Mosquito Control

Denver’s Mosquito Management Program uses an approach designed to reduce mosquito breeding sites and larval mosquito survival and provide information and education to residents and business to help them keep mosquito populations at a safe level.

We recognize mosquitoes are a nuisance and can be especially active in neighborhoods that are near waterways and natural areas. The program focuses on preventing mosquitoes through these activities:

Minimize standing water where possible.
Survey larval mosquito populations in around 70 sites city-wide, and apply larvicide (kill mosquito larvae) when conditions warrant it.
Trap, count, and test adult mosquitoes to monitor for West Nile Virus.
Investigate and respond to citizen concerns.
Partner with neighborhood organizations and other land owners to assist them in controlling mosquitoes. Our partners include:
- Bluff Lake Nature Center
- Central Park
- Denver Water
- Green Valley Ranch Metropolitan District
- Lowry Community Master Association
- Sand Creek Regional Greenway
- Small and large private business and facility owners

Protect yourself from mosquitoes

You can protect yourself and your neighbors from mosquito bites in two ways – elimination of stagnant water where mosquitos breed and prevention.

Eliminate Mosquito Breeding Sites

Frequently remove standing water from containers, tires, birdbaths, gutters and buckets around your home
Do not overwater your yard, as it can create standing water in gutters, storm sewers, and within your turf and other landscaping
Properly maintain fountains and swimming pools to ensure circulation, or drain and cover if not in use- if these are not viable options, apply larvicide as needed to prevent adult mosquito emergence

Prevention Tips

Limit activity outdoors at dusk and dawn
Wear protective clothing like pants and long sleeves when outdoors
Wear mosquito repellant containing lemon eucalyptus oil, DEET, picaridian, or IR3535
For more information on insect repellants, visit EPA’s website.

Mosquito-Proof Your Home

Install screens on windows and doors
Make sure roof gutters are not clogged and holding water
Incorporate xeriscape (non-watered landscaping) to further help reduce the number of mosquitoes in your neighborhood

Education

Understanding mosquitoes is the first step in preventing them. We offer a variety of educational materials and information focused on neighborhood-level prevention of mosquitoes. Please call 3-1-1 or email EQcomments@denvergov.org for additional information.

Preventing mosquito habitats and breeding grounds

Dump containers holding water (wheelbarrows, buckets); weekly
Maintain fountains and swimming pools, drain water or assure it is moving and/or being chlorinated (or equivalent);
Assure you don’t have blocked roof gutters holding water and producing mosquito habitat;
Do not allow landscape irrigation to collect and pool in sidewalks, gutters, and within your turf and other landscaping;
Make wise landscape decisions (create spaces that make it easier to avoid overspray into gutters and sidewalks);
Fix leaking irrigation systems; and
If you do have pooling in street gutters, disturb it regularly (with brooms, vehicles, etc).

West Nile Virus and Zika Virus

West Nile Virus

Denver traps and collects adult mosquitoes at five sites across the city to determine if West Nile Virus (WNV) is present in local mosquito populations. The samples are sent for testing to the Colorado Department of Public Health and Environment. These results are used to calculate an index which is used to estimate the level of risk.

Since 2007, adult mosquitoes testing established that WNV will most likely be prevalent within Denver’s adult mosquito populations. It will also be found within the mosquito populations up and down the front range.

What does this mean for you?

While the risk of exposure to WNV is typically low, you should still protect yourself. Mosquitoes remain active within our region through September or until colder nights set in (e.g. 40’s). Anecdotally, while the number of adult mosquitoes generally declines in the latter end of the summer, the percentage of those mosquitoes carrying WNV seems to increase. People should continue using precautions through September.

See “Protect Yourself from Mosquito Bites” for more information.

Zika Virus

Zika Virus is most commonly spread to people through mosquito bites. The mosquito that spreads Zika lives mostly in warm (tropical and subtropical) regions of the world and is not found in Colorado. The risk of Zika coming to Colorado and spreading through mosquito bites is very low.

DDPHE and the Public Health Institute at Denver Health are working closely to monitor the spread of the disease, identify risks and plan for the possibility of a case in the metro area.

Learn more about Zika Virus.