Solution: The City of Marshfield, Wisconsin, required concrete manholes with exceptionally smooth, precise flowlines—performance other suppliers couldn’t deliver. County Materials met the challenge with Prima Base™ Monolithic Manholes, eliminating the need for grinding and ensuring dependable, watertight performance for this critical sanitary sewer system.
Delivering Smooth, High‑Performance Flowlines for Municipal Sewer Systems
The City of Marshfield, Wisconsin, maintains a rigorous inspection program for its sanitary sewer network, requiring manhole bases that deliver exceptionally smooth flowlines to support debris-free operation and reduce maintenance. Historically, contractors and city crews were required to grind and polish precast flowlines to achieve the smooth finish needed for proper hydraulic performance.
In 2025, the city selected County Materials’ Prima Base Monolithic Manhole Base for new sanitary sewer installations. Manufactured to ASTM C‑478 specifications, Prima Base components feature precisely cast channels, inlets, and outlets designed and manufactured for consistent, watertight alignment. Upon inspection, the City of Marshfield reported that the flowlines were remarkably smooth and required no additional grinding, polishing, or coating—streamlining installation and improving long-term reliability.
Contractors also noted an added installation advantage: the smooth, accurately formed flowlines allow PVC sewer pipe to be temporarily inserted beyond the typical shoulder point and then withdrawn to seamlessly connect to existing lines. This flexibility supports faster installations and minimizes disruptions to ongoing sewer maintenance work.
Project Highlights:
This project showcases County Materials’ ability to deliver precast concrete sewer solutions that enhance hydraulic performance, minimize labor needs, and reduce long‑term maintenance demands.
