Sanitary Sewer Overflow Due to Tropical Depression Bertha Rain Event

MOORESVILLE, NC – On May 28, the Town of Mooresville experienced very heavy rains and flash flooding associated with Tropical Depression Bertha. Unofficial estimates indicate that anywhere between 3” to 4” of rain fell during a 4-hour period. As a result, the Town had a bypass of untreated wastewater. The bypass was 15,000 gallons
at the Rocky River Wastewater Treatment Plant, 369 Johnson Dairy Road, which discharged to Dye Creek Branch.

As is typical of discharges during extreme storm events, a sizable portion of the untreated wastewater was rainwater that had entered the system near swelled creeks or in low lying areas. The spill was not of a magnitude to cause immediate danger to human health or to the environment.

North Carolina General Statute 143-215.1C requires the owner or operator of any wastewater collection or treatment system to report when an untreated wastewater discharge of 1,000 gallons or more reaches surface waters. The North Carolina Department of Environmental Quality, Water Resources Division was notified of the spill on May 28 and is reviewing the incident.