PSA – Watertown 2022 Mosquito Control Program Information | Local News

The City of Watertown is preparing its mosquito control program for the 2022 season. The program is designed to reduce the threat of West Nile virus which is transmitted to humans through the bites of infected mosquitoes.

There are 43 known species of mosquitoes in South Dakota and only nineteen are known vectors of West Nile virus. It is estimated that less than 1% of mosquitoes are infected with West Nile virus. And less than 1% of people bitten by infected mosquitoes will become seriously ill. The chances of you being infected with the disease are very low, but even one case of West Nile virus is considered one too many.

Part of the city’s mosquito control program is to control the mosquito population while they are in the waterborne larval stage before they turn into the annoying flying mosquitoes we have all become familiar with. This is accomplished by eliminating areas of standing water or treating these breeding areas with a larvicide.

The City of Watertown uses an organic larvicide that contains a naturally occurring spore-forming bacterium found worldwide in soil and aquatic environments that is toxic to mosquito larvae when ingested but harmless to people and animals. The City plans to apply larvicides throughout the mosquito season. This will apply not only to known breeding areas on public property, but also to all storm drains. Additional applications will occur depending on circumstances (wet weather) and monitoring.

Mosquito spraying is carried out when mosquito traps indicate significant populations of specific mosquito species that may carry West Nile virus. The public will be informed in advance when and where any adult mosquito spraying will take place. Spraying usually takes place between dusk and early morning. Announcements will be made on local radio stations and on the City of Watertown webpage (

Although most people’s risk of experiencing any health effects from mosquito spray is quite low, people who have chemical sensitivities or think the spray may make a pre-existing health condition worse (especially the elderly ) must take special measures to avoid exposure. Consult your doctor if you have any specific medical concerns about how mosquito spray may affect you.

Here are some common sense steps to follow when mosquito spraying becomes necessary in your neighborhood:

1. If possible, stay indoors whenever spraying occurs.

2. Keep children indoors while spraying and for approximately one hour after spraying.

3. Close windows and doors and turn off your air conditioning (or set it to circulate indoor air) before you start spraying.

4. If you must stay outdoors, avoid eye contact with the spray. If you get mosquito spray in your eyes, flush them immediately with water.

5. Wash exposed skin surfaces with soap and water if you come in contact with the mosquito spray.

6. Rinse home-grown fruits and vegetables thoroughly with water before cooking or eating.

7. Cover outdoor tables and play equipment, or wash with soap and water after spraying.

8. Bring laundry and toys inside before you start spraying. Wash with soap and water if exposed to mosquito spray.

9. Bring pets indoors and cover ornamental fish ponds to avoid direct exposure.

10. Consult your doctor if you think the spray is affecting your health. To reduce exposure to mosquitoes and the risk of becoming infected with West Nile virus, the following steps are also recommended:

1. Stay indoors at dawn, dusk and early evening.

2. Wear light-colored, long-sleeved shirts and long pants made of tightly woven materials whenever you are outdoors.

3. Spray clothing with mosquito repellents containing picaridin, IR3535, oil of lemon eucalyptus (OLE) or para-menthane-diol (PMD), 2-undecanone or DEET, as mosquitoes can bite through thin clothing. An effective DEET repellent will contain 35% DEET (N,N-diethylmeta-toluamide). DEET in high concentrations (above 35%) offers no additional protection. For children, use repellents containing no more than 10% DEET.

4. Apply insect repellent sparingly to exposed skin.

5. Mosquito repellents can irritate the eyes and mouth, so avoid applying repellent to children’s hands.

6. Whenever using mosquito spray or insect repellent, be sure to read and follow the manufacturer’s DIRECTIONS FOR USE, as printed on the product.

7. Note: Vitamin B and “ultrasound” devices are NOT effective in preventing

mosquito bites.

8. Turn off all lights that may attract mosquitoes. Use yellow “bug lights” to

exterior light. Yellow lights are less attractive to insects.

9. Keep grass and weeds cut short to reduce mosquito hiding places.

10. Window and door screens must be “watertight”.

As mentioned earlier, the efforts of the city’s mosquito control program are focused on reducing the local mosquito population by identifying, monitoring and treating areas within the city limits that have been determined to be the major local breeding grounds for mosquito species that are more likely to carry West Nile Virus. All of these areas are located on city-owned land.

Individual homeowners can do a lot to control mosquitoes on their private property. If everyone took a few minutes each week to check the following potential mosquito breeding areas around their homes, the mosquito population in your neighborhood would be significantly reduced:

  • Cans and buckets. Throw them away, store them indoors or turn them inside out.
  • Old tires. Store them in the basement or in a shed where they won’t collect rainwater.
  • Barrels and trash cans. Drain and store well covered or upside down.
  • Roof gutters. Clean up leaves and debris that trap and hold water. Repair sagging gutters.
  • Bird baths. Change and clean the water daily.
  • Paddling pools. Change the water every few days, but make sure the water you throw away drains. Turn inside out when not in use.
  • Canoes and boats. Cover with a tight fitting tarp or turn over. Open the drain plug and tilt the boat so the water drains out.
  • Ornamental pools. Stock with small fish that will eat developing mosquitoes.
  • Puddles and marshy areas. Level to drain water or fill with soil.
  • Flower pots and vases. Empty standing water from saucers and change the water in outdoor vases every other day.
  • Leaky faucets and pipes. Repair leaky faucets and the drain area below.
  • Tarps or plastic sheets. Make sure boat liners, swimming pools, compost heaps, etc. are tight and sloped so that rainwater runs off.
  • Waterers for pets or livestock. Empty frequently, clean and refill.
  • Wheelbarrows. Store under cover in a basement or shed or upside down.
  • Drainage basins. Remove standing water from sumps, dry wells or drainage basins.
  • Sumps and septic tanks. Make sure systems are well covered, working properly, and not overflowing.
  • Storm sewers. Check that the water is flowing freely and is not blocked by leaves and debris.
  • Tree holes. Remove stumps or fill stumps or tree holes with sand or other filler material.

For more information on mosquitoes or West Nile virus, see the following

web sites:

-PSA received as written from the City of Watertown

Comments are closed.