FLOOD07044

• County: Statewide
• Community: State
• Stream Name: All
• Basin: Statewide
• Title: Floods in Colorado
• Date: 1/1/1948
• Prepared For: State of Colorado
• Prepared By: USGS
• Floodplain - Doc Type: Educational/Technical/Reference Information

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CONTENTS

Major lIood&-CoDtlnUed.
Ark_ RlV...-cODtlnUed.
lIuerfaoo Rlver..__...._......._______.___________________
ApbUuopaRlver._.____._____.__.__...._.._..___________.._
PurgataaeRlver_________________.________.____._.________
Wolf Creek and Granada Creek_.______________________.__..
~Bu~te C>.ek._____..______.______________.__.____.___.
Wildllorse ~ek_____________.____.__________._____..____
Minor tributaries of Arkansas Riveru_______________uu____
lUa Grande___________________________________________________
Sou~hFork RIo Grande__.....______________.______________
Al&D008a~ek.______.__.......__._..________._...._._.___
Conejos FUver____________________________________________
Colorado River ____ _ _ _ __ ____ ___ _ __ __ __ __ _ _ _ _ _ _ _ _ _ _ _ ___ _ _ _ _ _ _ ___
Gunn~on River___________________________________________
lJncotnpa~ River___________________________________
])olores FUver_____________________________________________
W..~ Creek..___......._..__.___.____..._._.__________
San Miguel River~ _ _ __________________________________
SanJuan FUver___________________________________________
Animas Fliver_________________________________________
La Pl&ta River________________________________________
Summary of maximum 69Qd discharges______________________________
Changes in channel capacity and development of flood-protection measures
Index____________________________________________________________

ILLUSTRATIONS

PLA.T8 1. City of Denver during the flood of May 19-20, 1864_ _________
2. Damage to Denver &; Rio Grande Railroad caused by flood of
June 1921: A, Bridge w..~ of Pueblo; B, Railroad yards in
Puehlo..............._._........._._....._______......
3. Damage to tracks of Denver &; Rio Grande Railroad caused by
flood of October 1911 on San Juan River near PagosaJunction_
l'IotJU 1. Map of Colorado showing principal river systems and cities
mentioned in the text_______________n_________________
2. Typical stage hydrographs of cloudburst floods_ _ _ _ _ _ _ _ _ _ _ _ __
3. Chart showing maximum flood discharge. in eecond.feet per
square mile, for various places given in the summary table__

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98
99
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112
112
113
114
120
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123
128
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138
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140
148
149

FLOODS IN COLORADO

By ROBIllRT FOLLANSBIllIll AND LEON R. SA WYIllR

ABS'l'R.LCT

The firo~ records of floods in Colorado aDtedated ~he ..~tlemen~ of ~he ,
by about 30 years. These were records of floods on the Arkansas and Repu
Rivers in 1826. Other floods noted by traders, hunters and emigrants,
of whom were on their way to the Far West, ocourred in 1844 on the ArH
River, and by inference on the South Platte River. Other early floods were
on the Purgatoire, the Lower Arkansas, and the San Juan Rivers about
The most serious flood since settlement began was that on the Arkansas
during June 1921, which caused the 1088 of about 100 lives and an e8th
property 1088 of $19,000,000. Many floods of lesser magnitude have Qce
and some of these have caused loBS of life and very considerable property da
Topography is the chief factor in determining the location of storms a1
suIting floods. These occur most frequently on the eastern slope of the
Range. In the mountains farther west precipitation is insufficient to ca.use
except during periods of melting snow, in June. In the southwestern pa.rt
State, where precipitation during periods of melting snow is insufficient to
floods, the severest floods yet experienced resulted from heavy rains in SeptA
1909 aDd Oc~ober 1911,
In the eastern foothills region, usua.lly below an altitude of about 7,50
and extending for a distance of about 50 miles east of the mountains, is a
8ubject to rainfalls of great intensity known as cloudbursts. . These cloudl
are of short duration and are confined to very small areas. At times the intA
is so great as to make breathing difficult for those exposed to a storm. The
of intenae rainfall are so small that Weather Bureau precipitation statioIlB
not been located in them. Local residents, being cloudburst conscious, freql
measure the rainfall in receptacles in their yards, and such records constitu
only source of information regarding the intensity.
A flood resulting from a eloudburst rises so quickly that it is usually des(
as a llwall of water." It has a peak duration of only a few minutes, follow
a rapid subsidence. Nearly 90 cloudburst floods in Colorado are deseril:
varying detail in this report. The earliest recorded cloudburst-called a1
time a waterspout---occurred in Golden Gate Gulch. July 14, 1872. The Il~
water" was described as a "perpendicular breast of 10 or 12 feet." A cloud
fiood on Kiowa Creek in May 1878 caused the 1088 of a standard-gage locom
and although search was made by means of long metallic rods, the loeomotiv
never recovered, as bedrock was about 50 feet below the creek bed.
All available information relative to floods in Colorado, beginning wit
flood of 1826 on the Arkansas River, is presented in this report, although for
of the earlier floods estimates of discharge are lacking.
Floods throughou~ a 1&rge part of ~he State have oceurred in 1844, JUDe
June 1884, May 1894, and June 1921. The highest floods of record were (l

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84

85

140

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141