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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1. The hydraulics of the existing channel would be improved
along present course of the existing natural channel,
increasing the carrying capacity of the river and
reducing the probability that the river would have to
seek new channels during a flood. It was assumed that
the channelization would follow the existing natural
course of the river, staying within and along existing
legal property boundaries and would not be "forced" into
an engineered channel.

2. The natural channel would be improved by removal of sand
and gravel bars and widening the existing channel within
the existing clear floodway. For this estimate, the
width of the channel was determined from the existing
depth, slope, roughness coefficient and flow of the 100
year flood for that reach of the river. The amount of
material to be moved was estimated from aerial
photographs and site visits.

3. It was assumed that the sand and gravel bars would not
have to be moved a great distance to reshape the channel
to a desirable contour (in this case it was assumed that
only a 50-100 foot "dozer push" would be required). the
local-contractor cost for this type of earth moving is
approximately $3 per cubic yard.

This assumption is an important cost consideration
because if assumes that there will not be high costs
incurred to completely rechannel the river to what the
adjacent land owners believe to be the historical
channel. The river will remain where it is now and
would be stabilized. In most cases this follows the
historical property boundaries but in some areas the
river has relocated to such an extent that large
cultivated fields have been divided and in one case the
arable land of an entire farm was washed out. The
estimate does not include any contingencies for these
particular cases.

4. the cost for channelization of the river, removal of sand
bars and bank protection is separate from the cost of
debris removal which would have been completed.

5. This type of project is extensive and even the most
rudimentary removal of sand and gravel bars for the full
extent of each of the rivers would be very expensive.
the cost of this portion of the project is based on 1985
dollars but the project should take two to three years to
complete, inflating the cost.

6. Removing the existing sand and gravel bars will not
permanently solve the existing problems. They exist now
because of the recent floods and the lack of maintenance
over the last few years historically provided by the

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