(

L, Quality of Water, 4 

M, Methods of Hydrographic 

Investigation, 3

DEPARTMENT OF THE INTEKIOK

UNITED STATES GEOLOGICAL SURVEY

CHARLES D. WALCOTT, DIRECTOR

OBSERVATIONS ON THE FLOW OF RIVERS

IN THE

VICINITY OF KEV YORK CITY

BY

IIKISTT^Y ALBERT

WASHINGTON

GOVERNMENT PRINTING OFFICE 

1903
PUBLICATIONS OF UNITED STATES GEOLOGICAL SURVEY.

The publications of the United States Geological Survey consist of (1) Annual Reports; (2) 

Monographs; (3) Professional Papers; (4) Bulletins; (5) Mineral Resources; (6) Water-Supply 

and Irrigation Papers; (7) Topography Atlas of the United States, folios and separate sheets 

thereof; (8) Geologic Atlas of United States, folios thereof. The classes numbered 2, 7, and 8 

are sold at cost of publication; the others are distributed free. A circular giving complete lists 

may be had on application.

The Bulletins, Professional Papers, and Water-Supply Papers treat of a variety of subjects, 

and the total number issued is large. They have therefore been classified into the following 

series: A, Economic geology; B, Descriptive geology; C, Systematic geology and paleontology; 

D, Petrography and mineralogy; E, Chemistry and physics; F, Geography; G, Miscellaneous, 

H, Forestry; I, Irrigation; J, Water storage; K, Pumping water; L, Quality of water; M, Methods 

of hydrographic investigation; N, Water power; O, Underground waters; P, Hydrographic 

progress reports. Complete lists of papers relating to water supply and allied subjects follow. 

(B=Bulletin, PP=Professional Paper, WS=Water-Supply Paper.)

SERIES I IBBIGATIOK

WS 2. Irrigation near Phoenix, Ariz., by A. P. Davis. 1897. 98 pp., 31 pis. and maps.

WS 5. Irrigation practice on the Great Plains, by E. B. Cowgill. 1897. 39 pp., 11 pis.

WS 9. Irrigation near Greeley, Colo., by David Boyd. 1897. 90 pp., 21 pis.

WS 10. Irrigation in Mesilla Valley, New Mexico, by F. C. Barker. 1898. 51 pp., 11 pis.

WS 13. Irrigation systems in Texas, by W. F. Hutson. 1898. 68 pp., 10 pis.

WS 17. Irrigation near Bakersfield, Cal., by C. E. Grunsky. 1898. 96 pp., 16 pis.

WS 18. Irrigation near Fresno, Cal., by C. E. Grunsky. 1898. 94 pp., 14 pis.

WS 19. Irrigation near Merced, Cal., by C. E. Grunsky. 1899. 59 pp., 11 pis.

WS 23. Water-right problems of Bighorn Mountains, by Elwood Mead. 1899. 62 pp., 7 pis.

WS S3. Water resources of Porto Rif o, by H. M. Wilson. 1899. 48 pp., 17 pis. and maps.

WS 43. Conveyance of water in irrigation canals, flumes, and pipes, by Samuel Fortier. 1901.

86 pp., 15 pis. 

WS 70. Geology and water resources of the Patrick and Goshen Hole quadrangles, Wyoming,

by G. I. Adams. 1902. 50 pp., 11 pis.

WS 71. Irrigation systems of Texas, by T. U. Taylor. 1902. 137 pp., 9 pis. 

WS 74. Water resources of the State of Colorado, by A. L. Fellows. 1902. 151 pp., 14 pis.

The following papers also relate especially to irrigation: Irrigation in India, by H. M. Wilson, 

in Twelfth Annual, Part II; two papers on irrigation engineering, by H. M. Wilson, in Thirteenth Annual, Part III.

SERIES J WATER STORAGE.

WS 33. Storage of water on Gila River, Arizona, by J. B. Lippincott. 1900. 98 pp., 33 pis. 

WS 40. The Austin dam, by Thomas U. Taylor. 1900. 51 pp., 16 pis.

WS 45. Water storage on Cache Creek, California, by A. E. Chandler. 1901. 48 pp., 10 pis. 

WS 46. Physical characteristics of Kern River, California, by F. H. Olmsted, and Reconnaissance

of Yuba Kiver, California, by Marsden Manson. 1901. 57 pp., 8 pis.

WS 58. Storage of water on Kings River, California, by John B. Lippincott. 1902. 100 pp., 32 pis. 

WSCS. Water storage in Truckei Basin, California-Nevada, by L.H. Taylor. 1902. 90pp., 8 pis. 

WS 73, Water storage on Salt River, Arizona, by A. P. Davis. 1902. 54pp., 25 pis.

The following paper also should bo noted under this heading: Reservoirs for irrigation, by 

J. D. Schuyler, in Eighteenth Annual, Part IV.

SEBIES K -PUMPING WATER.

WS 1. Pumping wafer for irrigation, by Herbert M. Wilson. 1896. 57 pp., 9 pis.

WS 8. Windmills for irrigation, by E. C. Murphy. 1897. 49 pp.. =: pis.

WS 14. New tests of certain pumps and water lifts used in irrigation, by Ozni P. Hood. 1898.

91 pp., 1 pi.

WS 20. Experiments with windmills, by T. O. Perry. 1899. 97 pp., 12 pis. 

WS 29. Wells and windmills in Nebraska, by E. H. Barbour. 1899. 85 pp., 27 pis. 

WS 41. The windmill; its efficiency and economic use, Part I, by E. C. Murphy. 1901. 72 pp.

14 pis. 

WS 42. The windmill, Part II (continuation of No. 41). 1901. 73-147 pp., 15-16 pis.

(Continued on third page of cover.) 

1KB 76 2
'" &' 

Water-Supply and Irrigation Paper No. 76

fL, Quality of Water, 4 

Series j M, Methods of Hydrographic

DEPARTMENT OF THE INTERIOR

UNITED STATES GEOLOGICAL

CHARLES D. WAJJCOTT, DIEECTOE

OBSERVATIONS ON THE FLOW OF RIVERS

VICINITY OF NEW YORK CITY

HE1STRY ALBERT

WASHINGTON

GOVERNMENT PRINTING OFFICE 

1903
CONTENTS.

Page.

Letter of transmittaL ___________________________________________________ 7

Introduction----------------.---..--. _..'. .............................. 9

Methods of measuring velocity in river channels.--..---..-.--.-.---.-.-.. 14

Floats.-.I**-.--.,-.-. .--. ..-...................._.........__..-... 15

General methods.-----.--__..__.______.._.....-.................. 15

Surface floats_______.__..._____.._. ._........... . .-.-.....I...... 15

Subsurface or double floats..---......-.-...-.-...-----.--------.. 16

Rod or tube floats.... -...----_._..._-...--_.....__....__--..--,.. 17

Weirs_______________________________________________________________ 18

Current meters _-__----__-.-__-_________._________.________---__._-.- 19

Vertical velocity curves on streams without ice cover - ___-__-__---___--.-_ 20

River stations at which curves were obtained. ........ .^.............. 72

Catskill Creek at South Cairo, N. Y .___...____..___............ 27

EsopusCreek at Kingston, N. Y.... -..-..---..-.-..-....- ....._ 28

Wallkill River at New Paltz, N. Y......._... ....-..-.---...--... 28

Rondout Creek at Rosendale, N. Y_ -..-.-...----..--.---..-..--..- 28

Fishkill Creek at Qlenham, N. Y..........._..... ._...-...... 28

Tenmile River below Dover Plains, N. Y.------------------------ 29

Housa tonic River at G-aylordsville, Conn ___--___...--_-....----.. 29

Discussion of tables. ----_----_---______-_____---.-__-.._. .---._...-. 29

Flow of rivers under ice, smooth and unbroken cover. ____--___.-_-__-_-.- 48

Flow of rivers under ice, broken and tilted cover. _.____ __--_-_--____.-___ 64

Quality of river water. ___--__-____-__..-___._.-____-_..._----__________. 67

Turbidity and color.____,___..__^_._______.______.___.-,-__-----__--_ 67

Turbidity ..._._-....-.._.._.............._-...-.---.....-....._. 68

Proposed turbidity standard -_.___--_-_.---__-_------------.. 69

Method of application of platinum-wire process.--_......-.-.. 69

Method of making observations __,______-.______-. -.....-... 71

Color.-...---.:.. _.....--.---............_.-----..--............. 73

Color standards.____-___-_--.-___--.-_____._______--_-------- 74

Filling the tubes. __._____________._____---_________--____--_ 75

Holding the tubes. _----.-------...----.---------.-_---------- 75

Background .....^........................................... 75

Turbid water._______.-____-________.__--____----__-----.-_._ 75

Highly colored waters --..........-....-.-....--.-..---.--..- 75

Cleaning the tubes ............... ....^...................... 76

Alkalinity ........................................................... 76

Permanent hardness ................................................. 76

Gage heights and discharge measurements. _-_.___..---...--..-_-.---.---- 86

Index ..._..... .. . . ........_....... ............^-.............. 105

3
ILLUSTRATIONS.

PLATE I. ..4, Current meter in use suspended from a bridge; B, Cable and

car used to measure discharge of river ____--_-___-----_-_----_ 18

II. Price electric current meters ___-__--------------_.-----_-------- 20

III. Gaging station on Catskill Creek at South Cairo, N. Y.__________ 26

IV. Gaging station on Esopus Creek at Kingston, N. Y_.--______.__. 26

V. Gaging station on Wallkill River at New Paltz, N. Y ___________ 26

VI. Gaging station on Rondout Creek at Rosendale, N. Y____._____. 28

VII. Gaging station on Housatonic River at Gaylordsville, Conn . _. _. 28

VIII. A, Cross section, Wallkill River at New Paltz, showing curves of 

equal velocity, as determined by current-meter measurements; 

j5, Horizontal velocity curves on Wallkill River at New Paltz, 

constructed from data obtained on the same date as that plotted 

in A .............................. __________._.._.._...._.__ 30

I.. Diagram showing results of turbidity observations. ______________ 70

X. Tubes and disks for measuring in the field the color of river water _ 72

XI. Diagram showing results of color observations _-_--__--_-..-_--_ 74

XII. Diagram showing results of alkalinity observations--.-._____---- 76

XIII. Diagram showing results of hardness observations -.____._-.._._ 78 

FIG. 1. Cross-section curve on Esopus Creek at Kingston, showing curves 

of equal velocity as determined by current-meter measurements, 

there being no ice cover ____._____..___----------------_-_-----. 22

2. Mean vertical velocity curves for Esopus, Rondout, Catskill, and

Fishkill creeks, and Wallkill, Tenniile, and Housatonic rivers- _ _ _ _ 24

3. Comparison of the general mean velocity curve with the mean curve

for smooth bed and the mean curve for rough bed. ....___.______ 25

4. Cross section of Wallkill River at New Paltz showing ice cover and

curves of equal velocity in river channel _----------_--__________ 48

5. Mean vertical velocity curves on Wallkill River, with ice cover,

showing the effect upon the curve of variation in depth of water _ _ 60

6. Mean vertical velocity curves on Esopus and Rondout creeks and 

Wallkill River, under ice cover, showing the comparatively-slight 

variation in vertical velocity curves of rivers of this character _ _ _ 61

7. Comparison of curves for various depths of water under ice cover

with the mean of all curves taken under ice. _.....___-_.__.____ 62

8. New folding turbidity stick. _..______._......_..._..__-.-_-_______ 86

5
LETTER OF TRANSMITTAL.

DEPARTMENT OF THE INTERIOR, 

UNITED STATES GEOLOGICAL, SURVEY, . DIVISION OF HYDROGRAPHY, 

Washington, D. £., June 23, 1902.

SIR: I transmit herewith manuscript for Water-Supply and Irrigation Paper No. 76, by H. A. Pressey, entitled Observations on the Flow 

of Rivers in the Vicinity of New York City.

Respectfully, ' F. H. NEWELL,

Hydrographer. 

Hon. CHARLES D. WALCOTT,

Director United States Geological Survey.

7
OBSERVATIONS ON THE FLOW OF RIVERS IN THE VICINITY 

OF NEW YORK CITY.

By H. A. PKESSEY.

INTRODUCTION.

One of the chief resources of the United States is its water supply. 

The prominent industrial position of several States is due largely to 

the abundance of their available water. It has recently been stated 

that "the preeminent position of the State of New York is due almost 

entirely to her great natural resources;" that "her inland rivers, with 

their great water powers, have been in the past and will continue to 

be in.the future a perpetual source of wealth," and that "the history 

of the State's progress during the nineteenth century is largely a 

history of the development of her water resources." These remarks 

apply quite as aptly to some of the New England States, as they 

could not have held the front rank in the industrial world for so many 

years were it not for the very extensive utilization of the magnificent 

waterfalls of that region. In the Southern Atlantic States the great 

developments during the last few years are due largely to the development and utilization of water powers.

There is not a State along the Atlantic coast, except Delaware, that 

does not contain water powers, developed and undeveloped, and, contrary to the opinion of many, there never was a decade in the history 

of our country when the development of water power made such 

strides as during the last ten years. According to the returns of the 

T welf th United States Census the increase in the utilization of water 

power in the United States in the ten years from 1890 to 1900 was 

about 30 per cent, or 472,361 horsepower. In some States this increase 

was remarkable, as, for instance, in Maine, where in the last decade 

the developed power increased 60 per cent.

The importance of our water powers as a source of wealth can hardly 

be overestimated. This power is not confined, however, to the Eastern States, for in the great Central Northwest, on the Pacific slope, 

and elsewhere there are water powers of great size and value, many 

of which form the basis of the industrial life of large communities. 

In the broad, flat plains of the United States west of the Mississippi
10 FLOW OF EIVEES NEAR NEW YOEK CITY. [NO.76.

the rivers are valuable from another standpoint. In this region the 

streams commonly lack the fall required for power development, but 

here the water supply is, perhaps, more vital to the life of the region 

than in the coastal States. Great areas of land depend for water 

largely upon the rivers in their vicinity and upon artificial means for 

raising and distributing it over their soils. Without water there can 

be no life in this region; with water, vast areas can be reclaimed as 

agricultural land of great fertility.

In most parts of the country the public water supply of the cities 

and towns must be derived from the rivers. Large sums are expended 

every year in conducting water from the streams to the centers of 

population. Before this money is expended it is of the greatest 

importance to know that there is sufficient water at all times for the 

use of the town. Too often have great hydraulic works been built 

before proper investigation has been made of the flow of a stream, 

and great financial loss has resulted.

It is to furnish information upon which to base estimates of available water supply that the Hydrographic Division of the United 

States Geological Survey has been, during the last fourteen years, collecting data in regard to the flow of rivers in the United States, and 

their variation from season to season and throughout a series of years. 

The necessity for such data is frequently brought to the attention of the 

engineer, sometimes in a most startling manner. The lack of this 

information frequently leads to the.most disastrous mistakes in the 

construction of hydraulic works. One of the best examples of this 

in the design of a hydraulic plant was the construction of a dam and 

water-power plant at Austin, Tex. After an expenditure of $1,600,000 

it was found that a grave mistake had been made in the estimate of 

the low-water flow. The works were constructed by the city in accordance with a vote of the citizens of Austin in 1890. It was estimated 

that 14,000 horsepower could be developed, and the people felt that 

their city was to become a great manufacturing center. No hydrographic data had been collected, except from the hazy memory of the 

"oldest inhabitant." In the spring of 1890 a measurement of flow 

giving 1,000 cubic feet per second was taken as the minimum. This 

estimate was more than five times too great, as was shown by subsequent measurements. An error of 500 per cent had been made in 

the estimate, but this was not ascertained until the works were nearty 

completed.

Mistakes of this kind have occurred in every part of the country 

in hydraulic works. The Sweet water dam in California in a good 

example of a project carried through on insufficient data. The 

dam was built after a series of wet years and was soon after filled 

to overflowing, so that increased spillways were constructed, but 

since that time the water in the reservoir has never reached an elevation near the crest of the spillways, and during most of the time there 

has been the greatest scarcity of water.
PBESSBY] INTRODUCTION. 11

The Bear Valley dam is a more marked case, as the reservoir formed 

by the dam has been practically dry for several years, so that wells 

have been driven in the bottom of it.

The Gila Bend, Arizona, project is another example of the expenditure of a large sum $900,000 upon insufficient data, and subsequent 

abandonment of the scheme. In this project the dam was carried 

away before its completion, but had it been completed the scheme 

must have proved a financial failure.

Many diversion canal projects for irrigation have been either partial or complete failures on account of shortage of water; that is, 

developments have been made far beyond the capacity of the stream.

A great number of water-power plants have been constructed upon 

insufficient data, and later, auxiliary steam has been found necessary. Allowance was not made in the original.estimates, so that in a 

number of instances the project has been found unprofitable. Knowlof the flood flow is also of great importance in designing the dams and 

waste ways.

Frequently the cause of such errors is a complete ignorance of the 

hydrographic conditions in the drainage basin of the stream and 

often of the region in which the stream is located. In a few cases no 

adequate efforts have been made to obtain information; perhaps a 

single measurement may have been made at a time when a local resident informed the investigator that the "river is now as low as it 

ever gets." In order to test the accuracy of such methdds, the writer 

has often asked old inhabitants on the banks of the river as to the 

variation in the river height, and has been informed that "it is now 

at its lowest stage;" or, that '' it never falls more than 2 or 3 inches 

below its present height." At a later visit to the stream in the same 

season the river surface has been found to be at an elevation 2 or 3 

feet below its previous stage. The word of the oldest inhabitant is 

sometimes fairly reliable as to high water, but his information as to 

low-water stages should be carefully checked, and the fact that a 

number of the inhabitants say that the river never goes lower is not 

sufficient evidence upon which to construct hydraulic works.

Rainfall data are often used in discussing the variation of flow of 

a stream, and numerous theories and formulas are applied to show 

that the flow can never fall below a certain amount, these theories to 

be sadly shaken later, when measurements are made and the facts 

ascertained. In a few cases greater weight has been given to these 

theories than to actual measurements, even though the measurements 

were made by a careful and reliable engineer. The measurements 

were lower, perhaps, than theory would suggest, and therefore the 

measurements must be wrong.

In studying the flow of a stream every possible source of information should be utilized even the ideas of the oldest inhabitants but 

to most engineers it is very reassuring to know that actual measure-
12 FLOW OF EIVER3 NEAE NEW YOEK CITY. [NO.76.

ments of the discharge have been made and are available for use. If 

measurements of the stream under consideration have not been made, 

then results obtained from measurements of rivers in the immediate 

vicinity can be used to advantage, care being taken that the hydrographic, topographic, geologic, and forest conditions in the two basins 

are similar.

As an example of the difficulties under which a prospective investor 

labors, there are now before the writer reports upon a certain stream 

in New York State made by five different engineers, all of good 

standing, in which estimates of the minimum flow of the stream 

under consideration vary from 0.20 to 0.40 cubic foot per second per 

square mile; that is, the minimum flow given by one engineer is just 

twice that given by another. As the development of a water power is 

limited largely by the low-water flow, the uncertainties arising from 

such divergent opinions are apparent. Since these reports were 

made (1900-1901) the flow of this stream has been measured, and the 

lowest estimate made by the engineers has been shown to be at least 

100 per cent too great. In estimates of this kind facts are needed 

that is, actual measurements of discharge.

No further discussion is probably necessary to convince most 

thinking people that the measurement of the larger streams of the 

United States is an important undertaking, and that capital will be 

invested in power developments, irrigation, sanitary and other 

hydraulic works more freely when information as to the flow of the 

streams is available.

In making measurements of streams it is of course desirable that 

rapid and economical methods be used, if such are of sufficient accuracy. Methods of stream measurements have been discussed in 

Water-Supply Paper No. 56, and it is not the purpose of this paper to 

deal with that question extensively, but rather to point out certain 

facts developed, during the last few months, by measurements of 

streams in the southern part of New York State, with the idea that 

some of the data obtained from these measurements may be useful in 

studying the flow of other streams and may assist in the selection of 

methods that will expedite the work and yet give results sufficiently 

accurate for all practical purposes.

In considering the future demands of the city of New York for 

water several additional sources of supply have been suggested: Housatonic River, Teiimile River, Wallkill River, Rondout Creek, Esopus 

Creek, and Catskill Creek, the Hudson River or some of its upper 

tributaries, Lake George, Lake Champlain, and the Great Lakes. 

The three last-named sources have been discussed in print somewhat 

extensively a and will not be taken up here. It has been found* that 

the supply from Lake George would not be adequate; that Lake

« Report of Merchants1 Association of New York on the water supply of the city of New York, 

August, 1900.
PBBSSBY.] INTKODtJCTION. 13

Champlain is at too low an elevation for economical use, and that the 

supply from the Great Lakes would entail great and unnecessary 

expense. The water from the Hudson River might be taken near its 

headwaters and conducted to New York City by a long aqueduct, or 

the intake might be located just above Poughkeepsie, in which case 

the water would have to be pumped from the river and filtered before 

delivery to the city. In either case it is important to know the discharge of the Hudson at various seasons of the year to determine the 

quantity available and also the effect of the diversion of water upon 

the regimen of the river.

The United States Geological Survey has for several years been 

measuring the daily flow of streams throughout the United States, 

the results of these measurements being used for different purposes, 

including irrigation, water-power, and sanitary constructions.

Measurements of flow of Schroon River at Warrensburg and of the 

Hudson at Fort Edward and Mechanicville have been made, also of 

the Mohawk and its chief tributaries at various points, and the results 

of these have been published in the annual reports.

The measurements of the rivers discussed in this paper were started 

at the suggestion of Mr. George N. Birdsall, chief engineer Bureau of 

Water Supply, New York City, in order that data might be available 

for investigations as to additional water supply for New York City. 

The following stations were established by the United States Geological Survey during the summer of 1901 and have been maintained 

continuously since that time.

Gaging stations on rivers near New York City.

Stream.

Tenmile River ........

Housatonic River ......

Catskill Creek ___..___:..

Wallkill River ........

Rondotit Creek .........

Fishkill Creek. .........

Location of gaging station.

Dover Plains, N. Y ----------

South Cairo, N. Y ___________

New Paltz, N. Y- _...........

Glenham, N. Y...._ ---------

Drainage area 

Above 

proposed 

reservoir.

Sq. miles. 

200 

1,030 

140 

243 

464 

184 

158

Above 

gaging 

station.

8q. miles. 

195 

1,020 

260 

312 

735 

365 

198

Above 

mouth.

Sq. miles. 

195 

1,580 

394 

417 

779 

«369 

304

"Above junction with Wallkill River.

A reconnaissance of each of these streams was made, and stations 

were selected at points where measurements could be most accurately 

made, and as far as practicable at points where it was thought knowledge of the flow would be most desired in the future study of these
14 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. 76.

watersheds as sources of increased supply for New York. The results 

of the observations at these stations have been published in the 

Water- Supply Papers of the Survey. The height of the water at each 

station has been noted twice each day by a local observer and currentmeter measurements have been made at frequent intervals by a hydrographer. From these meter measurements a rating curve has been 

drawn for each station which shows the relation between the height of 

the water in the river and the discharge. From this curve and the 

daily mean gage height the flow of the river for each day in the year 

since the establishment of the station can be determined. These data 

will be of the greatest importance to the engineers selecting the source 

of supply, as they furnish the first continuous record of the flow of 

these streams .and give a basis upon which to compute the supply 

available from each stream, which, with the topographic maps of the 

survey and the detailed surveys of the reservoir sites, will give complete data for the estimate of the quantity of water that can be furnished by each of these drainage basins and of the relative cost per 

million gallons of the supply from each.

In addition to the measurement of the discharge, determinations of 

turbidity, color, alkalinity, and hardness have been made upon each 

of these streams and are now being continued, and it is thought that 

these data will prove valuable in the final selection of the new source 

of supply. Results are given in the Water-Supply Papers of the 

United States Geological Survey, and are tabulated at the end of this 

paper.

In making gagings at these stations it was thought desirable to 

investigate the variations of flow in different parts of the river channel, 

in order to determine at what points the velocity could be measured 

to ascertain the mean velocity in the channel without unnecessary 

expense or loss of time. Before taking lip the measurements and the 

vertical velocity curves constructed, it may not be out of place to 

describe briefly some of the methods used for the measurement of 

streams.

METHODS OF MEASURING VELOCITY IN RIVER CHAlSrThere are in common use a number of methods of measuring the 

flow of rivers. In general these involve the determination of the mean 

velocity of the current and the area of the cross section of the stream. 

The latter is easily computed from soundings made at frequent intervals across the channel. These soundings must be taken at intervals 

so short that the bottom of the river may be considered a straight line 

between soundings. Usually the velocity of the current is determined in sections of the river channel, these sections extending 

between the points of soundings. The summation of the area of each 

of these sections gives the total area of the cross section. When the
PBESSEY.] METHODS OF MEASURING VELOCITY. 15

total flow of the river is known and is divided by the area of the 

cross section the result is called the mean velocity of the river. It is 

this mean velocity that we try to determine in any method of stream 

measurement, but, as a matter of fact, it can not be actually determined until the total flow is known.

In the determination of the mean velocity of the current there are a 

number of methods giving results more or less accurate, all of which 

should be familiar to the engineer, so that the method best suited to 

the conditions at hand may be applied.

FLOATS. 

GENERAL METHODS.

Floats are frequently employed to determine the velocity of the 

current. There are three general types in common use: First, surface floats; second, subsurface or double floats; third, tube or rod 

floats. The general method of procedure is the same whichever form 

of float is used. The site for making a float measurement should be 

on a straight reach, having a fairly uiiiform cross section. The flow of 

the water should be regular, without sudden rapids or stretches of still 

water, and should exhibit no tendencies to form eddies or cross currents caused by irregularities in the channel or resulting from the 

effect of a sharp bend above the reach. The course of the floats 

should have a length of from 100 to 300 feet, and the areas of cross 

section at the upper and lower ends of this course should be carefully 

determined by soundings. When courses more than 100 feet in length 

are selected, it is desirable that additional cross sections, at equal 

intervals from one another, should be measured. As a preliminary 

step, a base line should be laid out by tape on the bank as nearly as 

possible parallel with the stream, and points should be marked opposite the cross sections to be used. If the stream is not too wide the 

soundings in the cross sections can be taken most conveniently along 

a tagged rope stretched across the channel at right angles to the base. 

If the depth does not exceed 4 feet this can be done by wading, the 

depth being read on a rod graduated to feet and tenths. Should the 

depth of the channel or the temperature of the water make wading 

impossible, a boat may be used. On large rivers, where a tagged rope 

can not be employed, the boat from which the soundings are to be 

made should be located by simple triangulation. Soundings should 

be read to tenths of a foot and be taken preferably at equal distances 

apart. In deep rivers a tagged rope or chain with lead weight can 

be substituted for the rod.

SURFACE FLOATS.

In reconnaissance work, in which the equipment is as a rule limited 

by transportation facilities, surface floats consisting of chips will be 

found most convenient. The use of rod floats, though giving more
16 FLOW OF EIVEES NEAE NEW YOEK CITY. [NO. 76.

directly the mean velocity, has many disadvantages, and should not 

be attempted unless the time and opportunity permit of obtaining 

floats of the required lengths. In the simplest case but one man is 

needed to make the observations. The surface floats should be 

thrown into the stream a considerable distance above the first cross 

section. The hydrographer should attempt to start the floats, successively, at different distances from the shore in order to determine the 

velocity in different parts of the channel. The time of the passage 

of each float between the upper and lower cross section should be 

noted, preferably by a stop watch, and also the position of each float 

with respect to the tags on the ropes. This will enable the hydrographer to determine whether or not he succeeds in covering the 

different parts of the stream, and it will serve as an aid in the computation. The observations should be continued until all parts of 

the stream have been covered.

On wide rivers range poles may be established 011 opposite shores 

to mark the upper and lower cross sections. The location of each 

float as it crosses these imaginary lines can readily be recorded by 

triaiigulation. A light traverse plane table will be found especially 

useful in obtaining a graphic record.

The surface floats show approximately the surface velocity of the 

stream at the point of measurement. The results obtained by this 

method are subject to errors due to wind and surface currents and 

eddies. The velocity shown is that of the surface of the river, while 

that required for computation of discharge is the mean velocity of the 

cross section. Unfortunately, the relation of the surface to the mean 

velocity of the vertical is not constant, yet for streams of the same 

general character of bed, banks, velocity, etc., the ratio is sufficiently 

constant to allow the mean velocity to be computed with fair precision 

from the surface velocity observations.

SUBSURFACE OR DOUBLE FLOATS.

The double float consists of a small surface float connected by a 

fine cord to a larger subsurface float, which is so arranged that it 

shall always remain at the point of mean velocity in the current. The 

surface float may consist of a flat block of wood or a tin water-tight 

drum, which floats upon the surface of the water with sufficient buoyancy to prevent the larger subsurface float from sinking. The 

subsurface float may consist of two sheets of galvanized iron set at 

right angles, weighted at the bottom, with an air-tight cylindrical 

device at the top, in order that it may at all times keep its vertical 

position. A round, hollow cylinder of tin also makes an excellent 

subsurface float. The tension on the connecting cord should be at 

least 2 or 3 pounds, and the cord should be of silk and as fine as possible in order that its resistance to the current should not have a 

marked effect upon the velocity of the floats. The length of the cord
PBESSET.] METHODS OF MEASURING- VELOCITY. 17

should be so regulated that the lower float may be at the point of 

mean velocity, and the resistance of the upper float and the cord should 

be made as small as practicable. A small flag should be placed upon 

the upper float in order that its position may be easily determined at 

all times. The chief objection to double floats is the uncertainty as 

to whether the cord is vertical and the consequent uncertainty as to 

the position of the subsurface float. Another objection is the modifying effect of the surface float and the cord upon the velocity of the 

lower float, as in great depth the exposed surface of the cord may 

exceed that of the float. A third objection is the uncertainty as to 

the vertical position of the lower float, as, owing to changes in depth 

of water and local conditions, the point of mean velocity may change, 

whereas the length of the connecting cord must remain constant in 

each run. This may introduce a noticeable error if the increase in 

depth is large, as the retarding effect of the slow velocity near the 

bottom of the river will not be felt by the float, and the result will 

show too high a velocity. The lower float may tip slightly, owing to 

eddies or other causes, thereby changing the exposed surface, or, 

unknown to the observer, the lower float may strike a bowlder, causing its velocity to be checked. In many cases these objections would 

not be at all serious, but, in general, when floats are to be used better 

results can be obtained, when the depth is not too great, by the use 

of rod or tube floats.

ROD OR TUBE FLOATS. .

These consist of long, cylindrical tin tubes or wooden poles, 2 or 3 

v inches in diameter, weighted at the bottom, so that they will float 

vertically with only 2 or 3 inches exposed above, the water surface. 

These rods integrate the velocities in a vertical section and give 

approximately the mean velocity of the current. It is important that 

they should extend nearly to the bottom, as otherwise the velocity, as 

shown, will be too great, yet the greatest care must be taken, that 

they do not at any time scrape upon the rocks at the bottom or sides 

so as to retard their movement. Rod floats are free from many of 

the objections to double floats, as there is no uncertainty as to their 

position nor as to the point of mean velocity in the channel. They 

are not, however, suitable for very deep rivers, or for channels where 

the depth varies considerably, or where weeds grow in the bed of the 

stream. Mr. James B. Francis has stated that the rod floats travel a 

little faster than the mean velocity of the water even for the depth of 

immersion. The float will be subject to pressures proportional to the 

square of the relative velocities of the water at different points, and 

when it has attained its full speed there will be equilibrium between 

these different pressures. This equilibrium may exist, however, when 

the speed of the float is somewhat different from the mean velocity of 

the water, the latter being the arithmetical mean of all the different

IRR 76 03 2
18 FLOW OF EIVEE8 NEAR NEW YORK CITY. [NO. 76.

velocities throughout the depth of immersion. The following formula 

for correcting an observed velocity was derived by James B. Francis 

from his Lowell experiments:

Where Vm is .equal to true mean velocity in vertical, V0 equals 

observed velocity of tube, d equals mean depth along path of tube, 

d l equals depth of immersion of tube.

Col. Allan Cunningham a has, however, calculated that such floats 

move somewhat slower than the water in which they are immersed. 

The error of assuming that the velocity of the tube represents the 

mean velocity in the vertical will not be material unless tubes too 

short are used, in which case the velocity as shown by the tube should 

be somewhat reduced.

WEIRS.

By the method of weirs the discharge of the stream is computed by 

means of an empirical formula, which varies for different types of 

dams or weirs. On creeks or small rivers it is sometimes practicable 

to build a timber weir across the channel, causing the total flow of the 

stream to pass over the sharp edge of the weir crest. By observing 

the head on the weir, computations of the flow can be made. This is 

probably the most accurate method applicable to small streams. On 

large rivers, however, the cost of a weir is usually so great as to be 

prohibitive, so that if there is not a weir or dam already in the stream 

it is necessary to resort to measurements by floats or current meters.

On many of the rivers of moderate size the conditions are unfavorable for successfully applying either of these methods. For instance, 

on streams used for manufacturing purposes dams occur at frequent 

intervals, interrupting the regular flow, and in many cases holding 

back the night flow for use during the following day, so that the discharge during the night may be either nothing or a very small percentage of the day flow. Then, too, the shutting clown of the mill 

wheels for an hour at noon may have a pronounced effect upon the 

results of float or meter measurements made below the mill. Unfortunately these variations are not always apparent to the hydrographer, 

and surprise and annoyance are caused by finding that the river 

height differs by several tenths from the gage as read by the regular 

observer a short time before the hydrographer arrived at the station.

Under the conditions described, better results can undoubtedly be 

obtained if there exists upon the stream a good dam which can be used 

as a weir. It should have a level, even crest and a constant cross 

section, with sufficient pondage to reduce the velocity of approach, 

and it should be free from leakage. Masonry dams are better for

"Recent hydraulic experiments: Min. Proc. Inst. Civil Eng., Vol. LXXI 1883.
U. 8. GEOLOGICAL SURVEY WATER-SUPPLY PAPER NO. 76 PL. I

A. CURRENT METER IN USE, SUSPENDED FROM A BRIDGE.

B. CABLE AND CAR USED TO MEASURE DISCHARGE OF RIVER
PBESSEY.] METHODS OP MEASURING VELOCITY. 19

this purpose, for they are more likely to be tight and to have an even 

crest. Timber dams, although level when first constructed, are likely 

to settle at various points, thus producing an uneven crest elevation. 

There are, however, many good timber dams practically free from 

leakage and with crests sufficiently uniform for accurate work.

Having selected a dam as the proper site for a station, a careful 

survey must be made of the crest line and of the upper and lower 

slopes, so that it can be compared with other dams or with experimental sections for which the coefficients of flow are known. The 

experiments of James B. Francis, of Fteley and Stearns, and of John 

R. Freeman, George W. Rafter, and others at Cornell University, 

have given-coefficients upon many sections of various forms. It is 

probable that the dam selected for the station will not be exactly like 

any of the experimental forms, but it will resemble some of them so 

closely that coefficients can be selected for the computations.

