Mosquito Abatement Spraying to Begin in Rock Springs on Monday

Mosquito abatement spraying will begin in Rock Springs beginning on Monday.

ROCK SPRINGS — Over the next few weeks city personnel will be spraying in areas of the city using a truck mounted aerosol sprayer as The City of Rock Springs begins its mosquito abatement program.

Spraying will be conducted between Monday July 8, 2019 and Friday July 12, 2019 in the following areas:

  • The Cemetery
  • Sweetwater Creek
  • Bitter Creek from East I-80 Interchange to the Waste Water Treatment Plant
  • The area around Bunning Park
  • The Wetlands Park area by Smith’s
  • Killpecker Creek along Springs Drive and Community Park Drive

Further spraying needs will be evaluated throughout the summer.

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The project uses a spray formulation that contains the pesticide product, Biomist to control the mosquitoes. The active ingredient in Biomist is permethrin, a second-generation synthetic pyrethroid that is classified as a slightly toxic pesticide by the EPA.

These insecticidal compounds are either harvested directly from or based upon substances in the chrysanthemum plant.

Mosquito control applications of permethrin do not pose a significant risk to people or pets due to the low toxicity of the spray and small amount used to control mosquitoes. As with any pesticide, people, and pets should minimize exposure.

If residents see the spray truck next to their yards, they are advised to go indoors, close windows and turn off cooling units for a few minutes while the spray dissipates. 

This project is part of an overall effort to control mosquitoes in the City of Rock Springs. In June, Altosid XR larvacide pellets containing methoprene were put into the stagnant water areas of the Bitter Creek and Killpecker Creek through town.

Altosid XR larvacide pellets were also placed in some of the ponds at the golf course and in the City flood detention ponds. Altosid attacks the mosquito larvae as it develops, prevent it from reaching adulthood and interrupting the growth cycle and lasts approximately 150 days.

West Nile Virus

While enjoying activities or working outdoors during Wyoming’s warmer months, residents should avoid mosquitos because they can spread potentially serious disease, according to the Wyoming Department of Health. Mosquitos spread West Nile virus (WNV) when they feed on infected birds and then bite people, animals and other birds.

The “5 D’s” of West Nile virus prevention include:

  • DAWN and DUSK – Mosquitos prefer to feed at dawn or dusk, so avoid spending time outside during these times.
  • DRESS – Wear shoes, socks, long pants and a long-sleeved shirt outdoors. Clothing should be light-colored and made of tightly woven materials.
  • DRAIN – Mosquitos breed in shallow, stagnant water. Reduce the amount of standing water by draining and/or removing.
  • DEET – Use an insect repellent containing DEET (N, N-diethyl-m-toluamide). When using DEET, be sure to read and follow label instructions. Other insect repellents such as Picaridin (KBR 3023) or oil of lemon eucalyptus can also be effective. 

WNV activity is tough to predict. In Wyoming last year, 41 human WNV cases, including one death, were reported. Since WNV first appeared in Wyoming in 2002, reported human cases each year have ranged from two with no deaths to 393 and nine deaths.

More information on West Nile virus is available on the web at Questions about the Rock Springs mosquito control project may be directed to Rock Springs Fire Chief Jim Wamsley at 352-1475.