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Press Releases

City of Fort Collins to Spray for Mosquitoes August 30 and September 4

This press release was posted 1,852 days ago and may contain inaccurate information.
Contact Information
  • Mike Calhoon, City of Fort Collins, West Nile Virus Program Manager, (970) 416-2079
  • Kim Newcomer, Communications & Public Involvement Manager, (970) 221-6207
  • Jane Viste, Public Information Office, Larimer County Department of Health & Enviornment, 498-6750.
image for press release City of Fort Collins to Spray for Mosquitoes August 30 and September 4 In accordance with the City’s West Nile Virus Management policy, the City of Fort Collins will spray for adult mosquitoes on August 30 and September 4 in five areas of the city. Spraying will occur primarily in the eastern side of town, as well as a section in northwest Fort Collins and a small area in Larimer County. A map of spray zones is attached or click here:
View a list of frequently asked questions here:
Weather permitting, truck-based fogging will occur between dusk and 1 a.m. on Thursday, August 30 and again on Tuesday, September 4.

The decision to spray for mosquitos follows the recommendation by Dr. Adrienne LeBailly, Director of the Larimer County Department of Health and Environment, and a majority recommendation from the City of Fort Collins West Nile Advisory panel. According to Dr. LeBailly, “the infection rate is growing, and I am concerned about the risk this presents, particularly over the holiday weekend. Based on the data, I am recommending spraying in targeted areas which present the greatest risk.”

The City’s contractor, Colorado Mosquito Control, plans to use a permethrin-based product to be applied in a fine mist which delivers 9/1000 (0.009) of a drop per square foot. To minimize pesticide exposure, residents should stay indoors and keep doors and windows closed for 30–60 minutes after spraying occurs.

The intent of spraying on Thursday is to lessen the risk of West Nile virus prior to the long holiday weekend when many residents plan to spend time outside. The second spraying, which increases the efficacy of mosquito control, will take place on Tuesday, Sept. 4, weather permitting. Following the second application, no further spraying will occur this season.

The City of Fort Collins’ West Nile Virus Management Policy aims to reduce the risk of human West Nile virus infection while limiting adverse human health and environmental impacts. The Policy prescribes a data-driven approach to determining when spraying for adult mosquitos should occur. In 2008, a Technical Advisory Committee comprised of community members and professional experts with diverse perspectives developed Program Response Guidelines that establish thresholds for action. The West Nile Management Policy and Program Response Guidelines are attached for your information.

Any recommendation for spraying originates from the Larimer County Department of Health and Environment (LCDHE) and is preceded by a detailed analysis of West Nile virus risk by a three-person West Nile Advisory panel who provide feedback to the City Manager. Per the adopted West Nile Virus Management Police, the City Manager ultimately authorizes spraying.

Residents who are listed in the White Pages will receive a phone call tonight (Wednesday, August 29) notifying them of nearby mosquito spraying activity. The City offers an automatic notification system that allows citizens to receive courtesy notices via e-mail any time their neighborhood is going to be sprayed for adult mosquitoes. Residents who are currently registered will be notified. To be registered for future notices, go to the City’s website at Fort Collins residents without internet access can sign up to receive phone notifications by calling Colorado Mosquito Control at 970-663-5697 or 970-962-2583.

In addition to City-managed adult mosquito spraying, some homeowner’s associations may be hiring private contractors to conduct additional spraying in their neighborhoods. The City of Fort Collins will not provide courtesy notifications for HOA-managed spray programs.

Residents who are registered with the Colorado Department of Agriculture Pesticide Sensitivity Registry will be contacted by Colorado Mosquito Control to discuss shut-off protocol.