When the mill gates are open a part of the flow is diverted from the 

river through the mill race, the gates, and the tailrace.

The amount of the diversion must of course be measured and added 

to the quantity flowing over the dam, in order to determine the total 

discharge of the stream. In many factories the quantity flowing 

through the wheels varies from day to day, and also during different 

hours of the day, so that careful records must be kept of gate openings, 

in order that proper allowance may be made for these variations. The 

size and the make of the water wheels must be ascertained, and the 

wheels be used as water meters for the determination of the flow 

through them. Many of the modern wheels have been carefully rated. 

Where such ratings have not been made, usually records of wheels of 

the same type, though possibly of different makes, can be found and 

the records be compared. Water wheels as meters give fairly accurate records of the discharge.

The Chezy formula or surface-slope method has been extensively employed in gaging large rivers. The proper coefficients to be applied 

are usually determined from the auxiliary formula of Gauguillet 

and Kutter. One difficulty in the application of this method lies in 

the selection of suitable friction factor or coefficient of roughness.

CURRENT METERS.

The current meter has been found best adapted to the general measurements made by the United States Geological Survey, and is used 

almost exclusively in its hydrographic investigations. (Pis. I and II.) 

Occasionally, however, either a meter is not available or the conditions 

are not favorable for its use. In such cases weirs or floats have been 

nsed, though a Pitot's tube, hydrometric pendulum, or hydrometrie 

' alance might in exceptional case be used to advantage.

The current meter has been described, and instructions for the care 

and use of the instrument have been given in Water-Supply Paper
20 FLOW OF RIVERS NEAR NEW YORK CITY. [NO.76.

No. 56. The object of the present discussion is to give a few additional facts as to the point at which the meter should be held to 

determine the mean velocity in a channel, as deduced from measurements recently made upon rivers in the southern part of New 

York State. The current meter may be used to determine the velocity of a river in four ways: First, by making point measurements 

at a depth corresponding to the approximate position of the thread 

of mean velocity; second, by deducing the mean velocity from observations made at other points in the same vertical; third, by the 

integration method; fourth, by point measurements made at regular 

intervals throughout cross sections of the river. In the first two of 

these methods it is important to know the relation between the velocities at various points in the section. In the first method the position 

of mean velocity must be known, and in the second method the 

relation between the surface velocity, or the velocity at mean depth, 

to the mean velocity must be known. In either of these cases the 

form of the vertical velocity curve will determine the coefficient to be 

applied to the observations.

VERTICAL VELOCITY CURVES ON STREAMS WITHOUT ICE

COVER.

Studies of the vertical velocity curve made on the Mississippi River 

by Humphreys and Abbott, on the Connecticut by T. G. Ellis, on 

the Merrimac flume by Wheeler and Lynch, on the Potoinac by C. C. 

Babb, and recent experiments by others, notably those at Cornell 

University by E. C. Murphy, indicate that the point of mean velocity 

in a given vertical section is at a depth varying from six-tenths to 

two-thirds of the total depth of the section, measured from the surface down. The values found in the experiments were as follows:

Depth from surface of point of mean velocity.

Experimenter.

Cyrus C. Babb ... . _._.___.___.._____

T. G. Ellis _ ....... ...................

E. C. Murphy .___________.... ........

Wheeler and Lynch .-.-_ ____.- ._....

Stream.

Potomac River _____ . _ . _ _ _

Connecticut Biver_ _ _ . _ .......

Cornell flume _ _....-.

Merrimac flume - . . . . . . ....

Depths.

0.58

.63

.64

«.65

.67

"For depths between 6 and 9 feet, the proportionate depth of point of mean velocity becoming 

less as the depth of the water decreased, and becoming 0.55 for depths of water between 1 and 2 

feet.

The Cornell experiments indicate that measurements made at sixtenths of the depth yield results 3.5 per cent too large, the depth of
U. S. GEOLOGICAL SURVEY WATER-SUPPLY PAPER NO. 76 PL. II

PRICE ELECTRIC CURRENT METERS.
PBBSSEY.] VERTICAL VELOCITY . OUBVES. 21

mean velocity being nearly two-thirds of the depth. The measurements at Cornell were, however, made in the canal, the cross sections 

of which have a greater ratio of depth to width than most rivers, and 

decidedly more than the Mississippi, Connecticut, and Potomac, upon 

which the above coefficients were obtained. There can be no doubt 

but that the difference in the ratio of the depth to width is a factor 

likely to affect the position of mean velocity.

The bottom and sides of the channel retard the flow close to them 

in proportion to their roughness, this retardation being due more to 

the impeding of the flow by eddies than by friction alone. The retardation of the surface velocity has been attributed to the rising, by vertical 

motion, of the lower w*ater to the surface after being checked in its flow 

by striking against the rough bottom and sides of the channel. The 

variation of the velocity in the river channel is shown in PI. VIII 

(p. 30) and fig. 1.

Mr. Frederick P. Stearns has attributed the reduction of surface 

velocity to the general retarding of the layers of water adjacent to 

the banks of the stream, this water rising to the surface and thereby 

making the edges of the channel higher than the center and causing 

a flow of the slowly moving water from the sides toward the middle, thereby decreasing the surface velocity, depressing the point 

of maximum velocity, and lowering in general the filament of mean 

velocity. This depression of the maximum velocity is known to 

become more pronounced with an increase in the roughness of the 

lining, in the steepness of the banks, and in the ratio of depth to 

width. In an extreme case of a wide, shallow stream, where the bottom merges imperceptibly into the banks, maximum velocity occurs, 

under normal conditions, at or very near the surface of the center 

of the stream. On the other hand, in a deep, narrow channel, as 

for instance, in a canal with vertical sides, the maximum velocity 

occurs a considerable distance below the surface, and, as the Cornell 

experiments indicate, this depression may amount to as much as onethird and even two-fifths of the total depth. Evidently, then, in such 

cases depression of maximum velocity must result in a lowering of 

the thread of mean velocity, and engineers, in making unit measurements for mean velocity, should bear in mind that white the observations at six-tenths depth give fair values for mean velocity in wide, 

shallow rivers this ratio should be increased to two-thirds in the case 

of canals and flumes or narrow natural channels.

The friction of flowing water against the air has a similar influence, 

and, though in general less marked, it may, in the case of a strong 

upstream wind, have a Decided influence upon the surface velocity 

and the point in the vertical of the maximum and mean velocity. On 

account of these resistances on the bed and bank of a stream, the 

maximum velocity of the river in a straight reach is found in the cen-
22 FLOW OF EIVEE8 NEAR NEW YORK CITY.

tral portion of the stream, and somewhat below the surface the 

actual position depending upon the size and condition of the river 

and the velocity of flow. The velocity increases from the surface 

downward for a short distance say, one-tenth of the depth and then 

decreases down to the bottom, where it reaches the minimum.

Various writers who have studied the form and equation of the 

curve representing the variation in velocities in a vertical section have

PIG. 1. Cross section on Esopus Creek, at Kingston, showing curves of equal velocity as 

determined by current-meter measurements, there being no ice cover.

come to different conclusions as to the form of this curve, the inclined 

straight line, the parabola with horizontal axis, the parabola with vertical axis and vertex at or below the surface, the ellipse, and the hyperbola each having its advocates. Humphreys and Abbott showed by 

their experiments on the Mississippi River that the curve did not differ materially from a parabola having its axis parallel to the surface 

and at the depth below the surface of the p'ositioii of maximum veloc-
PBBSSBY.] VERTICAL VELOCITY CURVES. 23

ity, the abscissas representing the velocities at the different depths 

and the ordinates the vertical distances of these depths from the 

point of mean maximum velocity. In the Mississippi River experiments the position of maximum velocity was on an average nearly 

one-third of the whole depth below the surface, varying with the 

direction of the wind. Bazin also found that the vertical velocity 

curve was in the form of a parabola, the curve varying with different 

channels and the position of maximum velocity. Professor von 

Wagner agreed with the above experimenters, but found that the 

curve differed from the parabola toward the bottom and near the 

surface, and that the point of maximum velocity varied from a little 

below the surface to a little over one-fourth of the full depth.

The exact mathematical form of a vertical velocity curve is not a 

vital question in the measurement of streams, but it is greatly to be 

desired that the -relation between the surface, maximum, and mean 

velocities should be known, so that if any one of these be measured 

accurate computations of the flow can be made, and so that if the 

velocity of the stream be measured at some particular point the 

mean velocity of the whole section can be calculated. It has been 

shown by a series of measurements, the results of which are given 

herein, that the typical vertical velocity curve is in general of the 

form shown in fig. 2; that the surface velocity is somewhat greater 

than the mean; that the maximum velocity is below the surface but 

above mid depth; and that the point of mean velocity is from 0.6 to 

two-thirds of the depth below the surface. The relation between the 

surface velocity and the mean velocity is, of course, important in the 

use of surface floats and current meters when the velocity is measured only near the surface, for some coefficient must always be 

applied to obtain the mean velocity in the vertical section. In this 

connection, some results obtained by Mr. J. B. Lippincott on rivers 

in southern California, in April, 1902, are of interest:

On the Sacramento River, at Jellys Ferry, observations for velocities have been 

taken at the top, middle, and bottom of each section at intervals of 20 feet. The 

channel is of bowlders and has a depth of from 3 to 5 feet in the low-water stages. 

The relation of the mean velocity to the top velocity on each section was determined, and then the mean ratio for the entire measurement. The measurements 

were arranged in 6 groups according to gage heights. In the first group the mean 

velocity was 87 per cent of the surface velo'city; in the second 88; in the third 88; 

in the fourth 89; in the fifth 87; in the sixth 87. The last group represents the 

highest water. The mean of 30 measurements gives a ratio of 88 per cent. In 

this case the coefficients are quite constant.

A determination on the Tuolunine River, at Lagrange,'also gives a coefficient of 

88 per cent. This river has a pebbly or stony bed, and the depths range from 1.12 

to 1.84 feet. The velocities range from 3 to 5 feet.

On the smaller rivers the determinations were less satisfactory, because when 

depths become as low as 1 foot, top, middle, and bottom velocities were seldom 

observed with meters, and unless we had three observations for velocity the mean
24 FLOW OF EIVEES NEAE NEW YOEK CITY. [NO. 76.

velocity was not considered sufficiently accurate to justify a comparison with, 

the surface velocity.

The relative irregularities of the beds of the smaller streams also introduced 

wider ranges in the relation of surface to mean velocities.

On the San Gabriel River the following results were obtained at different points 

on the stream: 0.83, 0.94, 0.95, 0.89, 0.90, 0.98; mean, 0.92.

1.00

70 80 90 100

Velocity in terms of mean velocifcy=100.

110 130 130

FIG. 2. Mean vertical velocity curves for Esopus, Rondont, Catskill, and Fishkill creeks, 

and Wallkill, Tenmile, and Housatonic rivers.

On the Santa Ana River the following determinations were made at Warm 

Springs: 0.96, 0.95, 0.91, 0.86. 0.90, 0.91, 0.96, 0.93; mean, 0.92.

The channels of these two streams are relatively rough, the water surface is 

usually from 10 to 20 feet in width, and the depths vary from 0.25 foot to 1 foot 

for the stage of water observed upon. It is rather singular to note that the 

determination of these coefficients in the smaller and relatively rough channels 

shows a higher value than in the larger channels. As previously remarked, how-
PRESSEY.] VEBTICAL VELOCITY CFBVES. 25

ever, the determinations for the San G-abriel and the Santa Ana are not considered 

as entirely satisfactory nor as reliable as the determination for the Sacramento. 

It is possible that the coefficients which we have determined for the smaller 

streams are too high, owing to the fact that the current meter could not be placed 

in the slowest film of water immediately adjacent to the bottom and sides of the 

channel, so that the mean velocity as shown may be slightly above the true

Bepthsin;

decimal'

parts of

total.

.10

.30

.30

.40

.50

.70

.80

.90

1.00

 Mean of'7$curve.

-Mean of *2>6 

"Mean of25$uri/es.

>,ge/?erp/co/jc/j 

smooth 

-ough b(

bed

50 60 TO 80 90 100 110 120 130

Velocity in terms of mean velocity = 100.

PIG. 3. Comparison of the general mean velocity curve with the mean curve for smooth bed

 and the mean curve for rough bed. (Note: The general mean curve includes all data obtained

in 78 vertical velocity curves; the mean curve for rough bed includes tbe data for 85 vertical

velocity curves, and the mean curve for smooth bed includes the data for 88 vertical velocity

curves. All of these curves were taken when there was no ice cover.)

mean velocity. This error would be relatively greater in small than in large 

streams, however. In the measurements of the small stream a Price acoustic 

meter has been used, which permits the center of the meter to be placed within 

3 inches of the bed of the creek.

In consideration of the above data it is believed that for ordinary streams discharging 100 cubic feet per second of water, or less, on stony beds, that 0.9 of the
26 FLOW OP BIVEBS NEAR NEW YORK CITY. lNO.76.

mean surface velocity for the section will represent the mean velocity for that 

section, said surface velocities being observed at numerous points across the 

stream.

a With the object of determining the ratio between the maximum surface velocities and the mean velocity, De Prony made some experiments in wooden troughs, and Messrs. Baldwin, Whistler, and Slosson 

in channels lined with planks. The coefficients obtained for converting the observed surface velocity into mean velocity were 0.81G by De 

Preny and from 0.810 to 0.847 by the latter observers in different 

channels. Subsequent experiments indicate that the coefficient is generally comprised within the limits of 0.8 and 0.9, depending upon the 

size of the channel and the nature of the bed. The Mississippi River 

experiments show the coefficients to exceed 0.9, but it is quite possible 

that the influence of the long connecting cord and surface float caused 

too large values to be .recorded for the velocities toward the bottom, 

and thus gave too high a value to the mean velocity, as Mr. Robert 

Gordon, in checking his experiments on the Irrawaddi with a current 

meter, obtained considerable reduction in the velocities approaching 

the bottom compared with those obtained by double floats. The 

coefficient would be greatest for large, deep rivers with smooth, uniform channels, and least for small, shallow streams with rough beds. 

Messrs. Darcy and Bazin derived from their experiments the following formula giving the relation between the maximum velocity and 

the mean velocity: __

where U is the maximum velocity in feet per second, Y the mean 

velocity, R the hydraulic radius in feet, and S the slope.

The variation in the coefficient to be applied to the surface velocity 

gives rise to a possible error large enough to preclude the use of this 

method of measurement when accurate results are desired. As a 

quick method it may often be used, and in a few cases, as, for instance, 

at the time of high floods, when it is impossible to use other means, 

the results obtained by this method may be of considerable value.

The mean of 78 velocity curves taken upon rivers in the southern 

part of New York State, described further on in this paper, shows that 

the mean velocity was 0.87 of the surface velocity in the vertical section (shown in fig. 3). This coefficient varied from 0.82 in the case of 

Catskill Creek to 0.93 on Fishkill Creek (fig. 2). It will be noted that 

these coefficients apply to the mean velocity in the vertical in which 

the float is run. If only one surface float is used, and that in the 

center of the river, or point of maximum velocity, it appears that 0.8 

is the proper coefficient to apply, though the chances of error are 

much greater than when surface floats are used at intervals across the 

channel.

"From Rivers and Canals, vol. 1, p. 38, by it, P. Vei-non-Harcourt.
U. 8. GEOLOGICAL SURVEY

GAGING STATION ON CATSKILL CREEK AT SOUTH CAIRO, N. Y.
U. S. GEOLOGICAL SURVEY

WATER-SUPPLY PAPER NO. 76 PL. IV

GAGING STATION ON ESOPUS CREEK AT KINGSTON N. Y:
U. S. GEOLOGICAL SURVEY

NO. 76 PL. V

GAGING. STATION ON WALLKILL RIVER AT NEW PALTZ, N. Y.
PRESSEY.] VERTICAL. VELOCITY CURVES. 27 

RIVER STATIONS AT WHICH CURVES WERE OBTAINED.

In June, 1901, a reconnaissance was made of Catskill, Esopus, 

and Rondout creeks, and Wallkill River west of the Hudson, and 

Fishkill Creek and Tenmile and Housatonic rivers east of the Hudson. 

Nearly the entire length of each stream was traversed, and a site for 

a gaging station selected on each. Early in July the stations were 

established, with the exception of that on Tenmile River, which was 

established in September of the same year. Persons living near at 

hand were employed as gage readers to take observations of the stage 

of the stream twice each day. Mr. A. E. Place was in charge of 

these stations until September, 1901, when Mr. W. W. Schlecht was 

placed in charge as resident hydrographer. The measurements given 

in this paper were obtained by Messrs. Place and Schlecht, and 

the tables and several of the diagrams were prepared by Mr. Schlecht. 

The object of the measurements made at these stations was to 

determine primarily the run-off from the various drainage basins 

and the availability of the streams as sources of additional supply 

of water for New York City. The results of the measurements, 

together with the heights of water in the river on each day, have 

been published in Water-Supply Paper No. 05. Incidentally it was 

thought best to make observations as to the point of mean velocity 

in each of these streams for use in future measurements on the 

same rivers, as well as for general information as to the most desirable 

method of making current-meter measurements on rivers in general. 

In making measurements of rivers of this character it has been the 

custom of the Hydrographic Division of the United States Geological 

Survey to divide the cross section into partial areas of regular 

width, say 5 or 10 feet, and to determine the velocity in each of these 

small areas by holding the meter at a point six-tenths of the total 

depth below the surface. The velocity obtained at this point was 

assumed to be the mean velocity in the small area in jvhich the ine^r 

was used. It was realized that this relation would not hold true in 

all streams, but in rivers with the general characteristics of those 

under discussion it was considered that no serious error would result 

from this assumption. The data in the following pages were collected 

in order to check the above assumption or to enable the hydrographer 

to determine by a point measurement the velocity at some other depth 

which might be considered the mean in the channel. Each of the stations established will now be briefly described. The drainage basins 

were described in detail in Water-Supply Paper No. 65.

CATSKILL CREEK AT SOUTH CAIRO, N. T.

The gaging station is located at the highway bridge in the village 

of South Cairo, a view of which is shown on PL III. The total span
28 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. 76.

of the bridge is 194.5 feet between abutments, the faces of which are 

vertical. The stream bed is of earth for 25 feet from the right abutment. At this point the bluestone rock ledge outcrops, covered with 

patches of loose shingle and shifting gravel, while the left side of the 

channel is covered with small gravel. The entire flow of the stream 

at all stages passes under this bridge. High-water marks at the bridge 

indicate a maximum elevation of 17.5 feet on the gage. The stage of 

the stream is observed each morning and evening by the local gage 

reader, and current-meter measurements are made at intervals by the 

resident hydrographer.

ESOPUS CREEK AT KINGSTON, N. Y.

This gaging station was established at Washington avenue bridge 

in Kingston July 5, 1901, a view of which is shown in PL IV. This 

bridge has a clear span of 106.6 feet between abutments, which are 

nearly vertical. In addition there is on the left side a channel 19 feet 

in width through which water passes at high stages of the'river. Gage 

readings are made here each morning and evening. The bed is covered 

with small stone over part of the channel, the rest of the bed being 

made up of sand, silt, and small gravel.

WALLKILL RIVER AT NEW PALTZ, N. Y.

A gaging station is situated at the New Paltz highway bridge, a view 

of which is given in PI. V. The bridge is a span of 146.6 feet between 

the vertical faces of the masonry abutments. The entire flow passes 

under this bridge except in extreme freshets, when the left bank is 

overflowed.

The bed of the river is for the most part smooth, and composed of 

sand and silt.

RONDOUT CREEK AT ROSENDALE, N. Y.

A gaging station was established at the highway bridge at Rosendale, 

3 miles above the junction of the Wallkill, July 6, 1901. The bridge 

is a single span of 136 feet, and is shown in PL VI. The bed of the 

channel is rock with bowlders for 40 feet from right bank, the rest of 

the bed being covered with broken rock from 6 inches to 1 foot in 

diameter. The entire flow, aside from the diversion to the Delaware 

and Hudson Canal, passes under the bridge at all stages.

FISHKILL CREEK AT GLENHAM, N. Y.

A gaging station is located at the Newburg, Dutchess and Connecticut Railroad bridge, in Glenham. It was established July 8, 

1901. The bridge consists 6f the main central span with two auxil-
U. 8. GEOLOGICAL SURVEY

WATER-SUPPLY PAPER NO. 76 PL. VI

GAGING STATION ON RONDOUT CREEK AT ROSENDALE, N. Y.
U. S. GEOLOGICAL SURVEY WATER-SUPPLY PAPER NO. 76 PL. VII

GAGING STATION ON HOUSATONIC RIVER AT GAYLORDSVILLE, CONN.
PRESSEY.] VERTICAL VELOCITY CURVES. 29

iary overflow channels at the ends, the length of span being as follows: Left overflow, station zero to 22.5; main span, station 27.5 to 

station 122; right overflow, station 127 to station 149. The bed of 

the main channel is earth and gravel; that of the overflow channels 

is broken stone.

TENMILE RIVER BELOW DOVER PLAINS, N. Y.

A gaging station was established September 16, 1901, at Tabor's 

bridge, which crosses Tenmile River about 2,000 feet below the point 

of inflow of Swamp River. The gaging station is situated about 2 

miles below Dover Plains Village. Tabor's bridge consists of a single 

span, 85 feet between abutments. The bridge stands square across 

the stream, the bed of which is sand and gravel. The entire flow 

passes between the abutments of this bridge, except at the time of 

extreme high water, which occurs nearly every spring when the river 

overflows its banks, and some water passes around one end of the 

bridge.

HOUSATONIC RIVER AT GAYLORDSVILLE, CONN.

A gaging station was established at Gay lords ville, Conn., October 

24, 1900. The station is situated 3 miles east of the New York State 

line and 2 miles below the mouth of Tenmile River. Owing to the 

unfavorable conditions under the bridge, the discharge measurements 

are made from a cable of 200 feet span placed across the stream 1^ 

miles below the bridge. A view of the river at this point is shown in 

PI. VII. The cable is supported on the right bank by timber shears 

25 feet high and is anchored to a large buried rock. On the left 

bank a sycamore tree serves as a support for the cable, which is 

anchored to the base of a large oak.

DISCUSSION OF TABLES.

In the tables that are given in the following pages the measurements recorded were taken at the time of the regular gagings of the 

rivers, and with the same degree of accuracy with which currentmeter measurements have been made upon these streams. Only one 

instrument was used at one time, the velocity being taken at the 

various points in regular order vertically, usually at intervals of onehalf foot. When other space intervals were used it is shown in the 

tables.

In PI. VIII is shown the variation in the velocity of Wallkill River 

at New Paltz. The dotted lines are lines of equal velocities and are 

determined by observations of velocity at regular intervals throughout
30 FLOW OF EIVEES NEAR NEW TOEK CITY. [NO,T6.

the cross section. The line marked " mean velocity for each section" 

shows the depth at which may be found the filament of mean velocity. 

Near the right bank there is slack water and some return current, 

which accounts for the peculiar position of the curve, and the fact 

that there are two lines^of mean velocity. This condition would not 

usually occur at a gaging station.

At the bottom of PL VIII are lines showing the velocity at various 

depths, as 1 foot, 2 feet, etc., across the river section. The effect of 

the ledge of rocks is clearly shown in the plate.

A small Price current meter was used, and was in each case suspended from a bridge and hung freely in the water. The meter was 

held fifty seconds at one point to determine the velocity, and in 

each case the first reading was checked by a second, and if there was 

a discrepancy a third reading was taken. The results were plotted 

upon cross-section paper, the depths as ordinates and the velocities as 

abscissas, and a smooth curve drawn through the points, so that in 

case there was an error of sufficient magnitude to affect the final results 

it would be found when the curve was plotted. Before the work was 

commenced, and after the completion of these curves, the meter was 

rated and showed very slight change in its readings. The gage height 

was read at the beginning of each measurement and at its completion, 

and in general no change of stage of the stream during the measurement was noted.

In Table I the date of each measurement is given at the head of the 

column, then the point of measurement that is, the distance in feet 

from the initial point of soundings which had been previously established and marked permanently on the bridge. Next is given the 

gage height at the time the velocities were measured and the depth of 

water at the point of measurement at the time of making the measurement. The character of the bed of the river and the force and direction of the wind are also given. The depths, as given in the alternate 

columns, were measured by a wire attached to the meter and a tape. 

The column headed '' Velocities" gives the actual observed velocity 

in feet per second at each observation.

Table II is computed from Table I, the observations being the same, 

but the velocities being given at regular depths as shown in percentages of the whole in the first column. The velocities as shown in the 

columns of this table were found from the plotted vertical velocity 

curves based upon the figures in Table I, the velocities at each depth 

being taken by scale directly from the curve. The sum of the velocities in eacli column of Table II divided by 10 gives the mean velocity 

in that section, and is the quantity that should be obtained by a single 

meter observation at a point in the section which represents the point 

of mean velocity. For comparison, the velocity as actually found at 

six-tenths of the depth is given at the bottom of Table II, from, which
Velocity in second-feet Depth in faet.

52- 30 

O <

oC?

(/) O H -n

3?

c m

q 

3?

R E

v> o

> c

o z

m s

H m

' to
PBBSSBY.] VERTICAL VELOCITY CURVES. 31

it will at once be seen that the error in measuring the velocity at 

six-tenths depth is in general only slight on a stream of the general 

character of the Esopus.

Tables III, V, VII, IX> XI, and XIII show the results of the measurements on the Rondout, Wallkill, Catskill, Fishkill, Tenmile, and 

Housatonic, respectively; Tables IV, VI, VIII, X, XII, and XIV show 

the data obtained from the preceding tables, and were derived by the 

same method as Table II from Table I.
TABLE I. Velocities in vertical sections on Esopus 

July 19. 

90. 

4.40. 

6.4.

Silt and 

gravel.

Strong. 

Upstream.

1

Feet.

0.4

.9

1.4

1.9

2.4

3.9 

3.4 

3.9 

'4.4 

4.9 

5.4 

5.9

Velocity.

Feet

per 

sec.

0.77

.77

.73

.71

.70

.66

.61 

.57 

.57 

.48 

.54 

.54

Aug. 10. 

90. 

4.85. 

6.2.

Silt and 

gravel.

Gentle.

Downstream.

i

Q

Feet.

0.2

. 7

1.2

1.7

2.2

2.7 

3.2 

3.7 

4.2 

4.7 

5.3 

5.7

Velocity.

Feet

per 

sec.

1.03

1.00

1.03

1.05

1.00

.98 

.91 

.86

.77 

.75 

.68 

.63

Aug. 19. 

95. 

4.60. 

5.7.

Silt and 

sand.

Light. 

Upstream.

"ft 

Q

Feet.

0.2

.7

1.2

1.7

8.2

3.7 

3.3 

3.7 

4.3

4.7 

5.3

Velocity.

Feet

per 

sec.

0.83

.89

.82

.88

.86

.83 

.75 

.68 

.67 

.65 

.61

Aug. 29. 

75. 

5.50. 

4.4. 

Bowlders.

Gentle.

Downstream.

i

Q

Feet.

0.2

.7

1.2

1. 7

2.2

2.7 

3.2 

3.7 

3.9

Velocity.

Feet

per 

sec.

1.44

1.45

1.38

1.29

1.31

1.19 

1.05 

.89 

.68

Aug. 

80. 

5.50

6.1

Bowld

Gent

Dow

strea

!

Feet.

0.3

.7

1.2

1.7

2.7

3.7

4.7 

5.6

F
* Depth ..........................................

<i

3S

^ Direction of wind......... _ ..................

^

0

Oct. 16. 

40. 

6.64. 

4.0. 

Bowlders.

None.

!

Feet.

0.5

1.5

3.4

2.5

3.0

3.5

Velocity.

Feet

per 

sec.

2.26

2.29

2.12

2.07

1.52

1.35

Oct. 16. 

90. 

6.64. 

8.6.

Silt and 

gravel.

None.

i

Q

Feet.

0.5

1.5

2.5

3.5

4.5

5.2

5 5

6 5

7 5

81

Velocity.

Feet

per 

sec.

1.89

1.86

1.86

1.79

1.74

1.65 

1.57

1.42

1 32

1.15

Oct. 21. 

90. 

5.56. 

7.4.

Silt and 

gravel.

Q-entle. 

Upstream.

! a

Feet.

0.5

1.5

2.5

3.5

4.4

4.5 

5.5

6.5

7.0

T

Velocity.

Feet

per 

sec.

1.43

1.37

1.32

1.22

1.10

1.07 

.97

.85

Nov. 1. 

80. 

4.74. 

5.0. 

Bowlders.

None.

f® 

fl

Feet.

0.5

1.5

2.5

3.0

3.5

4.5

Velocity.

Feet

per 

sec.

0.98

.92

.91

.91

.87

.60

Nov

95

4.7

5

Silt 

san

No

da

05 

fl

Feet.

0.5

1.5

2.5

3.5

3.5

4.5

5.4
TABLE II.- Velocities at regular intervals in vertical sections on Esop

[Velocities in feet per second.]

Depth in parts of total.

0.05 .... . ...........................

.15.............................................

. 25. ....... ................................. ...

.45.............-.-...--....-- ---............

.65...................-.--.-.....---.--- ....

.85---....... .................... ............ 

. 95... ......................................... _

. 60 ..............................................

July 19

0.77

.76

74

71

68

64

60

56

.52 

43

.64

63

si

1.02

1.04

1.05

1.02

.96

.90

.83

.76

.68 

.60

.89

.87

O!

si

0.83

.87

.87

.85

.82

.77

.73

.66

.60 

.51

.75

1

1.45

1.44

1.41

1.36

1.29

1 32

1.14

1.02

.85 

.56

1.17

1.18

si

1.48

1.51

1.47

1.42

1.37

1.30

1.33

1.14

1.05 

.94

1.29

1.26

|

1.34

1.38

1.35

1.29

1.31

1.13

1.04

.94

.83 

.69

1.12

1 09

»

02

1.40

1.38

1.35

1.29

1 22

1.64

1.06

.98

.89 

.79

1.15

1.11

ed 

-t-I

1.45

1.46

1.44

1.42

1.40

1.37

1.32

1.25

1.17

1 ft9

1.33

1 34

53

02

0.85

.88

.90

.89

.86

.81

.73

.63

.48 

27

.73

.77

Character of the bed: From station 0 to 86 broken rock from. 0.5 feet to 1.0 foot in diameter. 

silt, and small gravel. From 105 to 116 broken rock 0.5 feet to 1.0 foot in diameter.
TABLE III. Velocities in vertical sections on Eondo

Date--........-...-.

Point of measurement

"Wind force...........

Aug. 8. 

90. 

7.50. 

7.2. 

Bowlders. 

None.

I 

&

Ft.

0.2

.7

1.2

2.2

3.2

4.0 

4.2 

5.2 

6.2

6.7

Velocity.

Feet

per 

sec.

1.70

1.60

1.65

1.54

1.33

1.29 

1.24 

1.00 

.98 

.86

Aug. 8. 

105. 

7.50. 

5.9. 

Bowlders. 

None.

f

Ft.

0.2

1 2

2.2

3.2

4.2

5.2

Velocity.

Feet

per 

sec.

1.33

1.43

1.22

1.24

1.05

.75

Aug. 8 . 

45. 

7.15. 

5.2. 

Bowlders. 

None.

P

Ft.

0.2

.7

1.2

1.7

2.2

3.2 

4 2

Velocity.

Feet

per 

sec.

1.29

1.40

1.42

1.44

1.40

1.14 

.89

Sept. 4. 

35. 

7.55. 

"4.7. 

Rock. 

Gentle.

Downstream.

"ft

01

P

Ft.

0.2

1.2

3.2

3.2

4.2

-----

Velocity.

Feet

per 

sec.

1.58

1.52

1.49

1.44

1.19

......

Sept. 24 

75. 

6.45. 

5.6. 

Bowlders. 

Gentle.

Downstream.

f

Ft.

0.3

1.0

2.0

3.0

3.4

4.0 

5.1

Velocity.

Feet

per 

sec.

0.51

.52

.50

.47

.46

.43 

.30

Oct. 11. 

65.

6.47. 

5.6. 

Bowlders. 

Gentle.

Upstream.

A

I

Ft.

0.5

1.5

2.5

3.4

3.5

4.5 

5.1

Velocity.

Feet

per 

sec.

0.55

.52

.52

.45

.40

.32 

.37

Oct. 11. 

75. 

6.47. 

5.6. 

Bowlders. 

Gentle.

Upstream.

1 

P

Ft.

0.5

1.5

3.5

3.4

3.5

4.3 

5.1

Velocity.

Feet

per 

sec.

0.60

.55

.47

.47

.42

.35 

.25
TABLE IV. Velocities at regular intervals in vertical sections on Rondout Cree

[Velocities in feet per second.]

Depth in parts of total.

.15.......................................

25

. 35. ............................. --......

.45..........--. ......................

.55...,......... ....................

. 65. ........ ......... ......- _ _

.85--..- --... -.------..-- 

.95.-..--..---.--.- . . ..

. 60... .. ........... --.___-.-.-.......

Aug. 8.

1.65

1.66

1.59

1.50

1.40

1.29

1.18

LOT

.95

.81

1.31

1.24

Aug. 8.

1.36

1.39

1.37

1.34

1.28

1.21

1.11

.99

.82

.63

1.15

1.16

Aug. 8.

1.33

1.40

1.43

1.40

1.33

1.23

1.10

.97

.83

.68

1.17

1.17

Sept. 4.

1.57

1.57

1.55

1.53

1.50

1.47

1.49

1.35

1.28

1.16

1.44

1.45

Sept. 24.

0.51

.52

.52

.51

.49

.47

.44

.40

.34

.26

.44

.46

Oct. 11.

0.55

,55

.54

.52

.50

.46

.41

.36

.30

21

.44

.44

O

Character of bed: From station 0 to 40, rock bed with some bowlders; from station 40 to bank, b
TABLE V. Velocities in vertical sections on Wallki

Point of measurement..

Aug. 10.

TO.

10.0.

9.8.

sat.

Gentle.

Depth.

Feet.

0.3

1.0

2.0

3.0

4.0

5.0

6.0

7.0

8.0

9.0

Velocity.

Ft. per 

sec.

3.00

3.05

2.77

2.91

3.86

3.86

2.58

2.47

2.35

1.88

Oct. 1.

70.

-.36.

7.5.

Silt.

Gentle.

Depth.

Feet.

0.3

1.3

2.3

3.3

4.3

4.5

5.3

6.3

6.9

Velocity.

Ft. per 

sec.

1.79

1.70

1.67

1.60

1.50

1.52

1.40

1 33

1.15

Oct. 9.

105.

6.48.

7.8.

Silt.

Depth.

Feet.

