Herbicide treatment planned for Lake Wilderness
July 13, 2010 · 5:05 PM
Lake Wilderness will be treated with the aquatic herbicide Aquathol (active ingredient dipotassium salt of endothall) and Reward (active ingredient Diquat dibromide) within the next 10 to 21 days.
About 10 to 21 days before the treatment the herbicide applicator will mail out notices to all business and residents within one quarter mile in either direction of the shoreline or across the water from the treatment areas. No more than 48 hours before treatment, the applicator will also post signs on the public and private shoreline properties 400 feet of the treatment areas. The postings will state:
• no swimming during treatment or for 24 hours after treatment;
• no potable water withdrawals;
• no irrigation water withdrawals until concentration is less then 0.1 parts per million (usually 72 hours) and
• there are no restrictions for fishing.
The treatment is consistent with city of Maple Valley's permit coverage under the Aquatic Plant and Algae Management General Permit No. WAG-994020 issued by Washington State Department of Ecology and with the Lake Wilderness Integrated Aquatic Vegetation Management Plan (IAVMP.) The licensed herbicide applicator is Terry McNabb of Aquatechnex and questions about the application can be directed to 360-201-2612. The city has authorized the applicator to use an internal combustion engine on the boat during the herbicide application.
Treatment will be limited to the approximately five acres in the south-southwest bay, one acre in the boat launch area and one to two acres near the swimming beach.
Integrated Aquatic Vegetation Management Plan (IAVMP) [PDF]
Aquatic Plan and Algae Management General Permit [PDF]
The Integrated Aquatic Vegetation Management Plan and the Aquatic Plant and Algae Management General Permit are also available for viewing at City Hall.
For more information visit www.maplevalleywa.gov/lakes.