Aquatic herbicide application for Curly-leaf pondweed control will be carried out the week of September 13 or the week of September 20, 2021 in the areas outlined below.
The Curly-leaf pondweed treatment occurred today, Tuesday, September 21, 2021.
Water use restrictions are no longer in effect for irrigation intakes. No further updates will be provided.
Please refer to treatment maps and water use restrictions below for additional information about these treatments.
NOTICE OF 2021 LAKE COEUR D'ALENE
CURLY-LEAF PONDWEED TREATMENT
Dear property owners and lake users,
Curly-leaf pondweed has been identified as a significant invasive species within Lake Coeur d'Alene, Idaho and is known to negatively affect the beneficial uses of a waterbody. As such, an aquatic herbicide treatment is planned for portions of northern Lake Coeur d'Alene between the week of September 13 and the week of September 20, 2021, based on lake level, water temperature, plant growth and weather permitting. The treatment timing was selected to maximize treatment efficacy when Curly-leaf pondweed is actively growing. Up to 9 acres of the lake will be treated during one treatment event with liquid endothall (Aquathol K, EPA Registration # 70506-176) and liquid diquat (Reward, USEPA Registration # 1091A-L2G 1009 and/or Littora, USEPA Registration # 67690-53). Please see the following website for additional information about diquat and endothall herbicides.
Water use restrictions will be in effect due to the presence of irrigation water intakes within the treatment areas. The following water use restrictions apply:
Irrigation:Irrigation restrictions will be in effect for irrigation to turf and ornamentals during and 3 days after treatment or until post treatment analysis confirms diquat level is below 0.02 ppm.
Recreational Use of Water in treatment Area: There are no swimming or fishing restrictions within the treatment areas.
Human Consumption: Potable water restriction in effect during and after treatment within the treated area for 3 days or until post treatment analysis confirms diquat level is below 0.02 ppm. However, there are no known potable drinking intakes that exist within or adjacent to the treatment area.
Animal Consumption:Livestock and domestic animal water use restriction in effect during and after treatment within the treated area for 1 day or until post treatment analysis confirms diquat level is below 0.02 ppm. However, there are no known potable drinking intakes that exist within or adjacent to the treatment area. This restriction does not apply to indidental exposure.
For up to date information on water use restrictions please and treatment date visit the applicator’s website.
Please contact Tom Moorhouse, Aquatic Pest Control Adviser with Clean Lakes, Inc., (208-929-2757) or Rob Stephens, Restoration Biologist, Avista (509-495-4340), with any questions.
For information related to the aquatic herbicides that will be used, Aquathol K and Reward/Littora, please go to the following link where the herbicide label and Material Safety Data Sheets are available for review: