The Newman Lake Flood Control Zone District, under permit from the Washington Department of Ecology, has hired Aqua Technex to treat milfoil infestations on about 25 acres throughout the 1,200-acre lake with 2-4-D (dichlorophenoxyacetic acid, dimethylamine salt).
A swimming restriction will be in force during treatment and for 24 hours after treatment. Signs will be posted discouraging swimming and boating the day of treatment and for two days afterward. The boating restriction is needed because wave action reduces the herbicide's effectiveness.
Karen Kruger, Spokane County water resources technician, said aquatic weed treatments at Newman Lake during the past two summers have reduced the original infestation tremendously, thanks in part to volunteer efforts to help keep boaters out of the herbicide application areas.
Aquatic herbicide application permits authorized by Ecology include requirements and restrictions to protect fish and wildlife.
WDFW access manager Scott Young said the gates to the area will be closed early on Tuesday, June 2, and re-opened early on Friday, June 5.
Newman Lake is about 20 miles northeast of Spokane, about two miles west of the Idaho border, and is open year-round for fishing.