FLOOD03000

• County: Statewide
• Stream Name: South Platte
• Basin: South Platte
• Title: Water and Related Land Resources Management Study Volume V - Appendix H
• Date: 7/14/1980
• Prepared For: South Platte and Tributaries
• Prepared By: CWCB
• Floodplain - Doc Type: Flood Mitigation/Flood Warning/Watershed Restoration

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The downstream channel and drainage improvements, which are

also a local responsibility, would provide additional flood

protection for that area. Optimization studies indicated that

net benefits would maximize for a channel with a capacity

slightly greater than the 5-year flood. A channel with capacity

for the lO-year flood was selected, however, because net benefits

would be only slightly lower.

Optimiza tion studies of storage at Kelly Road and Upper Lowry

Dams indicated maximum net benefits for a plan which would

provide storage for a 50-year flood at Kelly Road Dam and no

storage at the Upper Lowry site. However, a plan with storage

for the standard project flood at Upper Lowry would, with

improvements at Kelly Road Dam, provide Kelly Road Dam with a

capability of storing the standard project flood. The plan with

storage for the standard project flood was selected because net

benefits approach the maximum and the plan would provide a

significantly higher degree of protection.

The selected plan also includes flood plain management and an

evacuation plan for the area downstream from Kelly Road Dam.

The total estimated first cost of the selected plan is

$2l,794,000. Under existing legislation concerning cost-sharing,

the construction cost of $7,795,000 for improvements to Kelly

Road Dam and construction of Upper Lowry Dam would be a Federal

cost. The value for the required lands which are already

federally owned is $3,485,000. The above construction costs

include $l,060,000 for the emergency measures on Kelly Road Dam.

Non-Federal costs would include $3,320,000 for detention storage

and drainage improvements in the upstream part of the basin,

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