Originally built in 1951, the Roanoke Regional Water Pollution Control (WPC) Plant provides tertiary treatment of sewage from all jurisdictions in the Roanoke Valley. A drop of sewage entering the facility takes approximately 19 hours to move through all levels of the liquid treatment process before the treated water can be safely discharged to the Roanoke River. All along the way, more than 3,000 lab tests are conducted each month to verify that the treatment process is meeting or exceeding water quality standards.
While the facility’s daily treatment capacity is permitted at 55 million gallons, average daily treatment is currently about 37-million gallons per day. However, during more significant wet weather events, flow coming into the facility can increase to as much as 137 million gallons in one day.
Started in January 2013, the Peak Flow Enhancement Project will allow the Roanoke Regional Water Pollution Control Plant to treat and discharge more flow during high river stage events. The project involved construction of a new chlorine contact basin, new effluent screw pumps and modifications to the Biological Aerated Filter (BAF).
While pathogens are removed throughout the treatment process, the final step of chlorination, and then neutralizing that chlorine, guarantees the quality and safety of the water discharged into the Roanoke River. The four new chlorine contact basins, which can collectively hold over one million gallons, provide additional treatment capacity and offer system redundancy for the original basins. The new basins are 9.33-feet deep and are 140-feet long.
The four new Archimedes screw pumps at the end of the basins can each lift 40 mgd of flow. These 300 hp pumps will be used when river stages are elevated and gravity feeding the treated flow into the river is not effective.
The third component of the project, the Biological Aerated Filter (BAF), has been modified to provide treatment from the equalization basins which enhances the overall peak treatment capacity of the facility and extends the storage capacity during wet weather events.
The Authority and its partner jurisdictions of Roanoke City, Roanoke County, Botetourt County, the City of Salem and the Town of Vinton have made past investments to improve the sewer collection system, enhance flood protection within the plant and maximize prior investments by gaining additional treatment capacity. This most recent project provides redundancy in the final steps of treatment and will allow the facility to continue exceptional levels of treatment during high river stage events in the Roanoke River.
Since 2012, the Roanoke Regional WPC Plant has been Platinum Rated, the highest honor given by the National Association of Clean Water Agencies. In total, the facility meets over 7,000 compliance points annually with no exceptions granted in the permit structure, one of the most stringent discharge requirements in the Commonwealth of Virginia.
Additional information about the Western Virginia Water Authority is available at www.westernvawater.org.