The Contentnea Metropolitan Sewerage District (CMSD) serves the member towns of Winterville, Ayden and Grifton of Pitt and Lenoir Counties. The original wastewater treatment plant was constructed in the mid seventies as a two-stage activated sludge process. While district staff consistently operated the facility to its maximum potential, there came a point where enhanced nutrient removal capability was a must to meet strict effluent limitations in the Neuse River Basin. Construction of improvements to the CMSD wastewater treatment plant occurred as a two-phased process.
Phase 1 included a new headworks facility complete with mechanical screen w/ 1/4-inch openings and screenings compactor, vortex grit removal system and Parshall Flume; new filter lift pump station; new four cell deep bed denitrification filter system; new three bank UV disinfection system; new post aeration tank and new effluent outfall to Contentnea Creek.
Phase 2 included expansion of the plant capacity to 3.5 mgd and consisted of the following major components: new five-stage biological nutrient removal (BNR) activated sludge process; new secondary clarifiers; new RAS/WAS pump station; sludge handling improvements consisting of a new sludge dewatering facility with dual screw presses; and modifications to existing basins for flow equalization and additional sludge stabilization/holding facilities.
I am most satisfied and proud of our WWTP expansion/upgrade as this has proven to be a very efficient and operator friendly design. This facility has gone from the worst performing facility to the best performing facility in the Neuse River Basin Association.
— Chuck Smithwick, CMSD