0.5

1.5

2.5

3.5

4.5

4.7

5.5

6.5

7.3

Velocity.

Ft. per 

sec.

1.22

1.15

1.12

1.12

1.08

1.05

.97

.87

.50

Oct. 24.

80.

6.33,

6.4.

Silt.

Depth.

Feet.

0.3

0.8

1.5

2.5

3.5

3.8

4.5

5.5

5.8

Velocity.

Ft.perf 

sec.

a 89

.91

.86

.77

,70

.75

.65

.47

.37

Oct. 24.

105.

6.33.

r.6.

Silt.

Depth.

Feet.

0.5

1.5

2.5

3.5

4.5

4.6

5.5

6.5

Velocity

Ft. p

sec.

0.9

.9

.9

.9

.9

.9

.8

.7

.6
TABLE VI. Velocities at regular intervals in vertical sections on Wallkill Riv

[Velocities in feet per second.]

Depth in parts of total.

0.05................. ..... .......................................

.15 ......................................................... ......

25

.85.. . . ....... .. .. - . - ....-...

.45..... .. ... _ - -.-.... ..- - ..

.55..... ...................- .............. ....................

.65--.--.-.----------------- ........... ....................

.75...................- ... .. ........................ ........

.85.--. ......................................................

.95. .. -... ........... ... ..- ...... ..................

.60......... _. _......... __-__ _ ..____._._ __ .

Aug. 30.

3.00

3.04

2.99

2.91

2 82

2 72

2.60

2 44

2.20

1.88

2.66

2.66

Oct. 1.

1.77

1.75

1.70

1.66

1.59

. 1.52

1.45

1.37

1.27

1.13

1.52

1.49

Oct. 9.

1.33

1.18

1.14

1.13

1.10

1.07

1.03

.95

82

46

1.01

1.05

Oc

Character of bed of stream: At all of the above stations the bed of the creek is smooth, compose
TABLE VII. Velocities in vertical sections on Catskil

Date. ------------

Point of measurement .

Gage height.. . .........

July 20 

55.

3.60. 

3.6. 

Bock.

None.

P

Ft.

0.3

.5

1.0

1.5

2.0

2.5

3.0 

3.1

Velocity.

Ft.

per 

sec.

1.67

1.72

1.54

1.52

1.47

1.21

1.07 

1.13

July 25 

55.

3.00. 

2.9. 

Bock. 

Gentle.

Downstream.

i& 

p

Ft.

0.3

.5

1.0

1.5

1.7

2.0

2.4

Velocity.

Ft.

per 

sec.

0.75

.77

.75

.63

.59

.52

.45

July 25 

45.

3.00. 

3.6. 

Bock.

Gentle.

Downstream.

I

Ft.

0.2

.5

1.0

1.5

2.0

2.2

2.5 

30

Velocity.

Ft.

per 

sec

0.66

.63

.66

.57

.57

.61

.50 

.50

Aug.l. 

55,

2.80. 

2.7. 

Bock. 

Strong.

Downstream.

i

Ft.

0.2

.5

1.0

1.5

1.6

2.0

2.2

Velocity.

Ft.

per 

sec.

0.52

.50

.45

.43

.43

.36

.35

Aug.l. 

60.

2.80. 

2.7. 

Gravel. 

Strong.

Downstream.

"p. 

&

Ft.

0.2

.5

1.0

1.5

1.6

2.0

2.2

Velocity.

Ft.

per 

sec.

0.48

.48

.43

.36

.38

.25

.25

Aug. 9. 

50.

3.00. 

3.1. 

BocX 

Gentle.

Upstream.

P

Ft.

0.2

.7

1.3

1.7

2.0

2.2

2 7

Velocity.

Ft.

per 

sec.

0.61

.67

.66

.59

.50

.54

.54

Aug. 23. 

60.

3.12. 

2.9. 

Gravel. 

Gentle.

Downstream.

!

Ft.

0.3

.8

1.3

1.8

2.3

2.8

----

...... r -

Velocity.

Ft.

per 

sec.

1.05

1.03

.99

.73

.57

.34

Sept

35

3.00

4.4

Grav

Gent

Up

strea

t

$ 

P

Ft.

0.3

.7

1.2

1.7

2.2

2.7

3.2

37

F

p

s

0
TABLE VIII. Velocities at regular intervals in vertical sections on Catskill Creek 

[Velocities in feet per second.]

Depth in parts of total.

0.05. ...................... .....

.15............................

.25. ..--....- ... ......

.45...... ...... ................

.55................ ............

.65.................. ..........

.75............................

.85...........................

.95.-.... ...................

.60-.-..---...------. --...

July 20.

1.69

1.70

1.65

1.58

1.50

1.41

1 32

1 21

1.10

at

1.41

1.37

July 25.

0.75

.76

.76

.73

.68

.62

.56

.50

43

.36

.61

.59

July 25.

0.64

.65

.65

.63

.60

.57

.54

.50

46

40

KCJ.

.56

Aug. 1.

0.52

.51

.50

.48

.45

.42

.38

.32

26

.18

40

40

Aug. 1.

0.48

.49

.47

.44

.41

.37

.32

.27

.21

.14

.36

.35

Aug. 9.

0.65

.68

.68

.67

.65

.61

.57

.52

.47

40

.59

.59

Aug. 23.

1.06

1.05

1.03

.98

.92

.84

.74

.62

50

.36

.81

.80

Sep

Character of river bed: Prom station 0 to 55 the bed is a rock ledge, and from station 55 to the le
TABLE IX. Velocities in vertical sections on Fishkill 

Point of measureGage height, feet ..-.

July 24.

51. 

3.60. 

3.6. 

Gravel. 

Gentle.

Upstream.

£

P5T 

Q

Ft.

0.2

.7

1.2

1.7

2.2

2.7 

3.1

Velocity.

Ft. 

per 

sec.

0.54

.54

.45

.38

.38 

.39

.27

Aug. 15.

50. 

3.85. 

4.0. 

Gravel. 

Strong.

Downstream.

3 

ft

Q

Ft.

0.2

.7

1.2

1.7

2.2

2.4 

2.7 

8,71

Velocity.

Ft. 

per 

sec.

0.75

.75

.73

.68

.66 

.66 

.54 

.45

Aug. 15.

55.

3.85. 

3.1 

Gravel. 

Strong.

Downstream.

i

Q

Ft.

0.2

.7

1.2

1.7

2.-S

2.7

Velocity.

Ft. 

per 

sec.

0.73

.75

.71

.68

' .63 

.59

Aug. 30.

45. 

4.60.

4.4. 

Gravel. 

Gentle.

Downstream.

5

Q

Ft.

0.2

.7

1 2

1.7

3.2 

2.7

3 71

3 7

3 9

Velocity.

Ft. 

per 

sec.

1.70

1.89

1.87

1.96

1.79 

1.75 

1.61

1.49

1.29

Aug. 30.

50. 

4.60. 

4.4. 

Gravel. 

Gentle.

Downstream.

4 § 

Q

Ft.

0.2

.7

1.2

1.7

2.2

2.7 

3?l

3 7

39

Velocity.

Ft. 

per 

sec.

1.42

1.77

1.75

1.72

1.67 

1.61 

1.52

1.30

1.03

Aug. 30.

55.

4.60. 

4 2 

Gravel. 

Gentle.

Downstream.

4&

Q

Ft.

0.2

.7

1.2

1.7

2.2

2.7 

3?l

3 7

Velocity.

Ft. 

per 

sec.

1,47

1.75

1.70

1.67

1.61 

1.54 

1.54

1 3ft

Sept. 6.

60. 

4.15. 

3.8. 

Gravel. 

None.

\

i

Q

Ft.

0.2

.7

1.2

1.7

2.2 

2.7 

33

Velocity.

Ft. 

per 

sec.

1.05

1.17

1.17

1.14

1.03 

.94 

.73

F

0

1

1

2

2
TABLE X. Velocities at regular intervals in vertical sections on FisJikill Cree

[Velocities in feet per second.]

Depths in parts of total.

0.05---... ........ ................... ......

.15.......................................

.25.... ....... ................. ...........

.35.. .....................................

.45.......................................

.55.......................... ............

.65.......................................

.75........................ ..............

.85.......................................

.95.......................................

.60..... ..................................

July 24.

0.54

.54

.51

.47

.43

.39

.34

.29

23

.16

.39

.37

Aug. 15.

0.75

. .75

.74

.72

.68

.63

.56

48

40

.30

.60

60

Aug. 15.

0.74

.75

.74

.72

.70

.67

.63

.59

.55

.51

.66

.65

Aug. 30.

1,77

1.87

1.92

1.91

1.86

1.78

1.69

1.59

1 45

1.36

1.71

1.74

Aug. 30.

1.64

1.74

1.75

1.73

1.69

1.64

1.58

1.50

1.38

1.15

1.58

1.61

Aug. 30.

1.63

1.71

1.71

1.68

1.64

1.60

1.56

i \i

1.44

1.32

1.58

1.58

Se

Character of bed of creek; Bowlders from 0.2 foot to 0.6 foot in diameter.
PRESSEY.] ' VERTICAL VELOCITY CURVES. 43 

TABLE XI. Velocities in vertical sections on Tenmile River at Dover Plains.

Date...............

Point of meastireDepth. ..... ....

Wind............

Direction ........

Oct. 15.

55. 

7.19. 

6.8. 

Sand. 

Fresh. 

Downstream.

Depth.

Feet.

0.5

1.5

2.5

3.5

4.1

4.4

5.3 

6.3

Velocity.

Ft. per 

sec.

a. 43

2.38

2.31

2.19

2. 17

2.09

2.00 

1.84

Oct. 26.

25.

5.01. 

4.6. 

Sand. 

None.

Depth.

Feet.

0.3

.8

1.3

1.8

2.3

2.8

8.3

4.1

Velocity.

Ft. petsec.

1.10

1.07

1.00

.92

.90

.82

.75 

.63

Oct. 26.

55. 

5.01. 

4.8 

Sand. 

None.

Depth.

Feet.

0.5

1.5

2.5

2.9

3.5

4.3

........

Velocity.

Ft. per 

sec.

1.00

.95

.93

.92

.90

.77

--------

Nov. 11.

25.

4.75. 

4.4. 

Sand. 

None.

Depth.

Feet.

0.4

.9

1.4

2.0

2.6

3.0

3.5 

3.9

Velocity.

Ft. per 

»ec.

0.90

.87

.77

.70

.67

.61

.55 

.50

Nov. 22.

25. 

4.76. 

4.2. 

Sand. 

Gentle. 

Downstream.

Depth.

Feet.

0.3

.8

1.5

2.0

2.5

3.0

3.5

3.7

Velocity.

Ft. per 

sec.

0.84

.84

.73

.75

.67

.56

.55 

.49

TABLE XII. Velocities at regular intervals in iiertical sections on Tenmile River 

at Dover Plains, deduced from data in Table XI.

[Velocities in feet per second.]

Depths in parts of total.

0.05...............

.15.. ..................................

.25... .................. .... . .....

.85.......................................

.45.-.--.. ........ ........................

.55 -.-. . . . .

.65-...--.-. ............................

.75..... ......... ..........

.85. .. ....

.95..... ..................................

Mean...............................

.60.-....-..-.. ...........................

Oct. 15.

2 44

2 42

2.36

2.30

2 23

2.16

2.09

2.02

1.95

1.83

2.18

3.13

Oct. 26.

1.08

1.06

1.03

.98

.93

.87

.81

.73

.65

46

.86

.84

Oct. 26.

0.99

.99

.98

.97

.95

.93

Q1

.88

.82

.68

.91

.92

Nov. 11.

0.89

.86

.83

.79

.75

.70

64

.58

52

.44

.70

.67

Nov. 22.

0.84

.84

82

.78

.74

.70

.65

.59

.51

.43

.69

.68
44 FLOW OF EIVEES NEAB NEW YOEK CITY. [NO.76. 

TABLE XIII. Velocities in vertical sections on Housatonic River at Gaylordsville.

Date.. -_...__.___.-_---

Point of measurement- . _ _ -

Wind.. .....................

Aug. 8.

60.

3.50.

3.8.

Depth.

Feet.

0.20

.30

.8

1.3

1.8

2.3

2.8

3.3

Velocity.

Ft. petsec.

2.19

2.23

2.25

2.14

2.07

2.05

1 72

1.35

Oct. 29.

60.

4 05

4.8.

Depth.

Feet.

0.5

1.5

2.5

3.9

3.5

4.3

Velocity.

Ft. per

sec.

2.98

2.90

2.85

2.68

2.39

1.92

Nov. 13.

60.

4.82.

6.2.

Depth.

Feet.

0.5

1.5

2.5

3.5

3.7

4.5

5.6

Nov. 23.

60.

4.11.

4.8.

1

Velocity.

Ft. per

sec.

3.84

3.93

3.84

3.50

3.44

3.23

2.50

Depth.

Feet.

0.5

1.5

2.5

2.9

3.5

4.3

Velocity.

Ft. per

sec.

3.03

2.92

2.81

2.61

2.38

1.90

TABLE XIV. Velocities at regular intenials in vertical sections on Housatonic 

River at Gaylordsville, deduced from data in Table XIII.

[Velocities in feet per second.]

Depths in parts of total.

0.05............:......................................

.16....................... _.__ --_. - .

25

.35..... - --- .- -......-.- -- --

. 45 -. ---...-.. .-..-.. .......-..-.-. -- --..

.55.. ..- -- - -- --- - -- 

65

TC

. 85.. ............................................. _..-

.95..- -.---- - -- --- -- .- 

60

Aug. 8.

2.21

2.23

2.21

2.17

2.10

2.02

1.85

1.66

1.45

1.20

1.91

1.94

Oct. 29.

3.00-

2.97

2.94

2.90

2.85

2. 77

2. 57

2.35

2.10

1.75

2.62

2.67

Nov. 13.

3.89

3.90

3.91

3.89

3.79

3.60

3.38

3.11

2.79

2.04

3.43

3.49

Nov. 23.

3.02

3.01

3.00

2.94

2.85

2.72

2.52

2.34

2.10

1.80

2.63

2.62

For the purpose of comparison a mean curve for each of the streams 

has been determined by taking the mean of all the velocities shown in 

each of Tables II, IV, VI, VIII, X, XII, and XIV. To facilitate comparison, the data for these mean curves have been expressed in percentages of the mean velocity in a vertical section, and are shown in 

Table XV, the total number of curves being 78. By this arrangement a 

figure in the column greater than 100 shows a velocity greater than the 

mean in the vertical section being considered, and a velocity less than 

100 shows a velocity less than the mean. The mean curves have been 

plotted in fig. 2. It will be seen from these curves that the general 

character of the vertical velocity curves is much the same in each
PRESSEY.] VERTICAL VELOCITY CURVES.

case, showing fairly conclusively that we may prophesy as to the 

general character of the vertical velocity curve in natural streams 

with steep banks and from smooth to moderately rough bottoms, and 

depths of from 3 to 8 feet. It will be noted that the ratio of the mean 

velocity to the surface velocity varies from 92 per cent on the Fishkill 

to 82 per cent on the Catskill, and that the maximum velocity of these 

streams varies from 13 to 25 per cent greater than the mean, and that 

at no point do all of the curves fall so closely together as at six-tenths 

depth. At that point the greatest variation from the mean is 2^ per 

cent. This shows that the measurements made at six-tenths depth 

were subject to less variation than those made at any other point, 

and that in general, on streams of the character here represented, a 

measurement made at that point would represent approximately the 

mean velocity in the section. It will be noted that none of the curves 

cross the line of mean velocity at a greater depth than 0.63, nor at a 

less depth than 0.56, showing that the point of mean velocity on these 

streams lies between these two depths.

TABLE XV. Averages of velocity curves expressed in terms of -mean velocity in a 

vertical section (represented as 100).

No. of velocity 

curves.

Bed of stream. _ _

Mean depth.....

Depth below 

surface in 

parts of total: 

0.05..........

.15.... ___..-

.35.. ........

.35-.--.....

. 45.. ....... .

.55..........

. 65. ........ .

.75____--..__

. 86.... ......

.95 .___......

Mean

. 60.. .......

12.

Small 

gravel.

6.5.

118.6

120.8

118.9

115.0

109.3

103.3

94.4

85.5

74.9

60.3

100.0

98.9

8.

Bowlders.

4.7.

115.9

116.6

115.5

112.7

109.4

104. 8

98.6

89.7

77.8

59. &

100.0

101.7

20.

Average.

5.8.

117.3

118.8

117.3

113.9

109.3

103.5

96.4

87.5

76.3

59.7

100.0

100.2

dout.

13.

Bowlders.

6.

117.9

119.6

118.5

115.9

111.7

105.9

97.3

86.3

72.8

54.2

100.0

101.8

Wallkill.

9.

Silt.

7.3.

119.7

118.4

115.4

111.6

107.4

102.5

96.3

89.0

78.6

61.1

100.0

99.6

Catskill.

14.

Small 

gravel 

and 

rock 

ledge.

3.2.

134.7

124.8

131.8

116.5

109.7

101.5

92.5

81.9

70.7

55.9

100.0

97.2

FishMll.

13.

Large

gravel.

3.7.

110.7

113.7

113.4

111.3

108.2

104.0

98.3

91.0

81.2

68.2

100.0

101.4

Tenmile.

5.

Sand.

5.

116.8

115.6

112.7

109.0

104.9

100.4

95.5

89.9

83.3

71.9

100.0

98.1

tonic.

4.

Gravel.

4.9.

114.4

114.3

113.9

113.4

109.5

105.0

97.4

89.3

79.7

64.1

100.0

101.2

ofalltfie

streams.

78.

Various.

5.07.

117.0

117.9

116.3

113.2

109.0

103.6

96.5

87.9

77.2

61.4

100.0

 100.26

In Table XV, under the heading "Average of all the streams," the 

mean velocity of each depth given in the table is shown, and the curve 

representing this mean vertical velocity curve is platted in fig. 3 as a 

solid line. This curve represents the mean of 78 vertical velocity 

curves, the mean of the vertical velocity curves platted in fig. 2.
46 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. 76.

It will be noted in this curve that the relation between the mean 

velocity and the surface velocity is 87; that the maximum velocity is 

18 per cent greater than the mean, and that the point of mean velocity 

is almost exactly at six-tenths depth, the variation, as shown in the 

last column of Table XV, being about one-fourth of 1 per cent. This 

shows clearly that a measurement made at six-tenths of the depth of 

a stream having the general characteristics of those considered will 

in general represent closely the mean velocity in that section.

To show the relation between the velocity at mid depth and the 

mean velocity in a vertical section Table XVI has been compiled 

from Table XV. From this table it will be seen that, upon streams 

like these being considered, if the mid depth is known, the mean 

velocity in the vertical section may be found by applying a coefficient 

of 0.94.

TABLE XVI.- Relation between ^^elocity at mid depth to mean velocity in a vertical

section.

Stream.

Esopus . _ _ _ __ __.. _____ __ __ _____ . --._

Bondout __ __ _.___ ___ __ _ _ _._-__ _ _ _._ --.

Wallkill.. ____________ .____._._.._.._._.. ...........

Catskm.--- ................... ......................

Fishkill ........... ..................................

Housatonic _________________________________________

Velocity at 

mid depth 

expressed in 

percentage 

of the mean.

106.4

108.8

104.9

105. &

106.1

103.6

107.3

106.3

Coefficient to 

be applied to 

velocity at 

mid depth to 

obtain mean 

velocity.

0.94

.93

.95

.94

.94

.97

.93

.94

Humphreys's and Abbott's observations on the Mississippi River 

gave a coefficient of 0.98, while Ellis, on the Connecticut, found 0.94, 

and Wheeler and Lynch, on the Merrimac flume, found 0.95. It will 

be seen that there is a variation of 5 per cent on the streams being 

considered in this paper, and that the results of Humphreys and 

Abbott on the Mississippi and Ellis on the Connecticut vary from 

each other by 4 per cent, although the rivers are both large and have 

somewhat the same characteristics. In view of these facts, it seems 

that it is somewhat better to measure the velocity at the point of mean 

velocity than to measure the velocity at mean depth and apply a 

coefficient.

It is very evident that the character of the bed will affect to some 

extent the form of the vertical velocity curve. A rough bed would 

be expected to retard the velocity near the bottom of the stream. 

None of the streams under investigation may be considered to have 

extremely rough beds, but by comparison the beds of Rondout Creek
PRKSSKY.] VERTICAL VELOCITY CURVES. 47

and Housatonic River may be said to be rough, while those of the 

Wallkill River and Tenmile Creek are smooth at the point of measurement. Part of the bed of the Esopus is rough and part smooth. In 

order to determine the effect of the variation in the beds on the flow, 

the results in Table XV have been classified in Table XVII into 

streams with rough and smooth bottoms, the Rondout, Housatonic, 

and part of the curves on the Esopus being in the first column, and 

the Wallkill, Tenmile, and remaining observations on the Esopus in 

the second. The results shown in these two columns have been plotted 

in fig. 3.

It will be seen that the rough bed causes a drag at the lower end of 

the vertical velocity curve, due largely to eddies formed at the bottom of the stream. This retardation of the water near the bed of 

the stream causes the point of mean velocity in the vertical section 

to rise, and a measurement of velocity made at 0.60 depth will therefore be too small. With a smooth bed a measurement made at 0.60 

depth will, in general, be too large, the filament of mean velocity being 

nearer the surface. In other words, in making a measurement of 

mean velocity in a vertical section the meter should, in general, be 

suspended above 0.60 depth in streams of rough bed and below 0.60 

depth in streams of smooth bed. In the rivers here considered the 

variation of roughness of beds is so small in the different streams 

that the error in assuming the velocity at 0.60 depth to be the mean 

velocity in the vertical section would not be great, but in streams of 

very rough beds the variation would be more marked.

TABLE XVII. Relation betiveen velocities in vertical sections imth sjnooth and

rough bottoms.

Depth below surface in parts of total.

0. 05. ---.-.-.............--......_...............--.. .

.15.................................. ..............

.25.. ........................... .............. .. ...

.35.-..--..-....---. .................. .............

.45__ .............................................

.55....... .................................... -----

.65.,. ........ .....................................

.'75............................... ..................

.85... ................................ ..............

.95............-..-...-..-..-...-........-........:..

Mean ... ..........._ ___._.___ _ _ _ _ _ . . . . ....

.60. ..................................... ............

Smooth bottom: 

Esopus, Wallkill, Tenmile.

Velocity in percentage of the 

mean.

118.7

118.8

116.2

112.4

107.6

102.0

95.4

87.8

78.1

63.0

100.0

99.0

Bough bottom: 

Rondout, Housatomc.

Velocity in percentage of the 

mean.

116.2

117.0

116.0

113.8

110.3

105.3

97.7

88.3

76.5

58.9

100.0

101.6
48 FLOW OF EIVEES NEAE NEW YOEK CITY. [NO. 76.

FLOW OF RIVERS UNDER ICE, SMOOTH AND UNBROKEN

COVER.

It is frequently desirable to measure the flow of rivers and canals 

when they are covered with a coating of ice. It is quite clear that 

the same relations in various parts of the channel do not hold good 

when the channel is covered with ice as when the surface is open. 

The friction between the water and the ice retards the surface velocity, and it is possible that in a few cases the river may flow under a 

head if the ice cake is heavy and held firmly in position'. In making 

measurements of the flow of a river when frozen over, floats can not 

be used, and in general a current meter is the most serviceable 

instrument.

Distance from abutment in feet10

Depth 

in 

feet.

30"1 " 

o

CJ 

OJ

40 50 60 70 80 90 100

f 

ro <r> f 

- <a c <*)(*) 

J N <0 r 

3 Q °i C 

I 4 CO o

0 (J) 

D « 

rj CO

110

1 n N

CO

120

it

(vi

130 140

PIG. 4. Cross section of Wallkill River at New Paltz, showing ice cover and curves of equal 

velocity in river chaunel. (Note. Measurements taken January 23,1902; 117 measurements of 

velocity being made with the current meter; mean velocity, 3.23 feet per second; discharge, 

6,063 second-feet. The dotted line shows the position of mean velocity in the vertical section.)

During the winter of 1901-2 .observations to determine the change 

of velocity in a vertical plane below the ice were made on Wallkill 

River, and Esopus, Rondout, and Catskill creeks, and the data collected are presented in the following tables/* The observations were 

made by cutting holes through the ice large enough to admit a current 

meter. The thickness of the ice in each case is given in the table, 

and the fact that the water rose in most cases to a point about flush 

with the surface of the ice shows that there was some pressure upon 

.the flowing stream. It may be of interest in passing to note the distribution of the velocity in the cross section, as shown in flg. 4, the 

result of the gagings made on the Wallkill River at the New Paltz 

gaging station, January 23, 1902. The total area of the water section was 1,880 square feet, the mean velocity 3.23, and the discharge 

6,063 second-feet. One hundred and seventeen measurements were

«These observations were made incidental to the discharge measurements of the streams.
PRESSEY.] FLOW OF EIVEES UNDEE ICE. 49

made with the current meter, and the points are platted in the figure, 

the velocity in feet per second being noted beside each point. The 

mean velocity in feet per second in a vertical section is shown by the 

figures,across the top of the section. A dotted line showing the position of the mean velocity in the vertical sections has been drawn on 

the cross section. It will be seen that the maximum velocity occurs 

near the center of the channel, and at about mid depth, and that 

the effect of the ice covering is to form a covered fiunie, the curves 

of equal velocity being much the same as have been plotted occasionally for such flumes. The water just below the ice is so retarded that 

there are two points of mean velocity, as shown in figs. 4 and 5.

In the following tables are given the results of measurements made 

in vertical sections upon the above-mentioned rivers. These measurements were made with a single meter, the velocities being taken at 

intervals of from 1 to 2 feet, these distances being shown in each case 

in the table. Tables XVIII, XX, XXII, XXIV, and XXVI show the 

velocities as determined by actual measurements. At the head of the 

table are given the date, distance from initial point of sounding, gage 

height at the time of measurement, total depth of the river (including ice), the thickness of ice, and the depth of water under the ice. 

In every case the depth, as given in the body of the table, refers to 

the depth of water under the ice, the lower surface of the ice being 

considered as zero, and the distances being measured in feet and 

tenths. Where not otherwise stated, the ice was smooth on the lower 

side. Some curves were made with ice broken and tilted, but the 

results were quite different from those obtained with smooth ice, and the 

results have been given in separate tables (XXIX to XXXIII). The 

retarding influence of the rough ice was decidedly greater than that of 

the smooth ice and is so variable that no law can be formulated.

Tables XIX, XXI, XXIII, XXV, and XXVII ar<Tderived from the 

preceding tables by platting the vertical velocity curves, as shown by 

the original data, and taking from this curve the velocities at regular intervals, one-tenth of the depth apart. The sum of these velocities divided by 10 will give the mean in the section.

In Table XIX, and the others of a similar character, a column 

has been added, headed "Per cent of mean." The figures of this 

column,are obtained by dividing the corresponding figures in the adjacent column by the mean velocity, which reduces the data for each 

velocity curve to a similar curve whose mean is 100, and as the depths 

are then expressed as percentages of total depth, and the velocities 

as percentages of the mean velocity, the comparison between the 

curves is facilitated. In all cases for which the data are included 

within these tables the ice on the surface was smooth both on its 

upper and lower faces. The few velocity curves taken at times when 

the ice was broken and tilted are shown in separate tables. 

IRR 76 03 i
TABLE XVIII. Velocities in vertical sections wider 

1901-1903.

Date.. ................

Point of measureTotal depth ......_...

Dec. 11.

85. 

11. 50. 

12. !?. 

O.T. 

11.6.

A+3

!

Ft. 

0.8 

2.8 

4.8 

6.8 

8.8 

10.8

Velocity.

Ft. 

per 

sec.

2.52 

3.03 

3.11 

2.78 

2.38 

1.62

Dec. 11.

75. 

11. 50. 

12.2. 

0.7. 

11.5.

A 

%<E 

fl

Ft. 

0.8 

2.8 

4.8 

6.8 

8.8 

11.0

Velocity.

Ft. 

per 

sec.

2.43 

3.13 

3.18 

2.73 

2.43 

1.65

Dec. 11.

53. 

11.50. 

9.9. 

0.7. 

9.2.

!

Ft. 

0.8 

2.8

4.8 

6.8

8.7

Velocity.

Ft. 

per 

sec.

2.14 

2.68 

2.68 

2.71 

2.12

Dec. 11.

40. 

11.50. 

9.4. 

0.4. 

9.0.

f0>

Q

Ft. 

0.3 

1.3 

3.3 

5.2 

7.0 

8 5

1

Ft. 

per 

sec.

2.24 

2.64 

2.90 

2.76 

2 31 

1.62

Jan. 21.

50. 

7.24. 

4.6. 

1.2. 

3.4.

3

ft

i3

Ft. 

0.3 

1.3 

2.3 

2.8

Velocity.

Ft. 

per 

sec.

0.80 

.95 

.85 

.67

Jan. 21.

80. 

7.24. 

6.8. 

1.0. 

5.8.

3

1

Ft. 

0.3 

1.3 

2:3 

3.3 

4.3 

5.3

Velocity.

Ft. 

per 

sec.

0.77 

1.12 

1.22 

1.12 

1.00 

.77

Jan. 21.

90. 

7.24. 

7.6. 

1.0. 

6.6.

A 

£

i3

Ft. 

0.3 

1.3 

2.3 

3.3 

4.3 

5.3 

6.1

Velocity.

Ft. 

peisec.

0.62 

1 22 

1,25

1.20 

1.05

.87 

.70
Point of measure-

-

Jan. 23. 

90.

n. as.

IT. 7.

0.7.

ir.o.

f

Q

Ft. 

0.3 

1.1 

2.6 

4.2 

5.8 

7.4 

9.0 

10.5 

12.0 

13.5 

14.3 

16.0 

16.5

Velocity.

Ft. 

per 

sec.

3.23 

3.88 

4.21 

4.26 

4.30 

4.35 

4.26 

4.09 

3.95 

3.65 

3.53 

3.01 

2.52

Jan. 23. 

100.

17. as.

18.8. 

0.8. 

18.9.

a "a

33

Ft. 

0.3 

1.2 

2.3 

4.0 

5.7 

7.4 

9.1 

10.8 

12.5 

14.2 

15.9 

16.7 

17.5

Velocity.

Ft. 

per 

sec.

2.36 

3.58 

3.72 

3.93 

4.12 

4.17 

4.21 

4.17 

4.09 

4.05 

3.91 

3.70 

2.43

Jan. 23.

110. 

17.33. 

19.8. 

0.8. 

19.0.

! Q

Ft. 

0.7 

1.7 

3.4 

5.1 

6.8 

8.5 

10.2 

11.9 

13.6 

15.3 

17.0 

17.8 

18.5

Yelocity.

Ft. 

per

sec.

2.73 

3.03 

3.55 

4.02 

4.12 

4.17 

4.14 

4.09 

4.00 

3.88 

3.23 

2.94 

2.52

Jan. 31.

40. 

9.07. 

6.8. 

1.0.

5.8.

f

Q

Ft. 

0.3 

1.3 

2.3 

4.3 

5.3

Velocity.

Ft. 

per 

sec.

1.32 

1.65 

1.72 

1.52 

1.20

Jan. 31.

70. 

9.07.

8.8. 

1.0.

7.8.

3

ft

Q

Ft. 

0.4 

1.3 

2.3 

4.3 

6.3 

7 3

Velocity.

Ft. 

per 

sec.

1.98 

3.21 

2.43 

2.29 

1.79 

1.37

Jan. 31.

80. 

9.07. 

8.8. 

1.0.

:7.8.

t&

Ft. 

0.3 

1.3 

2.3 

4.3 

6.3 

7 3

Velocity.

Ft. 

per 

sec.

1.65 

2.31 

2.45 

2.31 

2.00 

1 63

Jan. 31.

90. 

9.07. 

10.0. 

1.0. 

9.0.

f

Q

Ft. 

0.3 

1.5 

3.5 

5.5 

7.5 

8 5

Velocity.

Ft. 

per 

sec.

1.70 

2.33 

2.45 

2.24 

1.72 

1.37

F

0

0

2

4

6

8

9 

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Velocity.

ATit T>AT* 

mean. of 

Velocity.

mean. of 

Velocity.

mean. of 

Velocity.j -p 

mean. of 

Velocity.j -p 

mean. of 

Velocity.

mean. of 

Velocity., -p 

mean. of 

Velocity,

mean. of 

Velocity.

mean. of 

Velocity.

mean. of 

Velocity.

mean. of 

Velocity.

cent Per 

mean. of 

Velocity.

cent Per 

mean. of 

OOCD O^1 t"" O

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1? i 

>s>. O 

to - ^^SS*


. S

li?

*~l*± $^>

&, aa

 ?*. ^

*S

s?

c?N^N
cent Per 

mean. of 

Velocity. to <-. o M to t8 

o o jo ^< 3 O 

cent irer 

mean. of 

Velocity.

cent Per 

mean. of 

Velocity.

* cen er ^* SESttSss °, 2 & s 3 H3 

to to to to to to 

cent Per 

mean. of co GC u* --^E ot o w il~ i H i^ o 

. to to to to to 

Velocity.

mean. of 

4 t- f8 tO IO tO to to M M M 

~'tiSr l| ~ l| ~ MI , ;-, hi 

mean. of coMi-iPMosao-^S^i o o 

. 10 tO to to to to 10 10 M 

mean. of 

Velocity.

S

i ' Cen 6r -^fCoO'oi-'i-'i-'MQrX 

mean. of co^tco-SitotncftH'Po 

Velocity.

cent r S P co P 5 S 

mean. of - ^ x 

O M M 

Velocity.

cent Per 

mean. of 

Velocity.

cent Per 

mean. of 

Velocity. co T coi$^rf~fcnoc5>oo

I ' t-0 H-" 00 & O to M 

§

saaAra

cent Per 

mean. of 
TABLE XX. Velocities in vertical sections under ic

Point of measurement . .

Total depth ...... ........

Jan. 9 

80. 

6.55. 

6.8. 

0.2. 

. . 6.6.

Depth.

Feet.

0.3

1.3

2.3

3.3

4.3

5.3 

6.1

Velocity.

Ft. per 

sec.

1.25

1.50

1.52

1.50

1.43

1.33 

1.10

Feb. 20 

80. 

5.38. 

5.8. 

0.1. 

5.7.

Depth.

Feet.

0.3

1.2

2.2

3.3

4.3

5.2

Velocity.

Ft. per 

sec.

0.67

.97

.91

.90

.87

.66

Feb. 28 

40. 

9.14. 

6.3. 

0.3. 

6.0.

Depth.

Feet.

0.5

1.5

2.5

3.5

4.5

5.5

Velocity.

Ft. peisec.

2.56

3.01

2.99

2.90

2.29

1.65

Dec. 4 

90. 

5.28. 

6.85. 

0.05. 

6.8.

Depth.

Feet.

0.5

1.5

2.5

3.5

4.1

4.5 

5.6 

6.3

Velocity.

