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2. protect the bank. In other locations, n ' umerous trees and shrubs remain but are being undermined and either sliding, roots and all, down the slope to the river or toppling into the river. The.distance between the edge of the North Shore Drive pavement various with location. The FWS believes that no one alternative.could be successfully utilized for the entire project area because of the variability of the situation on -the -ground. Soil stability and degree of erosion should be determined along the entire length of the slope, since the erosive pressure of the flowing river is not uniform across the entire area. Once this is determined, the areas with the greatest potential for erosion can be located and individual methods of adequately addressing the problems can be developed. For example, during the very low water conditions during our site visit, we noted that a "delta" has formed in the river, extending from the south bank past mid - river, in the vicinity of the CSO #6 near Riverside Drive and Leland Avenue (Photograph No. 1) . This higher elevation in the river bottom is pushing flows, at least lower flows, toward the north bank. Removal of this delta in an environmentally acceptable manner, and control of the sources of the sediments that are creating it, could greatly relieve erosive pressures against the north,bank. If the CSO's contributions of sediments into the St. Joseph River are not addressed, a 1 -time removal of the delta would have little lasting affect. Modeling of the river dynamics in the project reach and upstream from it could likely provide significant information toward developing an engineering soluEi7on that will be successful in the long term. Otherwise, a COE project at the site might not be any more successful than the -local projects have been in correcting the situation. The FWS strongly recommends that a projectbe developed that fits the river dynamics of the reach and also saves as.many of the riverbank trees as possible. These trees have lessened the erosion by holding the soil. They also provide fishery habitat in the form of detritus and shade. Root wads in the water provide shelter for fish and other aquatic organisms. The root wads at the base of the slope also help hold the bank against erosion. Additionally, the trees and shrubs along the riverbank are very important for.the human environment because of their aesthetic value and value in reducing air pollution and summer heat in this urban setting.. Neither of the alternatives as presented are acceptable to us because either would i , mpose just one solution for the entire reach of the river. One or the other of the 2 alternatives might be acceptable for a specific site but either could actually inc I rease the problems at other sites. Also, less "engineered" and more "bioengineered" alternatives should be considered, based upon the results of the river dynamics modeling. Since this is a very aesthetically attractive urban residential setting, steel sheet pile and heavy riprap would not enhance the quality of human life in the area any more than it would enhance the biological quality of the reach. Riverbank trees should be saved and those unavoidably lost would need to be -replaced. Numerous species of fish are found in this portion of the St.- Joseph River. During a 1979 fishery survey of the river, Indiana Department of Natural Resources' biologists sampled the reach immediately upstream from the project site, in the vicinity of Leeper Park (Ledet, N.D. 1979. A fisheries survey of the St. Joseph River in St. Joseph and Elkhart Counties, Indiana. Indiana Department of Natural Resources, Division of Fish and Wildlife. 4!pp,) . Sportf ish included smallmouth �4