West Nile Virus Surveillance Program

Wastewater Treatment Operators

Is my wastewater treatment plant a mosquito-breeding site?

Wastewater treatment plants could provide suitable areas for mosquitoes to breed. The nutrient-rich water in polishing ponds, used by some wastewater treatment plants is an ideal breeding area for mosquitoes, including those known to carry West Nile virus.

How can I prevent mosquitoes from breeding?

There are many ways to eliminate mosquito-breeding areas at wastewater treatment facilities. Maintenance of wastewater facilities should include filling ruts and low spots that result from heavy traffic areas with stones or other filler. This will help eliminate puddles and other areas of standing water.

In situations where eliminating mosquito-breeding areas is not a practical alternative, larviciding is the most effective control technique. Several larvicides are well suited for farms, including Bacillus sphaericus. B. thuringiensis israelensis (B.t.i.), Temephos, growth regulators, oils and mono-molecular films. These larvicides can only be applied by certified pesticide applicators. An applicator can help you to determine which product would best suit your situation, and what type of control activities should be conducted.

EPA - Pesticides and Mosquito Control

Public Health Page