Ft. per 

sec.

0.72

.85

1.05

1.10

1.09

1.00

.82 

.59

Depth

Feet.

0.5

1.5

2.5

3.0

3.5

4.5

a Bed of river 40 to 80 is bowlders, 90 to 100 
TABLE XXI. Velocities at regular intervals in vertical sections on Esopus Cr

[Velocities in feet per second.]

1 

Depth in parts of total, a

o.m. ......................

.15 ....................

.35.......... ...........

.35.......................

.45.--....--....------...

.55-....------...--..--.

.65 . ............... --

.75. ... . ........ .....

.85---... .. ...........

.95.. ........ ..........

Jan. 9.

Velocity.

1.26 

1.45 

1.53 

1.53 

1.51 

1.49 

1.44 

1.37 

1.36 

1.02

1.385

Per 

cent of 

mean.

91 

105 109' 

110 

109 

107 

105 

99 

91 

74

100

Feb. 30.

Velocity.

0.67 

.85 

.94 

.95 

.93 

.91 

.88 

.83 

.75 

.59

.83

Per 

cent of 

mean.

81 

102 

113 

114 

112 

110 

106 

100 

91 

71

100

Feb. 28.

Velocity.

3.40 

3.75 

 3.00 

3.08 

3.03 

2.88 

2.70 

2.45 

2.07 

1.45

2.58

Per 

cent of 

mean.

93

107 

116 

119 

117 

112 

105 

95 

80 

56

100

Dec. 4.

Velocity.

0.67 

.82 

.94 

1.03 

1.09 

1.10 

1.05 

.92 

.77 

.53

.89

Per 

cent of 

mean.

75 

93 

106 

116 

122^ 

132 

118 

102 

86 

60

100

Veloc

0

1

1

1

 1

1

1

a The lower surface of the ice is zero de
TABLE XXII. Velocities in Vertical sections under ic

Point of measurement. . .

*

80.

6.80.

6.2.

0.1.

6.1.

Depth.

Feet.

0.4

1.4

3.4

3.4

4.5

5.6

Velocity.

Feet per 

sec.

0.62

.73

.77

.71

.62

.51

Dec. 6.

90.

6.80.

6.6.

0.3.

6.4.

Depth.

Feet.

0.3

1.3

2.3

3.3

4.4

5.9

Velocity.

Feet per 

sec.

0.55

.70

.65

.61

.55

.45

Jan. 14.

80.

7.00.

6.5.

0.2.

6.3.

Depth.

Feet.

0.8

1.8

2.8

3.8

4.8

5.8

Velocity.

Feet per 

sec.

1.05

1.32

1.47

1.40

1.35

1.07

Jan. 14.

90.

7.00.

7.0.

0.2.

6.8.

Depth.

Feet.

0.8

2.3

3.3

4.3

5.3

6.3

Velocity.

Feet per 

sec.

1.07

1.27

1.27

1.15

1.10

1.07

F

- 

Depth

Feet.

0.3

1.5

2.5

3.5

4.6

5.7

"Bed of creek is rock, with some bowlders from 0 to 40 and broken rock from 0.6 t
TABLE ILKUI.^Velocities at regular intervals in vertical sections on Rondout C

[Velocities in feet per second.]

Depth in parts of total, «

0.05.......................

.15.......................

.35. ......................

.35.......................

. 45. ............ .-TT..... .

.55......................:

.65.......................

,75........................

.85.......................

.95.......................

yer i

Dec. 6.

Velocity.

0.61 

.68 

.75 

.76 

.75 

.72 

.67 

.68 

.55 

.45

.66

Per cent 

of mean.

93

104 

114 

116 

114 

110 

103 

94 

84 

69

100

Dec. 6.

Velocity.

0.55 

.65 

.68 

.67 

.64 

.61 

.57 

.53 

.48 

.40

.58

Per cent 

of mean.

95 

112 

117 

116 

111 

106 

99 

91 

83 

70

100

Jan. 14.

Velocity.

0.85 

1.09 

1.27 

1.40 

1.47 

1.46 

1.41 

1.31 

1.18 

.96

1.24

Percent 

of mean.

69

88 

102 

113 

119 

118 

113 

106 

95 

77

1(10

Jan. 14.

Velocity.

0.96 

1.12 

1.23 

1.27 

1.27 

1.25 

1.20 

1.12 

1.04 

.92

1.14

Per cent 

of mean.

84 

98 

108 

112 

112 

110 

105 

99 

91 

81

100

Ve

locit

0.9

1.3

1.5

1.5

1.5

1.5

1.4

1.2

1.0

.7

1.2

" The lower surface of the ice is zero de
58 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. 76. 

TABLE XXIV. Velocities in vertical sections under ice on CatsTcill Creek.®

Total depth.-- 

Thickness of ice . _ .

Depth of water. . . .

^

Feb. 27.

9(1

4.50.

4.1.

. 7.

3.4.

Depth.

Feet.

0.4

.9

1.4

1.9

2.4

3.9

Velocity.

Ft. per 

sec.

1.37

1.57

1.57

1.49

1.16

1.0

Feb. 27.

23

4.96.

4.7.

.5.

4.2.

Depth.

Feet.

0.3

.7

1.2

1.7

o *>

2. 7

3.2

3.7

Velocity.

Ft. per 

sec.

1.50

1.94

1.96

1.89

1.79

1.62

1.37

1.07

Feb. 27.

30.

4.60.

4.5.

1.

3.5.

Depth.

Feet.

0.3

.5

1.0

1.5

2. CT

2.5

3.0

Velocity.

Ft. per 

sec.

1.43

1.84

2

2.03

1.91

1.74

1.55

Feb. 27.

40

4 70

5.8.

1.2.

4.6.

Depth.

Feet.

0.3

.7

1.1

1.0

3.1

3.6

3.1

3.6

4.1

Velocity.

Ft. per 

sec.

2. Si

2.41

2.44

2.47

2.44

2.38

2.31

2.14

1.89

Feb. 27.

60.

4 80

4.7.

1.5.

3.2.

Depth.

Feet.

0.3

.7

1.2

1.7

2.3

2.7

Velocity.

Ft. per 

sec.

1.55

1.77

1.77

1.61

1.35

1.02

« Bed of stream rock ledge from 0 to 55, with gravel and silt over remainder of bed.

TABLE XXV. Velocities at regular intervals in vertical sections on CatsTsill Creels 

under ice, deduced from data in Table XXIV,

[Velocities in feet per second.]

Depth in feet.

0.05................

.15..... ...........

25

.35.. ..............

.45. ._____. ____.._.

.55.. .___.... ...... 

.65....-....".......

. 75...... ........ .

.85.-.. .-

. 95-._. ........ ....

Mean ------ ..

Feb. 27.

Velocity.

1.24 

1.42 

1.55 

1.60 

1.56 

1.48 

1.34 

1.19 

1.01 

.81

1.33

Per 

cent of 

mean.

94 

108 

117 

121 

118 

113 

102 

90 

77 

61

100

Feb. 27.

Velocity.

1.45 

1.82 

1.95 

1.91 

1.86 

1.75 

' 1.60 

1.43 

1.19 

.85

1.58

Per 

cent of 

mean.

92 

115 

133 

121 

118 

111 

101 

90 

75 

54

100

Feb. 27.

Velocity.

1.21 

1.85 

1.98 

2.04 

2.03 

1.95 

1.85 

1.72 

1.65 

1.32

1.75

Per 

cent of 

mean.

69 

106 

113 

117 

116 

111 

106 

98 

89 

75

100

Feb. 27.

Velocity.

2.30 

2.42 

2.46 

2.47 

2.44 

2.40 

2.32 

2.20 

2.04 

1.75

2.28

Per 

cent of 

mean.

101 

106 

108 

108 

107 

105 

103 

97 

89 

77

100

Feb. 27.

Velocity.

1.38 

1.68 

1.76 

1.78 

1.71 

1.58 

1.43 

1.32 

1.01 

.75

1.43

Per 

cent of 

mean.

97 

117 

123 

124 

120 

111 

100 

85 

70 

54

100

The data contained in Tables XIX and XX have been rearranged 

and combined in Table XXVI. The mean of the 26 vertical velocity 

curves taken on the Wallkill is shown in the column headed " Mean." 

The 26 curves are then separated according to the depth of water 

under ice at the point whence the observations were taken. In two 

observations the depth of water was less than 5 feet; in thirteen it 

was from 5 to 10 feet, and in 11 it was from 10 to 20 feet.
PRESSEY.] FLOW OF EIVEES UNDEE IOE. 59

To bring out graphically the form of the vertical velocity curve 

under ice the data in Table XXVI have been plotted in fig'. 5, where 

the solid line represents the mean of the 26 vertical velocity curves 

taken in the Walikill. It will be noted that a decided drag occurs 

at the surface as well as at the bottom of this mean curve; that 

the maximum velocity occurs at a point about 0.35 of the depth, 

and that the mean velocity in the vertical occurs at about 0.13 and 

0.73 of the depth. There will, in general, always be two points of 

mean velocity in vertical velocity curves taken under ice.

The results shown in the three last columns in Table XXYI are also 

plotted in fig. 5; and show the effect of the variation in depth upon 

the form of the curve. It will be seen that the curves drag more at 

shallow depths, the curve for depths under 5 feet being more concave 

than the others, the curve representing the measurements when the 

water was from 5 to 10 feet in depth being next most concave, while 

the curve representing the deepest measurement is flattest. This 

seems reasonable, and would probably hold true in all rivers.

It is frequently desirable to measure the flow of the river when 

frozen over. This can best be done by taking a large number of 

point measurements, as represented in fig. 4, but this is a slow process, 

so that it is important to know at what point the measurement of 

velocity can be made which will represent the mean velocity in the 

vertical section.

It will be seen from the four curves in fig. 5 that measurements made 

at 0.13 and 0.73 of the total depth measured from the bottom of the ice 

will represent in general the mean velocity in a vertical on a stream 

with the same general character as the Wallkill. The variation, however, between the curves representing different depths is greater at 

these two points than at points six hundredths and two-thirds of the 

depth. At these two points the curves almost coincide. The variation between the various curves was less in fact within limits only 

one-half as great at two-thirds depth as at six-hundredths depth. 

This shows that in these curves the limit of error is least when 

measurements are made at two-thirds depth and a coefficient is applied 

to determine the mean velocity. The mean curve shows a velocity of 

105 per cent of the mean at two-thirds depth, so that it would appear 

that the most accurate method of determining the velocity under 

ice by observation at one point in the vertical would be to hold the 

meter at two-thirds depth and apply a coefficient of 0.95 to the 

observed velocity at that point. This would give a better result than 

measuring directly the velocity at 0.13 or 0.73 of the depth. In 

Table XXVII is shown the means of all the curves in the Esopus, 

Rondout, and Wallkill. These have been plotted in fig. 6. The 

variation of these three curves is not large, showing that the curve as
FLOW OF RIVERS NEAR NEW YORK CtTY. [NO. 76.

plotted represents fairly well the typical velocity curve of rivers of 

this character under ice cover. In Table XXVIII the results shown 

in all the preceding tables, for ice cover, including Wallkill, Esopns, 

Rondout, and Catskill, have been combined according to depth of

Depths in 

decimal 

parts of 

total. I

.10

.30

.80

.40

.60

.90

1.00

60

 - Mea

Me<. ?/? of~2t ?c genera 

pfh/ 

 Meanof~/3c(.'n/es,depth befv

n of2c arises, c

and /O 

 Mean of//a/rises, cf

/curi/e 

fhanS 

 een £'

ore /O

!l

70 80 90 100 110 

Velocity in terms of mean velocity = 100.

130 130

PIG. 5. Mean vertical velocity curves on Wallkill River, with ice cover, showing the effect 

upon the curve of variation in depth of water.

NOTE. The solid line is the mean of 26 vertical velocity curves at all depths; the dot-dash line 

the mean of two vertical velocity curves at depths less than 5 feet; the dotted line the mean of 

13 vertical velocity curves at depths between 5 and 10 feet, and the dash-two-dot lines the mean 

of 11 vertical velocity curves at depths greater than 10 feet.

water under the ice, and have been plotted in fig. 7, together with the 

mean of all 47 curves. The form of these curves does not differ 

materially from those for the Wallkill, plotted in fig. 5. The point 

at which these curves fall closest together is, however, somewhat 

higher, at 0.6 depth. To a single measurement made at 0.6 depth a
PBESSEY.] FLOW OF BIVEKS UNDEK ICE. 61

coefficient of 0.92 should be applied to obtain the mean velocity in the 

vertical section, while the coefficient 0.95 should be applied to a single 

measurement made at two-thirds depth, as in the case of the Wallkill, shown in fig. 5.

Depths in

decimal

mrts of

total,

.10

.20

.30

.40

.50

.60

.70

.80

.90

LOO

60

-Maf/M//

-Esopus

- fton&out

^x

\

^

\

60 TO 80 90 100 

Velocity in terms of mean velocity = 100

110 120 130

FIG. 6. Mean vertical velocity curves on Esopus and Rondont creeks and Wallkill Eiver, 

tinder ice cover, showing the comparatively slight variation in vertical velocity curves of rivers 

of this character.

NOTE. The solid, line shows the mean vertical velocity curve on the Wallkill and Rondont 

with the ice broken and tilted, and shows the decided drag caused by the increased friction at 

the surface.

There are many engineers who prefer to measure the velocity at 

mid-depth, and apply a coefficient to obtain the mean velocity in the 

vertical section. The observations recorded in Table XXVII show 

-that the proper coefficient to apply is 0.88. Observations upon the. 

flow of water tinder ice cover on the Upper Mississippi were made by
62 FLOW OF KIVERS NEAK NEW YOKK CITY. [NO. 76.

A. O. Powell, assistant engineer, under the direction of Col. Chas. J. 

Alien, Corps of Engineers, II. S. Army, in 1882 and 1890, and the pubDepths in 

decimal 

parts of 

total.

.10 

.30 

.30 

.40 

.50 

.60 

.70 

.80 

.90

M6c A if

 Mes

/r/Gdn

 Mean

s' 

''.-*

7/7, gene/ 

n ofci/n 

ofcun/e^ 

ofcun/e^

X

.x^ ^.^

"*S

-a/ curyt 

/es, c/epi 

s, depth t 

5, depfhb

/'

^

^>

"^

o

V? /ess /// 

ef weer? i 

efween /(.

/

/, 

/// ''/

^

\ >

\ 

\

><?/? 5' land/O' 

TertdZO'

1 

/

//

// 

/

i

\

\\ 

\\

'

~^~ 'i '

i\i \ a

I

70 80 90 100 

Velocity in terras of mean = 100.

110 120 130

FIG. 7. Comparison of curves for various depths of water under ice cover with the mean of 

all curves taken under ice.

NOTE. The solid line is the mean curve and represents 47 vertical velocity curves. The dashdot line is the mean of 7 curves with depths of water under ice of less than 5 feet. The dotted line 

is the mean of 29 vertical velocity curves with depths of water under ice ranging from 5 to 10 

feet, and the dash-two-dot line is the mean of 11 vertical velocity curves for a depth of water 

under ice ranging from 10 to 30 feet.

lished results 0 show that this coefficient varied from 0.87380 to 

0.88057. 6

«Ann. Kept. Chief of Engineers, U. S. Army, Part in, 1890.

6 Owing to the inaccuracies in observations of this kind, it does not seem to the author justifiable to carry the coefficient beyond the second place of decimals. The results obtained in 

the streams in New York agree with those in the Mississippi to the second place of decimals.
PBESSEY.] FLOW OF EIVEKS UNDER JOE. 63

TABLE XXVI. Mean vertical velocity curve on WallkiH River and curves separated according to depths of water.

[Velocities given in percentages of mean velocity.]

Number of velocity curves. -- . -. - ---------

Depth below bottom of ice.

0.05 .

.15--.-.--. - .--- - ---.-------- -----

.25

.35 -- - .---- .----- --- -----

45

.55 ..--._- --___ _-__ ______ -.__---- 

.65. .--.-------.---.- ----- --- --- 

.75 .

85 - - -

.95

Mean

36.

Mean.

84.0 

103.0 

112.0 

114.8 

114,0 

110.8 

105.8 

-98.4 

87.5 

69.7

100,0

2. 13. 11.

Depth of water under ice.

Less than 

5 feet. -

81.5 

1W.5 

117.0 

119.0 

117.0 

113.5 

107.5 

96.0 

81.0 

60.0

100. 0

Between 5 

and 10 feet.

83.2 

103.7 

114.0 

116.8 

115.7 

111.8 

105.5 

96.6 

84.5 

68.2

100.0

Between 10 

and 20 feet.

85.5 

101.5 

108.6 

111.5 

111.4 

109.3 

105.9 

100.9 

92.1 

73.3

100.0

TABLE XXVII. Mean vertical velocity curves for Esopus, Rondout, and Wallkill, 

based upon a mean of 100.

Stream . . -------

Depth below bottom of ice.

0.05. .._--_ _-. _ ___ ___ _- __.. ____ ------

. 15 -_ ..._.. - __-_.-_--_- - __-_ -. --.--

.25

.35

.45

.55

.65

.75 . ..

85

.95.. .. . . -. ..- -- -. -.. -..

Mean

Esopus.

8.

Mean.

88.2

104.7

112.9

115.9

114.6

111.8

106.8

97.4

84.6

63.1

100.0

Rondout.

8.

Mean.

85.9

103.1

112.1

115.5

115.2

111.7

105.4

96.8,

85.4

68.9

100.0

Wallkill.

26.

Mean.

84.0

103.0

112.0

114.8

114.0

110.8

105.8

98.4

87.5

69.7

100. 0
64 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. 76.

TABLE XXVIII. Mean velocity curves upon WallkiU,Esopus,Rondout,and CatsMil for various depths,

[Velocities given in percentages of mean velocity.]

Number of velocity curves.

Depth below bottom of ico.

0. C5

.15 

.£5

:-35

.45 

55

.65

.r>

.35 

95

7. j 39. 11.

Depth of water under ice.

Less than 

5 feet.

88.0 

109.6 

116.7 

118.4 

 116.1 

111.0 

103.7 

93.2 

80.« 

63.0

100.0

5 to 10 

feet.

85.3 

103.8 

113.3 

116.3 

115.3 

111.8 

105.8 

96.9 

84.8 

66.9

100.0

10 to ;:o

feet.

85.5 

101.5 

108.6 

111.5 

111.4 

109.3 

105.9 

100.9 

93.1 

73.3

100.0

47.

Mean of all 

curves.

85.8 

104.1 

113.6 

115.5 

114.5 

111.1 

105.5 

97.3 

85.8 

67.8

100.0

FLOW OF RIVERS UNDER ICE, BROKEN AND TILTED

COVER.

A few vertical velocity curves were taken on the Wallkill and Ronclout when the ice on the river was broken and more or less tilted. 

No general law can be determined for such conditions, as the impeding power of the ice varies between wide limits. It is interesting, 

however, to note in a general way the effect of the ice. The drag at 

the surface is greatly increased and the curve is changed considerably 

in form. In Tables XXIX to XXXII will be found the results of the 

measurements, while in Table XXXIII is the summary of these 

results. The mean curve, as shown in Table XXXIII, is plotted in 

fig. 8, together with the mean curves when the ice covering was 

smooth. It will be seen from this diagram that the point of maximum 

velocity is 0.55 of the depth, much lower than with smooth ice; that 

the surface velocity is much less, and that the bottom velocity is 

greater. This curve would without doubt vary greatly at different 

times, depending upon the condition of the ice, so that measurement 

at any point for the determination of the mean velocity would not 

be advisable. Point measurements at frequent intervals would be 

necessary in order to obtain reliable results. It is not considered 

that the results show any decided law of relation between velocities 

at various depths, but the general form of the curve is characteristic 

in conditions similar to those under which these were taken.
PBES8EY.] FLOW OF RIVEKS UNDER ICE. 65

TABLE XXIX. Velocities in vertical section on Wallkill River under ice broken

and tilted.

Point of measureTotal depth .......

Thickness of ice. . .

Depth of water. . .

Dec. 19.

115. 

13.70. 

18.0. 

4.0.

140.

Depth.

Feet.

0.5

1.5

3.5

5.5

T.5

9.5

11.5 

13.5

Velocity.

Ft. per 

sec.

0.30

1.27

2.33

2.71

2.99

2.94

2.64 

1.94

Dec. 19.

95. 

13.70. 

16.0*. 

O.Oi.

16.0.

Depth.

Feet.

1.5

3.5

5.5

7.5

9.5

11.5

13.5 

15.5

Velocity

Ft. petsec.

2.73

3.30

3.48

3.84

4.12

3.93

3.60 

2.61

Dec. 19.

85. 

13.70. 

15. 6i. 

O.Oi.

15.6.

Depth.

Feet.

1.1

3.1

5.1

7.1

9.1

11.1

13.1 

15.1

Velocity.

Ft. per 

sec.

2.53

3.08

3.48

3.91

3.95

3.86

3.50 

2.64

Dec. 19.

75. 

13.70. 

14.5. 

1.0.

' 13.5.

Depth.

Feet.

1.0

3.0

5.0

7.0

9.0

11.0

13.0

Velocity.

Ft. per 

sec.

1.52

2.50

2.94

3.03

3.13

2.88

2.45

Jan. 23.

30. 

17.33. 

14.4. 

1.4.

13.0.

Depth.

Feet.

1.0

2.5

4.5

6.5

8.5

10.5

12.5

Velocity.

Ft. per 

sec.

1.72

1.96

2.26

2.56

2.64

2.24

1.67

TABLE XXX. Velocities at regular intervals in vertical section on Wallkill River 

under ice broken and tilted, deduced from Table XXIX.

Depth in parts 

of total.

0.05................

.15...............

. 25.. ........... ...

. 35. ............. ..

.45.. .......... ....

.55.-....-.....-..

.65.. .......... ....

.75- -- 

.85 

.95.. ...... ....

Dec. 19.

Velocity in 

feet 

per 

second.

.1.10 

1.94 

2.41 

2.70 

2.90 

3.00 

2.94 

2.80 

2.55 

2.05

2.44

Per

cent of 

mean.

45 

80 

99 

111 

119 

123 

130 

115 

104 

84

100

Dec. 19.

Velocity in 

feet 

per 

second.

3.35 

3.00 

3.35 

3.65 

3.90 

4.10 

4.07 

3.88 

3.60 

2.85

3.48

Peicent of 

mean.

68 

86 

97 

105 

112 

118 

117 

112 

103 

82

100

Dec. 19.

Velocity in 

feet 

per 

second.

2.40 

2.95 

3.33 

3.62 

3.86 

-3.95 

3.90 

3.76 

3.42 

2.80

3.40

Peicent of 

mean.

71 

87 

98 

106 

113 

116 

115 

111 

101 

82

100

Dec. 19.

Velocity in 

feet 

per 

second.

1.40 

1.94 

2.60 

2.87 

3,04 

3.11 

3.'08 

2.98 

2.78 

2.50

2.63

Per 

cent of 

mean.

54

74 

99 

109 

115 

118 

117 

113 

106 

95

100

Jan. 23.

Velocity in 

feet 

per 

second.

1.68

1.88 

3.07 

2.26 

2.45 

2.62 

2.62 

2.44 

2.15 

1.80

2.20

Per 

cent of 

mean.

77 

86 

94 

103 

111 

119 

119 

111 

98 

82

100

IKR 76 03
66 FLOW OF EIVEBS NEAR NEW YORK CITY. [NO, 76.

TABLE XXXI. Velocities in vertical sections on Rondout Creek at Rosendale 

under ice broken and tilted.

Point of measurement.

Total depth ............

Dec. 6. 

50. 

6.80. 

5.6. 

0.2. 

5.4.

Depth.

0.3 

1.3

. 2.8 

3.8 

4.9

Velocity in 

feet per 

second.

0.21 

.54 

.55 

.57 

.36

Jan. 14. 

40. 

7.00. 

4.8. 

0.8. 

4.0.

Depth.

0.5 

1.5 

2.5 

3.5

Velocity in 

feet per 

second.

0.35 

.75 

.97

.85

Jan. 14. 

50. 

7.00. 

6.4. 

0.4. 

6.0.

Depth.

0.5 

1.5 

2.5 

3.5 

4.5 

5.5

Velocity in 

feet per 

second.

0.72 

.82 

.90 

.90 

.87 

.73

Jan. 14. 

60. 

7.00. 

6.4. 

0.4. 

6.0.

Depth.

0.5 

1.5 

2.5 

3.5 

4.5 

5.5

Velocity in 

feet per 

second.

0.55 

.87 

1.17 

1.15 

1.10 

.86

TABLE XXXII. Velocities at regular intervals in vertical section on Rondout 

Creek under ice broken and tilted, deduced from Table XXXI.

Velocity in 

feet per 

second.

0.25

.46

.54

.57

.57

.56

55

50

.43

.25

.468

Per cent 

of mean.

53

99

115

132

122

120

117

107

92

53

100

Velocity in 

feet peisecond.

0.24

.40

.55

.70

.85

.95

.97

.95

.88

.51

.70

Per cent 

of mean.

34

57

79

100

121

136

139

135

126

73

100

Velocity in 

feet per 

second.

0.67

.76

.82

.88

'.90

.91

.90

.88

.82

.69

.823

Per cent 

of mean.

81

92

100

107

110

111

109

107

100.

83

100

Velocity in 

feet per 

second.

0.48

.68

.87

1.06

1.19

1.19

1.14

1.06

.96

78

.941

Per cent 

of mean.

51

72

93

112

127

126

121

113

102

83

100
PBESSEY.] QUALITY OF WATER. 67

TABLE XXXIII. Summary of curves on WallMll and Rondout, under ice broken

and tilted.

Depth of water below bottom of ice.

0.05-.-----..-------.---...----.--..- ---..--_. --.-- 

.15.. ............... ............ _-..._._..___._........._____.__..

.^. ..................... .........................................

.35...............................................................

.4&........ ..................... ..................................

.55. ...............................................................

.65................................................................

.115................................................................

.85........................... ................................. ...

.95................................................................

Wallkill.

5.

13 to 16 ft. 

River bed: 

Silt.

63.0

82.6

97.4

106.8

114.0

118.8

117.6

112.4

108.4

85.0

100.0

Eondout.

4.

4 to 6 ft. 

River bed: 

Bowlders 

and gravel.

54.8

80.0

96.8

110.2

120.0

123.2

121.5

115.5

105.0

T3.0

100.0

9.

Mean.

59.3

81.4

97.1

108.3

116. 1

120.8

119.3

113.8

103.6

79. 1

100.0

QTTALITY OF RIVER WATER.

A study of the turbidity, color, alkalinity, and hardness of these 

streams has been made in conjunction with the discharge measurements. It is thought that the information derived from such determinations will be of value to engineers investigating the future supply 

of New York City.

TURBIDITY AND COLOR.

Water in its ideal condition is perfectly clear and limpid, and has 

a slightly blue color. Filtered water, distilled water, and many 

spring waters approach closely to the ideal water. Most river waters 

are, however, either colored by contact with peat, muck, or decaying 

vegetation, or are turbid by reason of mud or silt carried in suspension. Muddy waters are often spoken of as colored waters, and in a 

sense this is correct where the mud consists of clays or other materials having distinct colors, but for convenience of classification it is 

better to refer to such waters as turbid waters, and to limit the term 

'' colored waters" to those containing in solution vegetable matters 

which color them.

It has been observed that highly colored waters are usually free 

from turbidity, and vice versa, this being due to the fact that colored 

waters usually flow from drainage areas underlain by hard rocks not 

easily disintegrated, or from regions where the soils are firm or sandy, 

and especially from swamps. On such areas there is but little material that would be washed from the river banks and held in suspension, while the coloring material is present in the greatest abundance. 

In many parts of the United States shales or other soft materials
68 FLOW OF RIVERS NEAR NEW YORK CITY. [NO.76.

form the underlying beds. These readily disintegrate and form clay 

soils that are readily washed by hard rains. Waters from such areas 

are usually turbid and very highly colored.

Turbidity and color are principally important in their effect upon 

the appearance of water, whereas the other impurities discussed in 

this paper have absolutely no effect upon the appearance, and can be 

found only by their chemical action.

TURBIDITY.

The turbidity of water is a subject of great importance to the sanitary engineer. In questions of water supply, turbidity is often the 

important feature in the selection of a source of town supply; the 

number of days upon which the turbidity is ,above a certain fixed 

standard is also important, in that it may determine the size of reservoir required to store clear water sufficient to tide over the time of 

greatest turbidity, or for the sedimentation of suspended matters in 

the reservoir water. The importance of this subject varies with the 

part of the country studied, the waters in the New England States 

and New York being comparatively clear, while in the Southern 

Atlantic States and in the Ohio and Mississippi valleys high turbidities are the rule.

In the Northeast the terms "very slight, "slight," "distinct," and 

'' decided " have been used by analysts to express the amount of suspended matter present. These degrees of turbidity have been estimated by the appearance of the sample to the eye when viewed toward 

the light. As the importance of these analyses has been more appreciated, particularly in connection with the purification of waters and 

the extended studies upon waters of high turbidity, it has been found 

that a more definite scale was necessary in order that, proper comparisons of waters from various sources might be made.

In the filtration of water the engineer desires to know the amount 

of coagulant necessary to properly clarify the water, and it has been 

found that the turbidity gives a reliable index of the quantity of 

coagulant required. The object of the'more recent studies has been, 

therefore, to express it numerically on some scale, referred to some 

standard, which can be easily reproduced and will be permanent.

There has been considerable difference of opinion as to the proper 

standard for turbidity comparisons, and some confusion has resulted. 

It is important that any standard selected should be applicable to 

both field and laboratory practice, and that observations made by 

different methods should be readily comparable.

The United States Geological Survey has had occasion, from time 

to time, to make observations of turbidity of rivers of which discharge 

measurements were made. Realizing the importance of a uniform 

standard for turbidity, the Survey has cooperated with Mr. Alien
PRESSEY.] TURBIDITY. 69

Hazen and Mr. George C. Whipple in order that such a standard 

might be adopted. Mr. Hazen and Mr. Whipple have made joint 

investigations and studies, and have recommended the standard given 

below. This will be used in the future by the Survey, and it is hoped 

may be adopted generally throughout the United States.

PROPOSED TURBIDITY STANDARD.«

The standard of turbidity shall be a water which contains 100 parts 

of silica per million in such a state of fineness that a bright platinum 

wire 1 millimeter in diameter can just be seen when the center of the 

wire is 100 millimeters below the surface of the water and the eye of 

the observer is 1.2 meters above the wire, the observation being made 

in the middle of the day, in the open air, but not in sunlight, and in 

a vessel so large that the sides do not shut out the light so as to influence the results. The turbidity of such water shall be 100.

The turbidity of waters more turbid than the standard shall be computed as follows: The ratio of the turbidity of the water to 100 shall 

be as the extended volume is to the original volume, when the water 

is diluted with a clear water until the mixture is of standard turbidity.

The turbidities of waters lower than the standard should be computed as follows: The ratio of the turbidity of the water to 100 shall 

be as the ratio of the original volume of water of standard turbidity is 

to the extended volume when such water is diluted with a clear water 

until its turbidity is equal to that of the water under examination.

This standard can be used in both field and laboratory. In the field 

the wire method will be carried out as at present, except for a new 

graduation, while in the laboratory the methods of dilution and comparison now in use for the silicia standard will be used.

METHOD OF APPLICATION TO THE PLATINUM-WIRE PROCESS.

A rod with a platinum wire inserted in it at a fixed point and 

projecting from it at a right angle will be used as at present. The 

graduation shall be as follows: The graduation mark of 100 shall be 

placed on the head at a distance of 100 millimeters from the center of 

the wire. Other graduations will be made, based on the best obtainable data, in such a way that when a water is diluted the readings 

will decrease in the same proportion as the percentage of the original 

water in the mixture. Such a rod, having the graduation shown in 

the table below, shall be known as the United States Geological Survey turbidity rod of 1902. When this rod is immersed in water the 

visibility ftf the projecting platinum wire at the depth from the surface shown in the second column will determine the degree of turbidity, as indicated in the first column.

<* From a letter signed by Messrs. Alien Hazen and George C. Whipple.
70 FLOW OF RIVERS HEAR NEW YORK CITY. 

Graduation of rod.

[NO. 76.

Turbidity.

7

8

9

10

11

12

13

14

15

16

17

18

19

20

22

24

26

28

30

35

40

45

50

55

60

65

Depth of 

wire.

Mm.

1095

971

873

794

729

674

627

587

551

520

493

468

446

426

391

' 361

336

314

296

257

228

205

187

171

158

147

Corresponding value on 

reciprocal 

scale.

0.023

.026 -

.029

.032

.035

.038

.041

.043

.046

.049

.052

.054

.057

.060

.065

.070

.076

.081

.086

' .099

.111

.124

.136

.148

.160

.172

Turbidity.

70

75

80

85

90

95

100

110

120

130

140

150

160

180

200

250

300

350

400

500

600

800

1000

1500

2000

3000

Depth of 

wire.

Mm.

138. 0

130.0

122.0

116.0

110.0

105.0

100.0

93.0

86.0

81.0

76.0

72.0

68.7

62.4

57.4

49.1

43.2

38.8

35.4

30.9

27. 7

23.4

20.9

17.1

14.8

12.1

Corresponding value on 

reciprocal 

scale.

0.184

.196

.208

.219

.230

.242

.254

.273

.295

.314

.334

.35

.37

.41

.44

.52

.59

.65

.72

.82

.92

1.09

1.21

1.49

1.72

2.10

This table is compiled from observations made at Cincinnati, St. 

Louis, New Orleans, Pittsburg, Brooklyn, Philadelphia, and Boston, 

for records of which we are indebted to several observers. The values 

of the turbidities by the reciprocal scale are included in the table as 

a matter of convenience, but they do not form a part of the standard.

This graduation is subject to revision whenever additional data 

shall make it necessary, and revised rods shall be designated by the 

same name, but with the year of revision substituted for 1902. The 

revisions shall have as their basis the one hundred mark, 100 millimeters from the wire.

Near the end of the rod, at a distance of 1.2 meters from the platinum wire, a wire ring shall be placed directly above the wire, through
U. 8. GEOLOGICAL SURVEY WATER-SUPPLY PAPER NO. 76 PL. IX

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12500 

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11500 

11 000 

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10 20 40 60 60 70 80 90 100 110

Turbidity

120 180 140 *«0 160 170 .180 190

DIAGRAM SHOWING RESULTS OF TURBIDITY OBSERVATIONS.
PRBSSEY.] TURBIDITY.

which the observer will look, the object of the ring being to control 

the distance from the wire to the eye.

When the turbidity is greater than 500 the water should be diluted 

before the observation is made. When the turbidity is below 7 this 

method can not be used, and comparison should be made with the 

silica standard properly diluted in bottles or tubes. a

The number obtained by dividing the weight of suspended matter 

in parts per million by the turbidity as obtained above shall be called 

the coefficient of fineness. If greater than unity, it indicates that the 

matter in suspension in the water is coarser than the standard; if less 

than unity, that it is finer than the standard.

