmmm

L - r:

Width of ¡oinfs:

g minimum to a maximum of ¿

Tile bab oy^r wider joints and curves

FIGURE 11.26 CORRECT METHODS OF LAYING TILE
11-7^

with mains this curvature is not necessary and the laterals

may enter at right angles. Use a manufactured "T" or other

approved method of making the connections. See paragraph

11.75h(2), page 11-T?. To compensate for the ¡possible loss

of head for a right-angle junction, an additional drop of

0.1 or 0.2 foot can be planned for the last 25 to 50 feet of

the lateral where it enters the main.

(2) Connections

Manufactured connections or branches for Joining two tile

lines are recommended, Figure 11.27.

FIGURE 11.27 TILE JUNCTION USING Y AND T CONNECTIONS

If connections are not available, the Junction should be

chipped and fitted and the connection sealed with mortar.

Laterals should be connected into the main tile at the midpoint.

(3) Joints

The gap between tile should be about 1/8 inch unless the

soil is sandy; then the width of the gap should be reduced

to a tight fit. When the gap exceeds 1/8 inch in sandy

soils and 1/4 inch in clay soils the opening should be

covered with pieces of broken tile carefully placed or

wrapped with heavy tar roofing paper. In sandy soils roofing paper is preferable.

(k) Blinding

As soon as the tile are placed and inspected they should be

"blinded" by covering them to a depth of 6 to 12 inches with
11-75

loose mellow topsoil shaved from the sides of the trench.

All tile should be blinded by the end of the day's work. In

tight soils a layer of several inches of gravel spread over

the tile before blinding prevents the Joints from sealing

and facilitates drainage. Hay, straw^ corncobs, and similar

material can be used as a substitute covering over the joints

but its period of usefulness is limited.

(5) Crossing Waterways and Roads

Special precautions should be taken where tile are placed

under waterways or roads. If the cover over the tile is 2.5

feet or less, one of the following practices should be followed:

(a) Encase the drain tile in concrete.

(b) Use extra strength sewer tile with the joints

cemented.

(c) Use continuous metal pipe.

See Figure 11.^2, page II-9I for details,

h. Appurtenances to Tile Systems

All tile systems require certain appurtenances that are essential

to successful functioning. The various appurtenances are outlined below. These should be used and considered a part of the

specifications when applicable.

(1) Surface Inlets

Sui'face inlets should be used in low areas to remove excess

water where surface drainage is not provided. See Figure

11.29, page 11-76. Unless properly constructed, surface inlets will wash out and considerable silting of the tile line

will result. Never use surface inlets, however, if it is

possible to drain the area by means of a surface relief

ditch. This is especially necessary in areas where movement

of silt to the ponded area.and thence into the open inlet is

a problem. In these cases a blind inlet. Figure 11.28,

Ground surface

coarse grave]

259293 O - 53 - 17

FIGURE 11.28 BUND INLET TO TILE LINE
11-76

Maintain area around inlet

in sod—5'minimum radius

for sod area

^^t»W.. >^MU.,,,ll^,lflllll^'^tlll^U;n|^^|^,w„^,..,.^,,^,,^^^,.J^,,,^^,___^^^^^^^^^^_^^^^^

Riser

One I I ft. Length

One I I ft. Length

Beehive or truncate of

cone grate to fit bell of

riser size.

Sewer Pipe / i

Sewer Pipe

Drain tile above this section

JL

^

X

Direction of flow ^

Three 3' Lengths

of I I" Sewer Pipe

Drain tile

below this section

with

f T-Branch

" Spur

Two 3'Lengths of

I" Sewer Pipe

OONSTRUCTION NOTES :-

Notch out bottom of tile trench to fit

bell end of each sewer tile.

Fill all sewer pipe joints with cement

mortar and encase each joint in concrete

Tamp back fill around riser after

concrete has hardened.

COOPERATOR

COOPERATING WITH.

COUNTY

ADAPTED BY

-_SEC. .__T R.„„

_„ STATE

DATE

Use standared strength vitrified

clay sewer pipe conforming to A.S.TM.

specifications C-13

LOCATION

Line __

Station

SEWER TILE SURFACE INLET

TO TILE LINE

U.S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H.H. BENNETT, CHIEF

REGION 3 R.H. MUSSER, PI RECTOR

REFERENCE

CARTOGRAPHIC APPROVAL

DES.

;M^?

TECHNIC^i, APPROVAL

DR. CH. DATE DRAWING NO.

3'L- I74ÖG

SHEET OF

FIGURE 11.29 SURFACE INLET TO TILE LINE
11-77

should be used or a silt trap should be placed immediately

downstream from the inlet at a convenient location, Figure

11.30.

Length + 6" .

s

+

5

b1

c

Ü

r

r

Minimum 3*-0" ^ . r: ^Varioble

For combination catch basin

ond sand trap, use standord

catch basin cover or

construct grating of l"rd.

bars-3"center to center ox

other similar materlol.

For manholes use solid

cover of iron or precast

concrete.

PLAN PLAN OF GRATING

/Walls constructed of concrete,

brick, block,curved segments,

concrete tile,or vitrified bell and

spigot tile,corrugated iron pipe,

or other durable material.

Concrete base

Vitrified bell and

spigot tile,

cemented joints.

Drain tile

CONSTRUCTED IN TILE ALIGNMENT CONSTRUCTED TO ONE SIDE OF TILE ALIGNMENT

TYPICAL MANHOLE . CATCH BASIN AND SAND TRAP

FIGURE 11.30 TYPICAL MANHOLE, CATCH BASIN AND SAND TRAP

(2) Jiinction Boxes

Junction boxes should "be used where two or more mains or

sub-mains Join or where several laterals join at different

elevations. Figure 11.31, page 11-78. If the junction

Joint is in a cultivated field the box should be constructed

so that the top is at least 12 inches below the surface of

the ground. It can be capped and covered with soil and its

location referenced in for locating purposes.
11-78

.Cover of reinforced concrete or a

.steel grate

\^pip^^

^Outlet tile capacity

must equal combin

ed capacity of incoming tile lines.

The elevation of

the flow line of

outlet tile must be

equal to or below

the flow line of the

lowest incoming tile

^>SSS\SSS\SSN\\\SSS\\Si.S

AJ>V<\NSSSS\SSSSS\SS\SS>

NOTE: If tile are used for ^

making well as indicated

in sketch, they should be

ordered from factory \%-

with holes provided for

inlet and outlet tile.

ncoming tile of various sizes coming in

at different levels

and from different

sides.

FIGURE 11.31 JUNCTION BOX FOR TILE LINES

(3) Breathers and Relief Wells

Breathers or vents should be provided approximately every

1/k mile on long tile mains. They should he located where

the tile ]:nes cross permanent fences.

The primary function of relief wells is to relieve pressure

in the -Gile line that might otherwise cause it to blow out.

Relief wells should be used where the steep section of a

tile line changes to a flat section unless the capacity of

the flat section exceeds the capacity of the steep section

by 25 percent. They should also be used on lines that have
11-79

surface inlets and particularly below large surface inlets.

See Figure 11.33^ page 11-80.

{k) Tile Outlet Protection

Where tile mains outlet into an open ditch the end of the

tile should "be protected. If surface water enters the outlet

ditch at the same location as the tile, some type of structure is necessary. Where there is no surface water a section

of metal pipe at least l6 feet long should be installed with

approximately two-thirds of its length embedded into the

ditchbank, and the overhanging length discharging just

beyond the toe of the ditch slope, Figure 11.3^, page 11-81.

Swinging gates or some type of screen on all outlets should

be used to exclude rodents or other animals unless the outlet is located so that it would be impossible for rodents or

other animals to enter the tile at the outlet end. Figure

11.35, page 11T82 and Figure 11.36, page II-83. Where there

is insufficient cover at the outlet end of the tile this

condition should be handled by one of the methods shown in

Figure II.I4.2, page .11-91.

i. Estimating Tile Installation Costs

Figure 11.12 ecives the tile reauirements for different spacing.

DRAIN TILE SIZE S WEIGHT DATA

Inside Dia.

Inches

Outside Dio.

Feet

Approx. Wgt.

Der Foot

Average Wgt.

Feet/Carload

4 0.42 7# 5,700

5 0.51 1 1 3,600

6 0.59 12 3,300

8 0.79 17^2 2,000

10 0.97 271^2 1,300

12 1.17 Z7^ 930

14 1.34 47 780

15 1.43 53'/2 650

16 1.54 62^2 560

18 1.71 74 470

20 1.88 84 420

22 2.08 108 320

24 2.29 132 260

26 2.48 154 230

28 2.69 174 200

30 2.88 211 170

TILE REQUIRED/ACRE

Feet Spacing Feet Required

Der Acre

20 2,178

25 1,742

30 1,452

33 1,320

40 1,089

50 872

66 660

80 545

100 436

150 291

200 218

FIGURE 11.32 DRAIN TILE INFORMATION
11-80

-To be located in o permanent fence line or in a

protected location

Cover top with heavy wire

mesh screen or some type

of perforated cap

Ground Line—7 —1

Riser

^f^^^m^íif^f^íaímímmíjinm^^

One I I ft. length | | Sewer Pipe r—i

One I ¡ ft. length | | Sewer Pipe

K7

Fill joints with

cement mortar

Notch out bottom of tile trench

to fit bell end of T-branch L

NOTES:-

When used as a Breather the riser should

be 4"in diameter for tile lines up to and includ-

-ing l5"tile and 6"on lines over 18"

When used as a Relief Well the size of riser

should be equal to the diameter of the tile line

or one or two sizes smaller depending upon

the amount of overload.

with

T-Branch

II

Spur

COOPERATOR SEC T. „_

COOPERATING WITH

COUNTY STATE

ADAPTED BY DATE.

LOCATION

Line

Station.

BREATHER OR RELIEF WELL

FOR TILE LINES

U.S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

REGION 3

H.H.BENNETT,CHIEF

R.H.MUSSER. DIRECTOR

REFERENCE

CARTOGRAPHIC APPROVAL TECHNI.C CHNLCAL-^PPROVAL

DR. CH. DATE DRAWfNG NO.

3'L-I74<95

SHEET OF

FIGURE 11.33 BREATHER OR RELIEF WELL FOR TILE LINES
11-81

Bottom of

Open Ditch

Extend pipe to a point

perpendicular to tl>e toe

of slope or beyond unless

protected by flume or opron

Ditch Bonk

---_-_-za--

Berm Ditch Side

SpiiLBonL.

Top Land Side

PLAN Scale'{"=5"

Increase grade of outlet

pipe if necessary to reduce

height of discharge into ditch

Provide swinging

gate or iron grating

to exclude rodents

I' Mim.

Tength to be not less than ZO'

Cover gap with a

piece of tin or

heavy paper before

pouring concrete

SECTION

Note:

For detail plans of

device to exclude rodents fr^m end of pipe

see Drwg.No

Gu. yds. of concrete required for

collar.

