Lakeshore Drive Drainage Improvements
In 2015, Natrona County Roads & Bridges Department (NCRB) hired WLC Engineering, Surveying, and Planning to design drainage improvements along a portion of Lakeshore Drive. The project area experienced severe thunderstorms which delivered large quantities of silt to Alcova Reservoir completely filling the existing culvert crossings and depositing several thousand cubic yards of silt into the reservoir rendering several existing boat docks unusable. WLC analyzed the three contributing drainage basins to estimate peak runoff for the 10, 25, 50 and 100 year return periods at each crossing of Lakeshore Drive. The resulting project installed three structures to improve drainage in this area. WLC designed twin 48” culverts in a location that did not have culverts installed previously. The channel slope and geometry upstream and downstream of this crossing is designed to allow maximum channel velocities and fit the largest culvert diameter allowable. The other two crossings removed the existing 36” culverts and replaced them with 8’X8’ RC box culverts. These structures convey peak runoffs in excess of the 100 year peak flows. NCRB wanted structures at these crossings that would allow crews to easily remove silt from the structures. Our design utilizing 8’X8” box culverts allows a skid steer loader to enter the culverts and remove any silt or debris that is deposited in them. In addition to the design of the crossing structures, WLC provided bidding services, construction staking, material testing, and contract administration services for the County.