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Iv. Investigation of River Restoration Activities
<br />The key focus questions to be answered are:
<br />1 Is the clearing and lowering of vegetated river islands an effective way to widen the channel and provide a new source
<br />sand to the river?
<br />2 How many acres of river islands would have to be cleared and lowered to supply enough sand to offset channel
<br />degradation?
<br />3 By extrapolation from field tests, how many acres of islands could be cleared and lowered in one year without having
<br />impacts to people or property?
<br />4 Can pulse flows be used to prevent vegetation from colonizing areas of the channel that have been mechanically wide
<br />5 Can pulse flows be used to create sandbars that provide suitable nesting habitat for terns and plovers?
<br />6 Do the newly created sandbars eventually become colonized by vegetation?
<br />7 What is the relationship between sandbar height, flow history, and vegetation growth?
<br />Question Answered By:
<br />61- 5,7 -8, C5 -7, D1, E3, 171 -2
<br />.A1 -3, B1- 5,7 -8, C5 -7, D1, E3 -4, F1 -2
<br />B1- 5,7 -8, C1 -7, D1, E14, F1 -2
<br />A1-6, 61- 5,7 -8, C1 -7, D1, E2 -3, Ft -2
<br />A1-6, B1- 5,7 -8, C1 -7, D1, E14, F1 -2
<br />86-8, C6-7, D1, E24, F1 -2
<br />82,6 -8, C5 -7, D1, E14, F1 -2
<br />scope or vvorK
<br />This study will test the performance and effects of pulse flows, measures to remove vegetated islands, and measures to create sand bars. The pulse flow
<br />would be tested in three phases: The first, initial phase would be to gather information on discharge wave travel times and wave attenuation and on river
<br />stage at locations where there is concern about potential flooding problems. Data from this first phase would be used to design the pulse flow magnitude
<br />the second phase to be within the safe channel capacity. Four study reaches would be selected between the J -2 return channel and Chapman, NE.
<br />Selected vegetated river islands would be cleared and lowered from each of the four study reaches prior to the second pulse flow test. The second and
<br />third pulse flow tests would be conducted to study the removal of new vegetation on the river bed and sandbars, the building of new sandbars (with and
<br />without woody debris), and other sediment transport processes. The performance and effects of other restoration treatments would also be tested. There
<br />is a linkage between restoration treatments that would widen the channel and the pulse flow which is designed to prevent new vegetation growth from colt
<br />Budget Summary
<br />Totals
<br />Year 1
<br />Year 2
<br />Year 3
<br />Year 4
<br />Yrs 5 -13
<br />Labor Cost
<br />$760,900
<br />$266,900
<br />$266,000
<br />$66,000
<br />$39,000
<br />$123,000
<br />Direct Non -Labor Cost
<br />$112,600
<br />$45,000
<br />$43,100
<br />$3,500
<br />$3,000
<br />$18,000
<br />Contract Services
<br />$125,000
<br />$0
<br />$45,000
<br />$0
<br />$0
<br />$80,000
<br />Contingency
<br />199 700
<br />$62,380
<br />$70,820
<br />$13,900
<br />$8,400
<br />$44,200
<br />TOTAL
<br />1 198 200
<br />$374,280
<br />$424,920
<br />$83,400
<br />$50,400
<br />$265,200
<br />20%
<br />
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