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be needed to support the hydraulic and scour analysis. Field measurements will <br />include: <br />2.1.1. Characterizing sediment size <br />2.1.2 . Estimating channel/floodplain roughness <br />2.1.3. Culvert 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 ofthe proposed water <br />crossing. <br />2.2. Determine appropriate bridge span length and potential scour countermeasures for the <br />proposed crossing. <br />3. Hydrology <br />3.1. Hydrology for Lick 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 />SOD-year flood events. <br />4. Geomorphic Reach Assessment <br />4 .1. Conduct a rapid geomorphic analysis using newly obtained survey information, <br />geotechnical reports, aerial photos, and findings from the field reconnaissance. The <br />purpose of this assessment is to determine if there have been significant geomorphic <br />changes over time which will need to be accounted for in the design of the proposed <br />water crossing and potential creek realignment and to determine if there has been a <br />historic creek alignment similar to the one being proposed. <br />5. Hydraulics <br />5.1. Perform hydraulic modeling to ascertain the hydraulic characteristics necessary to <br />support the design of the new bridge crossing, creek realignment and potential scour <br />countermeasures for the protection of the roadway prism. The hydraulic model will be <br />developed using topographic data collected by the COUNTY-supplied topographic <br />survey in conjunction with the CONSULTANT bridge design. The hydraulic model <br />results can be used to support permitting to show the proposed water crossing meets <br />WAC 220-660-190. <br />6. Bank Stability Assessment and Design <br />6.1. Examine stability of the existing scour protection and river banks utilizing various <br />design manuals such as, Integrated Streambank Protection Guidelines (ISPG), HEC -18, <br />HEC-23, etc. <br />6.2. Coordinate with COUNTY staff to identify proposed measures that are acceptable from <br />a channel stability and habitat perspective .