LOCATION? MAIN_

PLAN ELEVATION

DETAIL-CONCRETE COLLAR

COOPERATOR

COOPERATING WITH

_SEC .T R

COUNTY. _ _ STATE

ADAPTED BY) ^- DATE

Note'

If ice and floating debris ore o problem

the corrugated pipe should be placed at about

a 30* angle downstream instead of outletting

perpendicularly to the stream os shown.

If corrugated pipe is placed on steeper

slope than tile,same size may be used.

Use pipe 2" larger than tile if on same

slope.

CORRUGATED PIPE OUTLET FOR TILE DRAIN

U.S.DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT, CHIC -

REFERENCE:

R.H. MUSSER.OIRECTOR

FIGURE 11.34 CORRUGATED PIPE OUTLET FOR TILE DRAIN
11-82

Thread and use 3/8" square nut or

bend end of rods at right angle

3/8" 4» rods

spaced I 1/2" o.e.

Corrugated Metal Pipe

END VIEW ELEVATION

Drill 1/2

holes in

pipe

MATERIAL

Feet of 3/8" rod

LOCATION

COOPERATOR _SEC T_ _ R._

COOPERATING WITH_

COUNTY

ADAPTED BY

STATE

DATE

GRATING FOR END OF TILE

OUTLET PIPE

U.S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H.H.BENNETT, CHIEF

REGION 3 R.H.MUSSER.DIRECTOR

REFERENCE

CARTOGRAPHIC APPROVAL TECHNICAL

DR. CH.

TECHNICAL APPROVAL

DATE DRAWING NO.

SHEET OF

FIGURE 11.35 GRATING FOR END OF TILE OUTLET PIPE
11-83

iVe/cf spo/s on rod /o k^ep

Go^c -from s//cfthg.

END VIEW SECTION A-A

PLAN

jâar er ^o//c/ /pAy/a ar-

/T^crc/^ C//P c?/'/^c?cX^.

COOPERATOR SEC...

COOPERATING WITH

COUNT*' STATE

ADAPTED BY DATE.

^ fhick,

®£ye bo/i-s J-o be we/ded

©3/Ô"Rod io be ben^

C9^ each end.

No 5co/e

„R 1

"HOMEMADE"TILE OUTLET GATE

U- S, DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT, CHIEF

REFERENCE:

CARTOGRAPHIC APPROVAL: | TECHNICAL

OSC^^

^Af/r// ^£'c/^^/

DATE

1 •24-50 3-L-^4035

FIGURE 11.36 "HOMEMADE" TILE OUTLET GATE
11-81^

By determining the n"umber of tile required per acre and by using

local costs for tile^ digging^ and laying^ a reasonably accurate

estimate of the cost per acre can be determined.

11.76 Constructing Tile Systems

a. Selecting Drain Tile

Only first-grade tile should be used in tile systems. The tile

should be free from chips or cracks that would decrease the

strength materially and when dry they should give a clear ring

if stood on end and tapped with a light hammer. The American

Society of Testing Materials has prepared specifications for

drain tile. These specifications are available upon request and

it is good practice in making purchases to stipulate that the

tile furnished meet these specifications. Either clay or concrete tile are satisfactory xinder normal soil conditions; however, under acid or strongly alkaline conditions clay tile are

generally more satisfactory since some concrete tile disintegrate

under these conditions. Concrete tile should be made with proper

proportion of cement, well graded, clean.soimd aggregate, and

water well mixed and adequately compacted. Proper curing of the

concrete after manufacture (30 days is recommended) is essential

before the tile are laid so that they have sufficient strength

to support the back fill.

b. The Tile Plan

Some sort of a tile plan should be made of every tile layout.

For very simple jobs such as single laterals or wet draws this

may be an "as constructed plan," such as Figure 11.37^ page

11-85. But where entire parts of a field are to be drained a

more economical and satisfactory installation will result if the

entire system is planned in advance. An example of a tile plan

prepared on a standard data sheet is given in Figure 11.38, pages

11-86 and II-87. The use of this data sheet will greatly facilitate preparation of plans of the smaller tile installations.

c. Equipment For Laying Tile

The tools most commonly used in trenching and laying tile by

hand are tile spades, shovel, drain scoop, and tile hook. See

Figure 11.39, page 11-88. Tile systems involving several thousand tile usually are installed by machine.

d. Laying Tile

Extreme care should be taken in staking tile lines, setting

grade stakes, placing the tile, and checking the line aftei^ards.

(1) Grade Stakes

Grade stakes should be set every 50 feet if tiling is to be

done from a string line. If string is used, a weight should
11-85

Sta»

Outlet

0/bo

1/bo

2/00

3/00

h/po

5/60

6/00

7/00

8/00

9/00

10/00

11/00

/ko

/feo

12/00

15/00

lú/oo

/20

0/00

1/00

2/00

3/00

14/00

5/00

/50

Elev.Grnd.

Ditch

U33.00

U33.OO

I433.I+5

i;33.30

1+33.U7

MAIN "A"

Elev.Grade Cut

~T^7T32-

Tile Grade

1+28.80

i+29.00

U29.2O

U29.UO

i+29.60

Í+.20

U.oo

U.25

3.90

3.87

0.20??

0.20

Ditch bottom

Tile 6»

E-W Fence

1+33.78 1+29.90 3.88 0.30

I+3I+.00 i+30.20 3.80

I+3I+.I+0 i+30.50 3.80

U3I+.65 1+30 080 3.85

Í+3I+.8O 1+31.10 3.70 f

1+35.13 1+31.1+0 3.73 0.30

1+35.80 1+31.80 i+.oo o.Uo

N-S Fence

1+35.91+ 1+32. oi+ 3.90 Junction Lat. A-l; Main A 5"

1+35.95 1+32.20 3.75 begin

1+36.20 1+32.60 3.60

U36.60 1+33.00 3.60 > f

1+36.58 1+33.08 3.50 O.i+0^ End Main A

Lateral A-l 5" T]Lie

U35.9Í+ ~1+I2.09 ~T.85 0.i;0^ Enters Main A Sta. 11;^0

1+36.31

1+36.23

1+36.27

1+36.26

1+36.05

1+36.35

1+32,1+9

1+32.53

1+32.57

1+32.61

1+32.65

1+32.85

3.82

3.70

5.70

3.65

3.1+0

3.50 0.1+0?? End Lat. A-l

B.M. #1 Cross chiseled on Top of N.E.

wingwa.ll of concrete bridge

approx. 300' S. of Dave Smith

residence. Elev. I436.I2

Note: Design based on 3/8"/2l+ hrs.

Farm Dave Smith

Sec. 3I4, T. I3N, RUW, Lucky Co., State

Tile placed June, I9I+6 —

Open dit oh=

Farm boundary fence 5

Interior fence ^X

-¥rTILE PLAN :í>.^3i^.rHi^

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT, CHIEF

REFERENCE:

CARTOGRAPHIC APPROVAL:

COMPILED:

V^MHNICAL APPROVAL:

7/i/yà L

.^^^xjun%,«gïJ~J—'j^

DRAWING NO.

FIGURE 11.37 SAMPLE TILE DRAINAGE PLAN
Bench Mark Description < Top of

/^rf^ - eosf àorner of £osf

Oo^^crétf^ /7^oc^vvùÙ of

Cortcre/as ^o>x Ccf/\^erf on

Coun^ ^oocf FT .

Moterials' ^^'of á^Corru^af'SCÍ Mefo/ P/pe

áGG'of^''S:^onc/pre^ Orar/h T/Ve

/^3o*of ^' ^ " " : "

for Gra^/hQ ^ 3" of 4^'rouncf roof

^ pf S/a' sft^ore nufsß

SPECIFICATIONS

1. Tile shall meet ASTM specifications.

2. Design based AH 3/S in./24 hrs.

3. Min. depth of tile to be sJ^

4 Average depth of loterols to be z¿

& Min. grade of loterols <^-3 ft./lOO

6. Gap between tile shall be. J/al7 Ait connections for joining Z tines must be

sealed with mortar unless manufactured

connections are used.

8. Tile shall be blinded by covering to a depth

of 6" with loose mellow top soil. All tile

laid must be blinded by end of days work.

Ä Sa^ur^ joßrm/ds/'on ondjffiec)f*caf/i>r> from Court/y

REGULAR INSPECTION OF THE TILE SYSTEM IS ESSENTIAL. PROMPT REPAIR OF ANY

FAILURE WILL KEEP THE SYSTEM IN WORKING ORDER AND MAINTENANCE COSTS LOW.

— LEGEND —

Form Bounder y _______

Permonent Fence »*-

Existing Tile Line 9—

Proposed TSIe Line • "

New Tile Installed .„.,.^,^

Existing Deep Ditch : =

Proposed Deep Ditch MMMM

Existing Shallow Ditch »—

Proposed Shallow Ditch _ i^^»

CONSTRUCTION REPORT

Dote Installed _vZé/Z7€_ /3tJ.Q^^

Contractor _j^^Jf/la7^ CQ^Tí^^^^

Staked By Q^ SOA^t. __ _^

Amount of Tile Installed úíí^lr.^

Remarks'

C/f&/3t

SECTION. j^3

TOWNSHIP _ /ÊLAL _ RANGE ¿»^J^ _

C0UNTY_41^^^if'g-— STATE_^^i^>¿. _

COOPERATOR —^Qî^'^TJ^l/ÔS

COOPERATING WITH ^J^/^^^d^jÛ^

SURVEYED BY_ Q, ^QÈ>Qjf— /E/¿.^&¿.

TILE DRAINAGE PLAN

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT, CHIEF

ORAWIVG JtIO

USE THIS SHEET FOR MINOR JOBS ONLY Ord«r blonk form by Drawing No. 3-N-2688a
2}ac

JOm

00zooImmmo>>omzo

-n

Order blank form by DrawingN

HI

00
11-88

Shovel Tile hook Drain scoop Tile spades

FIGURE 11.39 TILE DRAINAGE TOOLS

be tied to each end and hung over the support^ so that the

string is tight at all times. If the target method is used

or a tiling machine, grade stakes can "be set at 100-foot

intervals. Always have three targets set ahead of the

machine. Grade stake lines usually are offset from two to

four feet from the centerline of the tile. A method of

setting grade for hand dug trench is shown in Figure 11.40,

page 11-89.

(2) Placing Tile

In hand trenching the bottom of the tile trench should be

shaped with a drain scoop (Figure 11.39)^ so that about onequarter the circumference of the tile is laying on solid

ground. Tiling machines shape the trench properly as a part

of the trenching operation. Where tile are laid through

unstable pockets of soil use additional construction features.

Depending on the seriousness of the condition, one of the

following should be placed in the bottom of the trench

before laying the tile: stable soil, coarse hay, straw,

toiigh sod, crushed limestone, or cradle the tile. Where

cradling is used the rail and cleat method should be used as

shown in Figure 11.^1, page 11-90.

Correct methods of laying tile are given in Figure 11.26,

page 11-73. The importance of these suggestions is obvious.

(3) Protection During Construction

At the end of each day's work the end of the tile line being
11-89

d:^

ne

FIGURE 11.40 METHOD OF USING TARGETS FOR LAYING TILE

placed shall be completely closed by a wooden or metal plate

or some other device to prevent silt or debris from entering

the line in the event of rain. Upon completion of the line^

the end of the tile should be closed tightly with a plate,

brick, pieces of tile, or some other suitable material.

