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Summary Update for Greenough Bridge Replacement & Stream Bank Restoration April 21, 2010 The history of this project began during the high water run-off in the spring of 2008 in Rattlesnake Creek. The rapid melt and high run-off that spring forced the removal of both east channel bridges to protect them from flood damage. The lower bridge was able to be reset the following summer but undermining and scour of the upper bridge’s abutments has prevented it’s resetting. At the same high-flow time, a serious bank scouring occurred in the main channel about 150’ upstream of its footbridge forcing closure of the walking trail and eventually, its realignment away from the stream channel. From this point forward the situation becomes increasingly more complicated and challenging. Rattlesnake Creek has many friends and regulatory agencies watching over and providing stewardship for its future. Many of these became partners in varying degrees in the effort to re- establish a footbridge to the braided area between the main stem and east channel. Parks and Recreation joined with PBS&J (a local environmental engineering firm) in 2008 to help plan the segments of the project and properly steer the City through the agencies, permits and approvals necessary to undertake any construction work in, around or over this pristine watershed which happens to be prime Bull Trout spawning and rearing habitat. Bull Trout are a federally protected species making the project approval considerably more complex and difficult. HDR Engineering designed the resetting of the existing bridge on new abutments and provided the necessary plans. PBS&J designed the restoration of the bank channel in the main stem and a woody debris catch and high flow diversion in the upper reaches of the east channel to protect it from run-off scouring of habitat and structure. PBS&J assembled and orchestrated the filing of the permit applications and navigated the project through the difficult process which lay ahead. Streamside meetings were held with all the regulatory agencies including; The US Army Corps of Engineers; US Department of Environmental Quality; US Fish and Wildlife; Montana Fish Wildlife and Parks; Flood Plane Administration as well as Parks own mandate to “maintain the park naturally”. All agencies, save one, agreed to let P&R proceed with re-installing the existing bridge on new abutments to save money and restore access. That one agency carries a lot of weight though and insisted upon a longer span to permit “full bank flow” of the side channel. The current status is that we now have concurrence from all agencies except one to proceed with a new timber bridge in the forest service trail bridge standard design which is very heavy duty. Montana Fish Wildlife and Parks has been very supportive and is donating the hard-to-find ---PAGE BREAK--- stringers for the main support of this structure. PBS&J has also gone “over the top” by donating their services throughout this whole project. We are extremely grateful. The University of Montana, College of Technology Heavy Equipment Program has also been our very supportive ally and will be performing the bulk of the construction work to restore the stream bank and construct the abutments preparing the way for the bridge to be built. We could not even entertain this project without the support rallied by our partners. Once full approval is obtained, hopefully by the end of May, we will be allowed to work between July 1st and October 31st, 2010. The majority of the funding has been provided by a HB 645 Stimulus Grant awarded to the city by the State of Montana.