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4. DELIVERABLES <br />4.1. One (1) JARPA package for delivery to USACE, WDFW, and WDOE <br />4.2. One (1) Local Agency correspondence for each permit/exemption. <br />TASK 7 HYDRAULICS <br />1. Data Collection <br />1.1. Collect existing data and information needed for the hydrologic, geomorphic, hydraulic <br />and scour analysis of the proposed Manastash Creek Bridge. Request and collect <br />available information such as: <br />1.1.1. Existing topography <br />1.1.2. Aerial photos <br />1.1.3. Bridge inspection records <br />1.1.4. Bridge plans <br />1.1.5. Previous hydraulic/hydrologic studies <br />1.1.6. Anecdotal information on past flood events <br />2. Field Reconnaisance <br />2.1. Conduct a field inspection to examine the characteristics of the creek, bridge, and <br />surrounding riparian corridor with respect to hydraulic, erosion, and scour processes. It <br />will be beneficial to meet with the COUNTY surveyors on site during the site <br />reconnaissance to discuss where additional survey may be needed to support the <br />hydraulic and scour analysis. Field measurements will include: <br />2.1.1. Characterizing sediment size <br />2.1.2. Estimating channel/floodplain roughness <br />2.1.3. Bridge measurements <br />2.1.4. Assessment of existing scour protection <br />2.1.5. Documenting lateral and longitudinal erosion. <br />2.1.6. Identification of high water marks <br />2.1.7. Other relevant information to aid in assessment and design of the proposed water <br />crossing. <br />2.2. Determine appropriate bridge span and potential scour countermeasures for the <br />proposed crossing. <br />3. Hydrology <br />3.1. Hydrology for Manastash Creek will be determined by reviewing: <br />3.1.1. Prior studies <br />3.1.2. USGS regression analysis <br />3.1.3. Basin comparison with nearby watersheds and anecdotal information provided by <br />COUNTY staff from previous high-flow events. <br />3.2. Conduct analyses to determine the discharges for the 2-, 10-, 25-, 50-, 100-, 200-, and <br />500 -year flood events. <br />4. Geomorphic Reach Assessment <br />