(k) Checking Tile

Be sure to check with a surveyor's level all flat grades, all

breaks in grades, and all turns after the tile has been
11-90

THIS NOT THIS

FIGUR£ 11.41 CRADLING TILE IN UNSTABLE SOILS

installed. Do this after the tile has "been laid and before

the trench is backfilled.

(5) Blinding the Tile

Follow specifications given in Part 11.75g(4) for blinding

tile. Never leave a line of tile exposed over night without

blinding, as surface water from a heavy rain could do considerable damage to the newly laid line. This is true even

though the tile have not been checked, as checking can be

done through the blinding material.

11.77 Maintenance of Tile Drainage Systems

Tile drainage systems do not require extensive maintenance but

the maintenance that is required is extremely important. One

broken tile will stop up an entire line. Many tile systems and

frequently parts of farms have been destroyed because of neglect

of the outlets. The outlet should be kept free at all times.

If erosion is occurring at this point, due to tile water, immediate steps should be taken to correct the situation.

11.78 Don'ts in Tile Drainage

a. Do not attempt to install a drainage system on flat lands

without surveying the lines and working from grade stakes.

b. Do not lay soft or inferior quality of tile. All tile

should conform to "American Society for Testing Materials"

specifications for farm drain tile. .^

c. Do not establish an outlet for a tile system in a ditch or

stream at such a depth that it will be submerged during ordinary

low water flow.
TILE LINE CROSSING UNDER ROAD

11-91

Rood Righi-of-\/v^ay P^rmiaaion ahau/ef be

secured in writing from

responsible react officfaf

for croseing under roae/e

with tile tíne.

JJse M&ialp'/pe, iyfra Sirengi-h sewer i-ile w'tih

Join-ts ceinenied or dram iile encased in ^"of concrete.

TILE LINE CROSSING UNDER WATERWAY OR DITCH

V/¿'\y/'x^y/AWxs?vxs^

Wofí^rway or Diich rsV/'x\'^Ay//\y/xNS^/NV/A\s?

tl I I I I I I ITTT :i I I I I I I I I I I u

JJse Me'^o/p/ps^ 5x/-ro 3frengi/7 ^e\4^&r f/M i^i/h

Join/s cemenfed ordrpin T^i/e encased in 4'ofconcrete

METHODS FOR HANDLING SHALLOW DEPTHS AT TILE OUTLET

_ To proy/afe min. co^^er __

p/ace fi//oi/er H/e //he

-A^efa/ R/pe Ou/Zer^

PROFILE.

Drain T//e O—T/Je

CROSS SELCTIOM 0? FILL

vWM\S^A^''AS'^7/(\ v/A\V7XTV>'A W//

~L&ss /ñan ?'co\/'er

~ i I I M I I 1 I I i ¿

^— Drain Tde

Use meta/pips thru secfion ^here

cover o^er file is /ess /-/tan 2 fee/-.

f/i.W^XWMWA^j.WA^AW/'AWMV^^T /^ei-a/ Pjpe OuHe-^

.y

^

3] I M l.l-Q

-Drain Tí/e

i___Ex.cava/-e a di/-ch bac/< to w/here

cai/er over fhe H/e is more f/ian 2 fee-f.

FIGURE 11.42 TILE LINE CROSSINGS AND HANDLING SHALLOW TILE OUTLETS

259293 O - 53 - 18
11-92

d. Do not extend a tile line into an open ditch without proper

protection. Either install a section of pipe or an outlet

structure. This will prevent erosion and washing of the tile

line "back into the field.

e. Do not fail to provide a "flap gate" or other adequate protection on the outlets of tile 10 inches or over in diameter.

This is to prevent animals of various sorts from hiding or denning in the line.

f. Do not lay tile in a trench with a flat bottom. The bottom

should be rounded with "drain cleaner/' a special tool to fit

the outer circumferences of the tile wall.

g. Do not make joints too tight between tiles in heavy clay

soils as all water must enter the tile at the Joints; nor should

joints be left too open in sandy or silty soils. In the former

instance joints may become sealed with clay and water will not

enter; in the latter, too much soil may enter joints and eventually fill tile lines.

h. Do not attempt, as a general rule, to join the lines

together without using special junctions called "Y's" or "T's."

Make-shift junctions formed by breaking and fitting tile together

very often leave cracks that will eventually cause holes to

appear in the fill over the lines at such junctions.

i. Do not think tile can be laid in fine sand, quicksand, or

muck, without special provisions for keeping this material out

of the tile. Only an experienced tile layer can handle construction under such conditions.

j. Do not install long lines of tile, 1,000 feet or over, without providing "vents" where the line crosses under a pemianent

fence line. Use a "T" connection in the line and cement a section

of small sewer pipe vertically into the "T." Put a heavy wire

screen over the upper end.

k. Do not construct surface inlets or junction boxes on tile

lines in open cultivated fields unless necessary, since they

create hazards to stock and the use of farm machinery, and are

a nuisance, generally.

1. Do not attempt to install a system of tile drains without

proper tools. If such work is to be done by hand, the excavation should be done with ditching spades; loose dirt or crumbs

should be removed with long-handled shovels, and the bottom of

the trench should be finished with drain scoop or "cleaner."

If several thousand feet are to be laid, a trenching machine is

desirable, as it will do the work rapidly and usually as economically as by hand labor.

m. Do not backfill tile lines with heavy subsoil clay next to

the tile, as this may tend to seal the openings between joints.
11-93

It is better to use 8 to 12 inches of topsoil^ placed immediately on top of the tile. In sand^ fine gravel, or muck, it may be

necessary to partly fill the trench with straw, weeds, or hay.

Do not use material that is too bulky as settlement will occur

in the trench when the material eventually decays.

n. Above all, do not install an expensive system of underdrains

and pay no further attention to it. For the first two or three

years after installation the lines should be inspected annually

or oftener and holes over the lines d"ug into and repairs made.

Usually a wide joint will be found at such points. A piece of

broken tile or "bat" should be placed over the crack, and the

trench carefully backfilled and tamped. Trees and brush, particularly those of water-loving nature, such as willow, cottonwood, and elm, should not be permitted to grow within kO or 50

feet of a tile line.

11.80 CULVERTS

11.81 Scope of Discussion

a. Crossings over outlet ditches and field ditches are encountered frequently in drainage ditch construction and rehabilitation. On state or federal roads, county, and even township

roads, these crossings may be bridges or large culverts of such

a size that they are beyond the scope of the farm planning

technicians. This part of the handbook is limited to a discussion of the small sizes of pipe culverts commonly used for field

road and farm lane crossings over watercourses or small open

ditches. Farm road crossings may be designed only for drainage

flow if the landowner accepts responsibility of loss of the

structxire or overflow during floods. At some locations the farm

road crossings will need to be designed for flood flows for road

protection or other purposes. The larger size farm culverts and

other types not covered by this discussion should be designed by

an engineer, as well as all culverts and bridges in connection

with all public roads or highways.

b. While the discussion in this handbook is primarily concerned

with culverts, the possibility of using a bridge type of crossing should not be ignored. Bridges are desirable in large

drainage areas with high rates of runoff, and also in relatively

flat country where loss of head must be kept to a minimum. The

bridge has the advantage of low discharge velocity and is not

as likely to clog by debris and ice. Its efficiency with

respect to drainage flow increases as the cross-sectional area

of the bridge approaches that of the ditch. Construction is

generally more difficult than for culverts, and costs are higher

for the low rates of discharge.

c. Three kinds of pipe culverts are discussed; namely, corrugated metal, bell and spigot vitrified clay tile, and concrete

culvert pipe. These are the types in common use.
11-9^

11.82 Types of Culvert Flow

a. There are many types of flow through culverts and under some

situations the design requires detailed knowledge of hydraulics.

The types of flow discussed are those commonly encountered by

farm planners, which are the two following conditions:

(1) "Where the water surface at inlet is the same elevation

as the top of the pipe culvert, and the outlet is free.

Roadway

......Mirti,, n .-i.-v^, ,. -.w.-f,',,,.,...;.. .^^,\

Ground Line

Water Surfoc« here

X equals d, and is equal or greater than d'

Fiaure 11.43 applies under above conditions

(2) Where the water surface at inlet is above the elevation

of the top of the culvert entrance and the outlet is submerged.

Roadway

Woter Surface

Ground Line

u

Flow

tch Bottom

d and d* are greater than X

Figures il.44 8 il.45 apply under above conditions

b. Where other conditions of culvert flow than those listed

above are encountered, assistance should be obtained from an

engineer in making the design.

11.83 Determining Culvert Capacity

The criteria for design of culverts for farm lanes and field

roads by farm planners are given by the examples following:

a. (1) Given: Designed drainage flow 7 cf.s.

Ditch bottom grade 0.02^

(2) Eequired: 20' - CM.P. culvert for fann road crossing

on lateral ditch

(3) Solution:

(a) From Figure 11.6, page 11-21 through 11-23a inclusive:
11-95

Ditch with i^:l side slopes would need i|-foot bottom and

1.5 depth. Then from Part 11.54b the constructed ditch

would be 2.0 feet deep.

(b) Next, from Figure 11.43, page 11-96, find that both

12-inch and 15-inch pipes are too small. An l8-inch pipe

will discharge the 7.0 c.f.s. on a slope of 1.4^. Therefore, fall in 20 foot length of culvert (C.M.P.) is 20 x

.014 or 0.3 ft. Now with bottom of ditch parallel to

ground surface, depth of ditch downstream from the culvert is 2.0 ft. + 0.3 ft. or 2.3 ft.

Farm Road

Ground Line Slope 0.02%

Elev. 100.0

Elev.99 7

Direction

_DitchjBot^

Grade 0.02%

Note that the depth of the ditch at the outlet end of

the culvert is greater than at the inlet end and is

greater than necessary for proper drainage flow. This

is because of the increased grade through the culvert

necessary to make it function efficiently.

(c) The problem illustrated above is fairly common in

the field and is applicable when the water surface at

drainage design flow in the ditch downstream from the

culvert is at or below the top (invert) of the culvert

pipe at the downstream end. Any backing up of water

downstream which would tend to cover or submerge the

downstream end of the culvert would require a different

solution. In some instances this condition can be

avoided by widening the ditch below the culvert, which

results in a lowering of the water surface at drainage

design flow. This provides the free outfall condition

upon which the preceding example was developed.

b. (1) Given: Designed drainage flow 10 c.f.s.

Ground line and ditch bottom grade 0.02^

Minimiam depth lj.,o ft.

Max. velocity (due to soil

conditions) 5 ft. per

second

(2) Eequired:

(3) Solution:

20 ft. C.M.P. culvert for farm road crossing

on lateral ditch entering main ditch h foot

deep.

