FLOOD05149

• County: Delta
• Community: Delta
• Stream Name: Gunnison, Uncompahgre Rivers
• Basin: Gunnison
• Title: Cost Estimates for Removal of Debris, Bank Protection and River Training Along the Uncompahgre, Gunnison and the North Fork of the Gunnison Rivers
• Date: 1/1/1980
• Prepared For: Delta County
• Prepared By: Mt Highland Engineering
• Floodplain - Doc Type: Miscellaneous

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SOURCES OF INFORMATION

The cost estimate for removal of sand and gravel bars, and
channelization along the rivers was based on:

1. Interviews with selected land owners along each of the
rivers and field investigation of other sites along each
of the river reaches under investigation.

2. Aerial photographs taken by ASCS in spring 1984

3. Aerial photographs taken by Delta County in spring 1984.

4. USGS Quadrangle Sheets

5. Flood Insurance Study of Delta County
Unincorporated Areas, September 15, 1983.

Colorado,

The measurements for length and cleanup areas were scaled from the
high resolution aerial photographs taken for Delta County in early
spring of 1984. The Delta County Photographs were flown at the
peak of the 1984 spring flood and graphically depict the flood
prone areas along each of the river. The good resolution of the
photographs made it easy to map the problem areas of the river
with reasonable accuracy.

Although the Delta County photographs could be used to outline
problem areas in the rivers, other sources of information were
used to supplement or verify this data. The best source of
information about the river and its history was from interviews
with the owners of the land along the rivers. They were extremely
helpful in determining the historical channels, and what extent
the private landowners have tried to maintain those channels.

Another good source of verifying information came from the
Agricultural Stabilization and Conservation Service (ASCS)
photographs which are flown every year in the spring. The 1984
photographs were flown after the flood waters had subsided. the
photographs were taken with 35 rom color film and were not to a
constant scale although landmarks were used to calculate a scale
on each photograph. Also, because the photographs were color, the
development was easier to discriminate from the natural riparian
vegetation.

METHODS OF CALCULATION

Assumptions

Several assumptions
rechanneling certain
banks.

were made
stretches

to
of

determine
the river

the costs of
to stay within its

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