Laserfiche WebLink
CppES ... 70, <br />IaTTITAS COUNTY <br />KXr=XgVAB CD <br />DEPARTMENT OF PUBLIC WORKS <br />TASK 3.50— Feasibility Review <br />Perform a high level review to determine if a 60 foot bridge span is feasible to eliminate <br />need for cast -in-place concrete abutments. Evaluate existing design for using temporary <br />detour bridge for 1 year rather than originally anticipated 3 month duration. <br />TASK 4 HYDRAULIC DESIGN <br />Watershed Science & Engineering (WSE) will provide hydraulic engineering services for the Big <br />Boulder Creek Bridge Replacement Project in Kittitas County, Washington. WSE will lead the <br />hydraulic engineering portions of the project which will include completing the following tasks. <br />TASK 4.10 — Data Collection and Review <br />WSE will collect and review existing data and information needed to complete the hydraulic <br />investigation. Data will include but not be limited to topographic maps including LiDAR data, <br />historical aerial photos, flood data, bridge maintenance records, and anecdotal information on <br />past flood events from County maintenance staff. <br />Assumptions: <br />• County will supply relevant data they possess <br />TASK 4.20 — Site Inspection <br />WSE will conduct a one -day field inspection to examine the crossing and Big Boulder Creek. <br />WSE will examine hydraulic and geomorphic characteristics, sediment transport, debris flow <br />potential, lateral erosion, and scour. <br />Assumptions: <br />NTP is received in time to allow WSE to visit the site before snow fall. <br />TASK 4.30 — Channel Survey <br />WSE will survey up to eight cross sections and a longitudinal profile of the stream channel as <br />part of the site inspection task above. WSE will merge the stream channel data with the <br />County's survey to develop a single topographic base map required for the hydraulic <br />investigation. <br />Assumptions: <br />• County will or has collected detailed topographic data within the road right-of-way. <br />TASK 4.40 — Hydrology <br />