(a; Prom Figure 11.6, page 11-21 to ll-23a inclusive
11-96

CORRUGATED METAL PIPE-FREE OUTLET

CAPACITY IN Cubic Feet per Second

DIAMETER

OF PIPE

IN INCHES

SLOPIE IN PEI^ CENT

.1 .2 .3 .4 .5 .6 .8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4

12 0.6 1.0 1.3 1.5 1.7 1.9 2.1 2.3 24 2,5 2£ 2.6 2.6 2.6 2.6

15 1.3 2.0 24 2.8 3.0 3.3 3.7 4.0 4.3 4.4 4.5 4.6 4.6 4.6 4.6

18 2.1 3.1 3.9 44 4.9 54 6.1 6.5 6.8 7.0 7.1 7.1 7.1 7.1 7.1

21 „ 3.3 4.7 5.9 6.8 7.5 8.1 9.0 9.6 10 10. 10. II. II. II. II.

24" 47 6.8 8.3 9.5 10. II. 13. 14 14 15. 15. 15. 15. 15. 15.

30 8 12 15 17 19 21 23 24 25 25 26 26 26 26 26

36 12 19 25 28 31 33 37 39 40 40 40 40 40 40 40

42 20 30 37 42 46 50 55 57 59 59 59 59 59 59 59

48 25 42 53 62 68 72 77 80 82 83 83 83 83 83 83

54 36 57 72 83 90 97 100 110 110 lio 110 NO 110 110 110

60 47 77 97 110 120 130 140 140 50 150 150 150 150 150 150

4 6 8 10

SMOOTH PIPE-FREE OUTLET

CAPACITY IN Cubic Feet per Second

DIAMETER

OF PIPE

IN INCHES

SLOPE IN PER CENT 1

.1 .2 .3 .4 .5 .6 .8 1.0 1.2 1.4 1.6 1.8 2.0 i 2.2 2.4

12 1.2 1.8 2.2 2.3 24 2.5 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6 2.6

15 2.1 3.2 3.8 4.1 44 4.5 4.6 4.6 4.6 4.6 4.6 46 46 4.6 4.6

18 3.5 5.0 5.9 6.5 6.8 7.0 7.1 7.1 7.1 7.1 7.1 7.1 7.1 7.1 7.1

21 5.4 7.6 8.9 9.7 10 10. II. 11. 1 1. 1 1. 1 1. 1 1. 1 1. 1 1. 1 1.

24 7.5 10.8 12.8 13.9 144 15. 15. 15. 15. 15. 15. 15. 15. 15. 15.

30 « 14 19 23 24 25 26 26 26 26 26 26 26 26 26 26

36^ 22 31 37 39 40 40 40 40 40 40 40 40 40 40 40

42 34 47 54 58 59 59 59 59 59 59 59 59 59 59 59

48 50 67 77 83 83 83 83 83 83 83 83 83 83 83 83

54 70 95 104 108 110 110 110 110 110 MO 110 110 no 110 1 10

60 90 125 137 142 145 150 150 150 150 150 150 150 150 150 150

14 6 8 1

NOTE: The v

at the appro

discharge re

The "stairs

the upper le

indicate app

feet per sec

Reference: F

aiues in bold face type indicate discharge ^^^momm^^

imate "critical slope' beyond which the ^..sé'^'^^

mains constant for any given size culvert. ^^as«^^ ^^i Headwater

of heo

ft and r

roximat

ond.

{egiona

vy hor

eoding

e veloc

Drawif

zontal

downw

ities of

igs 3-L

lines be

3rd and

2,4,€

-7279

îgmninç

to the

>,8, and

and 3-

at

right

10

L-728C)

Crit

Crit

Max

D = i

n = C

ical ve

ical slo

imum t

líamete

).0I5 S

ocity ir

pe in p

ischarg

r of pip

mooth p

1 feet p

ercent =

e in c.f

e in fe

ipe, n =

er sec.

S= -La ° 0 1/

.s. = Q =

et

0.021

= V= 4.475 NTF"

'1.58 D^^^

Corrugated pipe

FIGURE 11.43 CAPACITY OF PIPE WITH WATER SURFACE AT INLET THE SAME ELEVATION AS THE TOP OF

PIPE AND FREE OUTLET
11-97

SQUARE CORNERED ENTRANCE CAPACITY

Cubic Feet per Second

ENTRANCE,

^

''ÍW////////A

mmm

DIAMETER

OF PIPE

IN INCHES

1 AREA

OF PIF»E

SQ.FT

HEAD ON PIPE IN FEET - - - -

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.5

12 0.79 1.3 1.8 2.2 2.5 2.8 3.0 3.3 3.5 3.7 3.9 4.3 4.6 49 5.2 5.5 5.8 6.1 6.3 6.6 6.8 7.0 7.2 7.3

15 1.23 2.1 2.9 3.5 4.0 4.5 4.9 5.4 5.7 6.1 6.4 7.1 7.6 8.1 8.6 9.0 9.5 9.9 10 II II II 12 12

18 1.77 3.1 4.3 5.3 6.1 6.8 7,4 8.1 8.6 9.2 9.7 II II 12 13 14 14 15 15 16 17 17 18 18

21 2.40 4.3 6.0 7.3 8.4 9.5 10 II 12" 13 13 15 16 17 18 19 20 21 21 22 23 24 25 25

24 3.14 5.7 8.1 9.8 II 13 14 15 16 17 18 20 21 23 24 25 26 28 29 30 31 32 33 33

30 4.91 9.1 13 16 18 20 22 24 25 27 28 31 33 36 38 40 42 44 46 47 49 51 52 53

36 7.07 13 19 23 26 29 32 35 37 39 41 45 49 52 55 58 61 64 67 69 72 74 76 77

42 9.62 18 25 31 35 40 43 47 50 53 56 62 66 71 75 79 83 87 91 94 97 101 104 105

48 12.57 24 33 40 46 52 57 62 66 70 74 81 87 93 99 104109 114 118 123 127 132 135 138

54 15.90 30 42 51 59 66 72 78 83 88 93 102 no 117 124 131 137 144 150 155 161 166 171 174

60 19.63 37 52 63 72 82 88 97 102 109 115 126 135 145 154 162 170 178 185 192 199206211 215

3 4 5 6 8 10

ELEVELED LIP ENTRANCE UPSTREAM CAPACITY

Cubic Feet per Second c^xo^^.c^--^ ENTRANCE

'mmm

W//////À

DIAMETER

OF PIPE

IN INCHES

AREA

OF PIPE

SQ.FT.

HEAD ON PIPE IN FEET

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.5

12 0.79 1.3 1.8 2.3 2.6 2.9 3.2 3.5 3.7 3.9 4.1 4.5 4.9 5.2 5.5 5.8 6.1 6.4 6.6 6.9 7.1 7.4 7.6 7.7

15 1.23 2.2 3.1 3.7 4.3 4.8 5.2 5.7 6.1 6.5 6.8 7.5 8.0 8.6 9.1 9.6 10 11 II 11 12 12 13 13

18 1.77 3.3 4.7 5.7 6.5 7.4 8.0 8.7 9.2 9.8 10 11 12 13 14 15 15 16 17 17 18 19 19 19

21 2.40 4.6 6.5 8.0 9.1 10 II 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 27

24 3.14 6.2 8.7 II 12. 14 15 16 17 18 19 21 23 24 26 27 29 30 31 32 34 35 36 36

30 4.91 10 14 17 20 23 25 27 28 30 32 35 38 40 43 45 47 49 51 53 55 57 59 60

36 7.07 15 21 26 30 33 36 39 42 45 47 52 56 59 63 66 70 73 76 79 81 84 87 88

42 9.62 21 29 36 41 46 51 55 58 62 66 72 77 83 88 93 97 101 106 109 113 117 121 122

..48 12.57 28 39 48 55 62 67 73 77 82 87 95 102 109 116 122 128 134 139 145 150 155 159 162

54 15.90 36 50 61 70 79 86 93 99 105 III 122 131 140 149 156 164 172 179 185 192 199 204 206

60 19.63 43 62 76 87 98 107 116 123 131 138 152 163 174 185 195 ^04 214223 232239 248254 259

3 4 5 6 8 10

NOTE: Based on Yarnell,Nqgler,Woodward experiments. University of Iowa.

50 foot length of pipe used in computations.

See Figure 86 for critical slopes.

Dark lines across chart indicates velocities of

3-4-5-6-8-10 feet per second.

Compiled by RJ. 1-7-48

Revised 2-25-53 Checked by H.W.R 3-8-4€

FIGURE 11.44 CAPACITY OF CONCRETE CULVERTS 20 TO 40 FEET IN LENGTH WITH SUBMERGED OUTLET
11-98

Ditch with 2:1 side slopes, and k foot bottom width

would flow 2 feet deep. However, as this lateral ditch

outlets into main ditch k foot deep, construction

dimensions of lateral ditch would be k foot depth, k

foot bottom, with 2:1 side slopes.

(b) Now from Figure ll.i^3 note that 18 inch CM.P. has

maximum capacity of 7.1 c.f.s., which is not sufficient

for the given situation. Therefore this size culvert

will have to "head up," which means the entrance will

be submerged.

(c) Now using Figure 11.^5, page 11-99, find that to

discharge the given 10 c.f.s. the 18 inch CM.P. culvert requires a head of 1.6 feet. This means that the

elevation of the water surface at the upstream end of

the culvert needs to be 1.6 feet above the water surface at the outlet end of the culvert. Therefore, the

culvert is operating under a "submerged condition."

The problem can be illustrated as below.

Elev. 104.00

Roodwoy

Ground Line Slope 0.02%

Elev. 100.00 Elev.99.96 0.02%

(d) Also, it should be noted from Figure 11A5 that

when the 18 inch CM.P. discharges the 10 c.f.s. under

a head of 1.6 feet, the discharge velocity is almost 6

feet per second. This is a rather high velocity, and

unless a special channel lining were to be used below

the culvert, the solution arrived at does not meet our

given condition of a maximum allowable velocity of 5

feet per second.

(e) Further, it should be noted from the above sketch

that when the required head of 1.6 feet is reached, the

water surface at the inlet is slightly less than 0.5

foot below the ground line, which in this example may

be all right. However under some field conditions, in

order to provide the required head, the water surface

at the inlet may reach the ground line or even flood

over. Naturally such a solution is not acceptable.
11-99

CORRUGATED METAL PIPE CAPACITY

Cubic Feet per Second

DIAMETER

OF PIPE

IN INCHES

AREA

OF PIPE

SQ. FT.

