Mosquito Control Program

Morrow BioScience Ltd.  July 2022 Mid-Season Updates

On July 27, 2022, Morrow BioScience Ltd. (MBL) released their 2022 Mid-Season Update Report for the RDCK Mosquito Control Program. The goal of the Mid-Season Update Report is to provide a summary of the treatments and other activities undertaken during the 2022 mosquito season in additon to characterizing the environmental conditions and climate influences. 

Report summary:  Environmental Conditions and subsequent treatments

  • The 2022 snowpack was 101 and 115 percent of normal, respectively, immediately prior to the mosquito season.
  • In response to the relatively warmer weather in June and record-high snowpack input, the Duncan River peak occurred on 6 June (3.265 m) and the Kootenay Lake peak occurred on 15 June (533.885 m).
  • The Duncan Dam peaks were the highest recorded since 2018 and, thus, triggered a compounded number of dormant floodwater mosquito eggs to hatch causing high larval abundance.
  • May and June precipitation accumulation were considerably higher-than-average and likely contributed to already high Duncan River levels, as well as ephemeral mosquito development sites.
  • Site monitoring began in mid-April and treatments commenced in June within the program purview.
  • High river and lake levels resulted in a need for two aerial treatment campaigns in Meadow Creek.
  • Ground treatments were highest in June, with the peaks of the Duncan River and Kootenay Lake.
  • A bacterial larvicide, AquabacÒ (active ingredient - Bacillus thuringiensis var israelensis) was used to treat approximately 760 ha required for floodwater and snowmelt mosquito control within the Meadow Creek and Pine Ridge area, as of 24 July. Post treatment monitoring revealed moderate efficacy rates throughout targeted sites. Higher treatment rates should be used in future seasons.
  • A town hall meeting was facilitated by the RDCK program manager on 4 May. MBL staff attended virtually and provided a summary of the 2021 season and a projection for the 2022 season

To report standing water or adult mosquito nuisance, please email the Mosquito Hotline: or call the numbers listed below.

Visit MBL's website to learn more about mosquitoes, read Frequently Asked Questions and access their blog.

2021 Pest Management Program Application Information for Pest Management Plan Number RDCK-PMP-2021/2026

The RDCK is renewing a Pest Management Plan and will submit the plan for approval under the Integrated Pest Management Act. This Plan will describe a Mosquito Control Program using Integrated Pest Management, including the use of insecticides.

Purpose:  Mosquito Control for the purpose of nuisance control.
Application Method: Treatment of mosquito larval development sites by hand and aerial application.
Location:  The areas to be included in this Pest Management Plan (PMP) application are limited to public and private lands within the following existing program areas:

  • The floodplain area below the Duncan Dam between the south end of Duncan Lake and the north end of Kootenay Lake. Within this floodplain are the following communities:  Duncan Dam, Meadow Creek and Cooper Creek.
  • Within the boundary of the RDCK Bylaw 1642 for the Pineridge subdivision area.

Pesticide:  Yearly totals up to, but not exceeding:

  • 1,000 ha with Aquabac (PCP No. 26863) (Bacillus thuringiensis var israeliensis)
  • 1,000 ha with Aquabac XT (PCP No. 26860) (Bacillus thuringiensis var israeliensis)
  • 1,000 ha with Aquabac 200 G (PCP No. 19466) (Bacillus thuringiensis var israeliensis)

A selection of insecticides has been chosen to increase the ability to target mosquito populations in the most environmentally responsible method possible. All products listed are registered in Canada for the intended use. Bacillus thuringiensis var israeliensis has been chosen to control larval mosquitoes in their development sites.  These pesticides are target specific, non-residual, and non-toxic.

The RDCK will not treat the total area of all the products listed above but will choose the best method to treat with the least environmental impact.  All products are registered for mosquito control in Canada.

This project will begin April 30, 2021 and be completed by April 30, 2026.

A person wishing to contribute information about a proposed treatment site, relevant to the development of the pest management plan, may send copies of the information to the applicant at the address below.

Any member of the public wishing to view the application or associated material can do so online or by requesting a digital copy at the contact number below (arrangements can be made if digital access is not possible). If clarification is required regarding this application, please contact the applicant:

Regional District of Central Kootenay
PO Box 590, 202 Lakeside Drive
Nelson, BC   V1L 5R4
Attention:  Todd Johnston
PH:  (250) 352-1523

Report Mosquito Problems - Pineridge and Duncan Dam Areas

Residents covered under the Pineridge Subdivision Area Mosquito Control Service Establishment Bylaw No. 1642 and Portion of Electoral Area D Mosquito Control Extended Service Area Establishment Bylaw No. 1293 can report serious concerns regarding the mosquito program.

During Regular Business Hours:         250-352-1523 / 1-800-268-7325 (Ext. 1523)
(8:30 am - 4:30 pm, Mon - Fri)
After Regular Business Hours:            250-352-1525 / 1-844-313-1913

Residents are encouraged to call during regular business hours for issues that are not time sensitive.  NOTE:  The after hours toll-free number is not always responded to immediately.  Leave a message and we will endeavor to respond the same day.

Since 2001 the RDCK has coordinated a mosquito control program in a portion of Electoral Area D (Duncan Dam) Service Area and the Pineridge Subdivision Service Area.  Detailed information on the Mosquito Control Program.  Here are some simple actions you can take right in your own backyard to help reduce local mosquito populations and make summer a little more comfortable.

The 2021 Final Report prepared by Morrow BioScience summarizes the 2021 mosquito control season. 

The Pre-season Report prepared by Morrow BioScience  provides predictions for the 2022 mosquito season based on current environmental conditions and anticipated climate influences.

The goal of the Program is to minimize the nuisance mosquito population to a tolerable level in the Area D-Duncan Dam and Pineridge Sudivision service areas.  Contracted nuisance control activitied are undertaken in an effort to avoid negative impacts to the local economy and quality of life of our residents which can result from a high nuisance mosquito population.  The RDCK's program is primarliy focused on larval mosquito control through ground and aerial application of biological larvacides, but may also involve additional work related to West Nile Virus surveillance and control.

The content on this page was last updated September 28 2022 at 4:35 PM