Client: Clearfield Municipal Authority
Year Completed: 2010
Project Cost: $6,500,000
The Clearfield Municipal Authority maintains a water supply dam on Moose Creek. Because of regulatory non-compliance, the water authority deactivated this unfiltered water source in 1990. To provide a supplementary water source for its service area (14,000 population), the authority used its long standing consulting engineer, Gwin, Dobson & Foreman to design a filtration system using the best available technology. The resulting membrane treatment system is one of the largest plants to employ microfiltration in the northcentral region of Pennsylvania.
The project included the following:
- Extensive pilot testing of membrane filtration system of a Pall Corporation ARIA Model AP-3 membrane cartridge technology.
- The microfiltration (MF) system achieves 6-log removal of protozoans (giardia and cryptosporidium), filtrate turbidity less than 0.1 NTU and 95% MF system recovery.
- The membrane filtration process has a module capacity of 1 mgd. The plant also includes an extensive chemical feed system (potassium permanganate, liquid chlorine, caustic soda, corrosion inhibitor and fluoride), baffled clearwell (sized for 3-log inactivation), filtrate waste storage/recycle tank, sludge drying beds and finish water pumping system.
- Blending and treatment of groundwater from Moose Creek Well No. 3 including oxidation, microfiltration and the off-gassing of residual hydrogen sulfide.
- The plant employs an ultraviolet disinfection system for pathogen deactivation and DBP control.
- Design of control building including chemical feed and storage systems, mechanical and process piping systems, MF “clean-in-place” chemical cleaning system, hot-water boiler system (for MF make-up cleaning water), control room and laboratory.
- Sophisticated computer instrumentation, control and monitoring system for MF operation.
- Electrical work, lighting systems, power wiring and standby power system.
GD&F also provided all construction administration, inspection and Pennvest documentation. Although a sophisticated water treatment system, the microfiltration process is one of the easiest to operate and maintain. The water authority expressed complete satisfaction with the function and workmanship of the project.