Health Department to Treat Stormwater Catch Basins for Mosquitoes
Published on May 19, 2025
PITTSBURGH – The Allegheny County Health Department (ACHD) will be treating stormwater catch basins in the City of Pittsburgh, as well as the boroughs of Bellevue, McKees Rocks, Millvale, Mt. Oliver, and Wilkinsburg for mosquitoes, starting Monday May 19.
“Catch basins are favorable breeding habitats for mosquitoes in urban environments,” said ACHD Housing and Community Environment Vector Control Specialist Nick Baldauf. “The mosquitoes that breed in catch basins have the potential for spreading disease, such as West Nile Virus, to residents.”
The treatments will take place from May 19-23 and June 2-6 between the hours of 4:00 PM and 9:00 PM, but may be postponed if heavy rains are in the forecast. ACHD will be treating approximately 14,000 catch basins throughout the city of Pittsburgh, and the boroughs of Bellevue, Millvale, McKees Rocks, Mt. Oliver, and Wilkinsburg, which have had a history of West Nile activity in previous years.
This is the 24th consecutive year that ACHD will be conducting these treatments.
The product being used, Altosid XR, is non-toxic to people, pets, plants, and other aquatic life. Small blocks of the product will be deposited in the catch basins and treated basins will be marked with bright green paint.
Catch basins that hold water are breeding grounds for mosquitoes during the summer. Basins will be treated with a product that targets mosquito larvae so there will be fewer flying, biting adults with the potential to transmit diseases to people and pets.
“Residents can greatly reduce the mosquito population by eliminating and treating potential breeding sites on their properties,” said Baldauf. “Mosquitoes can breed in as little as a half inch of stagnant water, so be sure to pay close attention to potential breeding sites like water in tires, tarps, unused swimming pools, corrugated piping, buckets, and clogged gutters.”
Inexpensive, but effective, natural pesticides like what the ACHD uses are available at hardware stores, home improvement centers, and online.
To report potential mosquito breeding sites, contact the Health Department’s Housing and Community Environment Program by calling 412-350-4046 or through the ACHD website.
Media inquiries may be directed to Ronnie Das,
Public Information Officer for the Health Department,
at ronnie.das@alleghenycounty.us or by phone at 412-578-7991.