Laserfiche WebLink
DISCUSSION: <br />Adverse flooding impact to area residents is predicted by culvert replacement. Our initial <br />hydraulic assessment assumes all roadside ditches remain open. Both the FHWA and <br />area residents question our assumption of open culverts during a 100 year flood event. <br />As a final flood assessment, PW has recently directed a final assessment assuming all <br />culverts plugged and the bridge installed (EXHIBIT 3). Adverse impacts appear <br />unavoidable keeping the creek in roadside ditching. <br />FISCAL EMPACTS: <br />Owing to the increased need for hydraulic and survey work, PW will likely exceed <br />original cost share obligations delivering the project. Impacts to project costs are not <br />available at this time. <br />ATTACHMENTS: <br />Exhibit 1: Flood rise analysis (08-28-2019) <br />Exhibit 2: Letter and flood analysis sent to WDFW 09-20-2019 <br />Exhibit 3: Flood rise analysis all culverts plugged <br />Page 2 of 5 <br />PUBLIC WORKS BOARD OF COUNTY CONMSSIONERS WORK SESSION STAFF REPORT <br />