An additional expansion may be needed to meet projected treatment needs beyond 2020. The groundwork for the next expansion was laid-out during the 2003-2005 project when the West facility was constructed with built-in expandability to a total plant capacity of 30 million gallons per day (MGD).
The projected treatment equipment needed for the future West facility expansion includes a third influent screen, a second vortex grit removal unit, additional raw sewage pumping, a second primary clarifier, another two-pass aeration tank, a third final clarifier, a second centrifuge and new dewatering building adjacent to the sludge storage pads, additional RAS and WAS pumps, and four additional banks of UV bulbs. Additional anaerobic digester capacity will also likely be required in the next expansion.
The current long range plan calls for the construction of two additional primary digesters adjacent to the existing tankage on the south side.