Aquatic herbicide application is scheduled to be carried out in specific management areas of Hayden Lake for the control of Eurasian watermilfoil between
August 25-27, 2026, based on water and weather conditions.
Applications were carried out August 25, 2026.
No further treatment will take place
See below for information to access the ISDA management area map.
There are no restrictions for potable water use, swimming or fishing.
There are no restrictions for irrigation of turf.
There are no food crop and non-food crop irrigation water use restrictions in effect.
No additional updates will be provided.
Please see below for additional information.
NOTICE OF 2026 HAYDEN LAKE, IDAHO
EURASIAN WATERMILFOIL TREATMENT
Dear property owners and lake users,
Eurasian watermilfoil has been identified as a significant invasive species within Hayden Lake, Idaho and is known to negatively affect the beneficial use of a waterbody. As such, an aquatic herbicide treatment is planned for specific areas of Hayden Lake between August 25-27, 2026 based on water and weather conditions. The treatment timing was selected to maximize treatment efficacy when Eurasian watermilfoil is actively growing. Specific areas of the lake will be treated with liquid florpyrauxifen-benzyl (ProcellaCOR EC, USEPA Registration # 67690-80). This notice is being posted to Eurasian watermilfoil management areas and within 1/4 mile of management areas.
Water use restrictions will be in effect for irrigation water intakes within the treated areas of the lake. The following water use restrictions will apply:
Irrigation Use of Water: Do not irrigate established food crops until water use restrictions are lifted. Do not irrigate other non-food crops, such as landscape ornamentals, until water use restrictions are lifted. There is no restriction for irrigation of turf.
Recreational Use of Water in Treatment Areas: There are no swimming or fishing restrictions within the treatment areas.
Potable Water in Treatment Area: There are no restrictions on consumption of treated water for potable use or by pets or other animals.
For up to date information on water use restrictions during and after treatment, treatment date and treatment location, please visit the Idaho State Department of Agriculture's and the applicator's websites:
Please contact Tom Moorhouse, Aquatic Pest Control Adviser with Clean Lakes, Inc., (208-929-2757) or Noxious Weeds, Idaho State Department of Agriculture (208-332-8667), with any questions.
For information related to the aquatic herbicide ProcellaCOR® that will be used, please go to the following link where the herbicide label and Safety Data Sheet are available for review:
Location information for management areas is available at the Idaho State Department of Agriculture website that provides an interactive map at the following link.
