CITY OF DES MOINES’
MOSQUITO CONTROL PROGRAM
For several years, the City of Des Moines has operated a mosquito control program, on a seasonal basis, in an effort to reduce the threat to public health and annoyance from mosquitoes. In addition to ordinance enforcement activities directed at breeding site reduction, and an encephalitis monitoring project operated in conjunction with Iowa State University, our program consists of two primary components: the visual inspection and treatment of standing water areas within the city that have the potential to breed mosquitoes, and a spraying program designed to reduce the numbers of adult mosquitoes in residential neighborhoods.
The following information has been compiled in an effort to provide a general description of our adult mosquito control program.
The product that we are currently using for adult mosquito control is
called Biomist. The active ingredient in this material is Permethrin. It
is a pyrethroid insecticide. Pyrethroids are synthetic versions of a natural
insecticide produced by chrysanthemum flowers. Biomist is registered with
the United States EPA for control of adult mosquitoes in urban and residential
areas. Products containing pyrethroids are widely available for home use
on houseplants and in gardens.
The material is applied according to label specifications. We are currently applying at a rate of approximately 0.00175 lbs of active ingredient per acre.
Biomist is a "contact" insecticide, only those mosquitoes that come in direct contact with the mist will be killed. There is no residual control associated with this product since it dissipates from the environment within hours of application.
Application is via two Ultra Low Volume (ULV) cold aerosol foggers mounted on pickup trucks. Our driver/applicators are certified and licensed with the State of Iowa Department of Agriculture.
Depending on seasonal weather conditions, we will typically begin spraying in late May or early June. We generally spray Sunday through Thursday nights during the late evening (after 9:00 p.m.) and early morning hours when weather conditions are favorable, pedestrian traffic is at a minimum, and mosquitoes are most active. Friday and Saturday spraying may also be authorized on an occasional, as needed basis. We spray primarily during periods when adult mosquito populations are very high, or when there is an elevated risk of mosquito borne disease transmission to the general public.
Areas of the city are sprayed on a rotating basis, generally taking 12 to 14 days to complete one cycle. Spraying is halted during times of high winds, heavy rainfall, or temperature extremes that would render the treatment ineffective. During periods of the summer when mosquito populations are low, spraying will usually be reduced or discontinued until conditions once again warrant resumption.
Since Biomist is applied at very low concentrations, most people would not be expected to experience any adverse effects from exposure to the spray. Nevertheless, Biomist is a pesticide. Certain individuals may object to or be particularly sensitive to even the very low levels of material that we apply. For this reason, the City of Des Moines offers a “shut off” option for those citizens who do not wish to be exposed to the spray.
If you wish to be added to the “shut off” list, please call 248-6099 during regular business hours with your name and address. (This number should also be used if you wish to request that your neighborhood be sprayed at the next opportunity due to high numbers of mosquitoes.)
People on the "shut off" list are contacted each year by mail, prior to the spraying season, and asked to respond as to whether or not they wish to remain on this list. In most cases, we do not travel the street in front of a “shut off” at all. However, for logistical reasons, it may be necessary for the truck to pass by a home on the list. In these rare instances, though the engine on the sprayer will continue to run, the spray is turned off from the cab at least one half block in either direction from the address of the request.
If there is a conflict between those residents requesting the spray, and those wishing not to be sprayed, we honor the shut off request.
Additionally, once again this season, a mosquito "Hot Line" will be available to the general public. A telephone message will relay information regarding areas of town where our trucks are scheduled to spray on a particular evening. The message will be updated on a daily basis, or as needed throughout the season. Individuals can utilize this information to plan outdoor activities, or make arrangements to reduce their exposure to the spray if they choose to do so. The "Hot Line" number is 248-6099.
For additional information regarding the City’s mosquito control program, product information, or current anticipated spray schedule, feel free to phone 237-1612 between the hours of 8:00 a.m. and 4:30 p.m. Monday through Friday.