Hot Springs weekly star. (Hot Springs, S.D.) 1892-1917, 1914-03-06
STATE ENGINEER DERR'S REPORT
GIVES FACTS and FIGURES.
PRACTICAL and FEASIBLE
OFFICIAL REPORT on ANCoSTuRA
PROJECT SHOWING COST, ACREAGE
and OTHER INTERESTING DATA.

In January, when State Engineer
Homer NJ. Derr came to Hot Springs
upon business concerning the Angos.
tura irrigation project. and to obtain
photographs OF the big reservoir and
other scenes in connection with the
project, he gave out his official report
as the result of the survey which had
been made during the summer under
his direction, by authority OF the lsgis.
lature. This report 10 herewith given
In full, showing cost, acreage and other
interesting, valuable data.
Angostura Project
Location.
Counties: Fall River and Custer. Town.
ships $ to 9 South. Ranges to East
Black Hills Meridian,
Railroads: Chicago & Northwestern;
Chicago. Burlington & Quincy.
Towns and Railroad Stations: Buffalo
Gap. 2so: Cascade P. O.: Edgemont.
s16: Hot Springs. 2.14o; Mohler, P. o.:
Oral, IS; Smithwick. IS.
Water Supply
Source of Supply: Cheyenne river.
Area of Drainage Basin (Edgemont). 1880
square miles.
Maximum recorded flow (Edgemont July
1905, 1o,96o second feet.
Minimum recorded flow (EdgemonN 90
second.feet.
Maximum recorded run.off for year
(Edgemont) 321 1000 acre.feet.
Minimum recorded run-oh for a year
(Edgemont) l47. 900 acre feet
Estimated mean available run-off at dam
site. $4,000 acre-feet or about o.45
inch for the entire watershed.
Data for Complete Project Reservoir
Survey.
High water contour survey. elevation.
334o feet; high water contour, (effective)
elevation 1900 feet; outlet gates. elevation.
326o feet; bed of river at dam, elevation.
316o feet; top of dam. (eaective) elevation,
1916 feet; length of surveyed high water
line, 90 miles.
Area OF reservoir at outlet, elevation
32oo, 324o.2 acres; area of reservoir at
effective high water line. elevation 5000,
5385.z acres: area of reservoir at surveyed
high water line. elevation 334o. oor3
acres.
Capacity below outlet, elevation 326o
1os.1 1o7 acre.feet: available capacity be.
tween elevation 326o and 5000. 164. .o65
acre.feet: grand total capacity as surveyed
up to elevation 334o, 567,711 aere.feet.
Dam is to be of rock-fill type: III slope
on the water side and 1:1H on the down
stream side: reinforced concrete facing u
to ~ feet thick over the entire water sur.
face.
Canyon is 200 feet wide at bottom and
go feet wide at the top of the dam. eleva.
ton 1916.
Maximum height of dam. 156 feet, max
imum thickness of dam 3o6 feet.
Canal Systems.
Length of North canal from Aneosturs
Dam to Badlands. 50 miles,
Important Structures: 11.7oo feet o1
fumes; 5000 feet of tunnels,
Typical dimensions lin earth) of canal
Bottom width. 1s feet, water line width
36.75 feet; depth rs feet.
Side slopes ,:1 lin cut) and 1:.k lin fill.
A-2o5.a square feet; R-4.s7; N
o225: So. oooz5; FL $40 feet per mile
Q-6lo second.feet.
Length of South Canal from Aneostur;
dam to Hay Canyon. 81 miles.
Important Structures: 1000 feet O
tunnels. 7.7oo feet of siphons. GOO feet o
fumes.
Typical dimensions in earth: Bottom
Width, 1S feet: water line width. 34.s feet
side slopes, III lin cut) and 1:1H lin fill.
A-173.25 square feet: R-4 41: N
o.oz25: S-o.ooo3: F-1.5s4 feet per mile
v-3.o9 feet per second; Q-5s4 secon,
feet.
Agricultural and Climatic Condition.
Total area included under North Canal
66.7z5 acres.
Area of good land susceptible Of irriea
ton. 53.o5o acres.
Total area included under South Cana
1896 acres.
Area of good land susceptible Of irriga
ton. 4o.685 acres.
Area under squaw Humper extension Q
South Canal, II, 500 acres.
Area of good land susceptible of irriRa
tion. $500 acres.
Total area Of good Land under bot, mai