In 2003-2004, the Maumee River WWTP was expanded again to increase the design / peak capacity by 7.5/17.3 MGD (Plant total is now 22.0/47.3 mgd). These improvements were constructed as a totally separate liquid treatment train called the West Plant. The former Plant B is now called the East Plant.
The West Plant treatment includes influent screening and grit removal for preliminary treatment, a primary clarifier, chemical addition for phosphorus removal, two two-pass aeration basins for activated sludge treatment, two final clarifiers, and an ultraviolet disinfection system. The new West Plant was constructed with the future capability to be expanded to a design / peak capacity of 15.0/34.5 MGD.
In addition to the construction of the new West Plant, the County also made several improvements to the East Plant, the Anaerobic Digesters, Sludge Storage Facilities, and the Administration Building. The improvements to the East Plant included replacing the old centrifugal blowers with new, energy-efficient single-vane centrifugal blowers; replacing the coarse bubble diffusers in the aeration tanks with fine bubble diffusers; replacing the old chlorination / dechlorination system with and Ultraviolet Disinfection system; and, installing bio-scrubbers for odor control at the aerated grit chamber and raw sewage pumping station. The other changes to the MRWWTP included increasing the Anaerobic Digester gas line sizes, adding an additional dewatered sludge storage pad, and adding new offices, conference rooms, and storage space in the Administration Building.