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The following are some of the most frequently asked questions we receive at Benton County MCD. If you have a question that is not answered in this section, e-mail us, and we will be happy to further assist you.

Q: What can I do to prevent mosquitoes around the house?

A: The number one thing you can do to prevent mosquitoes is to not give them a place to lay their eggs and develop. Mosquitoes will generally take about 7 days (it can be as little as 4) to complete the life cycle of egg to adult and they need water for this to happen. So if homeowners make sure they change out or discard any standing water at least once a week then the mosquitoes will not have a chance to develop.

Q: Q: What are the boundaries of Benton County Mosquito Control District?

A: The District consists of 7 municipalities and limited surrounding county lands: Kennewick (including Finley), Richland, West Richland, Benton City, Prosser, parts of Grandview and Mabton. The District is located mainly within Township 9 (but goes into Townships 8 & 10) and runs east to west from a portion of Range 31 to the edge of Range 23. If you are unsure as to whether or not you are in the District, just give us a call and we will be happy to find out for you.  Or you can use the District Map link to check for yourself if you are within the boundaries.

Q: Q: What can I do to reduce my risk of becoming infected with West Nile virus?

A: Here are preventative measures that you may choose to take:

  • Avoiding areas with mosquitoes is your best defense but it is not always practical or possible. In situations where you anticipate mosquitoes being present, using an insect repellent can be an effective protective step. The Centers for Disease Control recommend using a product with DEET, picaridin or IR3535. If you prefer a natural product, you can use Oil of Lemon Eucalyptus, but please note that its protection is similar to products that contain a low percentage of DEET.
  • Apply insect repellent sparingly to exposed skin. The more DEET a repellent contains the longer time it can protect you from mosquito bites. A higher percentage of DEET in a repellent does not mean that your protection is better, just that it will last longer. DEET concentrations higher than 50% do not increase the length of protection. Choose a repellent that provides protection for the amount of time that you will be outdoors. Examples; a product with 20% DEET will give about 4 hours of protection and a product containing 6.65% DEET will give almost 2 hours protection.
  • Repellents may irritate the eyes and mouth, so avoid applying repellent to the hands of children.
  • Whenever you use an insecticide or insect repellent, be sure to read and follow the manufacturer's DIRECTIONS FOR USE, as printed on the product.
  • Spray clothing with repellents containing permethrin, DEET, picaridin, IR3535 or oil of lemon eucalyptus since mosquitoes may bite through thin clothing. Do not apply repellents containing permethrin directly to exposed skin. If you spray your clothing, there is no need to spray repellents on the skin under your clothing.
  • Try wearing loose fitting clothing to give you a cushion or depth to protect from bites.
  • When possible, wear long-sleeved shirts and long pants when outdoors.
  • Place mosquito netting over infant carriers when outdoors.
  • Consider staying indoors at dawn, dusk and in the early evening, which are peak mosquito biting times (for most species).
  • Install or repair window and door screens so that mosquitoes cannot get indoors.
  • To avoid helping mosquitoes breed in your environment; drain standing water. Routinely empty water from flower pots, pet bowls, clogged rain gutters, swimming pool covers, discarded tires, buckets, barrels, cans and other items that collect water in which mosquitoes can lay eggs.
  • Benton County MCD believes that a repellent is your best line of personal defense, but using a repellent is a personal deciion. Repellents are recommended by the Centers for Disease Control, Washington State Department of Health, and Benton County MCD as an effective means for personal protection. This still needs to be an individual decision; if you choose to use a repellant, please follow all label instructions.
  • More information about West Nile Virus may be found at:

Q: What do I do if I have a water site that I think is breeding mosquitoes?

A: If you remove the mosquito habitat then you won't have mosquitoes coming from that source. If you dump out or exchange water once a week then there will not be enough time for the mosquito to complete its metamorphosis and become an adult.

If you can't change out the water; give your local Mosquito Control District a call and they will come out and survey the site to see if it needs to be treated for mosquitoes. If necessary, they will have products available to kill the mosquitoes that are present or will suggest other options to control the potential problem.

Q: What do I do if I find a dead bird?

A: There is not presently, any organization that is collecting dead birds. Click here to find information and instructions related to dead bird handling and reporting.

Q: What are Gambusia or mosquitofish?

A: Mosquitofish are used, in selective applications, to reduce the number of offspring in mosquito breeding areas. Click here for more information about Gambusia and their roll in mosquito control.

Q: How do I get mosquitofish?

A: Mosquitofish may be requested for delivery and application for certain private water sources such as ponds or troughs. Click here for more information about requesting mosquitofish for your property.

Q: What is Benton County Mosquito Control doing to survey for possible diseases in the area?

BCMC conducts mosquito monitoring to try and locate the presence of a mosquito-borne illness before it shows up in humans, horses, pets or livestock.

Mosquito Monitoring is the process of collecting adult mosquitoes to be identified, separated and tested. BCMC uses CO2 traps to attract and collect adult female mosquitoes. The trap is made up of a cooler that holds dry ice (with holes in the bottom), a fan and a catch bag. Dry ice emits carbon dioxide as it sublimates (goes from solid to gas) and this is a strong, long-range attractant to female mosquitoes (only females bite). When the female gets close to the trap the fan sucks the mosquito into the catch bag, which is then collected the following morning. The mosquitoes are then separated by species and samples are either tested in-house or sent to a state accredited lab.