Riverhead cleans up stinking mess after July 4 storm triggers 20,000-gallon sewage spill

The Riverhead Sewer District headquarters has been cleaned up after a power outage during the July 4 storm caused biosolids tanks at its treatment plant to overflow, officials said.

The Riverside Drive facility lost power that night, automatically triggering its backup generators, according to a town news release. The building remained on generator power until Tuesday, July 7, when the utility company restored service.

However, a nasty spill greeted Sewer District personnel when they returned to work Tuesday morning after the holiday weekend.

They found that when power was restored, the permeate pumps that regulate the biosolids tanks faulted, causing 20,000 gallons of partially treated sewage to overflow onto Sewer District property. The spill reached a facility roadway, nearby drywells and adjacent Sewer District-owned woods.

Workers sprang into action immediately and reset the pumps, stopping the spill within roughly 30 minutes, according to officials.

After further investigation, sewer department employees found that the transformer for the alarm system had failed, disabling the notification system that would have typically sent an alert about the issue.

Suffolk County Health Services and the state Department of Environmental Conservation were notified and all required reports were filed in a timely manner, officials said.

County health officials were also on site during and after the cleanup. Satisfied with the remediation efforts, they determined that no further action was required at this time.

Superintendent Tim Allen said Monday that the contained spill remained entirely within sewer district property.

“My team vacuumed the free liquid from the drywells and roadway and delivered to the on-site Scavenger Waste Plant,” Mr. Allen said in a statement. “We spread lime and disinfectant to the affected areas and have performed a thorough check of all our systems to make sure this type of event doesn’t happen in the future.” 

Officials said questions or comments can be directed to Mr. Allen at 631-727-3069.