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jurisdictional authority to regulate excavation of fill material in wetland areas and below ordinary high water in riverine reaches where critical habitat has been designated for endangered fishes. In the future where possible, as a condition of being granted a 404 permit, gravel-mining companies that create ponds in wetlands adjacent to the river could be required to create stepped terraces leading to the river during their mining activities so that the terraces drain when high streamflows reside. Eventually, the ponds would then be reconnected to the river when mining activities are completed as part of their reclamation procedures. Whenever floodplain habitats are connected to the river, hydrological access for fish should be by surface connection. Underground culverts and pipes should be avoided because some native fish might be shy and will not use such structures. 2. Notch Dikes and Levees Protecting Gravel Pits. Reconnect former floodplM habitats without deep depression ponds with the river to enhance or restore the natural function of the river ecosystem. Such former floodplain habitats have been separated from the river by levee construction so it would be cost-effective and practical to acquire rights to use land through easements or fee-title so the floodplain could be reconnected with the river by excavating a notch. Although it might be desirable to implement recommended river flows that would inundate floodplains in the spring during May and June to provide off- channel habitat for endangered fish, adequate flows might not be available frequently enough to benefit recovery of the endangered fishes. Therefore, notching old levees and dikes at strategic locations could provide some level of protection from flooding to agricultural land, and residential and recreational structures (i. e., set-back dikes) and also provide access to floodplain habitats to various life stages of endangered fishes. Dikes and levees constructed to protect gravel-mining operations could be removed following gravel mining to permit reconnection of the floodplain and the river. The floodplain could then function as it did historically, recreating new in-channel habitats. Some of the features created would be flow-through side channels that might create a complex of habitat types. An ancillary benefit for modifying gravel-pits protected by levees and dikes to allow these habitats to communicate with the river during runoff is flood control. In addition to isolating off-channel, productive areas from aquatic organisms, levees and dikes have reduced the channel width and thus the river's ability to convey large volumes of water during runoff. In some areas protected by levees and dikes, runoff water now inundates adjacent low-lying areas at lower discharges than did historically. Flood-control management strategies would be to notch levees and dikes to allow inundation of low-lying areas and also reclaim gravel-pit ponds as sloped terraces or side channels. Restoring gravel pits to function as historical terraces or side channels may not only benefit native fishes but may actually provide county, state, and federal agencies more flexibility in 25