RICHMOND, Va., May 12, 2003 — USFilter's General Filter Declining Rate MULTIWASH® CenTROL® filters have been selected as part of a four-phase expansion of the Henrico County Water Reclamation Facility.  The plant, which serves the Richmond, Va. area, will expand from 45 million gallons per day (mgd) to 75 mgd average annual flow to accommodate explosive new residential growth in Henrico County. 

Two MULTIWASH® CenTROL® filters will be added to an existing four units.  Once installed, the expanded filter system will be capable of treating up to 150 mgd at peak capacity.

The original MULTIWASH® CenTROL® filters were installed in 1996 and replaced a traveling bridge filter system that was unable to meet plant operational requirements.  The MULTIWASH® CenTROL® design was selected based on reduced footprint, demonstrated backwash performance and experience base.  The filters utilize a 48 in. bed depth of mono-media anthracite.  With the new units in place, Henrico County will be the largest MULTIWASH® CenTROL® installation in both size and flow capacity.

Each CenTROL® filter includes four filter cells clustered around a central control column and influent distribution flume to minimize footprint.  All cells are connected in a common effluent chamber, making it possible to backwash with water from in-service cells.  The MULTIWASH® process is sustained, simultaneous air-water backwashing to reduce backwash water rate and provide guaranteed clean media after each backwash.  Similar systems have been installed at hundreds of installations around the world.

The filter expansion is part of the Phase 4 facility expansion designed by Hazen and Sawyer, PC (Raleigh, N.C.) and Dewberry & Davis, Inc. (Richmond, Va.).