This standard is proposed with the idea of combining the best 

features of the platinum-wire and silica methods of measuring turbidities as commonly used, and of avoiding, as far as possible, the 

objections to each.

The wire method is most convenient as a field method. With the 

reciprocal scale, which until now has been used, it is open to the serious objection that the readings are not proportional to the amount of 

turbidity-producing matter in the water.

The silica standard is free from this objection and is more convenient as a laboratory method, but is not well adapted to field use, and 

is open to the objection that it is possible that the value may be 

changed by variations in the fineness of the silica particles composing 

the standard.

The standard now proposed is intended to overcome the abovementioned defect in the platinum-wire method with the reciprocal 

scale, and at the same time to put a control on the value of the silica 

standard. Applying it in one way or the other, it is adapted to both 

field and laboratory use, and the results obtained should check 

substantially.

METHOD OF MAKING OBSERVATIONS.

The method of making the observations by means of the platinum 

wire is as follows: Take a stick of wood about 5 feet long and fiveeighths of an inch square, more or less, and insert a platinum wire at 

a point about 1 inch from the end, so that the wire will be at right 

angles to the stick and project at least 1 inch. The wire should be 

0.04 inch or 1 millimeter in diameter; the stick is then graduated, the 

lines for the various turbidities being at distances from the wire 

shown in the table on page 2.

Observations of turbidity are taken by putting this stick into the 

water under examination as far as the wire can be seen; the turbidity 

is then read from the scale. This is most conveniently accomplished 

by having a second or smaller stick placed in front of the first, the 

end of which is brought to the water line when the wire can just be

_2Described by Whipple and Jackson in Technology Quarterly, Vol. XII, No. 4, December, 1899.
72 FLOW OF EIVEES NEAE NEW YOEK CITY. [NO.76.

seen. Upon removing the two together the position of the smaller 

stick on the scale gives the turbidity.

Observations are to be taken in all cases in open air, as too high 

results are obtained under a roof, even with very good light; and 

they should preferably be taken in the middle of the day and not in 

direct sunlight. In case the sun is shining the observer can stand so 

that his shadow covers the water immediately about the stick and 

wire. The observations are taken with the eye of the observer at the 

ring before mentioned, 1.2 meters from the wire, although some variation in this does not materially influence the result. The wire should 

be kept bright and clean. In case it is lost, a clean bright pin can be 

used until another wire can be obtained. When the surface of the 

water in the stream is agitated by currents, waves, etc., or in case the 

depth is not sufficient to give the required immersion, or if for any 

reason observations can not be well taken from the bank, a pail or 

tub may be filled with water and the turbidity observations taken in 

it. In many cases this procedure is preferable to measurement in a 

stream, but the observation must be taken immediately upon filling 

the vessel. The diameter of the vessel should be equal to at least 

twice the depth at which the wire is immersed, as otherwise the results 

of the reading will be affected.

When the turbidity of the water is above 500, that is, in case the 

wire can be seen through less than 1 inch of water, the results obtained 

by direct measurement are not accurate. Such water should be diluted 

by 1, 2, or 4 volumes of clear water in the pail or tub, and thoroughly 

mixed.

The turbidity is taken as above described, and multiplied by the 

ratio that the total volume of water bears to the water in the mixture. 

Clear water can be obtained from a well or any other source obviously 

clear, or nearly so.

The statement of turbidity in such cases should contain memoranda 

that the observations were taken in this way, and should give the 

amount of dilution.

If waters have a turbidity less than 7 direct reading can not be used, 

and indirect methods onust be resorted to.

The "wire method " has been described first in this paper, as it is 

best suited to field work. Besides this method, there are two others 

that have commended themselves to practical use. First, the use of 

standards of comparison; second, the diaphanometer. a

In the determinations of turbidity of waters in rivers considered in 

this paper, the turbidities were in general too low for accurate measurements by the wire method, and as the samples had to be shipped to 

the laboratory for other determinations, the turbidity was found by 

comparison with standards. These standards were made up from diaa These are botk laboratory methods, and have been described by Mr. G-eorge-C. Whipple and 

Daniel D. Jackson, in the Technology Quarterly, Vol. XII, No. 4, December, 1809.
U. S. GEOLOGICAL SURVEY WATER-SUPPLY PAPER NO. 76 PL. X

TUBES AND DISKS FOR MEASURING IN THE FIELD THE COLOR OF RIVER WATER.
PRESSEY.] COLOR. 73

tomaceous earth thoroughly washed and ignited to remove the organic 

matter. The earth is then washed in hydrochloric acid and rinsed 

with water, after which it is pulverized. One-half grain is added to 

500 c. c. of distilled water and thoroughly agitated. This stock mixture contains 1 grain of pure silica per liter, or 1,000 parts per 1,000,000, 

and when well shaken will always give the same turbidity, which is 

called a standard 1,000. For waters of. low turbidities, like those 

found in New York State, standards are made by diluting the stock 

mixture with distilled water in measured proportions and comparing 

the collected samples with the various standards in gallon bottles, 

while with higher turbidities smaller quantities of the standards are 

placed in 100 c. c. Nessler tubes, with which the samples in like tubes 

are compared. This is a laboratory method, and is more precise than 

the wire method of making determination of turbidity, but requires 

that samples be collected and shipped to the laboratory.

In order that some idea of the meaning of the various standards may 

be obtained, the following table is inserted:

Table showing meaning of various numbers on silica scale.

Silica standard.

0.._. .

1-3---.. ..--._..-.--------_-___.-_.... ... ... ......... .....

3-5................................... . ..............

5-30..... ............... .. .. ... ....

Above SO.--...---. -----..-._-_.... ...._ .........---..-....-

Destriptive term.

None.

Very slight.

Slight.

Distinct.

Decided.

COLOR.

The platinum-cobalt method of measuring color, as devised by Alien 

Hazen, is generally considered the standard.

A standard solution which has a color of 500 shall be made by dissolving 1.246 grains potassium-platinic chloride 05 (PtCl4 ,2KCl), containing 0.5 gram platinum, and 1 gram of crystallized cobalt chloride 

(CoCl3 ,6H2O), containing 0.25 gram of cobalt in water, with 100 

cubic centimeters concentrated hydrochloric acid, and making up to 

1 liter with distilled water. By diluting this solution standards shall 

be prepared having values of 0, 5, 10, 15, 20, 25, 30, 35, 40, 50, 60, and 

70. The numbers correspond to the metallic platinum in the solutions in parts per million. These shall be kept in 100-cubic-centimeter 

Nessler jars of such diameter that the liquid shall have a depth 

between 20 and 25 centimeters and shall be protected from dust. The

aPota&sium-platinous chloride is a salt that is often, substituted by dealers in place of the 

potassiurxi-platmic chloride. It is sometimes incorrectly labeled. The platinous salt has a reddish color while the platinio salt has a yellow coloi.
74 FLOW OF EIVEES NEAE NEW YORK CITY. [NO,76.

color of a sample shall be observed by filling a similar tube with water 

and comparing it with the standards. The observation shall be made 

by looking vertically downward through the tubes upon a white surface placed at such an angle that light is reflected upward through 

the column of liquid. The reading shall be recorded to the nearest 

unit. Waters that have a color darker than 70 shall be diluted before 

making the comparison, in order that no difficulties may be encountered in matching the hues. Water containing matter in suspension 

shall be filtered until no visible turbidity remains. If the suspended 

matter is coarse, filter paper may be used for this purpose; if the suspended matter is fine, the use of the Berkfeld filter is'recommended, 

but it must be thoroughly washed each time before using. The use 

of a Pasteur filter is to be avoided, as it exerts a decolorizing action.

The determinations of color upon the streams considered in this 

paper, and given on the following pages, were made by the above 

laboratory method. For the sake of completeness, however, the field 

method of making determinations of color will be described.

It is impracticable to carry the standard tubes above described into 

the field for observations, and yet field observations are of great convenience and value to the sanitary engineer, and in general to the 

investigations of the United States Geological Survey.

Standard disks of colored glass have been prepared by Mr. Alien 

Hazen, in cooperation with the Survey, as standards for measuring 

color of water in the field (PI. X). These disks have been rated by 

Mr. George C. Whipple to correspond with the platinum-cobalt standard. The color is measured by balancing the color of the water in a 

metallic tube with glass ends against the colors of glass disks of 

known value. The number on each disk represents the corresponding color of a water. This is not a new standard, but a new application of an old standard. The glass disks are rated to correspond 

with the platinum-cobalt color standard. The process bears the same 

relation to the usual laboratory process that an aneroid barometer 

bears to a mercurial barometer. The metallic tubes and glass standards are more portable and better adapted to field use than the Nessler 

tubes and color solutions previously used.

Color standards. The standards are disks of amber-colored glass, 

mounted with aluminum. Each disk carries two numbers. One 

number is over 100, and is a serial number for the purpose of identification. The other number is less than 100, and shows the color 

value of the disks; that is to say, the color of each disk is equal to 

the color of a solution of the designated number of parts per million 

of platinum with the required amount of cobalt to match the hue 

when seen in a depth of 200 millimeters.

Each apparatus has a series of glass disks of varying values, so 

that waters within a reasonable range can be matched by them. 

When a water comes between two disks its value can be estimated
PKHSSEY.] COLOE. 75

between them by judgment. Two or more disks can be used, one 

behind the other, in which case their combined value is the sum of 

the individual values. By combining the disks of a series in different 

ways a considerable number of values can be produced, allowing the 

closer matching of many waters.

Filling the tubes. The tube, having an aluminum stopper, is to be 

filled with water, the color of which is to be determined. Rinse the 

tube once or twice by filling and emptying it. The second tube, having 

the clips to hold the glass" disks, is made much like the one holding 

the water to facilitate comparison. Theoretically this tube should be 

filled with distilled water. Practically it makes very little difference 

whether it is filled with distilled water or empty. Use distilled water 

when it is convenient to do so, and when distilled water of unquestionable quality is at hand; otherwise wipe the inside of the tube 

dry to prevent fogging of the glass ends, and proceed with the tube 

empty.

Holding the tubes. Hold the tubes at such a distance from the eye 

that the sides of the tubes just can not be seen. This occurs when the 

near end of the tube is 8 or 9 inches from the eye. Hold the tubes at 

such an angle that both can be seen at once with one eye. Good 

results can not be obtained in any other way. Let the tubes change 

places once or twice, as sometimes the light on the right and left is 

not quite equal.

Background. There should be a clear white background with a 

strong illumination. The best results can not be obtained with either 

too little or too much light. In a gray day look at the sky near the 

horizon and away from the sun. In a bright day look at a piece of 

white paper or tile, upon which a strong light falls. The white surface may be vertical and the tubes held horizontally, or the tubes may 

be held at an angle directed downward toward a horizontal surface, 

as may be most convenient. Good results can not be obtained by 

artificial light.

Turbid water. The colors of very turbid waters can not be measured in this way. Slight turbidities do not interfere seriously with 

the results. Waters too turbid for direct observations should be filtered through thick filter paper before being tested, and in case the 

turbid matter is fine and in large amount even this method may fail. 

The turbidity of water should be taken as far as possible in connection 

with color observations, except in cases where it is obvious from 

inspection that there is practically no turbidity.

Highly colored waters. Some waters will be found having a higher 

color than can be matched by the standards. In general, waters with 

colors above 100 should not be matched in 200-millimeter tubes, and the 

results with waters having colors below 80 will be considerably more 

accurate than with more highly colored ones. Two procedures are 

possible with waters having higher colors namely, to dilute with dis-
T6 FLOW OF RIVERS NEAR NEW YORK CITY. [NO.76.

tilled water before measuring the color or to use shorter tubes. The 

latter procedure is the more convenient, but both are equally accurate. To measure the color with short tubes, put the highly colored 

water in a tube of one-half the usual length and match as usual. It 

is not necessary to have a short standard holder. The 200-millimeter 

tube can be used. After the water is matched the result is multiplied 

by 2. In case the color is too high to be read in a 100-milliineter tube 

it can be put in a 50-millimeter^tube, and the result multiplied by 4. 

When dilution is used the highly colored water is mixed with one or 

more volumes of distilled water, the color matched, and the result 

multiplied by a corresponding factor. The tube itself can be used 

for measuring the colored water and the distilled water, and the mixing can be clone in a tumbler or any convenient clean vessel.

Cleaning the tubes. The tubes should always be kept clean and 

the glass ends protected. All the ends are removable for the purpose 

of cleaning, and should not be screwed on too tightly. They should 

be water-tight when only screwed up loosely, and if screwed on hard 

they may stick so as to come off with difficulty.

ALKALINITY.

The alkalinity of water is practically a measure of the carbonates 

and bicarbonates present. The determination is made as follows: 

Put 100 c. c. of the sample into a 6-inch porcelain evaporating dish. 

Add two or three drops of a 0.1 per cent aqueous solution of methylorange. If the water is alkaline, this will impart to it a faint yellowish brown color. Then from a burette graduated in tenths of a cubic 

centimeter run in a fiftieth-normal solution of sulphuric acid until the 

color of the water changes to a faint pink. The acid must be added 

in small portions (only one drop at a time as the end point is reached) 

and the water stirred with a glass rod after each addition. The number of cubic centimeters of fiftieth-normal acid required, when multiplied by ten, gives the alkalinity of the water expressed in equivalent 

parts per million of calcium carbonate. That is, if 1.8 c. c. is required 

to cause the color of the indicator to change from brown to red, then 

the alkalinity of the water is 18 parts per million. Inasmuch as it 

is necessary to add a certain amount of fiftieth-normal acid to 100 c. c. 

of water which has no alkalinity in order to produce the typical color 

change, the reading obtained must be corrected for this amount. This 

correction for the indicator varies with different individuals, but it 

seldom exceeds 0.3 c. c.

Other indicators, such as lacmoid or erythrosine, may be used in 

place of methyl-orange, and in certain instances their use is to be preferred, but for general field work methyl-orange is most convenient.

PERMANENT HARDNESS.

The Clark's soap method has been used in the examinations of river 

waters given in the following tables. This method gives reliable
U. 8. GEOLOGICAL SURVEY

14900

WATER-SUPPLY PAPER NO. 7« PL. XII

Alkalinity 

DIAGRAM SHOWING RESULTS OF ALKALINITY OBSERVATIONS.
QUALITY OF RIVER WATER. 77

results for waters as soft as those under consideration, but for the 

hard waters of the Central States Hehner's acid method will perhaps 

give more reliable and uniform results.

Results of determinations of hardness obtained by various observers are frequently very discrepant, and it is not uncommon to have 

results reported by chemists which are worthless on account of faulty 

methods. It is hoped that the determinations of hardness may be made 

upon a more uniform basis throughout the country, so that the results 

may be comparable.

In the following tables are given the results of the observations upon 

turbidity, color, alkalinity, and hardness, together with the discharge 

of Esopus, Rondout, Wallkill, Catskill, Fishkill, Tenmile, and Housatonic:

Turbidity color, alkalinity, and hardness of streams.

CATSKILL CREEK.

Date.

1901. 

Aug. 19 . _ . . ____________

Aug. 27 ________________

Sept. 2_-_._ .___.___ __

Sept. 8_... ....... . _

Sept. 23 ___________

Oct.4. _________________

Oct. 10. ......... .......

Oct. 22_. _______________

Nov. 8-________________

Nov. 19 ._..___________.

Dec. 9__. _____________ _

1902.

Feb. ST..... ............

Apr. 10 ----------_---.-

May 10________. ________

June 3 .-.___.____ __._.

June 24 _____________ .

July9___. ....-.._.._._.

July 23 ________________

Aug. Z .................

Aug. 18... __-..._.. ....

Aug. 27 ________________

 Sept. 5. - ..-..... .

Gage 

height.

a 2 62

«2.95

«3.00

«2.90

2.73

2.70

2.65

2 82

2.70

2.75

3.30

3.50

4.90

6.70

3.47

2 82

2.70

3.40

6.11

5.36

3.49

2.74

2.79

Color.

6

11

9

2

4

1

6

1

3

2

9

22

22

4

6

9

9

35

33

12

11

6

Turbidity.

1

2

3

2

2

1

3

1

1

11

25

6

' 1

3

9

25

12

1

4

4

Alkalinity58.0

48.0

53.0

55.0

54.0

51.0

53.0

50.0

49.0

50.0

38.0

38.0

25.0

22 0

36.0

42 0

47.0

45.0

35.0

42.0

50.0

56.0

56.0

Hardness.

53.0

50.0

50.0

44.5

42.0

26.0

24.0

43 0

50.0

51.5

47.0

44.5

49.0

50.5

52.0

56.0

Discharge in 

second-feet.

28

77

89

66

39

36

31

51

36

43

110

1/M

400

3,200

133

99

43

113

1,603

1,005

135

394

50

"Taken from gage height record.
78 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. re.

Turbidity, color, alkalinity, and hardness of streams Continued. 

RONDOUT CREEK.

Date.

1901. 

A no- <>fi

Sept.l .................

Sept.3 .................

Sept.4 .................

Sept. 19 __._________...-

Do_. ...............

Oct. 11 -_.___________..-

Oct.8___. ______________

Oct. 15 .................

Oct.23 ________________

Oct.31 _______________

Nov. 13. ...............

]Srov.l6___________.-____

Nov. 19.. ...............

Nov 23

Nov. 36..... ____________

Noy.39______.__. _______

Dec.3_. ________________

Dec.6........ ...-....._

Dec. 10-. .............. _

Dec.ll .................

Dec. 13.... .............

Dec. 15 ...... ...........

Dec. 16..... ............

Dec. 25 .................

Dec. 30--.. .............

1902.

Jan. 14____ _... .......

Jan.18 -._.____.___._..

Jan. 33 ________________

Jan. 28____... .........

Feb. 4_. __.._____..____

Feb. 11................

Feb. U... ........... _

Feb. 27................

«Lil

Gage 

height.

7.15 

7.63 

7.80 

7.13 

6.87 

6.87 

6.50 

6.95 

7.65 

6.70 

6.50 

7.00 

6.60 

6.40 

6.35 

7.30 

6.80 

6.40 

6.80 

9.80 

9.50 

8.50 

16.70 

11.00 

7.25 

13.20

. 7.00 

6.70 

6.70 

10.30 

7.90 

7.70 

9.50 

8.20 

7.85 

10. 45 

cely too low.

Color.

42 

32 

66

68 

30 

30 

26 

40 

26 

28 

24 

21 

26 

31 

23 

32 

31 

23 

21 

32 

38 

34 

80 

48 

13 

32

17 

14 

14 

32 

23 

80 

14 

11 

10 

22

Turbidity.

4 

20 

6

15 

12 

13 

4 

4 

8 

3 

4 

14 

5 

2 

3 

7 

3 

7 

3 

65

( b ) 

19

( b) 

75 

7 

60

5 

4 

3 

3

1 

10 

18 

11 

6

30 

feBottl

Alkalinity.

37.0 

23.0

11.0 

18.0 

18.0 

14.0 

17.0 

22.0 

22.0 

20.0 

24.0 

26.0 

20.0 

30.0 

19.0 

17.0 

31.0 

31.0 

19.0 

19.0 

13.0 

12.0 

13.0 

11.0 

14.0 

10.0

14.0 

20.0 

18.0 

10.0 

12.0 

21.0 

14.5 

19.5 

30.0 

13.0 

B broken.

Hardness.

32.0 

«21.0 

« 19.0 

a 24. 0 

27.0 

26.0 

24.0 

25.0 

23.0 

34.0 

24.5 

23.5 

25.0 

20.0 

17.5 

18.0 

20.0 

26.0 

20.0

24.0 

23.5 

21.0 

12.5 

14.5 

25.5 

21.5 

24,5 

24.5 

15.9

Discharge in 

second-feet.

620

980 

1,126 

603 

430 

430 

185 

481 

1,001 

314 

185 

515 

249 

123 

92 

728 

380 

123 

280 

1,700 

2,650 

1,750 

12, 230 

4,250 

592 

5,574

515 

240 

240 

3,480 

1,212 

675 

2, 650 

900 

742 

2,000
U. 8. GEOLOGICAL SURVEV 

140001 

WATER-SUPPLY PAPER NO. 78 PL. XIH

01

0

f*\ I_LM 11-MLI -L ma | mu

©_-_._ _ Wallkill

a.- .. Catskill 

0 Tenmile 

0 Rondo tit' 

B _x_« *_ Housatonic

bfl co 

LU

05

0 Tisr

K

\

\

O

tski/l 300-

100 110 140 ISO

Hardness*

DIAGRAM SHOWING RESULTS OF HARDNESS OBSERVATIONS.
PRESSEY.] QUALITY OF EIVEE WATER. 79

Turbidity, color, alkalinity, and hardness of streams Continued. 

RONDOUT CREEK Continued.

Date.

1902. 

Mar. 1 .................

Mar. 2 _________________

Mar. 3 _ ... ... ..

Mar. 8 ...... .... __.

Mar. 9 .................

Mar. 9 ---------...-_--.

Mar. 10 ................

Mar. 29 .........._.....

Apr. 8 -_--___--________

Apr. 10 ................

Apr. 34................

Apr. 26 ---___.___._____

Apr. 30 ................

May 26.-......-.-..-...

May 38.. ...... ..-.,-.. .

June 6 . ___________

June 18 ......-........_

June 22 ................

June 28 ................

July 3... ....___.__.____

July 19_. _.__..____-____

July 21........ .........

July 22.. ..._...._....._

July 23.. ... _________

July 26... ............ _.

July 81. ..._............

Aug. 7... ..............

Aug. 18................

Aug. 15. ...............

Aug. SO................

Aug. 21 ................

Aug. 25 . ___ ..-.______

Aug. 37.--....-.-..-.-.

Aug. 30 ..-.-_-.-._...-.

Sect. 5............ .

Gage 

height.

17. 55

14.00

11.75

9.90

12.70

9.50

10.00

11.00

7.65

11.95

6.90

7.10

9.30

6.90

7.10

6.45

6.40

6.50

6.30

7.20

7.55

6.80

6.30

8.65

9.75

8.60

9.85

7.35

7.39

6.80

6.50

6.40

6.35

6.25

6.30

6.35

6.10

Color.

42

40

31

21

30

35

19

23

25

21

32

14

16

25

12

14

14

13

13

13

12

21

31

15

40

35

45

45

30

28

17

1620*

16

11

14

12

11

Turbidity.

145

120

55

30

28

48

50

80

40

15

32

4

35

28

8

21

18

7

10

14

20

24

30

2

95

105

35

45

14

8

2

1

2

2

5

13

5

4

Alkalinity.

14.0

14.5

11.0

9.5

14.0

12.5

14.0

12.5

14.0

13.0

12.0

18.0

15.5

13.5

23.0

23.0

27 0

23.0

28.0

32.0

25.0

20.5

21.5

27.0

21.0

15.0

13.0

15.0

14.0

19.0

18.0

22.0

24.0

25.0

23,0

30.0

26.0

26.0

Hardness.

14.3

13.5

11.9

12.0

16.5

15.0

21.0

19.5

19.0

17.0

14.0

22.0

20.5

19.0

24.5

24.5

28.0

25.0

30.0

32.5

31.2

24.7

22.8

30.5

22.0

19.5

17.0

24.0

24.0

26.0

£3.0

22.5

28.0

27.0

24.5

29.0

27.5

31.0

Discharge in 

second-feet.

13,900

7,900

5,075

3,043

1,084

6,120

2,650

3,150

4, 250

1,000

5,665

447

585

2,470

447

585

156

163

185

75

656

920

380

75

1,885

2,890

1,840

2,991

765

838

380

185

123

92

60

75

92

35
80 FLOW OF EIVEE8 NEAE NEW YOEK CITY. [NO. 76.

Turbidity, color, alkalinity, and hardness of streams Continued. 

RONDOUT CREEK Continued.

Date.

1902.

Sept. 8_____.__ ________

Sept. 11 _______________

Sept. 16 _ _ _ _ _ _ _ _

Sept. 17 _.__._._--__-.__

Gage 

height.

6.20

6.50

6.30

6.20

Color.

11

14

17

Turbidity.-

2

6

3

3

Alkalinity.

28.0

23.0

23.0

23.0

Hardness.

31.0

24.5

26.0

28.0

Discharge in 

second-feet.

50

185

75

50

ESOPUS CREEK.

1901. 

A TIP- ^

Aug. 27---------------

Aug. 29--____..--_.____.

Sept. 4. ...

Sept. 21 ______________ _

Sept. 26. _______________

Oct. 3-___---_-____--_-_

Oct. 8_-___-_-__.__ ...

Oct. 17- - ----_-

Nov. 1 __ __ _ _______

Nov. 14___________.._._

Nov. 18__ ____.._. .

Dec. 4-______--_. _______

Dec. ll.__. ____________

Dec. 19____. __._ _______

Dec. 30. _____---.-___-._

1902.

Jan. 22 _____ ----_

Feb. 7... ...... _..__-...

Feb. 20. -_.___-___._____

Mar. 1 ._ __

Mar. 12 ______________

Apr. 10 _.______. _____

Apr. 23 _-___..______-__

May 14. _ _____ ___ __

May 24____. ____________

June 5 _ _ --.___ _--._

June 16 .-__- - _ _ _ _ _

June 26 ________________

"From Aug. go to Oct

7. 67 

6.02 

5.72 

6.27

4

f*fQ 

. (0

4.55 

5.25 

4.70 

6.30 

4.75 

4.75 

4.45 

5. 30 

Ml. 40 

8.35 

12.10

6.50 

16.00 

6.80 

5.35 

20.40 

9.90 

13.25 

6.94 

5.83 

5.02 

5.03 

4.48 

5.00 

8, hardness i

52 

34 

28 

19 

11 

9 

16 

14 

14 

9 

9 

9 

10 

45 

22 

25

15 

29 

16

8 

- 48 

25 

,23 

16 

12 

8 

14 

10 

18 

lot detent

35

7 

3 

13 

8 

4 

6 

3 

10 

4 

4 

2 

6 

38 

50 

80

15 

180 

20 

5 

180 

125 

35 

21 

10 

4 

17 

5 

18 

lined.

17.5 

22.0

19.0 

23.0 

23.5

18.0 

18.0 

14.0 

15.0 

21.0 

17.0 

16.0 

10.0 

23.5 

11.0

13.0 

10.0 

15.0 

19.0 

11.0 

18.5 

9.0 

13.0 

16.0 

19.0 

20.0 

24.0 

20.0

(«)

15.0 

18.0 

22. 0 

22.0 

20.5 

16.0 

19.0 

17.0

21 0 

15 0 

19.5 

23.5 

16.5 

23.5 

13.5 

15.0 

20.0 

24.0 

22.5 

26.0 

22.0 

spaclrw

1,200 

540 

430 

640 

198 

167 

295 

188 

650 

195 

195 

153 

223 

1,721 

1,470 

3,723

514 

7,600 

628 

231 

12, 600 

2, 843 

5,021 

910 

474 

238 

2,345 

1, 358 

2,312 

rater.
PBESSEY.] QUALITY OF EIVEE WATEE.

Turbidity, color, alkalinity, and hardness of streams Continued. 

ESOPUS CREEK-Continued.

81

Date.

1902. 

July 9, ........ .........

July 16-,-_-_. _._______.

July24.___-__.__. .....

July 30---__-______..--_

A n tr 1 °

Aug. 21 ______._____--._

Sept. 4--___._ .........

Gage 

height.

5.80

5.13

8.11

7.65

6.28

4.94

4.49

Color.

20

10

35

23

21

14

11

Turbidity.

12

10

15

8

8

6

6

Alkalinity.

16.0

18.0

15.0

14.0

24.0

23.0

34.0

Hardness.

27.5

37.5

38.5

34.0

26.5

25.5

31.0

Discharge in 

second-feet.

4,504

2,688

1,348

1,155

550

191

133

WALLKILL RIVER.

1901.

A 11 cr 1 *7

Aug. 20 ______________

Aug. 23 .___ ......... _

A 11 o* O/L

Aug. 28 _-__.-.--- .-.___

Aug. 31 _-.___--______

Sept. 5... --------------

Sept. 19-----____._--_-.

Oct.9.. ...... ...... ....

Oct. 31 1.. ...............

Nov. 9 ........... .....

Nov. 16 ____ --_____ ...

Dec. 11........... __

Dec. 19__-_____, ________

Dec. 30. ________________

1902. 

Jan. 13 ........_......-.

Jan. 23 ________ ........

Feb. 10... __-._--______

Feb. 24__________-____._

Mar. 10 ............. __

Apr. 21________, '_*_____

May 1 ..................

May 31.... .............

June 6 ___.-.__ _______

July 17-. ____---______. _

July 29___. ____________

6.75 

7.2 

6.25 

6.05 

5.85 

5.95 

8.55 

7.30 

6.50 

6.10 

5.94 

6.50 

«11.50 

13.70 

30.20

8.05 

16.40 

7.78 

7.30 

16.40 

7.55 

10.00 

6.33 

6.40 

5.70 

7.49 

<

78 

110 

104 

110 

82 

86 

82 

45 

60 

46 

28 

45 

60 

55 

35

33 

38 

21 

19 

31 

29 

60 

39 

30 

33 

52 

» Baefewat

3 

9 

6 

12 

14 

13 

12 

13 

7 

5 

4 

9 

45 

38 

45

15 

125 

14 

10 

160 

35 

38 

8 

13 

5 

23 

w.

77.0 

48.5 

58.0 

64.0 

62.0 

71.0 

65.0 

59.0 

67,0 

81.0 

92.0 

88.0 

43.0 

37.0 

34.0

74.0 

25.0 

67.0 

89.0 

26.0 

56.0 

44.0 

75.0 

73..0 

82.0 

54.0

93.0 

105. 0 

97.0 

50.0 

42.0 

26.0

83.0 

30.0 

76.0 

97.2 

31.0 

60.0 

46.0 

89.0 

84.0 

90.0 

72.0

565 

794 

321 

232 

165 

196 

1,503 

"814 

440 

264 

202 

440 

2,480 

3, 680, 

8,190

717 

5,422 

596 

382 

5,422 

977 

2,540 

356 

381 

126 

943

IKK 76 03 6
82 FLOW OP RIVERS NEAR NEW YORK CITY. [NO. 76.

Turbidity, color, alkalinity, and hardness of streams Continued. 

WALLKILL RIVER Continued.

Date,

1902. 

Aug. 6_. _______________

Aug. 15 __--.._________

Aug. 38 ...... ......

Sept. 6___ ______________

Orage 

height.

rv f\Q

6 72

5.86

5.78

Color.

68

48

24

38

Turbidity.

25

8

5

5

Alkalinity.

62.0

83.0

88.0

57.0

Hardness.

71.0

84.0

89.0

61.0

Discharge in 

second-feet.

1, 150

518

169

145

TENMILE RIVER.

1901. 

Sept. 12 _-._ .___._..___

Oct. 26______. ______..__

Nov. 11. ______ _..-...._.

Nov.33.... .............

Dec. 2__.____________.__

Dec. 17_____.___________

Dec. 27_-_______. _______

1902. 

Jan. 10 __.........___...

Feb. 4_. ________________

Feb. 13.................

Mar.3___________. ______

May 15 ---_------------_

June 9 _._-._._______.._

June 30 _.-.-________.__

July 21_. _______________

Aug. 4 _ . . ____________

Aug. 19 ________________

Sept. 2 .................

5.90

5.00

4.75

4.80

4.75

8.41

6.54

5.75

6.30

5.00

«10.41

«6. 18

6.46

4.88

4.44

4.90

7.20

4.69

4.28

3.95

13

12

8

8

6

25

22

11

13

8

21

12

19

12

16

19

40

11

10

10

2

4

2

2

1

12

9

4

11

6

36

3

7

1

15

6

25

3

4

4

121.0

134.0

146.0

147.0

137.0

79.0

103.0

98.0

90.0

126.0

60.0

100.0

105.0

118.0

130.0

133. 0

88.0

129.0

138.0

139.0

142.0

151.0

154.0

152.5

86.0

106.0

103.0

104.0

137.0

61.1

103.0

112.0

123.0

139.0

160.0

90.0

141.0

160.0

155.0

364

166

120

129

120

1,120

524

328

460

166

&2,100

558

640

230

122

249

831

1,848

100

63

FISHEILL CREEK.

1901. 

Aug. 31 ________________

Aug. 31 -_.._____. ______

Sept. 4__. ______________

Oct.8________________..

«4.45

c4.57

^4 42

3.90

39.0

24.0

24.0

13.0

2

4

6

3

88

85

88

82 93.0

286

335

277

113

a All readings on this and following dates made on new 

gage placed 0.33 foot higher than the old gage.

& Approximate.

c Taken from daily gage height record.
PBBSSEY.] QUALITY OF EIVEE WATEE. 83

Turbidity, color, alkalinity, and hardness of streams Continued. 

FISHKILL CREEK Continued.

Date.

1901. 

Oct. 10.. ...-...--._.. ..

Oct.17--- _ .-- 

Oct. 25-_---------------

Oct.31 ___-,____--_____-

Nov. 5 -_____.__..,__--

Nov. 8.. __.____.__-.-

Nov. 18__... ...........

Nov. 15.. ..-._.....-.-.

Nov. 19 __---__-_--

Nov. 23___._ _______

Nov. 26 __..--.,. _____

Dec. 17- ___________

Dec. 19-_____ _________

Dec. 24_ -_--------._--.-

Dec. 26-___-_____-_____.

Dec. 81.. -...._.._.:.._.

1902. 

Jan. 2 . . . ...... .

Jan. 7 _ _ _ ______ ...

Jan. 9__ _____________ _.

Jan. 14___-____. ________

Jan. 16______ ____ _____

Jan. 21-_-____-______-__

Jan. 28_-_______-_ ______

Jan. 30____-_____. ______

Feb. 4-_ -.--------.

Feb. 7~--. -------

Feb. 11. ...__.... _______

Feb. 18-------------

Feb. 20----------------

Mar. 7 _ --------------

Apr. 18---------------

Apr. 22--.-. ------------

Apr. 24-.---.---.----. _

Apr. 29--. .---__ ________

May 15--.-. -----------

May 20--__- .-_----_-_--

May 22-___. _____--___-.

<» Likely too low

Gage 

height.

3.85 

4.50 

4.05 

4.00 

3.90 

3. 95 

4.35 

4.05 

3.95 

3.90 

4.30 

6.10 

5.10 

4.55 

4.55 

7.30

5.65

4.80 

4.65 

5.00 

4.35 

4.15 

4.90 

4.95 

5.50 

5.20 4.80' 

4.40 

4.40 

5.20 

4.60 

4.30 

4.10 

4.00 

3.90 

3.80 

3.70

Color.

