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West Nile Virus

 Contact Information

FAQs for Mosquito Spraying Due to Risk of West Nile Virus

Where can I find a map, and what do the numbers and colors on the map mean?

Maps of the spraying zones will be posted online when spraying is announced. The numbers and colors are the designated areas that have been identified for spraying. They are meant to help the viewer differentiate between areas quickly.

What chemical will you use?

The name of the product is Aqualuer 20–20. The active ingredient is Permethrin and it is applied at a rate of .0035 lbs. of Permethrin per acre by a truck–mounted ultralow volume spray rig. It is an EPA–approved product for mosquito control. The West Nile Virus Technical Advisory Committee researched many products for this type of control and this is the best product currently on the market for our application. Permethrin degrades in sunlight and in water, so a good practice would be to irrigate gardens the morning after application.

How does permethrin work?

Permethrin can affect insects if they eat it or touch it. Permethrin affects the nervous system in insects. Permethrin is more toxic to insects than it is to people and dogs. This is because insects can't break it down as quickly as people and dogs. Cats are more sensitive to permethrin than dogs or people.

Learn more about permethrin.

What precautions should I take to minimize exposure during mosquito spraying?

To minimize pesticide exposure, residents should stay indoors and keep doors and windows closed for 30-60 minutes after spraying occurs. Bring pets indoors as well.

Is it safe for pets? Can I let them outside?

It is recommended that family pets be brought inside during the spraying application. Please allow at least 30 minutes to pass before going outside or letting your pet outside.

How should I protect water features or ponds in my yard?

To try to reduce the exposure to pesticides, you could take the time to cover any water features in your yard. A tarp or a sheet will suffice; the chemical is applied as a mist and it will not penetrate the sheet.

What about protecting my garden?

You can minimize exposure to the pesticides by covering your garden with a tarp or sheet. The chemical does not penetrate the skin of vegetables, so if your garden was uncovered, washing vegetables with warm soap and water will remove any pesticide residue.

Can I opt out of the spraying?

No. The risk of West Nile virus is considered a public health issue. The City will only make special accommodations for those residents who are listed on the Colorado Department of Agriculture’s Pesticide Sensitive Registry. More information is available on their website.

Can I run my air conditioning?

Yes, you can run your air conditioning, but we recommend covering the fresh air intake for your system while spraying occurs.

Why didn't I get a notification?

You will not receive a notification if you don't have a land line.
You will not receive a notification if you are not listed in the white pages.
If you're not in the white pages and you have not signed up for the opt in, you will not receive a notification.
If you're having phone problems, you may not get one.
If you're not home and don't have an answering machine or you do and it is not turned on, you will not get one.
If you have a "No Solicitor" recording, you will not get a message.
If you have a message where the caller has to hit a key, such as "press 1," you will not get one. The system can't dial other numbers once you connect to the line. So if you are not home and you have this set up, you will not get one.
If you have an answering machine greeting that is too long, you may not get a message.