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Ouray National Wildlife Refuge Sites <br />Johnson - 4 Bottomland -Johnson-4 has a proposed 100' wide cut located where the Johnson-4 <br />bottomland drains (See Exhibit A). A major design consideration is that once the J-4 bottomland floods, flows <br />over 13,000 cfs will overtop the levee at the upstream end of J-4 and flood the more extensive upper Johnson <br />bottomlands. One objective of the bottomland floodplain habitat restoration study is to be able to monitor the <br />flooded area. Therefore, the spoils materia! will be used to build up the levee between J-4 and J-3 and <br />prevent the flooding of the J-3 bottomland for discharges up to 30,000 cfs. To accomplish this, 40 cubic yards <br />of additional fill material would be required in addition to the spoils material. The flooding elevation of 4667 <br />would be set back 100' from the bank. The amount of cut vegetation will not be as great for the Johnson <br />Bottom as it was for the BLM bottomlands. The success of the bottomland floodplain habitat restoration <br />activities will be assessed before modifications to J-4 are employed. Construction activities are not planned <br />any earlier than the fall of 1997. The estimated costs of restoration activities varies from $15,000.00 to <br />$150,000.00 depending on the usage of a drainage structure and/or fish kettle. (Note: The fish kettle costs <br />range from $80,000.00 to $100,000.00) <br />Leota - 7 Bottomland -The Leota-7A pond provides another opportunity to flood shallower pond <br />(compared with the BLM sites) which will act somewhat like a terrace, as defined by the recovery program. <br />The Green River flows right along aman-made levee which separates it from Leota Pond-7A. The Leota-7A <br />pond is not managed as a waterfowl habitat pond by the ONWR personnel. The proposed design is to breach <br />600' of the levee (see Exhibit A). Similar to the Johnson-4 design, adjacent Leota ponds would be inundated <br />if the floodability were enhanced at Leota-7A. Consequently, the adjacent levee would need to be raised. The <br />spoil material will be used to build up the levee along Leota-7 and Leota-9, the adjacent ponds. An additional <br />6480 cubic yards of. fill material will also be necessary to prevent flooding up to 30,000 cfs. Some borrow <br />material may be available in ditches located along the Leota Ponds. The flooding elevation will be set back <br />approximately 50'-70' from the river. The estimated construction costs at Leota vary from $47,000.00 to <br />$186,000.00 depending on the use of a drainage structure and/or fish kettle. <br />Wyasket Bottomland - An enormous bottomland providing up to 2000 acres of floodable area, <br />Wyasket Bottomland provides an opportunity for large scale habitat enhancement. The proposed design is <br />to widen and lower an existing channel which connects the river to Wyasket Bottom (see Exhibit B). The size <br />of the bottomland would, however, make monitoring of the bottomland difficult. The success of the bottomland <br />floodplain habitat restoration activities will be assessed before modifications to Wyasket are enacted. <br />Construction activities are not planned any earlier than the fall of 1997, and are subject to the success of the <br />other restoration activities. Approximately 2500' of the existing channel would need to be modified. Survey <br />data on the proposed location is limited and additional data would need to be gathered prior to any final <br />designs being submitted. <br />Sheppard Bottomland -The Sheppard Bottomlands are another series of bottomlands used mostly <br />for waterfowl habitat on the ONWR. It has been proposed that 100' of the Levee along the river adjacent to <br />S-2 of the Sheppard Bottomland be removed (see Exhibit B). The cut would have to extend back <br />approximately 300' back to the bottomland. Similar to Johnson-4 and Leota-7, the ponds adjacent to S-2 may <br />flood if the adjacent levees are not raised. Alternative 1 includes the levee buildup while Alternative 2 <br />proposes to place the spoils above the high water mark and allow the adjacent ponds to flood at higher <br />discharges above approximately 14,000 cfs. The Sheppard bottoms also have problems with selenium <br />concentrations in the water, which may influence any enhancement activities from being implemented. No <br />work is proposed for Sheppard-2 until the fall of 1997 at the earliest, and modifications are subject to the <br />success of the other restoration activities. <br />• <br />57 <br />