11.0 

36.0 

16.0 

12.0 

12.0 

11.0 

17.0 

21.0 

13.0 

8.0 

22.0 

29.0 

21.0 

11.0 

13.0 

24.0

15.0 

12.0 

11.0 

5.0 

6.0 

6.0 

30.0 

9.0 

13.0 

11.0 

7.0 

5.0 

7.0 

11.0 

10.0 

9.5 

11.0 

13.0 

11.0 

11.0 

13.0 

b Taken

Turbidity.

2 

4 

2 

3 

5 

4 

4 

4 

4 

4 

5 

12 

7 

5 

4 

12

7 

3 

2 

3 

5 

3 

25 

4 

7 

6 

4 

6 

11 

14 

5 

4 

3 

3 

4 

3 

2 

from daily

Alkalinity.

94 

72 

88 

87 

85 

85 

80 

78 

79 

83 

74 

45 

58 

71 

74 

33

52 

66

70 

79

79 

82 

52 

63 

53 

72 

74 

80 

79 

48 

63 

70 

72 

79 

74 

76 

79 

gage heig

Hardness.

100.0 

«68.0 

.«84.0 

89.0 

89.0 

92.0 

87.0 

109.0 

94.0 

89.0 

84.0 

47.0 

64.0 

78.0 

79.0 

39.0

60.0

78.0 

81.0 

83.0 

85.0 

85.0 

55.5 

77.0 

60.0 

82.0 

81.0 

86.0 

87.0 

60.0 

' 68.0 

72.0 

76.0 

82.0 

85.0 

85.0 

85.0 

ht record.

Discharge in

second-feet.

100 

305 

154 

140 

113 

500 

250 

154 

126 

113 

233 

926 

409 

224 

224 

1,683

673 

300 

&253 

&370 

&172 

&128 

&334 

&352 

&594 

640 

430 

268 

268 

640 

345 

233 

169 

140 

113 

88 

66
84 FLOW OF EIVEES NEAE NEW YOEK CITY. [NO. 76.

Turbidity, color, alkalinity, and hardness of streams Continued. 

FISHKILL CREEK Continued.

Date.

1902.

May 28_. ....... .......

Jnne 10 -___ _________ 

June 16 ________ _______

June 19 .___._.. .......

JulyS....'..... .

JulyS. __ ....... _____

July 11. ................

Julyl6____._ .........

Aug. 4

Aug. 6 _________

Aug. 11

Aug. 13 ... ..___ ______

Aug. 19

Aug. 21

Sept. 1

Sept. 2

Sept. 5

Sept. 9

Sept. 12

Sept. 15 .... ___________

Gage 

height.

4.55

3.50

3.80 

3.50

3.50

3.60

3.50

3.40

3.10

3.60

3.40

3.60

3.60

3.20

3.10

2.90

2.80

2.90

3.00

3.05

3.20

Color.

34.0

11.0

19.0 

14.0

16.0

15.0

20.0

14.0

10.0

13.0

11.0

14.0

17.0

10.0

7.0

12.0

12.0

8.0

9.0

12.0

12.0

Turbidity.

5

3

4 

5

5

4

2

3

2

2

3

12

2

3

2

4

5

3

- 3

3

2

Alkalinity.

70

79

79 

84

86

81

83

86

89

81

82

74

74

84

84

94

93

89

85

73

Hardness.

80.0

81.0

85.0 

90.0

91.0

90.0

85.0

86.0

94.0

86.0

89.0

81.0

81.0

90.0

86.0

96.0

96.0

97.0

89.0

85.0

87.0

Discharge in 

second-feet.

405

115

175 

115

115

135

115

95

55

135

95

135

135

65

55

35

30

35

40

45

65

HOUSATONIC EIVER.

1901. 

Oct. 29 .

Nov. 13... --__- -_----.

Nov. 23

Dec. 28

1902. 

Jan. 11... -_.___._.___..

Feb. 14.. ......... ......

Mar. 18..-.. ...........

May3-------.-. .-.-.---

June 22 ________________

June 23 _ . . ............

June 25 ----------------

4.05 

4.83 

4.10 

5.16

5.00 

« 8. 30 

7.63 

6.10 

4.70 

4.50 

4.30

c

19.0 

25.0 

21.0 

14.0

13.0 

20.0 

24.0 

20.0 

24.0 

18.0 

14.0 

Backwate

3 

4 

5 

6

5 

5

11 

4 

3 

3 

r.

103 

102 

100 

91

89 

96 

53 

78 

89 

92 

93

103.0 

106.0 

105.0 

97.0

92.0 

103.0 

60.0 

86.0 

92.0 

94.0 

95.0

93£ 

1,86C 

98C

2,42(

2,14. 

8,00( 

8,27r 

4,45* 

1,58( 

1,17' 

1,07(
PRESSEY.] QUALITY OF RIVER WATER. 85

Turbidity, color, alkalinity, and hardness of streams Continued. 

HOUSATONIC RIVER Continued.

Date.

"1902. 

June 36 ___________'_ . _

July2___ .............

July4_ .. .............

Jtdy6. ................

Julys.-.------.--.. -

July 15.. ...............

JulylS--..-.-- _____ .

Jtdy23.-__-___:_. ______

July 35... .........._.. .

July 39..... ............

Aug. !____.___.___ _...

Aug. 5 ------- --------

Aug. 8---.- .____-.-___

Aug. 12................

Aug. 15 ________________

Aug. 19 ________________

Aug. 22 ................

Aug. 36 -__-__-._ .__,--

Aug. 39 . - ____.-____ . _ _ _

Sept. 2-____-, ..........

Sept. 5.-.. _-----__.--.

Sept. 9---.. _.--.-__--..

Sept. 13................

Gage 

height.

4.30

4.60

4.7(1

4.50

5.00

3.90

3.90

6.70

5.60

4.90

4.80

4.30

4.50

5.20

4.50

3.70

3.90

3.90

3.90

3.60

3.60

3.40

3.90

Color.

15.0

18.0

30.0

16.0

33.0

14.0

18.0

34.0

30.0

26.0

35.0

14.0

14.0

32.0

31.0

11.0

11.0

11.0

10.0

10.0

9.0

10.0

13.0

Turbidity.

2

3

6

2

3

5

23

12

4

4

5

3

3

3

4

3

2

1

1

2

Alkalinity.

94

90

91

QQ

91

85

95

63

73

88

88

103

102

73

85

96

96

103

96

98

104

105

97

Hardness.

95.0

90.0

93.0

93.0

94.0

101.0

98.0

75.0

82.0

91.0

94.0

109.0

107.0

83.0

86.0

106.0

99.0

107.0

104.0

113.0

HO.O

109.0

104.0

Discharge in 

second-feet.

1,070

1,400

1,530

1,177

3,145

750

750

5,119

3,050

1,800

1,650

983

1,177

2,300

1,177

750

750

750

640

640

490

750

Though the number of observations is not sufficient to give accurate 

curves, the results as shown in the tables have been plotted in Pis. IX, 

XI, XII, and XIII a and tentative curves drawn showing the relation of 

these qualities to the discharge of the stream. In the curves representing alkalinity and hardness the relation seems to be well marked. The 

diagrams show the relative hardness of the various streams, also ratio 

of decrease in hardness as the discharge increases. The regularity of 

the points enables one to prophesy with fair precision the alkalinity or 

hardness that might be expected at intermediate discharges. The 

turbidity and color* are, as might be expected, far more irregular. 

It would not be expected that during a rapidly rising flood we should 

find the same turbidity as at the time of general high water. The

a Since the diagrams were plotted many more observations have been obtained and are included 

in these tables. The diagrams have not been changed, as they are only intended to be suggestive.
86 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. 76.

effect, too, of a local shower on one tributary may affect the quality 

of the water much more than the same increase of water from another 

tributary, so that in an exhaustive study of a large river the effect of 

floods on each tributary is important, and should be studied rather 

than the river as a whole. Most of the tributaries of the streams 

under consideration are short, and storms would usually cover a large 

part of the drainage basin.

It is not considered that results have been obtained that are final 

upon these points, so that their publication is in the nature of a progress report. Measurements are being continued, and it is hoped that 

better curves can be constructed later. The curves representing turFIG. 8. New folding turbidity stick.

bidity and color are merely suggestions. It was not intended that the 

color curves of the Catskill and Tenmile should turn so far to the left 

at the upper part.

GAGE HEIGHTS AND DISCHARGE MEASUREMENTS.

In the following tables are given the mean daily gage heights during 

the years 1901 and 1902 at the stations established upon the Catskill, 

Esopus, Rondout, and Fishkill creeks, and Wallkill, Tenmile, and 

Housatonic rivers.

Following these tables are records of current-meter discharge measurements 011 these streams. These observations and measurements 

are being continued.
PRESSEY.] GAGE HEIGHTS. 87 

Mean daily gage height of Catskill Creek at South Cairo, N. Y.,for 1901.

Day.

1. . 

3...........

4. ..........

5...........

6...........

7.. .........

8...........

9...........

10...........

11 . .......

12...........

13...........

14...........

15 ....... .

16...........

July.

2.75

2.9

3.3

36

3.35

3.07

3.53

3.45

3.23

3.0

2.85

2.9

Aug.

2.55

2.6

2.55

2.4

2.4

2.5

3.35

3.05

2.87

2.8

2.77

2.65

2.55

2.5

2.5

2.5

Sept.

2 92

3.0

3 22

3.27

3.05

2.93

2.87

3.9

2.87

2.83

2.8

2.75

2.77

2.72

2.7

2.75

Oct.

2.8

2.75

2 7

2 7

2.67

2.67

2.62

2.65

2.6

2.65

2.6

2.6

2.65

2.8

3.1

3.15

Nov.

2 7

2 7

2.65

2.67

2.67

3.65

f> iy

2.7

2.65

3.65

*65

2.67

2.8

3.02

2.85

2.82

Dec.

2.65

2.65

2.65

3.3

3.3

3.32

3.32

3.3

3.35

5.35

4.62

4.45

3.95

6.95

12.8

5.6

Day.

17..........

18..........

19..........

20..........

21

22..........

23

24

25. .........

26.. ........

27 ...... .

28..........

29.. ........

30..........

31.... ......

July.

3.85

3.78

4 35

3.58

3.17

2.67

2.95

3.0

3.02

2 83

2.7

2 7

2.72

2.65

2.6

Aug.

2.4

2 52

2 62

3.67

2.75

3.05

Q 99

3.45

3.55

3.2

2.95

2.8

2.7

2.65

2.6

Sept.

2.82

2.97

2.97

2 83

2.8

2.8

2.77

2 73

2.67

2.65

2.65

2 7

3.8

2.83

Oct.

3.02

2.97

2.9

2.85

3.82

2.8

2.8

2.8

2.8

2.8

2.75

2.75

2.75

2.7

2.7

Nov.

2.77

2.75

*,75

2.75

2.75

2.75

2.7

2.7

2.7

2.7

2.65

2.65

2.65

2.65

Dec.

5.0

4.4

4.0

3.85

3.9

4.0

4.0

4.07

3.45

3.4

3.4

3.5

3.85

4.5

4.4

Mean daily gage height of Catskill Creek at South Cairo, N. Y.,for 1902

Day.

1.. ............

2. -, . ...

3... ...... .. 

4. ............ .

5 ------

6. _...._... ....

7. ......... ....

8. -------

9.-. -------

10. .......... 

11-. .... ........

12.- -------

13.- - - 

14. - 

15. ----------

16 ------

17-.. ---------

18. ..-. --------

19. - - 

20

21

22

23

24. 

25

26

27

28--... . :.....

29- 

30--.-.. -..

31 . 

Jan.

4.40

4.20

4.05

4.80

3.70

3.55

3.40

3.30

3.30

3.30

3.20

3.30

3.20

3.00

2.90

2.90

3.10

9.85

5.90

4.80

4.40

4.03

3.85

3.58

3.70

4 25

4.30

Feb.

4.30

5.05

5.20

4.45

4.40

4.40

4.30

4.26

4.30

4.25

4.40

4.50

4.70

4.95

3.10

3.20

3.40

3.50*

3.60

3.80

3.80

3.80

3.50

3.20

3.40

3.50

4.83

9.15

Mar.

11.70

9.68

6.70

6.80

6.35

5.40

4.10

4.10

4.30

5.20

5.75

9.10

9.20

7.50

5.45

7.40

9.43

6.85

4.15

4.50

4.00

4.55

5.58

5.48

5.05

4.93

4.83

5.03

.5.73

5.93

5.48

Apr.

5.35

5.88

4.95

4.88

4.90

4.65

4.40

4.60

11.65

8.25

6.98

6.48

5.50

4.95

4.78

4.58

4.35

4.25

4.20

4.20

4.13

4.10

4.03

3.85

3.90

3.80

3.83

3.73

3.95

4.10

May.

4.10

3.95

3.93

3.88

3.83

3.78

3.73

3.70

8.60

3.50

3.40

3.30

3.28

3.23

3.20

3.05

3.00

2.95

2.90

2.95

2.95

2.83

2.78

2.90

2.95

2.85

3.10

3.33

3.25

3.13

3.00

June.

2.95

2.88

2.80

2.83

2.88

2.88

2.85

2.90

2.80

2.75

3.70

2.65

2.78

3.75

2.70

2.75

2.90

3.88

2.78

3.85

2.80

2.80

2.80

2.78

2.70

2.68

2.65

2.60

2.80

3.88

July.

3.48

3.28

3.13

3.10

3.08

4.45

4.30

3.48

3.80

3.65

3.60

3.55

2.95

2.80

2.80

2.75

2 70

2.65

2.70

4.40

7.35

6.50

6.53

6.18

7.08

7.85

4 05

4 20

4 40

4.38

4.25

Aug.

4.50

5.58

4.38

4.13

3.85

4.45

4.20

3.93

3.80

3.65

3.55 3*55

3.45

3.15

3.20

3.15

3.05

2.93

3.05

3.10

3.03

2.98

2.93

2.83

2.75

2 7O

3 tn

2.73

2.85

2.98

3.08

Sept.

3.90

2.83

2.75

2.73

2.73

2.70

2.73

2.78

2.90

3.68

3.55

3.28

3.40

3.53

3.35

3.18

3.05

2.95

2.98

3.25

3.48

3.58

3.18

3.10

3.35

3.58

4.35

"4.70

9.95

7 20

Oct.

6.18

5.63

5.30

4.80i

4.60

4.53

4.40

4 83

4.05

3.90

3.93

5.08

4.60

4.35

4.15

4.25

3.93

3.83

3.80

3.83

3. IS

3.73

3.60

3.63

3.60

3.50

3.55

5.90

5.30

4.70

4.45

Nov.

4.30

4.15

4.05

3.95

3.90

3.83

3.77

3.73

3.65

3.55

3.50

3.55

3.63

3.53

3.50

3.40

3.40

3.33

3.30

3.28

3.30

3.20

3.20

3.15

3.20

3.30

3.85

4.13

3.80

3.63

Dec.

3.60

3.63

3.80

4.18

4.00

4.00

3.93

3.80

3.70

4.05

4.40

4.13

4.00

4.00

3.96

4.53

6.35

5.43

5.00

4.80

6.65

8.48

6.70

5.13

4.85

6.65

4.35

4.20

4.13

3.95

3.85

a 12 o'clock midnight, 16.1.
88 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. 76. 

Mean daily gage height of Esopus Creek, at Kingston, N. Y., for 1901.

Day.

1... ... ....

3... -----

3- - .

5- -- 

6.-.-----.

7. -- . 

8.. ......

9.. --------

10.. --------

11..- ------

13..--- ------

13.- 

 14. 

IS----- - 

16.--- 

July.

4.3

4.35

4.3 

4.4

4.4

4.25

4.35

4.3

4.3

4 3

3.95

4.3

Aug.

3.97

3.95

3.9 "

4.95

3.95

3.7

3.95

7.0

5.72

5.17

5.05

4.87

4 72

4.6

4.42 

4.42

Sept.

6.47

6.3

6.67

6.27

6.8

6.57

6.43 

5.02

6.17

4.95

6.02

4.87

4.9

4.87

4.72 

4.75

Oct.

4 52

4.62

4.7

4.52

4 42

4.3

4.47 

4.57

4.5

4.53

4.47

4.4

4.5

4 52

4.57 

4.65

Nov.

4.62

4.52

4.35

4.37

4.55

4.47

4.57 

4.47

4.32

4.32

4.45

4.57

4.6

4.45

4.37 

4.43

Dec.

4.6

4.52

477

5.45

4.62

4.72 

4.65

5.6

11.5

9.72

7.35

8 12

31.37

15.3

Day.

17 ...... ....

18 ...... ....

19 - 

30. -------

31

22_--------

23-- ..- 

24..-.. 

26 - -

36. ------

°7

38. --------

29__. . ------

30 --

31 

July.

4.05

4.05

4.6

4.15

4.1

3.9

4.U5 

4.0

3.9

3.97

3.92

3.H5

3.72

4 3

4.25

Aug.

4.37

4.54

4.5

4.77

5.95

6.63

5.92

7.35

7.67

6.52

6.02

5.87

5.72

5.45

5.32

Sept.

5.0

5.27

5.07

5.35

5.17

4.77

4.92

4.77

4.5

4.37

4.5

4.72

4.45

4.42

Oct.

4.47

4.42

4.6

4.77

4.77

4.67

4.67 

4.62

4.62

4.52

4.42

445

4.57

4.47

4.6

Nov.

4.3

4.37

4.52

4.5

4.47

4.53

4.45 

4.53

4.63

4.6

4.57

4.77

5.45

4.63

Dec.

10.55

9.05

8.1

8.0

7.75

7.3

6.85 

6.7

6.5

6.35

6.25

6.0

7.55

11.65

9.45

Mean daily gage height of Esopus Creek at Kingston, N. Y.,for 1902.

Day.

1. .............

2

3.... ..........

4. . .-- -----

5-- .....

6.. - . 

7-.. - ....

8 ___-

9...... ..__.-.-

10 -- -

11--- .

13 .

13. -----------

14. .

15- - .-

16- - 

17-- . 

18--....- -

19. .- 

30.. ------

31. -------------

22

23

24

35.. . .......

26.-...- .-

27- -

28

29.. -------

30. -----------

31. -----------

Jan.

8.30

10.35

9.95

8.40

7.65

7.30

6.95

6.65

6.50

6.40

6.35

5.88

6.00

5.93

5.60

5.58 

5.59 

5.30 

5.50

5.37

4.95

13.73

10.88

8.88

8.00

7.53

8.63

8.08

7.73

7.83

7.48

Feb.

7.25

7.45

9.35

7.72

7.52

7.16

6.70

6.47

6.14

6.25

5.94

5.88

5.77

5.60

5.58

5.53 

5.63 

5.39 

5.45

5.30

5.35

5.36

5.30

5.36

5.39

6.45

9.30

9.37

Mar.

12.10

16.83

15.75

11.07

9.45

8.95

7.90

7.68

8.85

9.20

9.05

9.80

11.85

11.83

9.98

9.33

a!8.28 

13. 10 

10.13

9.30

8.63

8.25

8.30

7.87

7.63

7.43

7.28

7.17

11.65

13.55

10.45

Apr.

9.35

8.69

8.05

7.64

7.33

7.03

7.18

7.38

13.10

13.86

11.60

10.22

9.41

8.78

8.35

7.. 90 

.7.58 

7.35 

7.10

6.93

6.80

6.78

6.93

6.88

6.58

6.38

6.a5

6.30

5.98

9.81

May.

8.95

8.18

7.78

7.70

7.43

7.11

6.98

6.74

6.55

6.40

6.33

6.10

5.96

5.88

5.70

5.70 

5.50 

5.33 

5.38

5.39

5.38

5.13

5.03

5.00

4.88

5.30

5.20

5.58

5.25

5.03

5.03

June.

4.85

4.83

4.76

4.83

4.70

4.73

4.55

4.63

4.63

4.68

4.58

4.45

4.53

4.58

4.40

4.46 

4.78 

4.94 

4.63

4.60

4.81

5.55

5.13

4.93

4.81

4.93

5.15

4.84

4.81

7.10

July.

6.38

6.19

6.00

6.40

5.99

6.19

6.16

6. as

5.80

5.58

5.50

5.34

5.15

5.05

4.98

4.99 

4.89 

4.80 

4.78

6.88

10.00

9.50

9.28

8.38

8.58

8.68

8.01

7.75

7.19

7.68

7.35

Aug.

7.09

7.95

7.10

6.90

6.53

7.08

6.90

3.43

6.18

5.88

5.83

6.25

5.73

5.58

5.38

5.30 

5.08 

5.10 

4.98

4.98

4.88

4.85

4.78

4.65

4.70

4.65

4.55

4.65

4.70

4.60

4.63

Sept.

4.45

4.48

4.43

4.33

4.38

4.33

4.38

4.38

4.38

7.68

6.00

5.49

5.53

6.18

5.85

5.53 

5.30 

5.13 

5.08

5.30

6.88

6.28

5-. 88

5.68

5.68

7.00

10.35

9.48

&S3.43

17.35

Oct.

13.38

11.68

10.10

9.50

8.60

9.64

8.68

8.18

7.85

7.40

7.15

9.10

8.47

8.00

7.60

7.33 

7.15 

6.95 

6.75

6.73

6.47

6.30

6.20

6.13

6.30

5.87

5.78

7.83

8.35

7.75

7.50

Nov.

7.28

6.75

5.83

6.55

6.55

6.25

6.47

6.35

6.13

6.00

7.85

7.95

5.85

5.78

5.73

5.63 

5.60 

5.60 

5.54

5.46

5.45

5.38

5.36

5.36

5.30

5.30

6.00

6.60

6.10

5.88

Dec.

5.90

5.70

6.19

6.43

6.33

6.18

6.35

6.60

6.45

6.00

6.35

6.55

6.35

6.40

6.43

6.65 

16.20 

13.86 

11.00

9.95

8.55

15.60

13.80

10.40

9.35

8.70

8.28

8.75

9.10

8. 97

8.05

Highest water at 1.30 p. m., 35.25. b Highest water at 1.30 p. m., 18.80.
PBBSSET.] GAGE HEIGHTS. 89 

Mean daily gage height of Rondout Creek at Rosendale, N, F., for 1901.

Day.

1..... ......

2_. ..----.. .

3.. ....... ..

4-....-.-...

5... .......

6...........

7...........

8. ....... ...

9.--..-....

10...........

11...........

12...........

13.. .........

14.. .........

15...........

16...........

July.

6.5

6.4

6.25

6.2

6.25

6.3

6.33

6.3

6.38

Aug.

7.57

5.5

6.3

6.25

6.17

6.35

9.75

7.35

6.92

6.62

7.17

7.42

6.87

6.55

6.50

6.52

Sept.

7.62

7.95

7.8

7.61

7.42

6.97

6.87

6.77

6.67

6.6

6.6

6.65

6.72

6.57

6.5

6.62

Oct.

7.26

6.85

6.95

6.8

6.7

6.62

6.55

6.55

6.52

6.45

6.42

6.42

6.5

7 25

7 72

7.37

Nov.

6.5

6.5

6.5

6.45

6.4

6.4

6.4

6.4

6.4

6.4

6.37

6 45

6.95

6.8

6.62

6.6

Dec.

6.55

6.4

6.5

6.85

6.87

6.85

6.92

7.0

7.2

9.2

9.25

8.22

7.75

8.97

16.75

10.6

Day.

18..........

19. .........

m. ------...

21 ...... .

22

23

24..........

25

26.... ......

27. ...... ...

28

29. - 

30- . 

31- --. 

July.

6.3

6.85

6.55

6.48

6.47

6.37

6.4

6.35

6.35

6.3

6.47

6.42

6.37

6.67

6.72

Aug.

6.5

6.75

7.0

6.95

8.75

8.15

7.5

9.0

9.4

8.1

7.47

7.15

6.95

7.42

6.72

Sept.

6.67

7.05

6.85

6.65

6.55

6.52

6.47

6.42

6.4

6.S5

6.32

6.3

7.05

7.41

Oct.

7.1

7.0

6.9

6.8

6.72

6.7

6.7

6.6

6.6

6.6

6.6

6.65

6.5

6.5

6.5

Nov.

6.55

6.55

6.55

6.5

6.4

6.35

6.4

6.5

7.6

7.25

6.97

6.87

6.8

6.8

Dec.

8.95

8.04

7.77

7.55

7.55

7.57

7.95

7.75

7.22

7.12

7.0

7.35

9.1

12.12

10.0

Mean daily gage height of Rondout Creek at Rosendale, N. Y.,for 1901

Day.

1.. ...... .....

2.___. ._..__.

3.............

4........ ..,_

5.. ....... ....

6. ........... -

r.. ... 

8... ........ ..

9... __..!... ..

10.............

11...... ....

12.............

13.. . ......... _

14.. ...... .....

15.... ...... ...

16_. ...... .....

ir.. .......... .

18.............

19..... ........

30. ............

21..., .........

22..... ........

23..... ........

24.............

25..... ........

28........... .

27.............

28.............

29.............

30.............

31.......... .

Jan.

8.73

7.90

7.90

7.90

7.90

7.88

7 58

7.28

7.13

7 08

7.10

7.35

6.95

6.73

6.83

6.90

6.78

6.70

6.78

6.70

6.73

14.68

9 83

8.35

7.85

7.68

8.95

8.00

8.18

8.60

Feb.

8.98

8.95

9.75

9.35

9.70

9.25

9.00

8.83

8.58

8.05

8.18

8.05

7.98

7.88

7 80

'7.65

7.53

7 60

7.35

7.43

7 43

7 40

7.43

7.48

7 UK

8.23

10.68

13 10

Mar.

17.30

14.23

12.53

9.75

8.70

8.05

7.95

7.65

9.40

9.70

9.30

9.70

11.05

10.15

9.15

8.80

13.10

9.95

8.65

8.25

8.08

8.00

7.88

7.80

7.63

7.45

7.88

7.33

9.85

9.53

8.63

Apr.

8.18

7.85

7 58

7.58

7.35

7.25

7.60

8.10

12.28

11.40

9.75

9.15

8.63

8.15

7.85

7.65

7.50

7.38

7 25

7.18

7.10

7.05

7.00

6.90

6.88

6.98

6.95

6.83

6.78

9.38

May.

8.25

7.70

7.70

7.75

7 50

7.33

7.28

7 11

7.03

6.93

6.88

6.88

6.83

6.68

6.63

6.70

6.60

6.63

6.60

6.60

6.58

6.50

6.48

6.45

6 40

6.80

6.88

7.20

6.85

6.60

6.63

June.

6.58

6.48

6.55

6.63

6.48

6.40

6.48

6.45

6.48

6.38

6.30

6.35

6.35

6.38

6.35

6.35

6.50

6.45

6.30

6.43

6.43

7.10

6.70

6.50

6 40

6 43

6.50

6 43

6.45

7.70

July.

7.08

6.90

6.98

7.70

7 23

7.13

7.00

6.88

6.85

6.65

6.58

6.53

6.50

6.45

6.35

6.40

6.33

6.30

6.33

7.53

8.93

9.18

8.38

«9.94

W 3i

8.95

8.23

7.80

7.38

7.80

7.33

Aug.

7.70

8.35

7.60

7.28

7 08

7.25

7.33

7.03

6.93

6.83

6.80

6.60

6.80

6.70

6.55

6.58

6.50

6.45

6.40

6.40

6.38

6 48

6.40

6.40

6.33

6.30

6.28

6.25

6.33

6.30

6.30

Sept.

6.25

6.20

6.13

6.15

6.10

6.18

6.20

6.20

6.23

7.00

6.58

6.40

6.45

6.68

6.48

6.35

6.25

6.20

6.18

6.25

6.50

6.40

6.23

6.25

6 45

9 40

9.75

8.68

614.09

10.78

Oct.

10.03

9.28

8.43

7.90

7.80

8.78

8.00

7.65

7:38

7.18

6.95

9.75

8.65

8.00

7.57

7.35

7 23

7.07

7.07

7.00

6.95

6.90

6.80

6.80

6.80

6.73

6.63

9.38

8.60

7.83

7.45

Nov.

7 25

7.05

7.03

7.00

6.90

6.87

6.95

6.85

6.80

6.78

6.73

6.73

6.73

6.70

6.70

6.70

6.65

6.65

6.68

6.65

6.65

6.65

6.60

6.60

6.55

6.70

6.75

6.90

6.88

6.80

Dec.

6.73

6.70

6.90

7.20

6.88

6.80

6.95

6.98

6.88

7.10

7.08

7.00

6.95

7.15

7.50

8.35

12.95

10.00

8.80

8.30

8.35

13.45

10.58

9.55

8.50

8.10

8.87

7.45

7 27

7.20

7.20

«Highest water, 12.65, at 7 p. m. & Highest water, 15.6, at 3 p. m.
90 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. 76.

Estimated diversion from Rondout Creek to Delaware and Hudson Canal, Rosendale, N. Y., 1902, in second-feet.

Day.

1. _ ...

Z. .............

3____. -_--_____

4-........ ..

5. .............

6-.. ........

7_--_ .......

8. ... .. _

9____ ___ _

10.- ... .

11. 

12. ........ 

13. ....... .....

14---..,-.----.

15-. ... --

16.... ..... ._

17. - 

18....... ,..

19.--. -----

20-..- ---....

21 -

22... . 

23- ...- -

24- 

25. . -

26. ... -

27.- - -

28-- ... 

29.... . ------

30- ..- 

SI.. -. -

Jan.

-------

-------

-.-...-

.......

_ ----- _

-------

-------

.......

.......

-------

-------

...... .

Feb.

---..._

.......

.......

.......

--...-_

.......

-----

---..._

--..--.

.......

-------

.......

-------

-------

Mar.

-------

-------

.......

- ... .

--..--.

 ....

. ---_- _

-------

.......

-------

15.8

11.4

12.3

15.3

16.9

16.4

21.8

Apr.

15.5

17.7

21.5

22.0

17.9

-------

30.4

30.2

18.4

14.3

20.7

19.2

-------

35.4

35.7

24.2

25.1

26.1

25.6

25.9

26.7

24.1

23.3

23.4

22.8

37.1

25.2

25.8

22 5

May.

23.6

15.0

24.6

-------

27.6

23.1

24.8

24.3

24.6

24.5

24.3

24.1

25.0

34.1

34.5

23.8

-------

24.3

24.6

23.1

23.6

25.6

24.3

-------

31.1

28.0

26.5

26.3

30.7

24.1

24.0

June.

35.2

30.8

11.6

25.3

19.5

21.8

23.8

35.9

34.9

33.8

27.5

23.6

-------

33.3

33.6

24.3

23.8

23.9

24.4

32.1

20.1

22.6

23.8

19.8

32.6

26.7

23.7

July.

24.2

23.8

23.1

-------

24.1

------

33.1

32.7

24.3

35.3

26.1

31.8

-.-..-_

25.3

25.3

24.2

26.0

25.1

22.7

23.8

25.6

32.8

30.6

19.0

23.8

25.6

31.6

23.6

26.4

9Q 8

Aug.

36.0

35.6

33.8

34.5

38.5

34.5

23.8

24.0

-------

24.0

24.5

24.6

36.0

24.8

24.5

..-.--_

25.5

24.3

23 8

25.1

25.6

24.3

-------

23.8

23.3

26 1

23.5

25.8

23.0

24.3

Sept.

25.3

22.5

24.3

25.3

25.8

.......

25.0

33.5

24.3

24.3

25.1

23.2

-------

36.5

25.6

25.8

23.3

24.8

23.0

24.3

23.8

24.0

25.1

32.8

32.6

20.3

22.1

34.0

Oct.

32.6

22. 4

26.1

35.8

-------

32.2

23.1

22.4

21.9

33.8

32.1

30.4

30.6

30.5

19.5

19.5

19.7

-------

31.3

23.5

31.0

31.3

23.0

20.4

-------

32.8

23.8

24.3

23.0

25.0

22.2

Nov.

22.5

-.-.-.-

31.0

23.5

21.5

23.3

24.2

34.8

--...-_

---..-_

-------

--.-...

-----

...... .

--..--.

...... .

-------

_. ..-- _

.......

--_-». .

Dec.

------

......

------

-.-...

------

------

------

......

--..--

--.-.-

------

------

--....

------

......

------

------

---..-

......

------

Mean daily gage height of Wallkill River at New Paltz, N. Y., for 1901.

Day.

1 .... 

8 

4. 

5 

6-. .-_-

7

9 

10 .- 

11---------

12 . 

13 . 

14 ______

15 - 

16. . 

July.

7 27

7.23

6.93

6.65

6.53

7.33

7.60

7.15

6.85

6.55

Aug.

6.10

5.90

5.97

6.00

6.45

"6.45

12.05

11.25

9.30

9.15

9.10

8.05

7.70

7.15

7.40

7.10

Sept.

9.30

9.85

9.75

9.35

8.55

8.35

8.05

7.70

7.47

7.45

7 25

7.05

7.15

6.95

6.65

6.75

Oct.

7.45

7R5

715

7.00"

6.95

6.85

6.65

6.35

6.30

6.30

6.30

6.20

6.35

7.50

7 85

Nov.

6.00

6.00

6.00

6.00

6.05

6.10

6.00

5. 95

5.85

5.75

5.65

5.95

6.40

7 00

6.90

fi PLfl

Dec.

6.35

6.05

6.00

6.30

6.35

6.65

6.60

7.30

10.00

12.30

11.70

10.30

10.05

10.60

13.30

13.85

Day.

17 

18..... .

19. -- 

SO .. .

21. ........

OlTi

33- ......

24. .___....

25

26

27

28.........

29 

30.........

31. 

July.

6.37

7.15

7.98

7.30

6.50

6.a5

6.25

6.05

6.00

6.00

5.85

5.85

5.85

5.80

5.95

Aug.

6.75

9.26

11.15

10.15

10.25

10.25

10.15

9.70

14.30

12.00

11.25

10.60

9

QA

9.15

Sept.

705

7 62

7.65

7.45

7.30

7.10

6.95

6.82

6.65

6.50

6.35

6.35

6.65

7 35

Oct.

7.50

7 27

7.15

6.95

6.70

6.45

6.32

6.30

6 20

6.12

6.10

6.10

6.10

6.10

6.50

Nov.

6.25

6.05

6.15

6.35

7.30

8.10

8.65

8.35

8.10

7.45

6.95

6.85

6.65

6.45

Dec.

13.10

13.65

13.75

12.95

11.70

10.70

10.45

10.15

9.55

9.00

9.35

9.70

11.80

19.35

19.20
PBESSEY.] GAGE HEIGHTS. 91 

Mean daily gage height of Wallkill River at New Paltz, N. Y., /br 190S.

Day.

1 -___.--

Z . -------

3 -.. -

4.- ...

5 .

6_ ._ 

7.... ...... .,..

8 ---_-.--

9. ------- .-

10 

11. 

12. .-- ----

13 

14 

15 -------

16.- ------

17. . ---------

18. ------

19. 

20

21

22 

23 

24 

25

86 

27. -------

28... ..----

29

30 

31 

Jau.

