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<br />2. Back-Fill Gravel-Pit Ponds and Reconnect them to the Mainstem River to <br />Flood and Drain Seasonally to Benefit Native Fishes and to Control <br />Nonnative Fishes. As a part of restoration, where feasible and <br />practical, gravel-pit ponds that are relatively shallow could be back- <br />filled, sloped to drain as the river subsides, and allowed to function <br />as an ephemeral wetland. Reconnecting former floodplain habitat to <br />the river to provide off-channel habitats will benefit native fishes. <br />This action would include eradicating nonnative fishes from depression <br />habitats such as former gravel-pit ponds prior to their being back- <br />filled and the pond bottom recontoured so that they slope toward the <br />river to allow seasonal flooding and draining, even during high-water <br />years. The bottom of shallow gravel-pits could be back-filled and <br />recontoured to create stepped terraces leading to the river so that <br />they slope toward the river. These features would then~cotmec-t-ed <br />to the river to allow fish access during high-flow periods. Modifying <br />these man-made gravel-pit ponds to function as historical terraces may <br />be more cost-effective and practical for managing and controlling <br />nonnative fishes than long-term control measures such as screening <br />ponds, chemical treatment, or mechanical pumping and removal. <br /> <br />3. _Coordinate Recovery Proqram Efforts with Companies to Restore Gravel- <br />Mininq Areas to Function as Historical Terraces to Benefit Native <br />Fishes. Rip-rap in levees and dikes, constructed to protect gravel- <br />mining activities and to prevent flooding in low-lying areas along <br />some stream reaches in the Grand Valley along the Upper Colorado <br />River, has reduced the width of the river channel. Implementing new <br />procedures to reclaim ponds as sloped terraces that flood and drain <br />seasonally to benefit endangered and native fishes would have to be <br />coordinated with and mut~ally agreed upon by gravel-mining companies, <br />Colorado Mined Land Reclamation, and Recovery Program participants. <br />Reclamation procedures should include the specifications for designing <br />and contouring the bottom in these ponds to slope toward the river to <br />allow seasonal flooding and draining. These conditions should be <br />identified when mining permits are initially issued. The U. S. Army <br />Corps of Engineers now has the jurisdictional authority to regulate <br />excavation of fill material in wetland areas and below ordinary high <br />water in riverine reaches where critical habitat has been designated <br />for endangered fishes. <br /> <br />In the future where possible, as a condition of being granted a 404 <br />permit, gravel mining companies that create ponds in wetlands adjacent <br />to the river could be required to create stepped terraces leading to <br />the river during their mining activities so that the terraces drain <br />when high streamflows reside. Eventually, the ponds would then be <br />reconnected to the river when mining activities are completed as part <br />of their reclamation procedures. Whenever floodplain habitats are <br />connected to the river, hydrological access for fish should be by <br />surface connection and underground culverts and pipes should be <br />avoided because some fish might be shy and will not use such <br />structures. <br /> <br />12 <br />