About 30,000 gallons of partially treated wastewater overflowed from the Town of Millsboro Waste Water Treatment Facility and reached the Indian River on February 26, 2026, according to the Delaware Environmental Release Notification System. The facility had a spill just last month.

The discharge happened at the facility at 361 E. State St. The wastewater flowed onto the ground at the plant and into the Indian River.

The facility has conducted clean up on the ground and is working with the Delaware Department of Natural Resources and Environmental Control (DNREC) ground water section, according to the report. DNREC is investigating the incident.

In January, the Town of Millsboro confirmed that a broken pipe led to 25,000 gallons of wastewater spilling. The town said the spill was discovered during routine maintenance on a sewer gravity collection system just north of the plant. 

As a result of that spill, DNREC had to issue an emergency closure of the Indian River Bay to all bivalve shellfish harvesting, including clams and mussels.

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