15.15

13.25

12.95

12. 10

10.45

10.70

10.20

8.70

9.15

8.85

8.75

8.20

8.05

8.05

8.00

8.00

7.70

7.55

7.50

7.20

7.20

18.50

17.65

13.55

13.15

12.20

12.85

12.65

11.15

9.50

9.25

Feb.

8.75

8.75

10.65

9.70

9.75

8.90

8.15

7.85

7.78

7.70

7.55

7.55

7 40

7.35

7.15

7.10

7 20

7.15

7.08

7.00

7.05

7.05

7.10

7 25

7.30

7.75

11.40

12.75

Mar.

23.53

23.80

«24.65

23.75

20.25

15.20

13.20

12.70

14.90

16.45

15.90

16.10

17.05

16.50

15.00

14. 65

15.40

13.75

11.75

10.60

10.30

10.20

9.75

9.60

9 45

9.00

8.50

8.20

10.20

11.05

9.90

Apr.

9.35

8.95

8.65

8.20

8.00

9.70

7.70

8.40

613.65

13.50

12.20

11.65

10.65

9.80

0 OK

8.65

8.20

8.00

7.85

7.60

7 45

7.35

7.15

7.10

6.95

6.85

7.00

6.75

6.65

ell. 75

May.

10.25

8.95

9.15

8.85

8.35

7 95

7.50

7 45

7.35

7.10

6.80

6.65

6.60

6.55

6.50

6 45

6.35

6.30

6.30

6.30

6.30

6.30

6.25

6.20

6.20

6 45

8

0ft

9 9D

8.40

8

*y\

7.90

June.

7 50

7 25

7.05

6 90

6.55

6.35

6.30

6.25

6.30

6.50

6.35

6.30

6.20

6.15

6.10

6.20

6 25

6.15

6.13

6.10

6.13

6.33

6.40

6.35

6.20

6.20

6.10

6.03

6.13

7.00

July.

7 25

7.15

7.50

7.58

7.08

6.78

6.53

6.35

6.23

6.10

6.00

6.00

5.90

5.78

5.70

5.70

5.73

5.58

5.55

6.10

7.78

8.65

7 40

"11. 00

d!4.00

o in

8.50

7.80

7 45

7 45

8.45

Aug.

9.50

9.10

8.75

8.60

8.30

7.95

7.85

7.65

7.30

7.05

6.90

6.80

6.75

6.68

6.60

6.53

6.43

6.38

7 28

6 20

6.15

6.10

6.05

6.10

6.05

6.00

6.00

P; os

8 at?

6.95

6.40

Sept.

6.10

6.05

6.00

5.88

5.78

5.70

5.60

5.50

5.50

6.10

6 45

6.30

6.35

6 45

6.25

6.15

6.05

5.95

5.80

5 90

5.90

5.90

5.90

S on

6.15

Q fiS

12.00

U on

13.45

10.35

Oct.

10.25

10.85

10.15

9.65

9.60

mio

9.45

9.00

8.55

8.40

8.25

12.45

11.90

10.50

9.70

9.35

9.00

8.60

8.60

8.15

7.95

7.65

7.47

7.37

7.15

6.95

6.85

11.65

11.25

9.45

8.95

Nov.

8.65

3.35

8.15

7.95

7.65

7.50

7.50

7.65

7.15

6.95

6.75

6.70

6.60

6.60

6.60

6.50

6.50

6 ^[\

6.50

6.50

6.40

6 40

6.65

6.30

6.30

6.35

7.35

T? QP;

7.10

6.95

Dec.

6.80

6.70

7.50

7.95

8.10

8.55

8.10

7.70

7.70

7.65

7.60

7.60

7.55

7.50

7.50

7.50

12.20

12.25

12.30

12.30

12.95

19.00

19.65

17.20

16.25

15.30

14.20

14.20

13.80

12.30

11.75

o Highest water 84.80 at p. m. 

& Highest water 14.6 at p. m.

« Highest water 15.4 at 8 p. m. 

d Highest water 16.6 at 9 p. m.

« Highest water 12.6 at p. m.

Mean daily gage height of Fishkill Creek at Glenham, N. Y.,for 1901.

Day.

I.. ...... ...

2........... 

3.. ........ .

I.. .........

5.. .........

6-. ------

7---. .--.

8... .... .

9 -

10.. ........ .

11.- 

12.. . ....... .

13.. ....... ..

14..-....-..

15. 

16. 

July.

3.90

3.90

3.80

3.78

3.83

3.80

3.73

3.70

3.65

Aug.

3.95

3.82 

3.77

3.67

3.65

3.65

4.70

5.55

4.77

4.35

4.12

4.07

4.02

3.80

3.90

3.82

Sept.

4.57

4.60

4.47

4.42

*4.30

4.15

4.17

4.10

4.07

4.02

4.05

4.37

4.32

4.15

4.10

4.25

Oct.

4.05

3.97 

4.10

4.10

4.00

3.92

3.90

3.87

3.85

3.85

3.85

3.80

3.80

4.30

4.85

4.83

Nov.

3.97

3.95 

3.95

3.95

3.90

3.90

3.92

3.95

3.90

3.87

3.87

3.92

4.32

4.17

4.05

4.00

Dec.

^ on

3.68 

4.05

4.08

4.10

4.85

4 28

4.18

4.05

4.73

5.33

4.83

4 60

4.68

6.78

7.45

Day.

17- 

18_ _ 

19 

20 ..

21 . 

22. ........ .

23

24.... ......

25

26

27- .

28

OQ

30. .........

31 

July.

3.73

4.23 

4 00

3.90

o 77

3.70

3.65

3.65

3.65

3.63

3.60

3.45

3.57

4.35

4.15

Aug.

3.85

5.07 

4.70

4.40

4.45

4.95

4 62

4.70

6.40

6.55

5.65

5.20

4-m

4.70

4.57

Sept.

4.15

4.22 

4.12

4.02

4.03

4.00

3 92

3.90

3.87

3.85

3.80

3.87

395

4.20

Oct.

455

4.40 

432

4 22

4.20

4.15

412

4.10

4.05

4.00

4.00

4.00

4.00

4.00

397

Nov.

3.95

3.95 

3.95

3.95

3.93

3.93

3.90

3.90

4.35

4.33

4.13

4.03

4.00

&98

Dec.

6.18

5.53 

5.15

4.98

4.78

4.73

4.73

4.55

4.60

4.55

4.85

4.15

5.75

8.28

7.50
92 FLOW OF EIVEES NEAE NEW YOEK CITY. [NO. 76. 

Mean daily gage, height of Fishkill Creek, at Glenham., N. Y..for 1902.

Day.

I...... . .....

3 . .........

4... ...........

5_. ........

6_. . ........

7........-.-.-.

8.... ..........

9.__.__ _______

10 __. . ... 

lllS..............

14..............

15.............. 

16..............

18. . ......

19.... .......

20.......... ...

21...... ....... 

23.............

S3.............

24..... .........

85..............

26.......... .

27. ............

28..............

29.. . ........

30..............

31..............

Jan.

6.05

5.65

5.50

5.30

5.18 

4.95

4.80

4.70 

4.65

4.63 

4.60

4.58

4.75

5.00

4.70 

4.35

4.28

4.85

4.25

4.18

4.18

5.88

6.55

5.15

4.75

4.63

5.00

5.00

4.95

5.05

4.95

Feb.

5. TO

4.75

5.63

5.55

5.58 

5.28

5.25

5.00 

5.18

5.05 

4.75

4.80

4.60

4.40

4.33 

4.35

4.48

4.38

4.33

4.35

4.38 

4.85

4.85

4.90

4.70

4.85

5.88

7.10

Mar.

13.00

10.00

8.78

6.70

5.80 

4.95

5.05

5.15 

5.90

7.75 

6.95

6.50

6.70

6.63

5.98 

5.65

6.73

6.45

5.70

5.30

5.30 

5.23

5.13

5.00

4.85

4.75

4.70

4.55

4.85

5.40

5.05

Apr.

4.90

4.78

4.68

4.60

4.53

4.45

4.53

4.63 

5.13

5.65 

5.53

5.38

5.05

4.90

4.80 

4.70

4.60

4.58

4.50

4.40

4.35 

4.30

4.23

4.15

4.05

4.05

4.13

4.08

4.00

4.83

May.

5.48

4.93

4.70

4.73

4.63 

4.45

4.a5

4.30 

4.30

4.10 

3.90

3.98

3.95

3.90

3.90 

3.90

3.80

3.70

3.75

3.80

3.83 

3.68

3.68

3.60

3.60

4.20

4.15

4. 58

4.23

4.03

3.90

June.

3.83

3.70

3.60

3.70

3.70 

3.55

3.50

3.85 

3.85

3.75 

3.60

3.50

3.40

3.43

3.50 

3.50

3.95

3.70

3.50

3.53

3.50 

3.75

3.60

3.50

3.40

3.50

3.40

3.30

3.35

4.08

July.

3.70

3.53

3.45

3.85

3.60 

3.70

3.70

3.55 

3.45

3.38 

3.40

3.30

3.23

3.20

3.13 

3.13

3.10

3.10

3.08

3.20

4.15

4.70

4.65

4.10

4.18

4.10

4.05

3.90

3.80

4.20

3.95

Aug.

3.80

3.70

3.60

3.60

3.50 

3.43

3.48

3.40 

3.40

3.30 

3.50

3.85

3.65

3.48

3.40 

3.35

3.28

3.30

3.20

3.15

3.10 

3.15

3.10

3.10

3.15

3.05

aoo

3.00

2.95

2.95

2.90

Sept.

2.90

2 80

2.95

2.73

2.90 

2.95

2.90

2.95 

3.00

3.33 

3.25

3.08

3.30

3.23

3. 20 

3.15

3.15

3.18

3.00

3.05

3.03 

3.15

3.08

3.13

2.95

3.48

3.60

3.60

4.80

4.75

Oct.

4 25

4 20

4.00

3.83

3.83 

4.20

4 20

3.93

3.85

3.78 

3.70

4.95

5.03

4.08

4.35 

4.20

4.80

4.00

4.00

3.95

3.90 

3.80

3.80

3.70

3.75

3.73

3.70

4.65

5.43

4.93

4.55

Nov.

4.40

4.33

4 20

4.15

4.05 

4.03

4.00

4.00 

3.93

3.90

3.88

3.88

3.88

3.88

3.80 

3.83

3.80

3.70

3.70

3.68

3.63 

3.60

3.60

3.63

3.63

3.68

3.95

3.88

3.80

3.70

Dec.

3.70

3.73

3.88

4.03

3.98 

3.70

3.70

3.80 

3.98

4.05 

3.85

3.90

4.05

4.10

.4.30 

4.40

6.65

7.55

6.50

5.98

5.50

7.75

8.05

7.00

5.95

5.60

5.40

5.05

4.93

4.90

4.77

Mean daily gage height of Tenmile River at Dover Plains, N. Y., for 1901.

Day.

!.___. ____..._ ..

2................

3.... ............

4.. .......

5.... ............

6.. ..............

7...... ...._.....

8.. .......... ....

9................

10................

11. ........... .

12..-.-.. ......

13... ........._...

14................ 

15.... ......__....

16................

Sept.

 - -

Oct.

5.02

4.80

5.00

5.00

4.87

4.85

4.75

4.65

4.65

4.65

4.65

4.65

4.57

6.27

6.82

6.42

Nov.

4.95

4.90

4.90

4.85

4.87

4.87

4.85

4.80

4.77

4.75

4.67

4.97

5.90

5.50

^ 97

5.10

Dec.

4.65

4.67

4.95

5.50

6.05

5.40

5.02

4.80

4.77

6.35

6.72

6.35

6.12

6.47 

11.17

9.50

Day.

17. 

18...............

19.. ............ .

20...............

21. .-..._.-......

22

33

24.. ....... ......

85

36.... .......... .

27 ---------

382:::::::::::::::

30 ........... 

31. - -

Sept.

5.00

5.30

5.00

4.85

4.80

4 80

4.70]

4.60

4.57

4.50

4.55

4.37

4 77

5.50

Oct.

6.17

5.87

5.63

5.50

5.47

5.40

5.35

5.27

5.20

5.00

5.02

5.05

4.97

4.95 

4.93

Nov.

5.05

5.90

4.87

4.87

4.85

4,79

4.75

4.75

5.20

5.10

4.90

4.95

4.85

4.72

Dec.

8.15

7.20

6.85

6.35

5.95

5.75

5.92

5.90

5.95

6.40

6.47

6.50

10.70

13.30 

10 22
PBBSSBY.] GAGE HEIGHTS. 93 

Mean daily gage height of Tenmile River at Dover Plains, N. Y., for 190S.

Day.

1. ......... ....

2.. ........... .

3 

i. .............

5 ....

6. .......... ...

8. .............

9. .............

10..............

U. .............

12

13.. . 

14. ....... ......

15.. . 

16.............

17.. 

18. .... . ..

19..- . - 

20-..... -..

21

22

23

24.. -......-.

25 . .

26-.... ........

27

28.. -.-...... 

29.-...-. .... 

30. .. .....-. 

81 

Jan.

r.7o

r.oo

6.95

6.10

6.08

6.15

6.10

5.80

5.65

5.55

5.60

5.55

5.38

5.25

5.25

493

465

5.05

5.10

5.05

5.05

11.95

8.10

6.35

5.80

5. TO

7.80

7.45 

6.55 

6.25 

5.50

Feb.

5.40

6.10

6.95

6.08

5.50

5.35

5.10

5.10

495

490

5.10

5.10

4 80

6.75

5.25

5.15

5.05

fl fK

5.00

4.85

i 7fl

4.68

4 40

i vi

4.65

5.83

8 45

9.73

Mar.

1415

14.10

all. 43

8.35

6.95

5.90

6.25

6.25

8.90

10.60

9.15

8.70

 9.10

8 40

7.70

7.30

8.15

7.60

6.55

6.13

6.10

6.15

6.20

6 9^

6.05

fi on

fl SK

7.43 

7.60 

7.30 

6.90

Apr.

6.60

6.45

6 25

5.98

5.80

5.90

6.13

6.40

6.80

7.60

7.10

6.60

6.30

6.15

6.10

5.90

5.88

5.68

5.58

5 45

5.35

5.23

5.13

5.03

4.95

4.95

5.30

5.25 

5.30

r.oo

May.

6.95

6.95

6.50

6.20

6.05

5.90

5.75

5.55

5.35

5.23

4.95

4.85

4.85

480

4 80

4.75

4.65

4.60

4.65

4.68

4.58

i vi

4 40

4.30

4.30

fl flU

5.30

5.50

5.18 

4.80 

4.70

June.

4.55

4.50

4.40

4.55

4.48

4.35

4 25

4.48

4.55

4 48

4.30

4.20

4.75

470

435

4 45

465

4 45

4 28

4.15

4 40

4 60

438

433

4.15

4.10

4.05

4.05 

4.10 

4.70

July.

4.45

4 25

4.35

5.53

4.38

4.60

4.63

4 33

4.38

4 23

4.20

4.10

4 15

3.90

3.88

4.30

4.18

3.88

4.03

4.65

ft OR

1 If!

6.35

5

7P\

5.68

5.50

5.30

5.40 

5.25 

5.65 

5.25

Aug.

5.10

4.88

4.65

4.63

4.53

4.43

4.65

460

4.45

4.43

5.68

5.03

5.95

4.78

4.68

423

4.18

4.15

4.15

4.18

4.25

4.23

4.10

4.08

4 08

<l QR

3.93

3.85 

3.83 

3.80 

3.85

Sept.

3.90

3.83

3.80

3.90

3.83

3.80

3.85

3.88

3.95

4 23

3.95

3.90

4.10

4.23

4.13

403

3.88

3.88

4.03

428

4.33

413

415

408

405

4.08

4.65

6.50 

7.75 

5.98

Oct.

5.78

5.85

5.43

5,10

5.30

5.85

5.13

490

4.83

5.00

6.10

6.93

5.87

5.63

5.43

5.25

5.15

5.27

5.20

4.90

4.80

4.75

473

4.65

4.55

4 60

7.05 

7.10 

6.37 

6.00

Nov.

5.75

5.50

5.43

5.33

5.30

5.25

5.10

5.08

5.00

4.93

4.83

4.78

4.83

480

4.83

4.73

4.65

4.60

4.53

4.55

4.58

455

453

458

4.70

4 93

4.78 

4.65 

4.33

Dec.

4.45

4.48

4.80

4.90

4.73

4.78

4.80

4.85

5.13

5.08

4.85

4.80

480

493

5.08

6.15

10.47

9.13

8.28

7.70

7.74

11.50

10.66

8.58

7 95

7 48

7.05

a Readings on new gage from this date, datum 0.33 above former gage. 

Daily gage height of Housatonic River at Gaylordsville, Conn., for 1900.

Day.

I.. -. . _ .___.

2 ........................

3 -. _ ._

^... .....................

?>.. ......................

Q.... ....................

1 ........................

^.... ....................

9 ........................

W.... ....................

11 

12-....-. ...-.

13... ...... ...... ......

14.... . ... 

15 . 

16 

Oct. Nov.

3.2

3.1

3.1

2.9

3.0

2.9

2.8

- 3.2

3.5

4.1

3.9

3.7

3.6

3.7

3.7

3.7

Dec.

4.9

4.6

4.3

4 2

5.6

5.8

5.4

5.1

4.9

4.5

4 2

4 2

4 2

4.2

Day.

17 

18. ... ...... .......... .

18. . ... ........

20 . 

01

22

23

24. 

25 

26 . 

27... ..-. -------

08

29 ... 

30 

31 

Oct.

2.9

3.1

3.2

3.1

3.1

3,1

3.1

3.0

Nov.

3.6

3.5

3.6

3.7

4.1

4.0

3.9

3.9

3.8

4.6

5.5

5.4

5.1

4.9

Dec.

4.8

5.1

4.3

4.2

4.1

4.2

4.0

3.9

4.2
94 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. 76. 

Daily gage height of Hoiisatonic River at Gaylordsville, Conn., for 1901.

Day.

1.... ..... 

2 

3 -------

i.... ..........

5 ---------

6.. ___'_ 

1.... .......... 

8..- -- 

9...... --.

10.. -------- 

11 .----..-. 

12

13 .

14. --------

15 .

16. --------- 

17 ---------

18 ---------

19... --------

20

21 .... ......

oo

23 ------- 

24. . -----------

25 ------- 

26 -- - -.

27.- --

28

29-. ------- 

30 - 

31. . .

Jan.

4.40

4.00

(«)

(«)

(«)

4.50

4.50 

4 40

4.20

4.40 

4.10

4.70

4.00 

3.50

3.70

3.80 

4 40

4 00

3.50 

3.40

3.80 

3.60

3.70 

Q fai

3.60 

3.70

3.80

3.70

3.50 

3.50 

3.40

Feb.

3.20 

3.30

3.30

3.30-

3.10

3.00

3.40 

3.50

3 40

3.70 

3.50 

3.30

3.40

3.70

3.60

3.40 

3.40

3.40

3.20 

3.30

3.40 

3.50

3.40 

3.20

3.30 

3.00

3 40

3.30

Mar.

3.30 

3.50

3.60

3.60

4.10

S on

3.90 

3.60

3

Zfl

7.50 

8.20 

t fai

6.00 

n f»fl

5.60

5.60 

4.60

4.60

4.80 

4 80

10.00

8.70

7.40 

7.10

6.60 

6.60

7 20

6.90

6.60 

6.20 

5.80

Apr.

5.30 

5.30

5.30

6.10

6.60

6.50

7.30 

8.30

8.00

7.80 

7.20 

6.70

6.50 

6.10

5.90

5.90 

5.50

5.30

5.20 

5.20

7.30 

9.30

8.40

fi <VI

8.80 

7.85

7 20

6.90

7.00 

6.40

May.

6.20 

6.20

6.40

6.30

6.00

5.60

5.50 

5.30

5 9fl

5.20 

5.70 

6.30

6.10 

6.00

5.60

5.50 

5.30

5.30

5.80 

6.20

6.20 

5.80

5.80 

5 fin

6.80 

6.70

6.80

6.80

6.90 

6.80 

6.60

June.

6.20 

6.00

5.70

5.50

5.50

5.20

5.20 

5.50

5.50

5.40 

5.20 

4.90

4.80 

4.60

5.20

4.70 

4.50

4.20

4.30 

4.20

4.10 

4.00

4.30

4.70

4.60 

4.30

4 20

4 00

4.00 

3.80

July.

3.60 

3.50

3.80

3.90

3.70

4 00

4.00 

3.80

3.80

3.80 

3.90

4.00

4.00 

3.90

3.60

3.50 

3.70

3.60

3.60 

3.60

3.60 

3.50

3.40 

3 60

3.60 

3.50

3.50

3.50

3.50

3.40 

3.70

Aug.

3.50 

3.70

3.50

3 40

3.30

3.30

3.90 

4 80

4 40

4.10 

4.00 

3.90

3.70 

3.70

3.60

3.70 

3.60

3.70

4.00 

3.80

4.10 

4 70

4.80 

4 80

6.80 

6.70

5.70

5 20

4.80 

4.60 

4.40

Sept.

4.30 

4.40

4.70

4 60

4 60

i di\

4.40 

i di\

4 00

3.90 

4.00 

4.20

4.00 

4 00

4 00

4.10 

4.10

4.70

4.50 

4.40

4.20 

4.20

4.00 

3.80

3.90 

3.80

3.80

3.80

3.90 

4.40

Oct.

4.30 

4 20

4.50

4.60

4 40

4.20

4.00 

Son

4.00

4.00 

3.80 

3.80

3.80 

5.20

6.70

6.00 

5.80

5.30

5. ID 

4.90

4.80 

4.60

4.50 

4 40

4.30 

4.30

4.20

4 00

4.00 

4.30 

4.10

Nov.

4.00 

4.20

4.00

3.80

3.70

4.10

3.80 

3.80

3.80

3.70 

3.50 

3.60

4.80 

4.90

4.70

4.60 

4.50

4.40

4.20 

4.30

4.20 

4.20

4.10 

4.20

4.60 

4.80

 4.50

4 00

4.00 

4.20

Dee.

4.00 

4.10

4.20

4.10

4.00

4.00

3.90 

3.80

3.90

5.00 

5.50 

5.90

5.70 

5.80

8.90

8.20 

7.80

7 50

6.80 

6.10

5.60 

5.10

4.90

5 9fl

5.20 

5.00

5.30

5.10

6.30 

9.40

7.60

a Frozen.
PRESSEY.] GAGE HEIGHTS. 95

Mean daily gage height of Housatonic River at Gaylordsvitte, Conn., for 1902.

Day.

1 ..............

2

3. ...... ...

4. ...__..___...

5. ......... ....

6. ......."......

7....--.-....

8.... ________

9. _ .__ 

10..............

11..............

12

13- --.- 

14..............

15.----..---___.

16. .............

17........... 

-to

19. .--__-_____..

30

21

22

23... -

24... ______

25..-. ___.

26 __._

27- 

28

29..-. ____.._._ 

30.-.- ____-_...

31-- 

Jan.

7.10

6.50

5.90

5.30

E on

5.30

5.30

5.20

5.30

5.10

5.00

4 on

4. TO

430

4.50

i fin

4.30

4.20

4. 4|)

4.20

4.50

'8.50

6.80

6.30

5.80

5.60

5.90

5. TO

5.30 

4.90

4.90

Feb.

4.90

4.90

5.40

4.90

4 80

4.60

4.50

4.40

8.50

6.80

7.00

8.00

8.80

8.30

8.00

7.10

6.80

7.00

7 50

7.30

7 SO

7.20

6.80

6.50

6.80

7.00

10.60

9.00

Mar.

14.30

10.80

9.90

10.20

7:80

6.80

6.50

6.80

6.80

7.50

2 20

7.70

7.80

8.00

7.90

7.70

T.90

7.60

7.30

7.00

6.60

6.60

6.10

5.90

6.00

6.00

5.90

5.90

6.70 

6.70

6.70

Apr.

6.80

6.60

6.80

5.80

5.80

5.50

5.50

5.70

6.10

6.80

6.90

6.80

6.80

6.70

6.20

5.90

5.80

5.60

5.60

5.50

5.20

5 20

5.10

5.10

5.00

4.90

5.00

5.10

5.10 

6.20

May.

6.80

6.30

6.10

5.90

1 fiO

5.50

5.50

K on

5.20

4 90

5 no

4 90

4 90

4.80

4.70

4.60

4.60

4.50

4 40

4.30

4.60

4 40

4.30

4.10

4.20

i <ai

4.60

f. on

5.20 

5.00

4.70

June.

4,70

4.40

4.40

4.60

4 on

4.80

4.60

4.60

4 40

4.60

4 50

4.50

4 40

4.70

4 60

4.30

4.50

4 40

4 40

4 40

4.30

4.70

4.50

4.30

4 30

4.30

4.20

4.20

4.10 

4.30

July.

4.80

4.60

4.40

4.70

4.50

4.50

4 80

5.00

4.70

4.50

4.40

4.30

4 20

4.00

3.90

4.10

4 20

3.90

3.80

4.65

6.00

6.60

6.00

5.70

5.50

<. <¥.

4.95

4.85

5.55

5 45

5.40

Aug.

4.80

4.65

4.65

4.45

4.30

4.40

i tin

4.55

4.55

A AR

4. <a.

5.15

5.00

4.70

4.50

4.35

4.20

4 00

3 on

4.05

Q (K

4 05

4.10

4.10

3.95

 -* (K

 -* Qf.

3.95

3.90 

3.90

3.70

Sept.

3.80

3.55

3.50

3.60

3.65

3.55

3.65

3.50

3.55

4 00

4 00

3.90

3.85

4.10

4 00

3.60

3.70

a 75

3.80

3.85

4.05

3.60

3.70

3.65

3.85

4.30

4.60

6.30 

6.00

Oct.

5.50

5.50

5.25

5.15

5.00

5.15

5.00

4.85

4.70

4.55

4.40

5.30

5.30

5.10

5.00

4,80

4.75

4.60

4.55

4 25

4.30

4 45

4.40

4.45

4.45

4.40

4.30

5.85

6.55 

6.00

5.80

Nov.

5.50

5.30

5.00

4.95

4.85

4.75

4 65

4.60

4.50

4.35

4.30

4.45

4.40

4.50

4.50

4 40

4.35

4.25

4 30

4.25

4.30

4 20

4 20

4.05

4.15

4 25

4.60

4.50

4.40 

4 25

Dec.

4.10

4.15

4.40

4.60

4.60

4.30

4.35

4.30

3.45

3.55

3.70

3.75

4 00

4.05

4 25

4 90

7.90

7.35

6.70

6.35

6.65

8.60

8.40

7.55

7.30

6.90

6.65

6.00

5.'75 

5.90

5.60
96 FLOW OF EIVEES NEAE NEW YOEK CITY. [NO. TO. 

Current-meter discharge measurements of Catskill Greek at South Cairo, N. Y.

Date. G-age 

height.

1901.

Oct.lO-___-__._____ _______ .58

Oct. 4 __________________ .70

Nov. 8_____________________ .70

Aug. 19 ............ .70

Sept. 23 ____________________ .74

Nov. 9 _____________________ .75

July 4___ __________________ .75

Aug.l _____________________ .80

Oct. 22 _____________________ .82

Sept. 7_______________._._._! 2.92

Aug.9 ----._.__............' 3.00

July 35._ _________________ 3.00

Sept. 2 _____________________ 3.00

Aug. 27 -.--_...._._........ 3.12

July 17.____________________ 3.50

July 20.____________________ 3.60

June 13______._____________ 2.69

June 24-___.___............ 2.70

Aug. 27.................... 2.74

Sept. 5....__............... 2.79

JuneS _---.--.-.-.--.....-- 2.82

May 23_______._____..__..., 2.83

Sept. 22-------............. 3.32

July 9.___-..-.__-_-..-.-._._ 3.365

May 10__.____-_._..______._ 3.47

Aug. 13 ______..._._______.. 3.49

Nov. 7 ______-.___._..______ 3.80

Dec. 3.---.................. 3.90

Oct.10..................... 3.92

Apr.22..................... 4.06

Aug.'S-----..--.-.-----..-. 5.36

JulySS..--..-........._.... 6.11

Apr.ll..................... 6.86

Mar. 13 .................... 8.66

Discharge.

Second-feet, 

23.3 

25.6 

27.6 

39.6 

35.6 

42.3 

60.9 

47.9 

54.2 

68.8 

81.5 

81.9 

87

121.4 

260.3 

307.5 

40.6 

43.5 

39.4 

50 

49.5 

51.1 

121 

113.5 

133 

135 

235 

275 

242 

320.2 

1,005 

1,602 

2,312 

5,483

Hydrographer.

Hollister and Schlecht. 

W- W. Schlecht.

Do.

Hollister and Place. 

W. W. Schlecht.

Do.

Horton and Hollister. 

A. E. Place. 

W. W. Schlecht. 

A. E. Place.

Do.

Do.

Do.

Do.

Pressey and Place. 

A. E. Place. 

W. W. Schlecht.

Do. 

H. K. Barrows.

Do. 

W.W. Schlecht.

Do.

P. M. Churchill. 

H. K. Barrows. 

W. W. Schlecht. 

H. K. Barrows. 

F. H. Tillinghast.

Do.

P. M. Churchill. 

W. W. Schlecht. 

H. K. Barrows.

Do.

W.W. Schlecht. 

Horton and Schlecht.

A measurement made February 27,1902, with the stream obstructed 

by ice, showed the discharge 363 second-feet, gage height 4.72. The 

stream was frozen from bank to bank to a depth of 6 to 8 inches,
PRESSEY.] DISCHARGE MEASUREMENTS. 97 

Current-meter discharge measurements of Esopus Creek at Kingston, N. Y.

Date.

1901.

A n fy ^\

Tnlv 99

July 18. ....................

July 5 ............ .........

July 19.... .................

Nov. 18 ....................

Sept. 26 ....................

Do .....................

Aug. 19 ....................

Oct. 10.....................

Do.....................

Oct. 8......................

Nov. 1 .....................

Nov. 14 ....................

Sept. 21 ....................

Aug. 10.. ..................

Nov. 26 ................. ...

Oct. 3 ......................

Sept.'6 .....................

Aug. 39 ....................

Oct. 21.....................

Aug. 8 .....................

Sept. -i. .......... ..........

Aug. 27 ....................

Oct. 16.....................

Dec. 19. ...................

Dec. 11......... ............

Dec. 30. ....................

1902. 

June 16 ............ . .....

Sept. 4.... ........ .........

Aug.21 ....................

June 26 -....._.............

June o ...............

July 16.....................

Nov. 23 ....................

July9.. ....................

May 14... ..................

Sent, 33.............. ......

G-age 

height.

Feet. 

3.60

3.80

4.10

4.32

4.40

4.45

4.55

4. 55

4.60

4.62

4.62

4.70

4.74

4.75

4

f**Q

' 4. 85

5.06

5.26

5.46

5. 50

5.56

5.65

6.11

6.26

6.64

8.35

11.46

12.15

4.48

4.49

4.94*

5. 02

5.03

5.13

5.45

5.81

5.83

5.87

Discharge.

Second-feet. 

39.9

64.3

144.9

148

172.7

126. 5

167.8

150.4

180.2

165. 8

188.1

178.3

184. 3

195.4

200.3

259. 2

244.7

329. 4

352. 2

364. 3

380. 8

396.1

f**OO C

785. 2

1,472

1,720.8

3,989

135.8

133

191

225

334. 5

268.8

272

450. 4

423

449

Hydrographer.

A. E. Place.

Do.

Do.

Horton and Hollister.

A. E. Place.

W. W. Schlecht.

Do.

Do.

Hollister and Place.

W. W. Schlecht.

Geo. B. Hollister.

W. W. Schlecht.

Do.

Do.

Do. '

A. E. Place.

W. W. Schlecht

Do.

A. E. Place.

Do.

W. W. Schlecht.

A. E. Place.

Do.

Do.

W. W. Schlecht.

Do.

Do.

Do.

W. W. Schlecht.

H. K. Barrows.

Do.

W. W. Schlecht.

Do.

H. K. Barrows.

F. H. Tillinghast

Barrows and Schlecht.

W. W. Schlecht.

P. M. Churchill.

IRE 76 03-
"98 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. 76. 

Current-meter discharge measurements of Esopus Creek, etc. Continued.

Date.

1902. 

Nov. 11-... -.. -..-..-

Aug. 12 -------------.-.--..

May 24

June 5 ________________ _ _

Nov. 5 _____________________

Apr. 23 . . ......

IMay 14_ ______ ______________

July 30 _ _____________ __..

.July 34... __________________

 Oct. ^.. ....................

"Mar. 12. .___-____. _______

Apr. 30 --------------

Apr. 10 _______________ __ _

Mar. 1 _____._.___.___ ______

Gage 

height.

Feet. 

6

6.28

6.38

6.41

6.56

6.94

7.14

7.65

8.11

9 32

9. 90

10. 28

13. 37

20. 38

Discharge.

ftccnticl-f?et. 

416

550

"274

«273

594

828. 3

« 508

1,155

1,348

1,890

2, 843

2.813

5, 021

''12.620

Hydrographer.

.F.H.Tillinghast.

H. K. Barrows.

W. W. Schlecht.

Do.

F.H.Tillingliast.

W.W. Sehlecht.

Do.

H. K. Barrows.

Do.

P. M. Churchill.

W. W. Sehlecht.

Do.

Do.

« Measured at Glasgow Bridge, Glen Eyrie.

& Large quantities of floating ice in the stream. Surface velocities used.

The following measurements were also made during the period of 

ice obstruction by W. W. Sehlecht:

February 20: Gage height, 5.38; discharge, 245 second-feet; river 

partly "frozen over. February 15: Gage height, 5V60; discharge, 557 

second-feet; river mostly frozen over. February 7: Gage height, G.83; 

discharge, 530 second-feet; river partly frozen. September 29, 1.30 

p. m., the stream attained a flood stage, giving a reading of 25.25 011 

the gage.

Current-meter discharge measurements of Rondout Creek at Rosendale, N. Y.

Date.

' 1901. - 

July 18- ___._-----_-- _--_-.-

Aug. 6 ....__..---.---.--'---

Sept. 24 _____._____.._____,_

 Oct. 11 _____________________

Oct. 11_..__ ________ _______

:Nov. Ifi... .................

Julyfi-... ------------------

Oct. 7. _________ .....-------

Gage 

height.

feet. 

6.30

6.40

6.42

6.45

6.47

6.47

6. 55

6. 55

6.55

6.60

Discharge.

Rpcnnd-feet. 

118.2

99.4

138.2

139. 6

163.2

201.8

183

319

2°i5 4

217.5

Hydrographer.

A. E. Place.

Do.

W. W. Sehlecht

Do.

Do.

G.B.Hollister.

W. W. Sehlecht.

Horton and Hollister.

