Project Spotlight: Contentnea Metropolitan Sewerage District Wastewater Treatment Plant Upgrades

On Thursday, February 18th, the Eastern Professional Wastewater Operators Committee (PWOC) was hosted by the Contentnea Metropolitan Sewerage District (CMSD) with a catered lunch from The Skylight Inn and provided by The Wooten Company. The lunch was followed by a tour of the District’s wastewater treatment plant led by Chuck Smithwick, District Manager, CMSD and Charlie Davis, P.E of The Wooten Company. We felt that this was a great excuse to showcase some of Mr. Smithwick and Mr. Davis’ hard work on this great project.

The CMSD plant began operation in 1976 as a 2.0 MGD facility and was recently expanded and upgraded to 3.5 MGD. The current plant includes screening, grit removal, 5-Stage BNR, tertiary filtration, and UV disinfection prior to its discharge to the Contentnea Creek. Aerobic sludge is dewatered with Huber Incline Screw Presses which is transported off-site for composting and also land applied (in liquid form) to CMSD owned land application sites.

The CMSD is comprised of Pitt and Lenoir Counties in North Carolina and maintains pump stations in Winterville, Ayden, along Highway 11 and in Grifton. A few years ago, the decision was made to perform improvements to these stations and also perform an upgrade to its 2.85 MGD wastewater plant.

For this, The Wooten Company provided a full range of engineering services that included a study and report phase, design, bidding and negotiation assistance, construction contract administration, construction observation and post-construction operation and maintenance training. The plant’s construction occurred in 3 phases over a 3 ½ year period and involved over $30 million dollars in grant/ loan funding from four separate funding agencies. The project included the design and installation of new influent headworks, denitrification filters, an Ultra-Violet disinfection system, a post-aeration system and all the necessary piping modifications for flexible and improved plant operation. Since the denitrification filter was placed online, the plant’s effluent Total Nitrogen (TN) has consistently averaged around 1 mg/l allowing CMSD to be well within their TN Discharge Limit of 32,000 lb/yr.

Additionally, the improvements required the construction of an effluent outfall for the discharge of effluent to the Contentnea Creek, a tributary of the nutrient-sensitive Neuse River. Mr. Davis and his staff provided grant administration for the Clean Water Management Trust Fund and NC Rural Center funding assistance for the project.