Station 3
Water Modeling & Economic Analyses

Water modeling is being completed in order to evaluate baseline conditions with and without dams. The water modeling data was then incorporated in to economic models to evaluate the retrospective benefit cost ratio of the dams. In other words, before evaluating whether or not the dams should stay or go, it was wise to look at what benefits they have provided over the last 60 years.

Flood System Retrospective Benefit Cost Analyses Results

Preliminary Indicators:

  • The economic benefits are flood costs avoided by having dams in place since the 1960’s

  • Benefits of protecting land uses in the valleys was small, because dams reduce the floodplain by less than 300 acres in each watershed. 

  • Benefits of avoiding streamside infrastructure damage and emergency service delays were higher than originally planned.

  • Avoided streamside infra-structure damages and lower emergency services are higher

  • Recreation, particularly blue-ribbon trout fishery & Jersey Valley, are now dominant benefits

  • Structure and crossings avoided damages are being calculated

A benefit cost ratio (BCR) at 1.0 or above describes the benefits out weighing the costs. While these analyses are preliminary, it describes both watersheds heavily reliant on recreational benefits. We strongly encourage participation in, or listening to the recording, of the live scoping meetings for the economist's interpretation and analysis of this complex data.

BCA - Copy.PNG
BCA.PNG

Utilizing those benefits, combined with the number of acres protected by the dams, the following baseline conditions with and without the dams apply:

Coon Creek

19% of the watershed is controlled with the 14 structures

With all 14 Dams

  • 100-year floodplain​ is2,705 acres

Without any of the 14 Dams​

  • 100-year floodplain is 2,933 acres (228 acre increase) 

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Without 3 Failed Dams, 11 Existing Remain

  • 100-year floodplain is 2,796 acres (91 acre increase) 

West Fork Kickapoo

35% of the watershed is controlled with the 9 structures

With all 9 Dams

  • 100-year floodplain​ is 2,149 acres

Without any of the 9 Dams​

  • 100-year floodplain is 2,419 acres (270 acre increase)

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Without 2 Failed Dams, 7 Existing Remain

  • 100-year floodplain is 2,241acres (92 acre increase) 

Summary

This analysis is looking at the previous 60 years, on the next page, we will review alternatives to address the five failed dams for the future. The decision made on the 5 failed dams will provide a road map for the Counties on how to address the remaining 18 dams that continue to age within the watersheds. Public input is a vital component to the decision making process and your opinion is valuable and appreciated.