A. E. Place.

W.W.Schleclit.
PBBSSEY.] DISCHARGE MEASUREMENTS. 99 

Current-meter discharge measurements of Rondout Greek, etc. Continued.

Date.

1901. 

Sept 7.....................

A.US 20

Oct. 18.....................

A Tie- ^a

Aug. 8........ ...... !____..

Sept. 4........ .............

Dec. 21-------. --------

Sept. 3. .......___.__...--..

Dec. 12.. ...... ... .. ....

Nov. 26 _..---- - -

Dec.30. .......

1902. 

Sept. 25 ....................

July 15.. .......

July 18.-.----. ._......_.__.

Aug. 29 __________________ .

June 6 .....................

June 20 ....... ..___. ......

Nov. 21 ....... .

Dec. 2... ......._.....-.....

Apr.28.. ....... ------ ---.

May IS. ................

Nov. 4 _ ------ ... ...

Aug. 7.___. _____--.__..-__.

July29_--_ ..

Mar. 21 ........_..._.......

Mar. 1. ....... .

Apr. ll-______.

Gage 

height.

Feet. 

6.90

6.94

7.03

7.15

7.50

7.60

7.80

8

7.21

11.95

6.31

6.33

6.33

6.33

6.38

6.42

6.55

6.70

6.83

6.855

7.00

7.39

7.40

8.07

17. 60

11.78

Discharge.

Second-feet. 

426. 7

526. 4

509.9

644,6

745.4

836.1

t^^n

1.200

1,490.8

675.4

5, 353

167

141.9

137. 2

145

163

166

283.4

367

382

421

570

838

888

1,529

13, 936

5, 666

Hydrographer.

A. E. Place.

Hollister and Place.

W. W. Schlecht.

A. E. Place.

Do.

Do.

W.W. Schlecht. «

A. E. Place.

W. W. Schlecht.

Do.

Do.f'

B. M. Churchill.

Do.

Do.

W. W. Schlecht.

Do.

F. H. Tillinghast.

Do.

W. W. Schlecht.

Do.

F. H. Tillinghast.

H. K. Barrows.

Do.

W. W. Schlecht.

Do.

Do.

« Stream somewhat obstructed by shore ice.

Additional measurements were made by W. W. Schlecht while the 

river was frozen over, as follows:

February 18, gage height, 7.70; discharge, 342 second-feet. The 

river was frozen over from bank to bank and slush had collected 

below the iceFebruary 26, gage height, 8.13; discharge, 543 second-feet. Slush 

below the ice made an unsatisfactory record.

February 20, gage height, 8.43; discharge, 684 second-feet. Ice covered the river from bank to bank and slush had collected underneath.
100 FLOW OF KIVERS NEAK NEW YORK CITY.

The Delaware and Hudson Canal has beeA abandoned in New York 

State, with the exception of the portion from High Falls feeder on 

Bondout Creek to tide water, below Eddyville. The gaging station at 

Bosendale is situated opposite the canal level between locks 6 and 7. 

The water supply of this level is drawn entirely from Rondout Creek. 

In order to determine the amount of this diversion during the season 

of canal navigation, usually from April 1 to December 10, a record 

has been kept at lock No. 6, or Creek Locks, at the lower end of the 

Rosendale level. The record includes overflow at by-pass weir, water 

used for lockage, and flow through paddles in miter gates. There is 

also a small amount of leakage in the lock walls and gates which has 

not been determined. The flow in the canal at lock No. 6 added to 

the flow at the Rosendale station will give the total actual run-off 

from Rondout Creek above Rosendale. The following tables show 

the mean monthly and estimated daily diversion during the canal 

season of 1902. The estimated flow in the canal as recorded in 1901 

is as follows:

Second-feet. 

October, 1901..._________ ___________________________________________________ 20

November 21, 1901_________________.____-_--____--____-___---___.-__________ 19

Mean monthly diversion in second-feet to Delaware and Hudson Canal, lock No. 6,

near Rosendale, in 1902.

Second-feet

March« _________________________________________________________________ 15.70

April..................................................................... 22.45

May----------------..-----------...-.--....------------.................. 29.98

June ..--_---...---................................--...................- 23.67

July._--..._................_......_.........................._.......... 23.78

August---------.-.-.------------.---------.--,----------------------,---. 24.33

September._____________________________________________________________ 23.99

October _________________________________________________________________ 22.23

Current-meter measurements of Wattkill River at New Paltz, N. Y

Date.

1901. 

Nov.9---_---____-______-___

July23-_-._______. _________

Oct. 11-.-... -_.... ........

Oct. 11. ....................

Oct. 24......... ____________

6ct.9--..-.--... ..........

Nov. 16. ------- .............

JulyT..- ..... ._-__._

July 8.-. ..................

Gage 

height.

Feet. 

5.94

5.20

6.30

6.30

6.33

6.48

6.50

7.19

7.25

Discharge.

Second-feet. 

178

306

340

355

333

398

402

824

842

Hydrographer.

W.W.Schlecht.

A. ErPlace.

W. W. Schlecht.

Geo. B. Hollistei

W.W.Schlecht.

Do.

Do.

Horton and Hollister.

Do.

a March 23 to 31, inclusive.
PBESSEY.] DISCHAEQE MEASUREMENTS. 101 

Current-meter measurements of Wallkill River at Neiv Paltz, N. Y, Continued.

Date.

1901. 

Oct. I........ ..............

Nov.37........ .......__....

Sept. 19 .........i... ........

Aug. 13 ....................

July 19..... _..._...........

Sept. 5. ............... ....

Aug. 31 ....................

Aug. 20 -_-_.-__. _____1_.__,

Aug. 28 ....................

Dec. 11.....................

Dec. 19.... _ ________________

Aug. 7-_-____-__________--_

1902. 

July IT.-..-. --_-_-. __ __-

Aug. 28 .___-__________.._-_

Sept. 18 __________________ .

June 19 ______ _____ _

May 21. .

June 6 . . _-_._____.._-___.

Nov. 18___________. .......

May 13. --_-________.____._

Aug. 15 __ ..........

Dec. 2.--..-.. __ . _ i

Apr. 26 ___.___.,__.._.___._

Feb. 24__ __________________

July 29. ____________________

Apr. 21 _____:___._...____.

Feb. 10.. ............ ...

Nov. 4 _-____.. , . . _

Aug. 6.....................

Apr. 9 ...................

Mar. 11 _...._....... ....

Gage 

height.

Fet't. 

7.36

7.. 52

7.73

7.85

8.25

8.90

9.07

10.00

10.60

11.50

13. 70

14.85

5.70

5.86

5.96

6.18

6.83

6.40

6.62

6. 68

6.72

6.80

6.92

7.33

7.49

i* r-Q

7. 93

7.98

10, 264

13.21

15.93

Discharge.

Second-feet. 

896

1,022

1,076

1,038

1,243

1,676

1,917

2,729

2,982

3,040

3,277

7,365

124.3

169

209. 5

295

344

381

550

506

518

626

6680

288

' 942

c 1,028

597

1,165

1.150

2,623

5,354

7,140

Hydrographer.

W. W. Schlecht.

Do.

Horton, Place, and Schlecht.

A. E. Place.

Do.

Do.

Do.

Hollister and Place.

A. E. Place.

W. W. Schlecht.«

Do.«

A. E. Place.

H. K. Barrows.

Do.

Barrows and Churchill

W. W. Schlecht.

Do.

Do.

F. H. Tillinghast

W. W. Schlecht.

H. K. Barrows.

F. H. Tillinghast.

W. W. Schlecht.

Do.

H. K. Barrows.

W. W. Schlecht

Do.

F. H. Tillinghast.

H. K. Barrows.

W. W. Schlecht.

Do.

Do.

« Stream obstructed by ice causing backwater.

6 Measured through ice 1 foot 6 inches to 3 feet 6 inches in thickness.

^Measured through ice 1 foot to 2 feet in thickness.
102 FLOW OF RIVERS NEAR NEW YORK CITY. [NO. 76.

Current meter measurements, of FishkiU Creek, at Glenham, Dutchess County,

N. Y.

Date.

1901. 

July24__ ...... . ..

Oct. 13. ....................

Nov. 11 ... ______________

July 20....... _ _ .. ...

July 8__.____. __'_______.___

Nov. 20 _..__.....__._____..

Oct.5__________________ ...

Oct. 15_____. __..._ __ ..

Sent. 6________________^___.

Sept. 18_...._.. ............

Dec. 24_______ ..............

Aug. 21 ....................

Aug. 30 _______ __^ __ ____

Dec. 13. __________ ________

Oct. 15....... ._____. ______

Dec. 31. ____________ _______

1902. 

Aug. 26 __________________

Julyl4_________ ... _ ._

Aug. 11 ____________________

Oct. 11_______________ _____

July 28__. ._______._______..

June 17

Nov. 8 ____________ _______

Apr. 25. ____________________

May 6_______-________._____

Feb. 11. _._....._...._..._..

Oct. 30. _......_......_.....

Apr.l2____. ________________

Mar. 5 _____________________

Gage height

Feet. 

3.60

3.80

3.85

3.85

3.86

3.90

3.93

3.95

3.98

4.05

4.15

4.22

4.52

4.56

4.60

4.62

5.10

7.43

3.04

3.18

3.51

3.71

3. 785

3.90

4.00

4.00

4.03

4.46

4.87

4.97

5.30

5. 79

Discharge.

Second-feet. 

60

97

82

110

90

135

147

114

126

137

193

229

315

342

3?5

375

579

2 210

48.5

64.4

115

155

132. 3

200

212. 5

233

&152.4

349.5

C202.5

697. 7

772.6

1,129

Hydrographer.

A. E. Place.

Geo.B. Hollister.

W. W. Schlecht.

A. E. Place.

W. W. Schlecht.

A. E. Place.

Horton and Hollister.

W. W. Schlecht.

Do.

Do.

A. E. Place.

Do.

W. W. Schlecht.

A. E. Place.

Do.

W. W. Schlecht.

Do.

Do.«

H. K. Barrows.

Do.

Do.

P. M. Churchill.

W. W. Schlecht.

H. K. Barrows.

W. W. Schlecht.

F. H. TiUinghftst.

W. W. Schlecht.

Do.

Do.

C. O. Covert.

W. W. Schlecht.

Do.

a Surf ace velocity used. 

& Probably incorrect.

<^Ice along banks at gaging station, frozen from bank to bank GO yards below station 

9 inches thick.
DISCHARGE MEASUREMENTS. 103

Current-meter discharge measurements of Tenmile River at Tabor's bridge, below

Dover Plains, N. Y.

Date.

1901. 

Sept. 16..---....------.---.

Sept. 38---..-..-.....-.....

Nov. 11 ....................

Nov. 22 ..----......._......

Nov. 23 ....................

Nov. 6 _..___-______.____-_

Oct. 36.....................

Dec. 27-_______ .............

Oct. 15-...---...-.-........

Dec. I?.-.......-...... ....

1902, 

Sept. 3......... .... .....

Aug. 19 -,.. .. ... ... -...

June 10 . - . .. .___----____-___

Feb.l3.__ ....---..-...,....

Aug. 4 __________________ _

N0V.38----.-. .-___-.

Nov. 14-...-_. .....

May 15 .___._ _ _.!__________-

June 30 ---___-_-..__

May 28... .,

Oct. 3. .....................

Apr. 15 -__-____-_-_____. .

Apr. 7. -_._._.._.... , .-..

May 3 ________ _.....

July 31.. ........... -

Mar. 3.__

Q-age 

height. 

Feet.

5.27

4.36

4.75

4.76

4.76

4.88

5.01

6.54

7.19

8.41

3.95

4.28

4.45

4.67

4.69

4.80

4.87

4.88

4.92

5.50

5.80

6.13

6.18

6.46

7.18

10.41

Discharge.

Second-feet, 

245.4

70.3

121.5

123.4

120.9

140.1

187.6

554

692.8

1,213.4

63

100

«158

179

184.8

211.5

311

230

249

380

443

536

558

640

821

3, 386

Hydrographer.

A. E. Place.

W. W. Schlecht.

Do.

Do.

Do.

Do.

Do.

Do.

Do.

Do.

Do.

W.W. Schlecht

Do.

H. K. Barrows.

F. H. Tillinghast.

Do.

W.W. Schlecht.

Do.

Do.

P. M. Churchill.

W. W. Schlecht.

Do.

Do.

W.W. Schlecht.

« Eiver nearly covered with ice from bank to bank and li to 2i inches thick.
104 FLOW OF BIVEKS NEAB NEW YOEK CITY. [NO. 76. 

Current-meter discharge measurements ofHousaton ic River at Gaylordsville, Conn.

Date.

1900. 

Oct. SO....... _--__-----.--.

Oct. 24______..___ ...........

Aug. 10....................

A IIP- Q

1901. 

Aug. 3.... .................

Sept. 28 ....................

Sept. 13.. ..................

Oct. 2^. ....................

Nov. 23_... ................

Nov. 13. ...................

Dec. 38...._. ...............

1902. 

Sept. 8 .....................

Sept. 19 ....................

Aug. 20 _._._______._._._...

July 11.....................

Nov.29-_.-_____. ___________

June 23 .._____. _.._____._.

Nov. 15.. . ...............

Oct. 8 ......................

May 3-.-------.-..--.--.--.

July 32......... _-.---- --..-

Mar. 18..... ................

Gage 

height.

Feet. 

3

3.10

3.25

3.30

3.50

3.78

4

4.05

4.11

4.82

r>. 16

3.45

3.75

3.95

4.28

4.30

4.40

4.46

4.50

5. 35

6.10

6.68

7.63

9.9

Discharge.

Second-feet. 

303

370

422

450

549.5

700.8

911.7

951

965. 4

1,863.7

2, 250

543

640

835

983

1,159

1,381

1

-f r*j«j

1,3-56

2,133

4, 459

5, 119

8, 259

13. 601

Hydrographer.

E. G. Paul.

Do.

Do.

Do.

A. E. Place.

W. W. Schlecht.

A. E. Place.

W. W. Schlecht.

Do.

Do.

Do.

H. K. Barrows.

Barrows and Churchill.

H. K. Barrows.

Do.

Do.

F. H. Tillinghast.

W. W. Schlecht.

F. H. Tillinghast.

P. M. Churchill.

W. W. Schlecht.

H. K. Barrows.

W. W. Schlecht.

Do.
INDEX.

Page.

Abbott, H. L., and Humphreys, A. A., 

cited on form of vertical velocity curve..- .............. 33

reference to --_..............._._- 20,46

Alkalinity, method of determining. --.-.. 76 

of streams discussed, diagram showing ...'.......................... 76

table showing ._................. 77-85

Alien, C. J., work of ...................... 63

Austin, Tex., hydraulic plant at, failure

of............................... 10

Babb,C. C., reference to.................. 20

Bear Valley dam, California, lack of

water in ..........__........ 11

Birdsall, G, N., measurements suggested

by................- .......... 13

Catskill Creek, alkalinity observations on,

diagram showing results of... 76 

color observations on, diagram showing results of ........._...... 74

discharge measurements of...._.... 98

gage heights of ....................__ 87

gaging station on, description of._ _ 37-38 

view of-..........---.-.-.....-..... 36

liardness observations on, diagram

showing results of--..-..._--- 78 

quality of water of, table showing ... 77 

turbidity observations on, diagram

showing results of...... _. -.. 70

velocities in vertical sections on,

tables showing----.....---- 39-40,45

under ice, tables showing......... 58

velocity at mid depth and mean ve-

" locityon, relation bet wean - -.. 46 

vertical velocity carve for, diagram

showing-....,-...__-...-....- 24

Color, methods of determining..-----.... 73-76

of streams discussed, results of observations of, diagram showing.. 74 

table showing...................... 77-85

standards for determining............ 74-75

tubes and disks for determining plate

showing........ _...------_- 73

Cunningham, Allan, cited on velocity of

rod floats. _..-.------.-..-....-- 18

Current meter, plate showing__..._.__ 30

' use of, in determining velocity.--._ 19-20

view showing-.............----...- 18

Dams, use of,in determining velocity.--- 18-19 

Darcy, H.,formuladerived by........ 36

DeProny, work of . ... .......... 36

Discharge measurements, methods of

making, views of--.--._-.-_--_ 18 

tables of .............................. 96-104

Disks for measuring color of river

water ---......-..-.-..--...-.-. 72

Dover Plains, gaging station at, description of.......................... 29

Tenmile River at, discharge measurementsof____-..-...-.--.-.- 103 

gage heights of.................... 92-93

velocities in vertical sections on,

tables showing.--------_..-. 43,45

Bills, T. G., reference to--.--.-...-...---- 30,46

Bsopus Creek, alkalinity observations 

on, diagram showing results 

of............................ 76

color observations on, diagram show- -

ing results of ..._....._-..- 74

curves of equal velocity on, diagram

showing.._..._-----...---- 22

discharge measurements of.... 97-98 

gageheightsof--...-.. --....-- ---- 88

gaging station on, description of..... 28

view of.-._-__........__-... 26

hardness observations on, diagram

showing results of.......---.-. 78

quality of water of, table showing... 83-81 

turbidity observations on, diagram

showing result of.. ..... 70

velocities in vertical sections on, tables

showing ...I................ 32-34,45

under ice, table showing.... 54-55,63,64

velocity at mid depth and mean velocity on, relation between.... 46

vertical velocity curve for, diagram

showing-..........----....----. 24

under ice cover, diagram showIng ......................... . 61

Pishkill Creek, alkalinity observations 

on, diagram showing results 

of......................... r 76

color observations on, diagram showing results of .. .. __.... 74

discharge measurements of........... 102

gageheightsof ...................... 91-92

gaging station on, description of..... 28

hardness observations on, diagram

showing results of.......... 78

quality of water of, table showing ... 82-84 

turbidity observations on, diagram

showing result of.----.-__..--- 70

105
106 INDEX.

Page.

Fishkill Creek, velocities in vertical sections on, tables showing--. 41-43,45 

velocity at mid depth and mean velocity on, relation between.. - - 46 

vertical velocity curve for, diagram

showing ........I . .. 34

Floats, methods of using, to' datermine

velocity--....-----..----.-..... 15-18

Flow, estimates of, variation in --_-.._... 12 

Francis, J. B., cited on velocity ol rod

floats-..-...--............-.---- 17

formula for determining velocity by. 18 

reference to ..__..................... 19

Freeman, J. B., reference to..........._ 19

Fteley, A., and Stearns,F. P., reference to. 19 

Ga^e heights, tables showing-. - .... 87-95

Gaging stations, views of......._---..... 26,38

Gaylordsville, Conn., gaging station at,

description of-.----------.--.. 39

gaging station at, view of............. 38

Housatonic Eiver at, discharge measurementsof.--------- _......... 104

gage heights of... ................ 93-95

velocities in vertical ssetions on,

tablesshowing------------..... 44

Gila Bend, Ariz., failure of c'.am :vt-...... 11

Glenham, gaging station at, description

of............................... 38

Fishkill Creek at, discharge measurementsof ....................... 103

gage heights of.................... 91-93

velocities in vertical sections on,

tables showing ............. 41-43,45

Gordon, B., work of....-'-__..-__.....--- 36

Hardness, method of determining........ 76-77

of streams discussed, diagrams showing ............................. 78

tablesshowing __................ 77-85

Hazen, Alien, method of determining

color devised by._-.--..----.-- 73

Horizontal velocity curves on Wallkill

Eiver, diagram showing ------ 30

Housatonic Eiver, alkalinity observations on, diagram showing results of_-....---..-..-----_-...- 76

color observations on, diagram showing results of --.....--...___... 74

discharge measurements of _--..__.... 104

gage heightsof........................ 93-95

gaging station on, description of..... 39

view of............................. 38

hardness observations on, diagram

showing results of.. _ _-...... 78

quality of water of, table showing.... 84-85

turbidity observations on, diagram

showing results of.. ----------- 70

velocities in vertical sections on,

tablesshowing---...---.------ 44

velocity at mid depth and mean velocity on, relation between.... 46

vertical velocity curve for, diagram

showing------..----...-...- _-.. 34

Humphreys, A. A., and Abbott, H. L., 

cited on form of vertical velocity curve......-----...-..... 33

reference to........................__ 30,46

Ice, broken and tilted, flow of rivers

under ._......................* 64

smooth and unbroken, flow of rivers

under.......-...-....-.--.-.--- 48-64

Jackson, D. D., and Whipple, G. C., reference to...._..__......-.---. 71,73

Jellys Ferry, Cal., Sacramento Eiver at, 

relation of mean and surface 

velocity on...__... ----,... 23

Kingston, gaging station at, description

of............................... 28

gaging station at, view of.......--._ 36

Esopus Creek at, curves of equal velocity on, diagram showing... 22 

discharge measurements of._-.... 97-98

gage heights of ______-----_- -.-- 88

velocities in vertical sections on,

tableshowing............ 32-34,45

Lagrange, Cal., Tuoluinne Eiver at, relation of mean and surface velocity on .-_...---....-.-_.... 33

Lippincott, J. B., quoted on velocity 

curves on rivers in southern 

California......-.....--.--- 33

Measurements, method of making, views

of..-. . ..... .... ....... 18

Meter. See Current meter.

Mississippi Eiver, vertical velocity curve

on, form of........ -....... 33-23

Murphy, E. C., reference to -.....--...--- 30

New Paltz, gaging station at, description

of.. -.-.... .-. 28

gaging station at, view of--------.. 36

Wallkill Eiver at, curves of equal velocity on, diagram showing--- 30 

discharge measurements of. _.. - 100-101 

gage heights of ...........-.-. 90-91

horizontal velocity curves on, diagram showing .-.......-_.--- 30

ice cover and curves of equal velocity on, diagram showing. _ _ 48 

velocities in vertical sections on,

tables showing....-------... 37-38,45

New York City, gaging stations near.... 13

water supply of, proposed sources of- 13-13 

Newell, F. H., letter of transmittal by... 1 

Place, A. E., work in-, harge of. ..... . 2"

Platinum-cobalt method of measuring

color, description of..--_-._--. 73-76 

Platinum-wire process for determining 

turbidity, method of application of . .__ -.......... ------ 69-73

Powell, A. O., work of.......-. ...... 63

Price electric current meter, plate showing _..___....._.___ _ _.- 20

Quality of river water, discussion of.... - 67-88

Rafter, G.W., reference to... . 19 

Eiver channels, velocity in, methods of

measuring _-.,- -- -_..------ 14-20

Eod floats, method of using, to determine

velocity._--.._--...--...----- 17-18

Eondout Creek, alkalinity observations

on,diagramshowingresultsof- 76 

color observations on, diagram showingresultsof .............. 74

discharge measurements of-.-...-.-. 98-100
INDEX. 107

Rondout Creek, gage heights of ...... _ 89

gaging station on, view and description of.......................... 38

hardness observations on, diagram

showing results of............. 78

quality of water of, table showing.... 78-80

turbidity observations on, diagram

showing results of..---....._ 70

velocities in vertical sections on, tables showing................ 35-36,45

under ice, tables showing... 56-57,63,64 

under ice broken and tilted, tables

showing........................ 66,67

velocity at mid depth and mean velocity on, relation between... 46 

vertical velocity curve for, diagram

showing........................ 24

under ice cover, diagram showing 61 

Rosendale, gaging station at, view and

description of.............._ 38

Rondout Creek at, discharge measurements of ...................... 98-100

gage heights of .................... 89

velocities in vertical sections on,

tables showing.............. 35-38,45

Rough bed, effect of, on velocities in verticalsections................... 46-47

Sacramento River, California, relation of

mean and surface velocity on. 23 

San Gabriel River, California, relation of

mean and surface velocity on. 24 

L'anta Ana River, California, relation of

surface and mean velocity on. 24 

Schlecht, W. W., work in charge of...... 37

Smooth bed, effect of, on velocities in

vertical sections............... 48-47

South Cairo, Catskill Creek at, discharge

measurements of-......-..-... 86

Catskill Creek at, gage heights of.... 87

velocities in vertical sections on,

tables showing ............. 39-40,45

gaging station at, description of ..... 37-38

view of.............................. 26

Stearns, P. P., cited on surface velocity.. 21 

Stearns, P. P., and Pteley, A:, reference

to .............................. 19

Subsui-face floats, method of using, to

determine velocity... _... _ 16-17 

Surface floats, methods of using, to determine velocity"..._........ 15-16

Sweetwater reservoir, California, lack

of water in.._.............. 10

Tenmile River, alkalinity observations 

on, diagram showing results 

of............................... 76

color observations on, diagram showing results of--....---...-..... 74

discharge measurements of .......... 103

gage heights of........................ 93-93

gaging station on, description of..... 29

hardness observations on, diagram

showing results of.. __.. _ 78 

quality of water of, table showing... 82 

turbidity observations on, diagram

showing results of ..___.... 70

Page.

Tenmile River, velocities in vertical sections on, tables showing... 43,45 

velocity at mid depth and mean velocity on, relation between... 48 

vertical velocity curve for, diagram

showing ------.....-....--.- 24

Tube floats, methods of using to determine velocity..._--.....__ 17-18

Tubes for determining color, method of

fillingand holding ............ 75

plate showing -.....-..-..---.-..-. 72

Tuolumne River, California, relation of

mean antl surface velocity on.. 23 

Turbid water, color of, method of determining --...----...___--.-----.- 75

Turbidity, determination of.............. 68-73

of streams discussed, diagram showing result of------------------- 70

tables showing .---.-._._...... 77-85

platinum-wire process for det3rmining, method of application of. 69-73 

standard of............................ 69

stick for determining, view of...-.-.- 86 

Velocities in vertical sections, tables showing ............................. 32-47

Velocity in river channels, methods of

* measuring...._ ._.._.... 14-30"

point of mean, depth from surface to. 20-21 

relation of mean to mid depth.....-.- 46

to surface...--.-----..-- --. 23-26

Velocity curves, horizontal, on Wallkill

River, diagram showing ...... 80

Velocity curves, vertical, description of,

on streams without ice cover. 20-47 

diagram showing.....-.,..---... --.... 24

form of ................................ 22-23

Vernon-Harcourt, L. P., cited on relation

of mean to vertical velocity .. 2& 

Vertical sections, velocities in, tables

showing........-- -..-.. 33-47

Vertical velocity, relation of mean to surface ............................ 23-26

Vertical velocity curves, description of,

on streams without ice cover. 30-47 

diagram showing....--.--......-.--.-- 24

form of _..-......--.._..--...- ... 32-28

stations for obtaining ..._--...-...- 37-2& 

Wallkill River, alkalinity observations 

on, diagram showing results 

of............................... 76-

color observations on, diagram showingresultsof ....__---------- 74

discharge measurements of -------- 103-101

equal velocity curves on, diagram

showing-------.----.---..------ 80>

gage heights of ........................ 90-91

gaging station on, description of..... 28

view of............................. 2ft

hardness observations OB, diagram

show ing results of.----...-.... 78

horizontal velocity curves on. diagram showing..--..--.--...... 30

ice cover and curves of equal velocity

on, diagram showing.......... 48

quality of water of, table showing... 81-82;
108 INDEX.

Page. 

"Wallkill River, turbidity observations on,

diagram showing results of... 70 

velocities in vertical sections on,

tables showing---------_ 37-38,45

under ice, tables showing... 50-53,63,64 

under iee, broken andtilted, tables

showing.________________. 65,67

velocity at mid depth and mean velocity on, relation between - -. - 46 

vertical velocity curve for, diagram

showing..... _-...-....,.... 24

Paga

Wallkill River, vertical velocity curve 

for, with ice cover, diagram 

showing---..-.-----._-.-----. 60,61 

Warm Springs, Cal., Santa Ana River 

at, relation of surface and 

mean velocity on...----.---... 24 

Water powers, value and utilization of -. 9-10 

Weirs, use of, in determining velocity _-- 18-19 

Whipple, Gr. C., color disks rated by . __ 74 

Whipple, Gr. C., and Jackson, D. D.,

reference to ...... .---..--.. 71,72

o
LIBRARY CATALOGUE SLIPS.

[Take this leaf out and paste the separated titles upon three of your catalogue, 

cards. The first and second titles need no addition; over the third write that 

subject under which you would place the book in your library.]

United. States. Department of the interior. (U. S. geological 

survey.)

Water-Supply and Irrigation Paper No. 76 Series L, Quality 

of water, 4; Series M, Methods of hydrographic investigation, 

3 | Department of the interior | United States geological survey | Charles D. Walcott, director | j Observations on the 

flow of rivers | in the | vicinity of New York City | by | Henry 

Albert Pressey | [Vignette] | 

Washington | government printing office | 1803

8°. 108pp., 13 pis.

Pressey (Henry Albert).

Water-Supply and Irrigation Paper No. 76 Series L, Quality 

of water, 4; Series M, Methods of hydrographie investigation, 

3 | Department of the interior | United States geological stirvey | Charles D. Walcott, director [ | Observations on the 

flow of rivers | in the | vicinity of New York City | by | Henry 

Albert Pressey | [Vignette] |

Washington | government printing office | 1903

8°. 108 pp., 13 pis.

Water-Supply and Irrigation Paper No. 76 Series L, Quality 

of water, 4; Series M, Methods of hydrographic investigation, 

3 | Department of the interior United States geological survey | Charles D. Walcott, director | | Observations on the 

flow of rivers | in the | vicinity of New York City | by | Henry 

Albert Pressey | [Vignette] |

Washington | government printing office | 1903

8°. 108 pp., 13 pis.
SERIES L QUALITY OF WATER.

[See last page of this cover.]

SERIES M METHODS OP HYDROGRAPHIC INVESTIGATION. 

[See last page of this cover.] 

SERIES N WATER POWER.

WS 24. Water resources of the State of New York, Part I, by George W. Rafter. 1899. 92 pp.

13 pis.

WS 25. Water resources of the State of New York, Part II, by G. W. Rafter, 100-200 pp., 12 pis. 

WS 44. Profiles of rivers, by Henry Gannett. 1901. 100 pp., 11 pis. 

WS 62. Hydrography of the Southern Appalachian Mountain region, Part I, by H. A. Pressey.

1902. 95pp., 25 pis. 

WS 63. Hydrography of the Southern Appalachian Mountain region, Part II, by H. A. Pressey.

1902. 96-190 pp., 2^44 pis. 

WS 69. Water powers of the State of Maine, by H. A. Pressey. 1902. 124 pp., 14 pis.

SERIES O UNDERGROUND WATERS.

WS 4. A reconnaissance in southeastern Washington, by Israel C. Russell. 1897. 96 pp., 7 pis. 

WS 6. Underground waters of south western Kansas, by Erasmus Ha worth. 1897. 65 pp., 12 pis. 

WS 7. Seepage waters of northern Utah, by Samuel Fortier. 1897. 50 pp., 3 pis. 

WS 12. Underground waters of southeastern Nebraska, by Nelson H. Darton. 1898. 56 pp.,

21 pis.

WS 21. Wells of northern Indiana, by Frank Leverett. 1899. 82 pp., 2 pis. 

WS 26. Wells of southern Indiana (continuation of No. 21), by Frank Leverett. 1899. 64 pp. 

WS 30. Water resources of the lower peninsula of Michigan, by A. C. Lane. 1899. 97 pp., 7 pis. 

WS 31. Lower Michigan mineral waters, by A. C. Lane. 1899. 97 pp., 4 pis. 

WS 34. Geology and water resources of a portion of southeastern South Dakota, by James

Edward Todd. 1900. 34pp., 19 pis. 

WS 53. Geology and water resources of Nez Perces County, Idaho, Part I, by I. C. Russell.

1901. 86 pp. ,10 pis. 

WS 54. Geology and water resources- of Nez Perces County, Idaho, Part II, by I. C. Russell.

1901. 87-141 pp. 

WS 55. Geology and water resources of a portion of Yakima County, Wash., by G. O. Smith.

1901. 68 pp., 7 pis. 

WS 57. Preliminary list of deep borings in the United States, Part I, by N. H. Darton. 1902.

60pp. 

WS 59. Development and application of water in southern California, Part I, by J. B. Lippincott. 1902. flSpp., llpls. 

WS 60. Development and application of water in southern California, Part II, by J. B. Lippincott. 96-140 pp. 

WS 61. Preliminary list of deep borings in the United States, Part II, by N. H. Darton. 1902.

67pp.

WS 67. The motions of underground waters, by C. S. Slichter. 1902. 106 pp., 8 pis. 

B199. Geology and water resources of the Snake River Plains of Idaho, by I. C. Russell.

1902. 192pp., 25 pis.

The following papers also relate to this subject: Underground waters of Arkansas Valley in 

eastern Colorado, by G. K. Gilbert, in Seventeenth Annual, Part II; Preliminary report on artesian waters of a portion of the Dakotas, by N. H. Darton, in Seventeenth Annual, Part II; Water 

resources of Illinois, by Frank Leverett, in Seventeenth Annual, Part II; Water resources of 

Indiana and Ohio, by Frank Leverett, in Eighteenth Annual, Part IV; New developments in 

well boring and irrigation in eastern South Dakota, by N. H. Darton, in Eighteenth Annual, 

Part IV; Bock waters of Ohio, by Edward Orton, in Nineteenth Annual, Part IV; Artesian well 

prospects in the Atlantic Coastal Plain region, by N. H. Darton, Bulletin No. 138.

SERIES P HYDROGRAPHIC PROGRESS REPORTS.

Progress reports may be found in the following publications: For 1888-89, Tenth Annual, 

Part II; for 1889-90, Eleventh Annual, Part II; for 1890-91, Twelfth Annual, Part II; 1891-92, 

Thirteenth Annual, Part in; for 1893 and 1894, Bulletin No.131; for 1895, Bulletin No. 140; for 1896, 

Eighteenth Anjual, Part IV, WS 11; for 1897, Nineteenth Annual, Part IV, WS 15,16; for 1898, 

Twentieth Annual, Part IV, WS 27, 28; for 1899, Twenty-first Annual, Part IV, WS 35-39; for 

1900, Twenty-second Annual, Part IV, WS 47-62; for 1901, WS 65, 66, 75.

IRR 76 3
PAPERS OF SERIES L AND M.

SERIES L QUALITY OF WATER.

WS 3. Sewage irrigation, by George W. Rafter. 1897. 100 pp., 4 pis. 

WS 22. Sewage irrigation, Part II, by-George W. Rafter. 1899. 100pp., 7 pis. 

WS 72. Water pollution of metropolitan areas, by M. O. Leighton. 1902. 75 pp., 8 pis. 

WS 76. Observations on the flow of rivers in the vicinity of New York City, by H. A. Pressey. 

1902. pp., 13 pis.

SERIES M METHODS or HYDROGBAPHIC INVESTIGATION.

WS 56. Methods of stream measurement. 1901. 51pp., 12 pis. 

WS 64. Accuracy of stream measurements, by E. C. Murphy. 1902. 99 pp., 4 pis. 

WS 76. Observations on the flow of rivers in the vicinity of New York City, by H. A. Pressey. 

1902. pp., 13 pis.

IRE 76 4