The Department of Natural Resources and Environmental Control was informed today by Tidewater Utilities, Inc. that the Lewes wastewater treatment plant was back online and had resumed normal treatment of effluent following a Dec. 18 system malfunction at the plant. Tidewater Utilities informed DNREC Saturday evening that treatment membranes contaminated during an automated backwashing process which caused the malfunction had been replaced, ending the plant’s system bypass operation that discharged partially-treated effluent for nine days into the Lewes-Rehoboth Canal and the lower Delaware Bay.
Installation today of the new and highly-effective treatment membranes by Tidewater Utilities enabled the Lewes WWTP to treat incoming flow as normal and discontinue bypass pumping. During the bypass operation, DNREC staff was onsite at the plant directing Tidewater Utilities’ sampling of the partially-treated effluent for bacteria levels and monitoring the sampling for possible health risks.
When the system malfunctioned and the bypass operation began, DNREC also ordered immediate closure of shellfish harvest areas in the lower Delaware Bay due to health concerns from partially-treated effluent. The closure of shellfish harvest areas will continue for a 21-day period from the time the bypass situation ended and Lewes wastewater treatment plant’s effluent met required discharge standards. The closure ordered by DNREC is based on US Food and Drug Administration (FDA) Guidelines under the National Shellfish Sanitation Program, and provides adequate public health protection for pathogens of concern, including viruses. The closure applies only to clams, oysters and mussels – crabs, conch and fish species are not affected