In Medford, as in most cities, a large percentage of used water moves from homes, businesses, institutions and industries via a sanitary sewer system to a central point; the wastewater treatment facility. The purpose of the wastewater treatment facility is to remove the wastes from the water prior to discharging the flow into the Black River. In essence, we must purify the wastewater to protect the waterways for public and private uses downstream of the facility.
The removal of wastes is accomplished through physical, biological and chemical means; resulting in a treated effluent. Wastewater sludge, which is the solids by-product of the biological process, is applied to agricultural land as a nutrient supplement.
The Medford Wastewater Treatment plant is designed to treat a flow of 1.45 million gallons per day (mgd) receiving an average of 1.01mgd, while serving a population of nearly 4,400. Approximately 27% of the flow originates from industrial sources. The wastewater treatment plant does an exceptional job of pollutant removal, consistently removing more than 99% of the biochemical oxygen demand, suspended solids, and ammonia from the incoming wastewater. Major treatment processes include preliminary treatment, activated sludge biological treatment, final clarification, tertiary filtration, seasonal chlorination and dechlorination, and cascade aeration prior to discharge to the Black River. Sludge is aerobically digested, dewatered in a belt press, and land-applied.
In 1988 the plant underwent a major renovation. In 1990 a chlorination and dechlorination building was added and in 1999 ferric chloride phosphorus removal was added.
In 1997 the plant received a Region 5 United States Environmental Protection Agency, Operation and Maintenance (O&M) Award for having the best operated wastewater treatment facility in the Medium-Advanced category. Medford was one of six communities to receive an O&M award that year. The award is based on the following achievements:
- An excellent permit compliance record during the past two years
- Precise process control, which has decreased sludge production and includes microscopic examination of the biological process
- Reduction in operating costs of the lift stations by installing larger pumps and making other modifications
- An outstanding laboratory program, which has been recognized for excellence by the WI DNR
- Utilization of a small, highly competent staff to run the facility