A flood control reservoir project improvement proj ect are proposed for  reducing flood da...

A flood control reservoir project improvement proj ect are proposed for  reducing flood damages along a stream in an urban area. Estimated costs are as follows:

Hydrologic, hydraulic, and economic studies have been conducted to develop the following relationships for the river reach and floodplain: (a) annual exceedance probability versus peak discharge with and without the reservoir, (b) discharge versus stage with and without the channel improvement, and (c) stage versus damage.

Perform an economic evaluation of the following alternative plans using a 50-year period of analysis and 8 percent discount rate. Determine the net benefits and benefit-to-cost ratio for each plain. Select the economically optimum plan.

Plan 1—no action

Plan 2—construct the reservoir project

Plan 3—construct the channel improvement project

Plan 4—construct both the reservoir and channel improvement projects.