Basin Analysis + Interceptor
Knightdale Sanitary Sewer Basin
Following the proposal of a 600,000 square foot commercial development, the Town of Knightdale required a sanitary sewer analysis to determine the wastewater infrastructure necessary to serve the proposed development and additional build-out flows within the sewer basin. It was confirmed during the analysis that a new interceptor would need to be installed crossing under the future Interstate 540 Northern Expressway, which posed some design and NCDOT coordination challenges.
McAdams was contracted to analyze a 1,342-acre sewer basin in the Town of Knightdale and design a sanitary sewer interceptor. McAdams evaluated the build-out scenario of the basin and presented the results to the Town of Knightdale. Based on the results of the analysis, McAdams designed 12,414 linear feet of 8 to 18-inch sanitary sewer that discharges to an existing interceptor downstream, a portion of which would pass under the future I-540 Northern Expressway. Careful coordination with NCDOT was required so that the depth and alignment of the interceptor would coincide with the future I-540 design. Upon completion of the design efforts, McAdams’ staff obtained the necessary construction document approvals and permits from NCDENR and encroachment agreements from NCDOT. McAdams also prepared the easement plats for the interceptor easement. In addition, the McAdams design team conducted regular inspections of construction while providing guidance to the Town and contractor for successful completion of the project.