A presentation on possible solutions to invasive aquatic vegetation in Lake Ballinger and a review of the city’s 2019 -2024 Six-Year Transportation Improvement Program (TIP) were among the items heard by the Mountlake Terrace City Council during its Thursday, Aug. 30 work/study session.
The state requires an annual update on the TIP, and the council at its Sept. 4 business meeting will hold a public hearing on a proposed ordinance to do just that. (The meeting is a day later than normal due to Labor Day.)
Regarding Lake Ballinger, Public Works Director Eric LaFrance told the council that the city completed an aquatic plant survey in June 2018. That study, funded by the State Ecology Department, found two non-native invasive plants — Eurasian watermilfoil and fragrant water lily — that have put a damper on boating, swimming and fishing, and have also impacted habitat and water quality for fish and other aquatic species.
A steering committee was formed, consisting of concerned citizens from Edmonds and Mountlake Terrace, the greens supervisor from the nearby Nile Golf Course, and staff from both Edmonds and Mountlake Terrace. The committee met with technical experts from TetraTech and came up with a list of options for controlling the non-native plants, LaFrance said.
The recommended management strategy, he said, is to use a combination of control methods including burlap bottom barriers, cutting and raking, and herbicide applications. The recommended plan is to apply Department of Ecology-approved herbicides to 25 to 50 percent of the target area during a two- to four-year period, depending on funding availability. The estimated cost is $8,000-$15,000 per year to treat 25 percent of the lake.
However, LaFrance said that controlling the vegetation growth is a long-term proposition, that could take eight to 12 years. “There are short term grants and we are planning to apply for those,” he told the council. “But that’s not a feasible way to fund the entire effort.” One of the steering committee’s recommendations is to take a closer look at increasing assessments from Lake Ballinger’s lake management district, currently funded thorough a yearly fee paid by by lakeside homeowners, to cover the cost of herbicide treatment. Increasing the fee would require a 60 percent positive vote from affected homeowners, LaFrance said.
Councilmember Laura Sonmore asked about the type of herbicide being used, noting recent publicity regarding the herbicide Roundup. LaFrance replied that the herbicide being considered is Fluridone. “Its effective dose is micrograms a liter. It applies every two weeks between May and June during the growing season.” Fluridone blocks the production of ccausing plants to die because they can’t photosynthesize, he said.
“At the concentrations that we are proposing, it’s actually below the level that the government allows you to drink,” LaFrance said, adding that it is not a danger to human or animal health in those concentrations.
“This is a very gentle herbicide,” he said.
The steering committee has identified some priorities for vegetation control, LaFrance said, the first being spot control in the public areas — the boat launch and Ballinger Park. Another priority is to address another plant — the curly leaf pond weed — which is not widespread so there could be benefits to removing that now. Also part of that first priority would be to control weeds along the western, northern and southwestern lake shoreline. The next priority would be the southeastern shoreline and around the island. “There’s nobody really complaining about the stuff around the island because hardly anybody gets out there,” he said.
The plan is to stay 400 feet from the Nile Golf Course shoreline so that lake irrigation used for the golf course isn’t impacted by the herbicide, he said.
Citizens are invited to learn more about the aquatic vegetation management plan during a public meeting set for 7 p.m. Tuesday, Sept. 11 at the Mountlake Terrace Senior Center at Lake Ballinger Park.
“It’s too bad we can’t find a way to eat milfoil,” joked Councilmember Rick Ryan. “We’ve got to do something, otherwise it’s just going to overtake.”
Another issue, noted Mayor Jerry Smith, is that boat owners often bring the invasive plants into the lake from other lakes. Part of the program will be in install signs at the lake’s boat launch informing boat owners not to launch in Lake Ballinger if they are carrying the plants on their boats, Smith said.
As for the Transportation Improvement Program, City Engineer Jesse Birchman told the council that the elements contained in the plan are a continuation of those in the 2018-2023 TIP. These include pavement preservation, sidewalks and sidewalk ramp construction; traffic signal equipment upgrades; bicycle route development and an intersection improvement at 200th Street Southwest and Highway 99 in coordination with the City of Edmonds. The plan also includes signal construction projects together with completion of the Main Street Revitalization project.
You can see a complete report on the proaposed TIP updates in the council memo here.
Tuesday night’s meeting will begin at 7 p.m. Tuesday, Sept. 4 in interim Mountlake Terrace City Hall, 6100 219th St. S.W., 2nd floor. You can see the complete agenda here.