HEAD ON PIPE IN FEET

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.5

12 0.79 1.0 1.4 1.7 1.9 2.1 2.3 2.5 2.7 p2?. 30 3.3 35 3.8 4.0 4.2 4.4 4.6 4.8 5.0 5.2 5.4 5.5 5.6

15 1.23 1.7 £^ 2.9 3.3 3.7 4.0 44 4.6 5.0 5.2 5.7 6.2 6.6 70 7.4 7.7 8.1 8.4 8.7 9.0 9.4 9.6 %1

18 1.77 2.5 3.6 4.4 5.0 5.6 6.1 6.7 7.1 7.5 7.9 8.7 9.4 10 11 11 12 12 13 13 14 14 15 15

21 2.40 3.6 5.1 6.3 7.2 8.1 8.8 9.6 10 II II . 12. 13 14 15 16 17 18 18 19 20 20 21 21

24 .3.14 5.0 7.0 8.6 9.8 II 12, 13 14 15 16 17 18 20 21 22 23 Z± ?5 26 27 28 29 29

30 4.91 8.2 12 14 16 18 20 22 23 24 26 28 30 32 34 36 38 40 41 43 44 46 47 48

36 7.07 12 17 21 24 27 30 32 34 37 39 42 46 49 52 54 57 60 62 64 67 69 71 72

42 962 17 24 30 34 38 42 45 48 51 54 59 64 68 72 76 80 84 87 90 93 97 99 101

48 12.57 23 32 39 45 51 55 60 64 68 71 79 84 90 96 101 106 1 1 1 115 119 124 128 132 134

54 15.90 29 41 51 58 65 71 77 82 87 92 101 108 116 123129 136 142 148 153 159 164 169 172

60 1 9.63 37 52 63 72 82 88 96 102 109 115 126 135 145 154 162 170 178 185 192 199I2O62II 215

2 3 4 5 6 8 10

VITRIFIED CLAY PIPE BELL

UPSTREAM CAPACITY

Cubic Feet per Second

DIAMETER

OF PIPE

IN INCHES

AREA

OF PIPE

SQ.FT

HEAD ON PIPE IN FEET

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.5

12 0.79 1.6 2.2 2.6 3.0 3.4 3.7 4.0 4.3 4.6 4.8 5.3 5.7 6.1 6.5 6.8 7.1 7.4 7.7 8.0 8.3 8.6 8.9 9.0

15 1.23 2.5 3.6 4.3 5.0 5.6 6.1 6.6 7.0 7.5 7.9 8.7 9.3 9.9 11 1 1 12 12 13 13 14 14 15 15

18 1.77 3.7 5.2 6.4 7.3 8.3 9.0 9.8 10 11 12 13 14 15 16 16 17 18 19 19 20 21 21 22

21 2.40 5.1 7.2 8.8 10 11 12 13 14 15 16 18 19 20 22 23 24 25 26 27 28 29 30 30

24 3.14 6.8 9.6 12 13 15 16 18 19 20 21 23 25 27 28 30 31 33 34 35 37 38 39 40

30 4.91 11 15 18 21 23 25 28 29 31 33 36 39 42 44 47 49 51 53 55 57 59 61 62

36 7.07 15 21 26 30 34 37 40 42 45 48 52 56 60 64 67 71 74 77 80 83 85 88 89

42 9.62 21 29 35 40 45 49 54 57 61 64 70 76 81 86 90 95 99 103 107 111 115 118 120

48 12.57 26 V 45 52 59 64 69 74 78 83 91 98 104 111 116 122 1,26 133 138 143 148 152 154

54 15.90 33 46 56 64 72 79 86 91 97 102 112 120 128 137 144 151 158 164 170 177 183 188 191

60 19.63 39 55 68 77 87 95 103 109 117 123 135 145 155 165 173 182 191 198 205 212 220226230

3 4 5 6 8 10

NOTE: Based on YarnelljNagler, Woodward experiments. University of Iowa.

30 foot length of pipe used in Computations,

See Figure 86 for critical slopes.

Dark lines across chart indicates velocities of

2-3-4-6-6-8-10 feetper second. Compiled RJ.-I-7-48

Revised 2-25-53 Checked H.WF-3-8-48

FIGURE 11.45 CAPACITY OF CORRUGATED METAL PIPE AND VITRIFIED CLAY PIPE 20 TO 40 FEET IN LENGTH

WITH SUBMERGED OUTLET
11-100

(f) Also^ when the water level is "heading up" at the

culvert entrance, the velocity of the water in the

ditch upstream is very slow, and the ponding extends a

considerable distance upstream. This is an undesirable

situation, as any silt load in the drainage flow will

tend to deposit in the ditch bottom. In time, capacity

will be lost, and a cleanout job is necessary.

(g) The next step in arriving at a solution is to try

a larger culvert size. Referring again to Figure 11.^3^

note that a 2k inch CM.P. has a capacity of 10 c.f.s.

on a slope of 0.5^, with velocity of less than k feet

per second. This then is the same type of situation

covered in example "a." While this solution calls for

a design of a 2k inch culvert which is a Class D job

(Reg. Memo 60), it points out that the farm planner can

make the design, but needs the approval only of a

qualified engineer to go ahead with the job.

c. In applying the above criteria keep in mind that it applies

to farm roads and field lanes and it does not apply to culverts

and bridges for township, coionty, state, or federal roads. These

large size structures should be designed by an engineer.
12-1

PAET 12

lERIGATION

12.10 GENERAL

The information contained in this part is intended to give a basic

concept of the place of irrigation in developing the farm conservation plan. By enijmerating some of the needs for, and methods of

accomplishing irrigation, it is hoped that proper recognition can be

given to this practice where it is applicable. It is not intended

that the information given herein will enable one to design an irrigation system. That responsibility rests with engineering-trained

personnel in accordance with current policy (Regional Memorandiim #60)

The material covered does provide sufficient information so that

irrigation needs (short of actual system to apply water) can be

discussed intelligently with farmers. For more detailed information

refer to USDA Fanners* Bulletins Nos. 18^6 (Supplemental Irrigation)

and 1922 (Practical Irrigation).

12.11 The Need For Irrigation in the Humid Section

a. Conservation irrigation on the farm is simply the use of the

irrigation and cropping methods that best fit the particular

soil, slope, crop, and water supply. It makes possible irrigation without erosion damage, waterlogging, or undue water loss.

Supplemental irrigation, as the name indicates, means the artificial watering of crops in areas where rainfall is ordinarily

depended upon to furnish the necessary moisture. Even in areas

of this kind, periods of one, two, or three weeks occur in which

rainfall is not sufficient and artificial applications of water

will be of great benefit. This application of additional water

is then called supplemental irrigation.

b. A study of the rainfall pattern of the hiomid section gives

reasons why supplemental irrigation is of importance. The probable average number of periods of deficient rainfall per year

are:

State* 1 t0 2 weeks 2 toA week?

Illinois 6 periods 1 period

Indiana 6 1

Iowa 8 1

Michigan 7 1

Minnesota 6 2

Ohio 5 1

Missouri Figures not available

Wisconsin tt tt 11

*Froin "Electric Power for Irrigation in the Humid Region," published by Conmittee on the

Relationship of Electricity to Agriculture, 11017* No. 2*
12-2

Periods of deficient rainfall refer to those periods when the

rainfall is insufficient to meet the needs of the crop being

grown. While various crops require different amounts of water,

the average needs will approximate 1 inch per week.

In the humid region, studies in 18 states indicate further:

Once in seven years, a period of six weeks occurred in

which precipitation was less than one-quarter inch.

Once in two years, a like period of four weeks or more

occurred.

c. For any locality, information on need for supplemental irrigation can be made by a study of local rainfall records for the

months of May, June, July, August, and September, with special

emphasis on underJLined months. For ordinary conditions for maximum crop production, one inch of water for every seven days is

required. For rains of more than one inch in a 2ii-hour period,

a large portion may be lost by runoff and cannot be considered

available for crop production.

d. The application of water by means of supplemental irrigation

has many benefits beyond the prime one of insuring a crop. Optimum moisture conditions such as can be obtained by irrigating,

usually assure better seed germination. Better quality crops,

as well as increased yields, are obtained by eliminating any

short periods of drought which might occur because of deficient

rainfall. Frost control for crops growing in low-lying pockets

is another benefit which can be obtained by the use of a properly

designed sprinkler irrigation system. Protection through a long

period of very low temperature cannot be hoped for, and further

in a long, cold spell, even of only moderate intensity, damage

from broken stems and branches due to accumulating ice load may

be as harmful as possible frost damage. Protection is obtainable

only on the area that can be watered at one time during the

entire frost period.

12.12 Physical Aspects of Irrigation

a. Effect of Soil Types on Irrigation

The table following shows the relation of soil texture and

organic matter content to the permeability and water-holding

capacity. Unless these relationships are clearly understood by

the Irrigator, damaging or wasteful water application may result.

Care must be exercised that water is not applied too rapidly or

in too great a quantity. In addition to being wasteful, harm may

be done to growing plants due to a water-logged soil.
12-3

COMPARISON OF PHYSICAL AND WATER-HOLDING PROPERTIES OF SOILS

Dept») of Soil

Permeability Water Holding Wetted by One

Texture (Incites Water Capacity (Incites Inch of Water

of Soil Per Hour) Per Foot of Deptit) (Incites)

Very light 1.5 to 2.0 0.2 to 0.6 60 to 20

Light 1.0 to 1.5 0.6 to 1.2 20 to 10

Mod. light 0.6 to 1.0 1.2 to 2.0 10 to 6

Medium 0.25 to 0.6 2.0 to 2.5 6 to 5

Mod, heavy 0.15 to 0.25 2.0 to 2.5 6 to 5

Heavy 0.05 to 0.15 2.0 to 2.5 6 to 5

Very heavy 0.01 to 0.05 1.9 to 2.1^ 6 to 5

Peat & muck •f 3.0 k

Note: Eange due to low, and medium to high organic matter content,

b. Water Requirements

The amount of water required to produce a poimd of dry matter

varies with the crop grown. The table below shows the result of

some research work on this subject in Wisconsin.

WATER REQUIREMENTS FOR SOME COMMON FIELD CROPS

Lbs. Water Per Lb. Needed For Yield Shown

Crop Dry Matter Produced Yield Incites

Alfalfa 8kk k T/Ac. 28

Corn 350 75 Bu./Ac. 1^

Oats 583 60 " " 12

Wheat 557 30 " " 11

Barley 518 ko " " 10

Soybeans 6k6 20 " 8

Potatoes ItOO " 1^0

c. Working Depth^ Eoot Zone

The depth to which plant roots will penetrate the soil in search

of plant food and moisture under normal conditions deteniiines the

depth to which any crop should be irrigated. It follows that

this depth will influence the amount of water that would be

applied at each irrigation. If the soil is wetted to less than

the working depth of the root zone, more frequent wetting is

necessary. This involves needless additional labor and expense.

If the soil is wetted below the working depth of the roots, this

of course is a waste of badly needed water, may result in leaching of plant nutrients, and results in needless pumping costs.

