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i oxbow lakes, former side channels in broad valley floodplains, ponds, apd wetland depressions. During high flow events, some of these off-channel features were temporarily connected to the river in the past. These former naturaJ riverine features could be integrated back into the historic floodplain b~ removing portions of man-made dikes or natural obstructions (e. g., gravel/saDd bars). Background Although gravel pits are artificial environments that are typiqally diked and isolated from the mainstem river, they comprise a large proportibn of pond habitats created by gravel-pit mining in the floodplain in some rive~ corridors along the Upper Colorado River. Much of the floodplain habitat in) the Upper Co 1 orado Ri ver from the Colorado-Utah state 1 i ne upstream to Ri fl e, cq 1 orado, on the Colorado River and upstream to Austin on the Gunnison River has be~n modified by humans either from levee construction or mining gravel. There are I four areas along the Upper Colorado River where gravel-mining operations ha~e created numerous pits that vary in size, depth, shape, and orientation to the mainstem river: the Grand Valley between Palisade and Lorna, Colorado (15- ~nd 18-mile - reaches), between Rifle and Debeque, Colorado, and near Delta, Color~do, on the Gunnison River. For example, Mitchell (1995) identified 243 ponds within 1 mile either side of the Upper Colorado River between Palisade and Lorna. He!calculated that these ponds totaled approximately 713 surface acres of standing ~ater. Most of these ponds were created either from gravel mining or for sewage treatment pl ants. More importantly, these ponds are located in the former floodpl ain. Historical aerial photos of this same area reveal very little gr~vel mining activity and ponds as late as 1954. In 1937 and 1954, there were no gravel pits in this reach and only 'virgin' floodplain existed where the 29-5/8 Road gravel- pit pond site occurs today. Even more dramatic is the approximate ~5 miles of man-made dikes in this 33.mile stream reach between Pal isade and Lorna !(Irving and Burdick 1995) that effectively prevent inundation of potential !off-channel habitats and fish access to historic floodplain habitat. I During high flow events, some of these ponds have temporarily 40nnected to the ri ver all owi ng access to fi sh . However, these ponds that ~o not hav permanent connections to the river have also trapped fish following tecessiun' high flows. Ponds that are reconnected to the river are less 1 i~elyto tra endangered fishes. Integrating ponds created from gravel-pit minilng into th historic floodplain by removing portions of dikes, resloping gravel!pits towar the river, and re.establishing connectivity to the river may provideloff-channe habitats which are beneficial for effective management of the riveripe ecosyste and recovery of endangered fishes. i Most researchers believe that connecting isolated ponds to the river ca be seasonally beneficial to endangered fishes. Ponds that are gentl~ graded an connected to the river should be evaluated for their use and Ibenefit f r endangered fishes by providing off-channel habitats while reducing qr minimizi g proliferation of nonnative fishes that may compete with or Rredate up n endangered fishes. Valdez and Wick (1983) and Osmundson and Ka~ding (199 ) hypothesized that graded gravel pits that flood during runoff an~ drain wi h descending flow may benefit adult razorback sucker and Colorado ~quawfish y providing feeding, resting, conditioning, and possibly spawning ar~as. Habit t 2