FLOOD04959

• County: Garfield
• Community: Rifle
• Stream Name: Rifle Creek
• Basin: Colorado Mainstem
• Title: City of Rifle Flood Hazard Mitigation Plan - The May 15, 1993 Flood
• Date: 9/1/1993
• Prepared For: Rifle
• Prepared By: Rifle, Colorado Office of Emergency Management
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

City of Rifle Flood Hazard Mitigation Plan

burst activity with high-intensity rainfall of
short duration during the summer and fall
months. Average annual temperatures vary
from less than 32 degrees F in the high head-
water areas to approximately 50 degrees F in the
lower valleys.

Rifle Creek Flood History

The Rifle Creek basin has a long history of flood-
ing. Damage from flooding has been incurred
several times since Rifle was settled. Despite
this flood-prone history, data for specific flood
events is poor. This is due mainly to the lack of
stream gauges in the area. Ai; a result, historic
flood information has been pieced together
mainly from newspaper accounts. From avail-
able information, it can be concluded that the
most damaging floods along Rifle Creek and Gov-
ernment Creek have been the result of high in-
tensity, short duration rainfall. Ai; stated above,
such cloudbursts generally occur during the
summer months, but as the May 15th flood dem-
0nstrates, they can occur earlier in the year as
well.

The 1930 Flood

The worst flood in Rifle history, prior to the May
15th 1993 flood, happened on August 8th 1930,
in the midst of what was then the worst drought
in U.S. history. The flood was caused by a 2-hour
cloudburst that produced high peak flows in both
Government and Rifle Creeks. The flood washed
out two bridges, undermined railroad tracks,
flooded the train station and inundated the sew-
age treatment plant as well as the bulk storage
facilities of six oil companies. The flood also
claimed the life of a state highway patrolman.
Unlike the May 15th 1993 flood, the 1930 flood
caused only minor flooding in some homes.

The most recent floods of importance occurred in
August 1963. On August 9th, flood flows from a
cloudburst severely damaged the Pioneer Ditch
diversion in Rifle. In areas nearby, roads were
covered with mud, agricultural facilities were
damaged and a large culvert was destroyed. On

August 12th, another cloudburst resulted in the
flooding of several downtown streets causing se-
vere damage to streets and deposition of tons of
sediment and other flood debris on streets and
roads. It is clear that the City of Rifle is vulner-
able to flash flooding from intense local cloud-
bursts.

Damaging Floods Within the Rifle
Creek Basin occurred during 1914,
1917, 1921, 1929, 1930, 1937, 1945,
1947, 1951, and 1963.

Dam Failure Flood Hazard

The Rifle Gap Dam, an irrigation water dam
owned by the U.S. Bureau of Reclamation, is
located at the confluence of East Rifle Creek and
West Rifle Creek, about 7 miles upstream of the
City of Rifle. The dam and associated reservoir
provide no flood control protection for the City of
Rifle. The reservoir holds about 11,000 acre feet
of water. The dam is a Class I high hazard dam,
indicating potential loss of life and damage to
property should the dam fail. It is estimated that
in the case of a dam failure the flood wave would
reach the City of Rifle in under one half hour. The
City would be subjected to wide-spread flooding.

Vehicle W_hed DowrutreamAlong RilL< Creek

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