FLOOD00269

• County: Statewide
• Title: Colorado Flood Hydrology Manual Draft Version 2.0
• Date: 1/1/1995
• Prepared For: CWCB
• Prepared By: US Army Corps of Engineers
• Floodplain - Doc Type: Educational/Technical/Reference Information

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not extend to thB upper river, as the Pueblo gaging station showed a maximum of only
3,080 cfs on July 21. The rainfall was apparently heaviest in the vicinity of Las Animas
and LaJunta. At the former place the rainfall was 3.36 inches July 24-25, and 4.66 inches
for the month, or more than twice the normal. At Pueblo the rainfall for July was only 0.39
inch.

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Flood of 1889. Rains on August 9, 1889. were followed by a flood that caused
overflow from Grape Creek at least as far east as Pueblo. These rains must have been
of the cloudburst type in the Arkansas Valley. as at none of the rainfall stations was the
recorded precipitation heavy except at Pueblo, where 1.02 inches of rain in 1 hour on
August 9 was recorded. This intense rainfall, with a temperature of 98 degrees before the
storm, indicates a cloudburst. From the account of the Grape Creek flood it appears that
the flood on the Arkansas River came primarily from that source. It was evidently
augmented by rain at other points. The Denver Republican states that rain began falling
about 5:30 pm on August 9, and flooded the region around Pueblo, and that a 'erriblB and
disastrous rainstorm visited Florence in the evening and lasted 2 hours. The Denver & Rio
Grande is having lots of trouble caused by the cloudburst of Friday night. The
Hardscrabble bridge washed out"

Flood of 1893. In 1893, one of the driest years of record at Pueblo, a flood
occurred on July 26, which reached a stage 10 feet lower than that of the flood of 1921.
The river rose 8 feet in 2 hours at Pueblo. No gaging station record of the discharge is
available, but from the rating curve established for thB flood of 1921, with an allowance for
channel clearance made after the flood of 1893. it appears that the peak discharge was
between 20,000 and 25,000 cfs.

Flood of 1894. The local newspaper on the evening of May 30, 1894, reported
that at Salida rain had fallen continuously for 36 hours and was continuing and that for the
duration and volume the storm exceeded anything in the memory of the oldest inhabitant.
At the same time, Florence reported that rain had fallen there for the preceding 24 hours
and that the amount was estimated at 3 to 4 inches. The precipitation above Canon City
had little influence on the ensuing flood, as the discharge at Canon City was not greatly
in excess of that during years of heavy mountain snowfall. In the Arkansas Valley above
Pueblo this flood reached a higher stage than the flood of 1921. Below Pueblo, however,
it was considerably lower. At Las Animas, according to the Bent County Democrat of June
8,1921, the flood of 1894 reached First Street, whereas the flood of 1921 was 4 feet deep
at that point. The city engineer of Pueblo subsequently made a slope-area determination
of peak discharge and found it to be 39,100 cfs. Subsequently the channel capacity
through Pueblo was increased to 40,000 cfs.

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Flood of 1904. The Purgatoire River flood of September 29-30, 1904, caused a
flood in the lower part of the Arkansas Valley in Colorado. No gaging station was in
operation at that time at the mouth of the Purgatoire River, and it is therefore impossible
to determine the volume of the flood entering the Arkansas River. It is believed, however,
to have been at least as great as the peak discharge of 44,300 cfs at Trinidad. Rainfall
in the Arkansas River Basin below the Purgatoire River undoubtedly increased the flood
volume in the Arkansas River. At the Colorado and Kansas diversion dam, 3 miles west

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Colorado Flood
Hydrology Macnilalc

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