The following table lists some common crops which might be irrigated, showing working depth of root zone and peak daily use of

soil moisture.
12-4

ROOT WORKING DEPTHS AND VALUES OF PEAK DAILY USE

OF SOIL MOISTURE FOR OPTIMUM YIELDS OF COMMON IRRIGATED CROPS

Peak Daily Use of Soil Moisture

Working Depth

Root Zone

(Acre-lriclies Per Acre Per Day)

Cool \) Moderate If Hot 3/

Crop (Feet) Ct imate Climate CI imate

Alfalfa 3.0 0.15 0.20 0.25-0.30

Apples (cult.) 5.0 0.15 0.20 0.25

Apples (cover crop) 5.0 0.20 0.25 0.30

Beans, bush 3.0 0.12 0.15 0.20

Cherries (cult.) i^.O 0.15 0.20 0.25

Cherries (cover crop) 4.0 0.20 0.25 0,30

Corn, field 3.0 0.12 0.15 0.20

Corn, sweet 2.0 0.12 0.15 0.20

Cucumbers 3.0 0.10 0.12 0.li^

Garden root crops 2.0 0.10 0.12 0.11^

Grain 3.0 0.15 0.20 0.22

Pasture, bluegrass 1.5 0.12 0.16 0.20-0.25

Potatoes 1.5 0.10 0.12 0.14

Raspberries 2.5 0.10 0.12 0.14

Eed clover 3.0 0.15 0.20 0.25-0.30

Strawberries 1.0 0.10 0.12 0.14

Sugar beets 3.0 0.12 0.15 0.20

Tomatoes 3.0 0.10 0.12 0.14

1/ Cool to moderate ^bemperatiires - kO° to 55°F

2/ Moderate temperatures - 55° to '750p

3/ High temperatures - 75° to 95°F

d. When to Irrigate

When a soil's moisture is depleted to the extent that no moisture

is available for plant growth, the soil has reached its wilting

point. The object of supplemental irrigation is to apply water

at the proper time to prevent the soil from reaching this point,

thus preventing a retardance or complete cessation of plant

growth. In order to determine when water needs to be applied,

some practical method of measuring the amount of soil moisture

available for plant growth must be used.

One method, and perhaps the most reliable, is to use plaster of

paris electrical resistance blocks which have been buried in the

soil at various depths. For a shallow-rooted crop, blocks should

be buried at depths of about k to 10 inches, while for deeperrooted crops, blocks should be placed about 6, 12, 24, and

possibly 36 inches in depth. The blocks are equipped with lead

wires, to which a moisture meter is connected to give a direct

recording of the percent of moistxire in the soil. (Moisture

capacity in blocks will equalize itself with soil in a period of

2k hours.)
12-5

Another method^ less scientific, with which fairly good results

may be obtained, relies entirely on the "feel" of the soil.

Samples of the soil would be taken from the depths indicated in

the paragraph preceding. The sample of soil is squeezed in the

hana and the resulting evidences of moisture are noted. The following table gives the criteria for determining moisture conditions by the "feel."

DETERMINATION OF SOIL MOISTURE BY THE "FEEL" METHOD

Degree of

Moisture Feel

Amount of

Moisture

Dry Powder dry. None

Low Crumbly^ will not hold together. 25^ or less

(critical)

Fair Somewhat crumbly^ but will hold together. 25 to 50^6

Good Forms ball; will stick slightly with

pressure.

50 to 75^

Excellent Forms a ball and is pliable; sticks

readily; a clear water sheen will come

to the surface when ball is squeezed in

the hand.

75 to 100^

Too wet Can squeeze free water. Over field

capacity

Regardless of the method used, it is essential that the Irrigator

have some means available which will enable him to determine if

water is needed. The Michigan Experiment Station recommends that

water be applied on light soils when the moisture capacity is

down to about 50^ of the field capacity; whereas, on medium

textured soils water should be applied when the soil is at about

35^ capacity. Field capacity is the amount of water a soil will

hold after all free (gravitational) water has been removed. The

figures given are not arbitrary. In all cases the time at which

irrigation is to start will have to be determined by such factors

as the irrigation frequency, size of area to be irrigated, capacity of irrigation system, etc.

e. Is the Water Supply Adecúate?

One of the common mistakes made in practicing irrigation is trying to irrigate too much land with too little water. The water

supply should be great enough to irrigate crops during a prolonged dry period. There is no point in irrigating a large

acreage half-way through a drought period and then allowing your

crops to suffer from a water shortage. If the water supply is

not large enough for the acreage desired, then this acreage must

be reduced. Before investing money in irrigation equipment, the
12-6

Irrigator should make certain that he has enough water for his

contemplated irrigation operations. If a pond is used^ it must

be large enough to store all of the water needed during the

irrigation season, plus evaporation, and seepage losses. Drainage area must be large enough to replenish supply for next irrigation season.

Krimgold and Minshall,-^ in analyzing evaporation losses from

ponds in four zones of the claypan areas, found net losses

(evaporation minus precipitation on pond area) of from 1^ to 36

inches for the 5-nionth period of May through September. Obviously this loss, in addition to that from seepage, which may run

from 2 to 12 inches, is an important factor in the net amount of

water available for irrigation purposes.

f. Fertilizer Application

Any water soluble fertilizer is easily applied to the land through

sprinkler irrigation methods. The area on which water is being

applied at any given setting can be determined and from this

figure the desired amount of fertilizer to be distributed for

each setting can be calculated. The depth to which fertilizer

is to be placed can also be controlled by introducing the fertilizer into the distribution system at the proper time. If deep

penetration of the fertilizer is desired, it will be allowed to

enter the sprinkler system at the beginning of the sprinkling

period. Conversely, if it is desired to have the fertilizer

placed near the surface of the soil, it will be applied near the

end of the period. It is not considered practical to apply

phosphorous fertilizers through the irrigation system because of

losses due to fixation.

12.20 WATER SUPPLY

12.21 Types of Water Supply For Irrigation

a. Streams or lakes, shallow.wells,'deep wells, and farm ponds

are the usual sources of water. The water supply should be near

the field to be irrigated in order to avoid expensive supply

lines. The cost of pumping will generally be low if the water

can be obtained from a stream, lake, or shallow well where it

can be used without pumping any great distance. Deep well

installations are usually expensive and the cost of pumping may

be excessive.

b. In the Upper Mississippi Valley Region not every farmer has

an adequate supply of water available for extensive irrigation.

Therefore, supplemental irrigation of large tracts is likely to

be limited to those farms having a natural stream, large pond,

or an abundance of underground water close to the surface for

shallow well pumping. However, there are many opport-unities for

the irrigation of small tracts of one-half to two acres of truck

^Hydraulic Design of Farm Ponds and Rates of Runoff for Design of Conservation Structures in

the claypan areas. SCS-1P*56, May 1945«
12-7

or garden crops which produce high income per acre. The total

water needs for these smaller areas are relatively low and often

the need may be supplied by the farm water supply system or by

an inexpensive supplemental source which can be developed.

Small electric pumps^ windmills, overhead storage tanks, all

have possibilities for use in irrigating these small tracts,

c. Water Rights For Irrigation Purposes

When water for irrigation piirposes is pumped from a natural

stream or lake, the state laws governing use of such water

should be explored. Some states have definite regulations

relative to the damming and use of water from streams. Some

states require permits before ground water can be pumped when

the quantity exceeds a specified amount. In the absence of

statutory provisions, it is often the custom to initiate a water

right by filing a notice of the intent to divert water and

recording this action in the county record.

12.30 GENERAL TYPES OF lEEIGATION

12.31 Gravity Irrigation (Flooding)

a. Basin Irrigation

The purpose of this method is to fill a diked area of land with

water to the desired depth quickly and allow the water to go

into the soil. When basins are properly graded and built to the

right dimensions for the kind of soil and the water supply,

water can be applied efficiently.

b. Border Irrigation

This is a controlled way of flooding the surface of a field. The

idea is to advance a sheet of water down a narrow strip between

low ridges or borders and to get the water into the soil as the

sheet advances. It requires that the strip be well leveled

between the border ridges and the grade down the strip be fairly

uniform to avoid ponding. The ridges should be low and ro\mded

so they can be planted with the strips. Then no land is taken

out of production.

c. Contour or Bench Border Irrigation

This method is adapted to fairly uniform moderate slopes with

deep soils. The strips are laid out across the slope on a controlled grade and the ridges are constructed parallel to each

other.

d. Corrugation Irrigation

In this method the water is applied in small furrows. It then

moves laterally through the soil between the furrows to wet the

entire area. The method is designed for heavy soils that take

water slowly and that seal over and bake when flooded.

259293 O - 53 - 19
12-8

e. Furrow Irrigation

Furrow irrigation is a method of irrigating row crops. The

water is applied in the furrows between the plant rows. Many of

the present furrows are too steep for safe irrigation. This

fact has been the greatest single cause of erosion by irrigation

water. Because cultivation to control weeds keeps the soil in

the furrows loose, it is easily eroded.

f. Contour-Furrow Irrigation

This is the method of applying water in furrows across rather

than down sloping land. The furrows are given just enough grade

for water to flow, but not enoiigh to cause soil washing. There

is a "critical" furrow grade for each irrigable soil. Below the

"critical" grade it is safe to apply any size stream of water

that the furrow will hold without causing erosion in the furrow.

Deep-furrow row crops can be irrigated safely by the contourfurrow method on cross slopes up to about 8 percent.

g. Broad-Furrow Irrigation

On slopes not exceeding 3 percent for most soils, the use of

broad-bottom furrows in place of the usual narrow V-type furrow

will increase the rate of water intake and reduce furrow erosion.

This method is recommended for orchards planted on contour

benches as a means of eliminating erosion resulting from grade

variation along the benches.

h. Controlled Floodings

In this method, water is flooded down slope between closely

spaced field ditches which keep the water from concentrating and

causing erosion. Frequent openings in the ditches allow a uniform distribution of water over the field.

12.32 Sub-irrigation or Controlled Drainage

This is usually used in connection with controlled drainage of

peat, muck, or sandy soils. It may be accomplished by tile or

ditches with water table height controlled by outlet structure

in main outlet. Water is actually supplied to cropland from outside source by seepage, pumping, or gravity flow.

12.33 Sprinkler Type Irrigation

a. This method of irrigation adapts itself well to varied conditions existent in this region. Water may be applied with

sprinklers at a rate which the soil will absorb without runoff.

Sprinklers can be turned off when the soil has absorbed the

right amount of water for the crop needs. Water can be applied

uniformly on land of imeven topography, thus eliminating the

need for land leveling operations. Evaporation losses are

usually high, particularly in hot, windy climates. On heavy
12-9

soils, because of the low permeability, the rate of applying

water may be so low that much of it is evaporated before it

enters the soil.

b. Several types of equipment are available for applying water

by the sprinkler method. Perforated pipe, overhead oscillating

pipe and portable rotary spray are the common types. The overhead oscillating type, which is a fixed installation, is particularly adapted to nurseiy and small truck crop needs. Portable

rotary spray systems are suitable for larger acreages. Overhead

and portable rotary spray systems are illustrated in Figure 12.1,

page 12-10,

12.14-0 ADAPTATION OF TYPES OF lEEIGATION SYSTEMS TO THE EEGION

12.41 Gravity irrigation is particularly adapted to relatively flat

uniform slopes of medium- to heavy-textured soils. Flat lands

requiring surface drainage can often be irrigated with a combination irrigation and surface drainage system. Small flat areas

in hilly country may be irrigated by gravity methods using a

farm pond as the source of water. It should be kept in mind

that all types of gravity irrigation systems require relatively

large amounts of water at the outset in order to get the flooding action needed for uniform coverage of the area to be watered.

