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installation of weirs or jetties along the outside edge of an eroding river bend (see Alternative Bank Stabilization article in this issue). So far the project has been successful at arresting bank erosion and protecting against loss of riparian vegetation and wildlife habitat. Cooperative Projects With Private Property Ownen In 1997 two more cooperative projects were completed. The first coop project involved bank restoration along 1,100 feet of property owned by Mr. and Mrs. Jack Rogers near 168th Avenue in Adams County. The project arrested bank erosion that threatened to breech the existing berm separating the river and the adjacent sand and gravel miuing operation. The second coop project completed in 1997 involved bank stabilization of 850 feet ofbadly eroded bank one-half mile downstream of Brantner Ditch diversion structure and adjacent to the Suburban Sand and Gravel pit operated by Aggregate, Inc. Part of the owner's contribution to this project included labor, equipment, and materials at a below-market price, in addition to the dedication of a flowage and maintenance access easement. The bank was seeded and mulched with native grasses. Live stake willow planting along the bank will take place in early spring of 1998. Two new cooperative projects have also been started. One will clean up a river bank covered with broken concrete pipe, bed springs, car bodies - you name itl Albert Frei and Sons, the McIntosh Farm Company, and the District have agreed to jointly fund, by way of easement dedication and below- market equipment and material costs over 1,400 feet ofbank cleanup, ' stabilization with buried riprap and rubble, and revegetation with native grasses and willow. As a follow up to the success with Aggregate, Inc. on the above-mentioned project, the District entered into another cooperative agreement with them. This one will restore 1,100 feet oferoded bank approximately one mile further downstream. We expect both of these new projects to be completed by the spring of 1998. - An example of a matoring restorative maintenance project is the project completed three years ago along the east bank of the river just upstream of 160'" Street Bridge (Figure I). At this location the bank and overbank were covered with concrete rubble and asphalt slabs. Although a few small Siberian Elm trees and other exotic vegetation established themselves in the rubble, the bank was very steep and offered virtually no wildlife habitat. Now the bank is much flatter and is covered by a healthy stand of new trees shrubs and native grasses. ' Capital Improvement Projects Upper Central Platte Valley Projed During the last three years we have been working with Denver and the Public Service Company of Colorado (PSCo) to develop and design the Upper Central Platte Valley Project. PSCo, the owners of the Zuni Electric and Steam Generating Plant, has agreed to a concept of switching its cooling system from one-pass conductive cooling to a closed-loop, recirculating evaporative system. When this is done, ouly 10% of the water currently being diverted will need to be diverted in the future. This reduction will permit the use of an infiltration gallery for water diversions instead of a diversion dam and other associated surface structures. After a year of testing a prototype system constructed within the river channel itself, we have concluded that an infiltration gallery will reliably provide the needed water. Water quality samples show that water from the gallery compares well with the surface water quality, and should provide little operational difference to PSCO in the future. Once the switch from surface diversion to an infiltration gallery is made, the options for river rehabilitation expand and allow for a more aesthetic "natural" appearance and much improved boating and aquatic and terrestrial habitat. This progress notwithstanding, funding the construction of this river restoration project remains a major challenge. Globeville Area Project The other ongoing capital project along the river is located in the 7 ""T""--~ Figure 1. Completed rcslorath'c mainten- ance pmject at 160lh A\'C. Globeville neighborhood in north Denver. Phase I of the project covering 2,000 feet of South Platte River has now been completed (Figure 2). Despite the fact that this is a flood control project, the primary focus was on river bank and aquatic habitat rehabilitation. Improvements also included the construction of a recreational trail and better access to the river by the adjacent commuuity. ConstnJction of Phase II , encompassing another 5,000 feet of the river upstream of Phase I, is under way. We expect this construction to be completed by May of 1998. The funding for the final phase (phase III) of this project, which is inunediately downstream of Phase I has now been identified. Denver au'd the District expect to commit approximately $6,000,000 for this key link of this flood protection and recreational improvements project. A physical hydraulic model of Phase III is now under constnJction at the Colorado State Uuiversity hydraulics laboratories with the test scheduled to begin in ' March of 1998. We hope to have this phase of the project under construction in 1999. Once completed, approximately 300 acres of existing inner city residential industrial and commercial area will ~ removed from the lOO-year regulatory floodplain. In addition, 7,000 feet of the river's channel will have been rehabilitated, a recreational trail separated from traffic and connected to the Adams County's trail system, and the community's access to the river and the environment for this old neighborhood of Denver will be siguificantly improved.