Inadvertent discharge of partially treated wastewater

HARLINGEN, Texas - Due to heavy rains from Hurricane Beryl on July 12, partially treated wastewater was inadvertently discharged between 1 and 2:30 p.m. The U.S. Immigration and Customs Enforcement Port Isabel Special Processing Center's wastewater treatment plant experienced a large infiltration of storm water. The maximum daily output is 160,000 gallons of treated wastewater. The storm water contributed to the plant discharging about 250,000 gallons of partially treated wastewater, caused by storm water that overflowed from a nearby ditch into the return drain of the sludge roll-off container.

In response, ICE notified the Texas Commission on Environmental Quality, the Texas Department of Parks and Wildlife, and the Laguna Atascosa National Wildlife Refuge. After consultation, it was determined that disinfection of the area affected by the overflow discharge was not recommended, because chemical disinfection could have been more harmful to wildlife than the risk posed by the partially treated wastewater. Instead, it was determined that frequently monitoring E. coli bacteria levels was the optimum approach. These levels have been tested, and they have remained well within the requirements established by the Texas Commission on Environmental Protection.

As part of its ongoing resilience efforts, ICE will prevent such incidents in the future by fabricating and installing covers over the return drain to limit any storm water infiltration into the wastewater treatment plant and will also expand, clear and dig alternative drain ditches to divert excessive storm water away from the plant.