12.1|-2 Sub-surface Irrigation

Best adapted to peat, muck, and sandy soils. Where the permanent water table or an impervious layer lies several feet below

a highly permeable surface soil, successful sub-irrigation can

be accomplished by holding water in parallel ditches or tile

lines until the water table over the whole area has been raised

almost to the ground surface. The water is then allowed to

drain from the ditches and the water table gradually falls to

its original position.

12.14-3 Sprinkler Type Irrigation

a. Overhead Pipe System

The overhead pipe system is commonly called the oscillating

sprinkler system of overhead irrigation. It is well suited to

growing truck crops on small areas under ten acres and particularly for areas of about two, acyes where the crops grown are

lettuce, spinach,, cauliflower, and berries -which may be injured

by a heavy spray. The first cost of installation of this system

is high, but the installation is permanent and it can be operated with very little labor. Similar to the portable pipe system,

it can be used on an irregular tract without ground leveling.

The permanent uprights somewhat impede field operation and are

objectionable particularly in ordinary field crops or truck crops

grown on an extensive scale. The length of pipe varies from 100

to 700 feet and operating pressures vary from 20 to 50 pounds

per square inch. Ordinarily pipes are spaced 50 f^et apart.

Nozzles are installed on pipes at intervals of three to four

feet so that all are in one plane. See Figure 12.1, page 12-10.
o

c

3]

m

:3

z

mX

>

^'Wwi.iiUMtfi. I Wllü>tfi|.!l ' . tH^;ff*'g^y^!"' 7'.:-"j«^.-j-f'o a.'a...-j-¿..!-¿M

- i:í«ií^ ^

.. .» »* "^ 1

z^^:..

. -li

A- J

PERMANENT OVERHEAD « ;*•' '-^^ M -S>s;¿'

•^ SPRINKLER SYSTEM ,, '.■■ v

tí

From'Supp'ementol Irnggtion" bj tcurtesyof Johns-Monville
12-11

b. Perforated Pipe

A system of 3-, ^1--, and 5-inch diameter light-weight pipe

connected by easily Joined slip joints. Low pressures, ranging

from k to 15 pounds per square inch, are used. Under the 15

pound pressure, if conditions are favorable, a strip of ground

30 feet wide or more (15 feet each side of pipe) may be wetted

at one setting. Water is usually applied at a rate of one-half

inch or more per hour, limiting its use to the more permeable

soils. Since pipe spacings are close, the acreage irrigated

will be rather small, unless a large qioantity of pipe is available.

FIGURE 12.2 IRRIGATION BY PERFORATED PIPE
12-12

c. Portable Eotary Spray System

(1) Medium pressure, 20-50 pounds per square inch

This system usually consists of a main line running from the

pump at the source of water to the field or fields which are

to be irrigated. Lateral lines with sprinkler heads spaced

from 20-60 feet are connected to the main at intervals from

40-80 feet across the field. Since the lateral lines are

usually made of lightweight pipe 2-4 inches in diameter,

they can be moved easily to new locations along the main.

The system required to irrigate the field in the predetermined time may consist of one or more laterals. Laterals

are usually not more than I3OO feet long in order to get

more efficient and uniform application of water. The ends

of the portable pipes comprising the main and laterals are

fitted with quick coupling devices to facilitate connecting

and disconnecting. (Figiire 12.3) Operating pressures

usually vary from 20-50 pounds per square inch, depending on

such factors as pipe sizes used, pump capacity, topography,

etc.

B -

FIGURE 12.3 SEVERAL TYPES OF OF QUICK-ASSEMBLING PIPE JOINTS

Lightweight, portable pipe sections vary in size from 2-6

inches in diameter and from 8-3O feet in length. Sprinkler

risers are of 3A i^ch to 1-1/4 inch pipe attached to a

portable section. They are variable in length, depending on

the height of crop to be irrigated. (See Figure 12.i*-, page

12-13.)

Sprinkler heads are spaced as determined by the operating

pressure and type of nozzles used. Forty feet between

sprinklers is a common spacing, although they may be placed

as close as 20 feet when irrigating certain crops such as
12-13

By courtesy of Atlas Supply Division-Jones a Lougtilin Supply Co.

FIGURE 12.4 SPRINKLER RISER AND HEAD

orchards. Discharge rates vary with the pressure and size

sprinkler used. A 1-inch sprinker with l/h inch x 7/32

inch nozzles operating at kO pounds per square inch pressure

will sprinkle 19.9 gallons per minute. If these sprinklers

are spaced UO feet on the line with lines 80 feet apart an

amount of precipitation equivalent to 0.6 Inches of rain per

hour will "be produced in the 60-minute period.

(2) High pressure, 5O-IOO pounds per square inch

High pressure sprinkler systems are similar to the medium

pressure systems described in (1) above. Greater discharge

rates are obtained by the use of larger nozzles operating

under high pressure, usually aro\ind 100 pounds per square

inch. While the mediiun pressure sprinkler system operating

at 50 pounds press\ire may discharge as much as 7O gallons

per minute, the high pressure head operating at 100 pounds

pressure may discharge as much as 56O g.p.m. These simple

data bring out seme of the advantages and disadvantages of

the latter type system. Principal advantages are: reduced

labor requirements due to wider spacings of pipes, less pipe

required for distribution system, and large area covered by

one sprinkler head. Principal disadvantages are: higher

pumping costs due to increased pressures, larger pipe required.
12-14

considerable crop damage results from Jet produced at

beginning and ending of sprinkler operating period (after

operating pressure is reached^ fine spray is produced which

does no damage)^ and losses due to winds which are high

because of fine spray produced.

FIGURE 12.5 HIGH PRESSURE SPRAY NOZZLE

12.50 COSTS OF IRRIGATION SYSTMS

Cost of applying water artifically vary considerably depending on

such factors as system used, land preparation needed, and size of

acreage to be irrigated. In flooding types of irrigation the major

cost is usually in the land preparation or leveling operations

needed. This cost may vary from $25 per acre to as high as $100,

with an average cost of about $38 per acre. The distribution system

itself, which may consist of easily constructed shallow ditches (on

heavy soils), is relatively inexpensive on a per acre basis. Sprinkler type systems on the other hand involve little or no land preparation costs, but do have a relatively high per acre cost for the

distribution system. The following table shows the average cost for
12-15

irrigation equipment based on a study made on 58 farms in Michigan

in 19k6.

AVERAGE COST OF SPRINKLER IRRIGATION EQUIPMENT

Range of Acreage Average Ayerage Cost

Per Farm Under Soil No. Farms Acreage of Equipment

Irrigation Texture Reporting Per Farm Per Acre

55-125

25- 5^

2.5- 2k

5-125

Light

Muck

13

16

21

8

80

38

12

36

$ 63

88

176

50
13-1

PAET 13

STREAMBAKK EROSION CONTROL

13.10 GENERAL

13.11 Purpose and Scope

The puirpose of streambank erosion control is to control bank cutting in order to protect valuable adjoining farm land and reduce

the silt load of the stream. This control will be mainly through

the use of vegetation supplemented by whatever mechanical

installations are necessary to insure the satisfactory establishment of the vegetation.

Streambank protection work is one of the best methods of improving wildlife conditions^ because it usually provides food, cover,

and water close together and improves the stream for fish.

Streambank work done on any segment of a stream will be affected

by the condition of the stream above and below the segment being

considered. Therefore, it is desirable to protect the entire

length of tne stream at the same time. Frequently it will not

be possible to protect the entire stream at one time, but a plan

for the entire stream can be made so that work done on any segment will later fit into the entire Job.

13.20 INVESTIGATIONS

13.21 Physical Features

The behavior of streams at flood stage or near flood stage is

often unpredictable without detailed study. This makes it advisable to avoid jobs of large size unless good engineering assistance is available.

Before treatment of any streambank is started, several things

should be considered:

Size of watershed draining into the stream.

Expected runoff and flood peaks.

Expected ice and debris load carried by the stream.

Causes of existing meandering and erosion. Included among

them may be:

Fallen trees deflecting the water from its normal direction of flow.

Trees or brush growing on the inside of a curve deflecting water against the cutting bank.
13-2

Water from a waterway or smaller stream entering the

channel and depositing sediment^ thus deflecting the

water against the cutting "bank.

13.22 Legal and Economic Aspects

The flow line of a stream is often the property boundary between

adjacent farms. Care must be taken not to divert a stream from

its natural channel; the ultimate result may be to trespass on

another man*s property.

The economic soundness of any project should be determined at

the very outset. The cost and damages of the control should be

weighed against the resulting benefits.

13.30 TEEATMENT

13.31 Vegetation

Most of the streambank protection with which the farm planner

should be concerned can be accomplished by the establishment of

a suitable type of vegetation (grass, shrubs, or trees). In

order to satisfactorily establish vegetation, it may be necessary

to protect the vegetation during establishment by mechanical

means such as stakes, mats, pile, or rock Jetties according to

the conditions present.

13.32 General Treatment Recommended

a. Protect the stream from livestock. If stock water is needed,

provide watering places where cattle will not have to cross a

steep bank. Often it is desirable to provide more than one

watering place so they can be used alternately to prevent the

stock from denuding them of vegetation.

b. Correct the causes of meandering by removing fallen trees,

removing trees or brush on inside curves, or by eliminating the

sediment carried by waterways and smaller streams through conservation practices on the watersheds or desilting dams in their

channels.

13.33 Mechanical Control May Be Needed

Control for small stream (up to six feet wide) with low banks

(three to fo\ir feet high) and small watersheds (one to two

square miles), protection from grazing is frequently all that is

needed. If after one or two years of protection from grazing,

there still are raw eroding curves, they may be treated as

indicated under Paragraph 13.3^.

13.3^ Jetted Willow Poles For Stream Protection

Control for mediimi-size streams (six to twelve feet wide) with

banks not more than eight to ten feet high, and with watersheds
13-3

of tnree to ten square miles, protection from grazing may be all

the treatment needed. However, for most streams of this size,

the following treatment is suggested:

Drive or jet in willow poles on the cutting side only at

or Just above the normal waterline in a double row with

the poles two to foiir feet apart and staggered between

rows (Figure 13.1^ page 13-^). The poles should be six

to nine feet long, three to five inches in diameter, and

should be cut from willows if available. About twothirds of the pole should be below the ground line.

Supplement with plantings of willow cuttings or plants.

Some sharp curves or higher banks may need supplementary brush

and rock wing dams or willow matting treatment described below.

