Clean Water Current

(July 10, 2020) – In a series of comment letters, NACWA asked EPA to consider aquatic impacts of pesticides and to improve label language for pesticide products.

The Association’s July 6 comments on pesticides used in pet flea control products recommended mitigation measures to control the impacts of the pesticides on publicly owned treatment works (POTWs) and their receiving waters. NACWA asked EPA to consider eliminating the use of permethrin and bifenthrin in pet flea shampoos, since less toxic alternatives are available. For other pyrethroids used in pet products, NACWA requested that EPA consider the risks posed by each individual chemical, rather than all pyrethroids as a group, since the individual chemicals present different levels of risk for POTWs. 

NACWA also submitted comments on chemicals used in swimming pools and fountains: chlorine gas, terbuthylazine, and halohydantoins. Since swimming pool chemicals can potentially interfere with the biological processes used to treat wastewater if discharged into sewers, or have adverse aquatic impacts if discharged into storm drains, NACWA recommended that EPA use label language that states, “[b]efore draining a treated pool, spa, or hot tub, contact your local sanitary sewer and storm drain authorities and follow their discharge instructions.” EPA has adopted this label language for other chemicals used in swimming pools. 

In addition, NACWA submitted comments on the biological evaluation of carbaryl, since this evaluation will likely set a precedent for future evaluations conducted to comply with the Endangered Species Act. NACWA asked EPA to include the presence of carbaryl and other pesticides in POTW effluent in its biological evaluations by identifying pesticide uses and pathways to the sewer system, and by using existing EPA models. 

NACWA supported the comments of the Bay Area Clean Water Agencies (BACWA), which has been advocating for improved consideration of pesticide impacts to POTWs. NACWA will continue to work with BACWA to address this issue. NACWA members with questions or information about pesticide impacts should contact Cynthia Finley, NACWA’s Director of Regulatory Affairs.