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Longitudinal Stream Profile Stability and Countermeasure Recommendations <br />Longitudinal stream channel profile stability issues may need to be addressed at several of the crossings to <br />prevent undesirable impacts to adjacent private property. If an existing crossing currently provides grade <br />control, the stream's longitudinal profile may adjust when a replacement crossing is installed. This could <br />lead to channel incision upstream and sediment deposition downstream. if profile instability issues are <br />likely, WSE will recommend countermeasures. <br />Local Scour and Erosion Assessment and Countermeasure Recommendations <br />WSE will assess each proposed crossings for scour and lateral erosion potential and will recommend <br />countermeasures if they are needed. <br />Steam Bed Material Recommendations <br />WSE will recommend stream bed material gradations to be used for each site. Gradations will be based <br />upon a review of natural bed material characteristics and gradation estimates computed using published <br />WDFW formulas. <br />Hydraulic Design Report <br />A technical report will be prepared for each crossing to document methods and results. The four individual <br />reports will be combined under a single cover and provided to the County for review and comment. Upon <br />receipt of the comments, WSE will prepare and submit the final report. <br />Environmental Permit Support <br />WSE will provide materials needed to support preparation of the permit applications <br />Meetings <br />An allowance is provided for WSE staff to participate in the following project meetings: <br />One field meeting with resource agency personnel to discuss proposed designs <br />Up to two meetings with County project staff — specific purpose to be defined. <br />ROAD AND STRUCTURE DESIGN <br />Sargent will prepare the design to improve the road by removing the existing culverts and installing new <br />structures. Sargent Engineers will prepare the design for the structures and the road. The design will <br />follow the requirements of the AASHTO LRFD Bridge Design Specifications and the WSDOT Local Agency <br />Design Guidelines. <br />It is assumed that stormwater drainage improvements will not be necessary. It is also assumed that the <br />road will not be widened at each site. <br />A preliminary plan for the improvement for each site will be prepared and reviewed with the County. Once <br />the County approves of the proposed improvement, than final design will be performed for each site. The <br />design will include the design of the road, the structure, and the proposed method of construction. <br />PLANS <br />Sargent Engineers will prepare the plans for the replacement of the structures. The plans will follow the <br />format that the County desires. They shall include at a minimum: <br />Page 4 <br />