13.35 Rock and Willow or Piling Jetties

Control for larger streams (more than twelve feet wide) with

higher banks (over ten feet high) and with watersheds of more

than ten square miles, or in situations where the safety of highvalue improvements such as farm buildings or highways are

involved, or where ice and debris hazards are high, the following

treatment is suggested:

a. Construction of a Willow Rock Deflecting Jetty (Figure 13.2,

page 13-5)

Step 1. Tying willows into bundles. Willows composing a

bundle should be as nearly uniform in length as

possible. Tie at two places with No. 9 black

annealed wire (long bundles should be tied in three

places.) If each bundle is tied at the same relative positions the subsequent operation of tying

the bundles together to form an integral mat will

be facilitated. Willows can be tied into tight

bundles quickly by using a device similar to the

one described as follows:

Two or three sawhorses spaced six to ten feet

apart are tied together with longitudinal

stringers. Fastened to the top of each sawhorse is a 2" X 6" which has been shaped to

leave a curved surface (concave upward) on

which the willows are laid for bundling. When

enough willows to make a twelve- to eighteeninch diameter biindle have been placed on the

rack they are tied tightly together with No. 9

wire while the willows are being compressed by

means of a double lever device consisting of

two 1" X 2" hardwood sticks connected at one

end of each with a short piece of suitable rope

or cable. (One stick is passed under and

around the bundle, then crossed with the other
13-^

r^A

Equipment '• Centrifugal or ofher auifoble pump, ISO G.P.M., ^

(¡O'heocf), 2"discharge, 4-5'discharge hose, 15

inlef hose and e>'of I'A'pipe for a Jef.

Method :

Prepare a hole tvifh jet pipe and hose by working

the jet up and down fo o depth of lO'fo 121 LeOk

jet in for half minute or so to be sure enough

9ond has been displaced fo allow easy plocinq of

pole, fíffer the pole has been placed if should be

secured by shoving the jet in a few times at an

angle near the fop of the hole. Use two rows of

poles on long curves and four or five rows in

sharp bends. Sand bar willofv cuttings should be

planted fo form a living revetment. Protect

ogoinsf livestock untHI tvHlows or other applicable

species are esfobiished.

application •

This mefhod is used in the smaller streams where

there is no heavy ice or debris load and where

the sfreem bed is sand or fine gravelPerformance •

In o typical Job^ ßOO feet long, 15 man days were

used to cut and Jet poles and tie the brace

wires ; jef pump was operated o total of S hours.

Clear and grub heavy brush or rvillow growth

from this site which may be deflecting the

stream against the eroding bank opposite .
13-5

Active bonk erosioa,;^^

Woter Surfoce

/

SECTION A-A

Rock

4llf^

Willow bundles^

SECTION B-B

TRANSITION SECTION

SECTION C-C

-!gw,.. j\w;">..'.^i;.vk^^ - -,, Rock

Willow bund

SECTION D-D

TYPICAL PLAN S SECTIONS

ROCK a WILLOW DEFLECTING JETTY

REGIONAL OFFICE

U. S. DEPARTMENT OF AGRICULTURE

SOL CONSERVATION SERVICE

HH. BENNETT. CHIEF

Reference- Token from Winter Work

Construction Methods

by OR Zeosmon a N.E.Minsholl

Oroftiftg Approvo »provol

¡TKACeO CHCCKEOl O*T4 , ,»--

R.N. I S M G. F WS. '10-31 -38!'-'-^"^

FIGURE 13.2 ROCK AND WILLOW DEFLECTING JETTY
13-6

sticky and when pressiire is applied to the ends

of the sticks^ the rope on the upper side and

the crossed sticks on the sides and top serve

to compress the bundle.)

Step 2. Preparing the site. At the location selected for

the deflecting Jetty, the bank should be sloped for

a "transition section" at least 1:1 for a distance

of ten to fifteen feet upstream from the point where

the Jetty will swing away from the bank into the

stream.

Step 3. Constructing the Jetty. Beginning at the upper end

of the transition section, lay the willow bundles

closely together with the butt end up working the

tips into the stream bed. Tie each bundle to the

adjacent bundle to form an integral mat. (Occasionally it will be necessary to place a bundle or two

with the butt ends down to avoid a "fan" effect.)

The portion of the Jetty extending into the stream

must be higher on the bank side as indicated in

Section C-C, Figure 13.2. In order to obtain this

condition, place a wedge-shaped pile of rock in the

stream bed with the higher portion of the wedge

underneath the butt ends of the initial willow mat

layer. The top of the mat is then covered with

rock, with the heaviest rock placed near the butt

ends to resist displacement by high water velocities. Successive layers of willow mat and rock are

added until the desired height is obtained. Be

sure to work the tips of the willows into the

stream bed. When unusually high velocities are

encountered, it is advisable to place a layer of

hog wire on the bed on the stream under the initial

rock and willow layer, bringing the wire around the

tip of the Jetty, up and over the top of the mat

and fastened to it.

b. Constructing the piling deflecting Jetty (Fig\ire 13.3, page

13-7) . T^e upper end of this Jetty is constructed the same as

the rock and willow deflecting Jetty. Piling is then driven or

Jettied as indicated in Figure 13.3.

13.36 General Points Applicable to Both the Jetties

a. Slope of the Jetty

The mat should be bank high at the Junction with the bank. The

Jetty should slope toward the downstream end to produce the

desired effect of deflecting the stream away from the eroding

bank and depositing silt behind the Jetty.
13-7

Slop« Appra» I I

PERSPECTIVE SKETCH

Brush mot to protect bonk at

junction of piles and bonk.

NOTE - -

Spsct pi4«< I'-e" min. out opprox

6'-0" from bonk, then 3-0" min. the

bolonc« of the woy out in the stream

Pííir 'fo'^be driven to 4 to 4 of

their toto» length. ^i***

PLAN a PERSPECTIVE

OF PILING DEFLECTING JETTY

REGION 5 REGIONAL OFFICE

U S. OEFÄfttMENT OF AGftlCÜLTÜME

SOIL CONSERVATION SERVICE

H. H BENNETT, CHIEF

Reference- Token from Winter Work

Construction Methods

by O.R.Zeosmon bnd NE.Minsholl

WAFTING APPROVÄtr iTI

Traced !Ch«cK«d

HHICAL APPROVAL

rown

IC.R.N. i ^,M.(j,

'JÍÁ. Ui Ja.

,L-3259

FIGURE 13.3 PILING DEFLECTING JETTY

259293 O - 53 - 20
13-8

b. Angle of Jetty With Bank

In general, the Jetty should not be built at right angles to the

bank. A good rule to follov is to place the jetty at the angle

which will give the maximum deflection of the current without

setting up damaging eddies at either end of the protective work.

Consideration must be given to the amount of restriction of the

channel that can be allowed taking into accoimt the proximity

of the opposite bank and the prospects of scouring a new channel

without placing too high a head of water against the structure.

If the opposite side of the stream consists of a high bank which

cannot function as a flood plain, there is little chance of the

protective work being successful. In other words, do not attempt

streambank protection between opposite high banks where velocities cannot be reduced by the spreading of the flood waters.

c. Spacing of Jetties

A general rule for spacing is difficult to formulate due to the

variation in conditions encountered, such as degree of curvature of eroding bank, changes in velocity and quantity of discharge, soil types, width of stream, property to be protected,

etc. Judgment in "sizing up" each particular installation must

be exercised. The observation made on the flow of water past a

completed upper Jetty will help locate the next structure

below, taking into account, of course, the effect that various

stages of flow may have on the behavior of the current. One

"rule-of-thumb" method for spacing is illustrated in Figure

13A.

FIGURE 13.4 METHOD OF LOCATING JETTIES

Point "A," location of first Jetty, is the intersection of the

centerline of flow and the eroding bank. Jetty "C" is located

by drawing ÏÏB parallel to the flow line and across the toe of

Jetty "A." AC is twice AB. Jetty "D" is located by projecting

a line across the toe of Jetties "A" and "C." The remaining

Jetties are located the same as "D." Supplementary Jetty "K"

located AC distance upstream from "A" should be approximately

one-half regular size.
13-9

Generally, vhen curvature of the eroding bank exceeds 30 degrees

(190-foot radius), it is safer and more economical to use some

type of revetment for protection instead of Jetties.

d. Vegetative Treatment

Deposition of silt should occur in the area immediately adjacent

to and below the Jetty. The area between Jetties should be

planted with bush willow cuttings and other desirable species and

protected from grazing. On all types of streambank Jobs, plant

moisture-tolerant shrubs. Other suitable plantings can be made

between the bank and the fence. If enough area is available,

timber species of some value like cottonwood and black walnut

should be planted.

e. Maintenance of Streambank Work

All types of streambank control involving the use of willows will

ir'equire maintenance. Better protection will be obtained if the

willows are cut periodically to keep the stems small and pliant

so they will bend over and "shingle" the streambank during periods

of high water. Willows and other trees planted for bank protection should always be cut out before they reach two inches in

diameter. Debris lodged against banks during floods should be

removed immediately afterwards. Brush growing on inside curves

should be cut down periodically.

13.37 Jacks for Streambank Control

A third method of streambank control which can be used rather

easily by farmers consists of placing one or more rows of Jacks

along the streambank. They can be used on any of the streams

previously mentioned.

a. Construction of "Jack"

1. These are constructed by cutting three poles 10 to I6 feet

in length, depending on the depth of stream which is to be

controlled. (Multiply depth of stream by l.k to deteimine

length of poles required.)

2. These are crossed and wire together at the midpoints.

The ends are then tied together with No. 9 wire, as shown in

Figure 13.5^ page 13-11.

3. The next step is to place the "jack" in the stream. A

series consisting of enough to protect the area where cutting

occurs should be constructed. They should be spaced as close

together as possible, with not over one Jack space apart.

This will provide an almost continuous line of revetment.

(See Figure 13.6, page 13-12.)
13-10

k. They are held in place by tying the center of the Jack

with cable clamps to a main cable which is carried around

through the center of the jacks on the area to be protected.

The upper end of this cable is tied to a dead man, which in

turn anchors all the "jack" as a unit. The cable should be

1/2" to 3/^"^ depending on length and depth of stream. The

dead man should consist of about a 6' timber about 8" to 10"

in diameter. Each jack should be weighted by rock which can

be wired onto the poles.

5. If permanence is desired and vegetation will not furnish

the ultimate control, angle irons or reinforced concrete

posts can be substituted for the poles in the "jacks" as

mentioned above. Also some steel fabrication plants make

them for sale on a contract basis.

13.38 Stream Straightening

Straightening of stream channels for control of streambank erosion should rarely be undertaken as it is very expensive and may

result in further bank cutting due to the increase in grade of

the shortened channel. Where straightening may seem advisable

the assistance of an engineer should be secured before recommendations are made.
13-11

''^JACK^

^9 l/V//?^

/=D/^ Çr/e£'AM^ ú/r///G// t/£¿oc/7-y A /^CP^^

DETAILS OF JACK

U. s. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT, CHIEF

REFERENCE:

CARTOGRAPHIC APPROVAL: TECHNICAL APPROVAL:

F.S.

CHECKED:

7-31-5!

DRAWING NO.

3-L-26528

FIGURE 13.5 DETAIL OF "JACK"
13-12

'Vp^ _.F^

!T ——-^Si

U-—-'^

METHOD OF PLACING 'JACKS'

ALONG A STREAMBANK

U. S. DEPARTMENT OF AGRICULTURE

SOIL CONSERVATION SERVICE

H. H. BENNETT, CHIEF

REFERENCe:

CARTOGRAPHIC APPROVAL:

COMPILED:

F. S.

TECHNICAL A^ROVAL:

7-31-51

DRAWING NO.

3-L-26527

FIGURE 13.6 STREAMBANK CONTROL WITH "JACKS"