Fragrant water-lily floats on top of Lake Ballinger and Eurasian milfoil is seen beneath the surface. Both are classified as invasive plants that affect the lake’s water quality. (City of Mountlake Terrace)

Fragrant water-lily floats on top of Lake Ballinger and Eurasian milfoil is seen beneath the surface. Both are classified as invasive plants that affect the lake’s water quality. (City of Mountlake Terrace)

Herbicides might be used to kill milfoil in Lake Ballinger

A public workshop about environmental concerns is scheduled for May 29 in Mountlake Terrace.

MOUNTLAKE TERRACE — It’s a green invasion that is pesky and stifling.

Folks living along the south shore of Lake Ballinger began noticing Eurasian milfoil in the fall of 2015. Two years later, the intruder had spread dramatically, creating dense weedy mats that cover much of the shore.

Now, the city of Mountlake Terrace and other jurisdictions are hoping to bring the Eurasian milfoil and two other non-native noxious weeds under control. The approach, which has involved seeking permits from the state Department of Ecology, could use a combination of herbicides as well as volunteer efforts to manually remove the weeds over several years.

A 2018 study found the Eurasian milfoil covering 16.8 acres of the lake; the fragrant water lily pads, 13.3 acres; and the curly leaf pondweed a little over half an acre. The lake itself covers about 103 acres. Inside the lake is 3-acre Edmount Island.

“With an infestation of that severity, options needed to be developed,” said Laura Reed, stormwater program manager for the city of Mountlake Terrace.

The invading plants are hurting native ones.

“The overly dense aquatic plant growth also greatly impairs habitat for fish and other aquatic species and negatively impacts water quality by increasing nutrient recycling and oxygen demand,” an environmental consulting firm wrote in its study of Lake Ballinger.

In 2018, Tetra Tech identified three non-native, noxious weed species in the lake. The Eurasian milfoil is designated as a Class B noxious weed by Snohomish County. That designation requires it be controlled.

The city was asked by local residents to look into the problem. It has worked closely with the Department of Ecology. Early on, the agency provided a $25,000 grant to map the aquatic plants in the lake and write a management plan.

Lake Ballinger is by no means alone.

“The Eurasian milfoil is an issue in a lot of our lakes,” said Colleen Keltz, a Department of Ecology spokesperson for water quality issues. “It’s all over Western Washington.”

A steering committee was formed to help Lake Ballinger. It included people from Edmonds and Mountlake Terrace, a representative from the nearby Nile Shrine Golf Course, and staff from both cities. The panel worked closely with Tetra Tech to come up with options.

The proposal is a combination of herbicides as well as volunteer efforts, such as cutting and raking as well as placing sand-filled burlap bags on the lake bottom.

The recommended herbicides are Fluridone and Florpyrauxifen-benzyl in low-dose applications over parts of the lake over several years. The Florpyrauxifen-benzyl would be used on 9 acres of milfoil in July or August; Fluridone would be used on fragrant water lilies and curly leaf pondweeds in August or September. The annual cost would be around $17,000, which would treat about half of the milfoil and a quarter of the fragrant water lilies and curly leaf pondweed in infested areas each year.

Reed said the herbicides were chosen because they are considered the least risk to humans and wildlife and would cause the fewest restrictions for fishing and swimming.

A survey of Hall Lake, upstream from Lake Ballinger, found variable leaf milfoil, an invasive considered a Class A noxious weed in Washington state. That designation requires it to be eradicated.

A public meeting to answer questions about the Lake Ballinger environmental issues is set for 7 to 8:30 p.m. May 29 at Mountlake Terrace Community Senior Center, 23000 Lakeview Drive.

Comments can be made to or 425-744-6226.

Eric Stevick: 425-339-3446;

Talk to us

More in Local News

A Sound Transit train arrives at Westlake Station in downtown Seattle. (Sue Misao / Herald file) May 2019
Should light rail skip Paine Field and Boeing? We asked, you answered

More than 300 Herald readers responded to an online poll. Here are the results.

Logo for news use featuring the municipality of Lake Stevens in Snohomish County, Washington. 220118
Highway 9 work could disrupt travel through Lake Stevens

Construction is set for roundabouts on South Lake Stevens Road and one at North Davies Road and Vernon Road.

Lynnwood City Council members, from left: Jim Smith, Shirley Sutton, Shannon Sessions, Josh Binda, George Hurst, Julieta Altamirano-Crosby, and Patrick Decker. (City of Lynnwood)
No penalty for Lynnwood council member’s ‘underinformed’ views on racism

The City Council didn’t censure Jim Smith after a report found he discriminated against a Black city employee.

All ears: Mukilteo couple provides surgery for kids born without ears

Dr. Prabhat and Trish Bhama are part of a HUGS volunteer team providing treatment for microtia in Guatemala.

Conceptual rendering for a future section of Smokey Point Boulevard between 174th Place NE and 200th Street NE. (City of Arlington)
Plan seeks to transform Smokey Point Blvd. into ‘neighborhood corridor’

City officials hope roundabouts, sidewalks and more will turn 2 miles of busy road into a neighborhood street.

Genghin Carroll, 8, walks up and high fives his mom Andria Carroll after riding the ferry over to meet her for a dental appointment on Thursday, Sept. 29, 2022 in Mukilteo, Washington. (Olivia Vanni / The Herald)
Welcome aboard, kids! Ferry rides are free for those 18 and under

The move to let children ride ferries for free is the latest result of Move Ahead Washington legislation.

Judge Paul Thompson, left, with Strom Peterson and his wife Maria Montalvo after being is sworn in Wednesday afternoon at the Snohomish County Administration Building in Everett, Washington on September 29, 2022.  (Kevin Clark / The Herald)
State Rep. Peterson appointed to Snohomish County Council

Carin Chase had by far the most supporters present Thursday, but it was Strom Peterson who won the council’s unanimous vote.

Students make their way after school at Edmonds-Woodway High School on March 12, 2020. All public and private schools in Snohomish, King and Pierce counties must close for six weeks. (Kevin Clark / The Herald)
Police: Student, 15, arrested with loaded gun at Edmonds high school

Around 1 p.m., students reported a classmate with a gun at Edmonds-Woodway High School.

A woman was injured in an attack Sunday at Clark Park in Everett. (Everett Police Department)
Police: Purse snatching in Everett park led to stabbing

A Snohomish woman, 36, was arrested for investigation of first-degree assault and first-degree robbery.

Most Read