FLOOD00051

• County: Pueblo
• Title: The Arkansas River Flood of June 3-5, 1921
• Date: 2/5/1996
• Prepared For: Pueblo County
• Floodplain - Doc Type: Flood Documentation Report

16 THE ARKANSAS RlVER..:I'LOOD OF JUNE 3-5, 1921.

.
The statements of local residents and the measured maximum dis-
charges of the tributary streams indicate two principal areas of
intense rainfall. (See PI. 1.) The larger area, which is roughly ellip-
tical, extends from the northern boundary of Pueblo County to the
top of the 'Vet Mountains near Beulah, a distance of 30 miles, and
from a point a short distance above the mouth of Rush Creek nearly
to Pueblo, a distance of 15 miles. The smaller area covers the south
slope of the Pikes Peak uplift, which forms the northern part of
the monntain valley, and extends from a point above Skaguay reser-
voir to a point 3 or 4 miles south of the river, a distance of 25 miles,
and from Oil Creek to Beaver Creek, a distance of 11 miles. The two
a.reas cover 559 square miles.

EFFECT OF RESERVOIRS ON THE FLOOD.

Consillerahle misinformation rebli,e to t1w ('IIeet of reservoirs
npon the flootl was di5:;cminated hy the g~ner:l\ 'and lechnical [It'c~'i
at the time of its OC"IIITl'/JCI'. Thet'e arc three rc~crvoirs of con-
siderable size within the areas () r intens(' rainfall, amI lione of these
contributetl to the main flood 0 f .J llne 3. The Schaeffer reservoir,
on Beaver Creek, biled on June 5, causing the flood of that date,
which was very severe in the valley immediately below the mouth of .
Beaver Creek but flattened (mt farther llownstream. The other two
reservoirs, the Skagnay reseryoir, on Beaver Creek, and the Teller
reservoir, on Turkey Creek, safely withstood the flood. At the time
of the main flood the three reservoirs helped in a slight degree to
reduce its magnitude by holding back a portion of the run-off a.bove
them.
The Schaeffer reservoir, which had a capacity of 3,190 acre-feet,
was formed by an earth dam across Beaver Creek in sec. 9, T. 18 S.,
R. 68 W. The dam had a maximum height of 100 feet above the
bottom of the outlet and a length on the crest of 1,100 feet. ;Its
average height was about 90 feet for the middle 500 feet of' its
length. The width on the crest was .15 feet, the outside slope 2 to 1,
.' and the inside slope 3 to 1. A freeboard of 10 feet was provided.
. A concrete cut-off wall was provided in the micldle portion of the
dam, and a timber cut-off wall for the remainder. The inlet was a
concrete tunnel '4 feet ,,-ide ,1 nd 5 feet high, constructed on bedrock.
The dam was built to a height of 21) to 30 feet by the hydraulic-
fill method when it waS o\>sern'd that the lll:tterial deposited in the
center of the dum retained water and dillllot cOllsolidate, being more
nearly liquid than solid. The liquid material "as replaced by dry
earth, and the dam was finisherl by depositing the earth by wagons,
sprinkling, and rolling in thin layers. The inner slope was rip-
rapped to the top. A spillway 100 feet wide was provided beyond