FLOOD03460

• Designation Number: 481
• County: Larimer
• Community: Unincorporated Larimer County
• Basin: South Platte
• Title: Flood Insurance Study - Larimer County, CO, Unincorporated Areas
• Date: 7/1/1997
• Designation Date: 1/1/1999
• Floodplain - Doc Type: Floodplain Report/Masterplan

The U.S. Army Corps of Engineers (COE), Omaha District, was
contacted and provided flood plain data 'on the Big Thompson and the
Cache La Poudre Rivers for use in preparing the Flood Insurance
Study.

During the work by the study contractor, flood elevations, flood
boundaries, and floodway delineations were reviewed with community
officials.

Final coordination meetings were held in Loveland and Fort Collins
on November 29 and 30, 1977, respectively. These meetings were
attended by representatives of Larimer County, FEMA, the study
contractor, and the general public. The results of these meetings
have been incorporated into this report.

Streams requiring additional detailed study were identified at a
meeting attended by representatives of the study contractor, FEMA,
Larimer County, and the Town of Estes Park in April 1983. The
results of this additional work were reviewed at a meeting attended
by representatives of these groups on February 27, 1986.

2.0 AREA STUDIED

2.1 Scope of Study

This Flood Insurance Study
Larimer County, Colorado.
Vicinity Map (Figure 1).

covers the unincorporated areas of
The area of study is shown on the

The following streams were studied in detail: Big Thompson River;
Big Thompson Tributaries 1, 2, 3, and 4; Buckhorn Creek; Cedar
Creek; Dark Gulch; Dickson Gulch; Dry Gulch; Glade Road Overflow;
Long Gulch; Noel's Draw; North Fork Big Thompson River; Quillan
Gulch; Rabbit Gulch; Redstone Creek; Bobcat Gulch; Miller Fork; Fox
Creek; West Creek; Devils Gulch; Cache La Poudre River; Dry Creek;
Boxelder Creek; Fall River; Fish Creek; and Black Canyon Creek.

The areas studied by detailed methods were selected with priority
given to all known flood hazard areas and areas of projected
development or proposed construction through 1990.

Approximate analyses were used tO,study those areas having a low
development potential or minimal flood hazards. The scope and
methods of study were proposed to, and agreed upon by, FEMA and
Larimer County.

.
The upper and lower reaches of the Cache La Poudre River northwest
and southeast of Fort Collins, the Little Thompson River, Cooper
Slough, Boxelder Creek from its confluence with the Cache La Poudre

2