Vancouver Lake’s long-standing water quality issues, particularly its recurring harmful algae blooms, were back before the Clark County Council on Wednesday, July 23, as staff presented a detailed overview of potential solutions for lake flushing, beach management and long-term governance.
The lack of funding for a third phase of the Vancouver Lake Management Plan, following Gov. Bob Ferguson’s veto of a $300,000 legislative provision earlier this year, will make addressing the health and viability of Vancouver Lake difficult for Clark County.
Ongoing management of Vancouver Lake
Public Works Clean Water Division Manager Devan Rostorfer led the work session by outlining the results of the Vancouver Lake Management Plan’s second phase. The presentation focused on ongoing efforts to mitigate toxic algae blooms, which force beach closures and pose health risks during the summer. She noted last summer’s peroxide-based algae treatment at the lake’s swim beach had mixed results.
“This treatment came with successes and challenges, primarily due to some unforeseen permitting needs,” Rostorfer said. “...The duration of the treatment was impacted and it was difficult to discern if the changes in the algae at the beach were due to the treatment or due to the wind patterns and the natural movement of the water and algae throughout the lake each day.”
Consultants evaluated four early-stage concepts to enhance water circulation by modifying or supplementing the Vancouver Lake Flushing Channel, which connects the lake to the Columbia River. Improving the southward water flow is crucial to mitigating harmful algae blooms.
“Modifying the Flushing channel has been identified as the number one long-term solution to sustain water quality into the future,” Rostorfer said.
Flushing channel options presented
Option 1A would replace the existing culvert with an open channel bridge, allowing bi-directional flow between the Columbia River and Vancouver Lake. It carries a projected construction cost of $21 million.
“The model results (show) significant improvement in water clarity and reduced, harmful algal bloom days for both Lake River and Vancouver Lake,” Rostorfer said.
Option 1B adds a backflow preventer to the bridge, at an increased cost of $33.5 million. It would allow unidirectional flow during the summer, reducing nutrient-rich water from Lake River from entering the lake.
“Preventing that backflow into Vancouver Lake is really important,” Tim Clark, a leading consultant from Herrera Environmental Consultants, said. “That’s just a really nutrient-rich slough, and so preventing that backflow into Vancouver Lake is really important.”
Option 2A would use above-ground pumps to pull water from the Columbia River into the lake. Although less costly to build ($18.7 million), it would require an estimated $410,000 annually for electricity and maintenance.
“From a water quality perspective, this effort does result in reduced harmful algal bloom days in both Vancouver Lake and Lake River,” Rostorfer said.
Option 2B includes the pumps from 2A plus a weir structure to retain higher water levels in late summer and further limit nutrient backflow. The most expensive plan presented carries an estimated $41.7 million construction price tag and $450,000 in annual operating costs.
“This control structure is really looking only to be raised during the months in which Lake River elevation due to tidal influence would be higher than that of Vancouver Lake,” Clark explained. “So in terms of that prevention of the nutrient loading, it would be the most effective at decreasing that load.”
While all four concepts would improve water quality to varying degrees, no preferred option has been selected.
“At this stage, no preferred alternative has been selected or recommended,” Rostorfer said. “We have just evaluated very preliminary options.”
Council members expressed strong interest in advancing flushing enhancements and maintaining the lake’s beach for swimming.
“I think this is something that is very critical,” Councilmember Glen Yung said. “If there’s one thing that I want to get done during my time on this council… it would be this … get this set up, get it fixed and done so that people can return to their lives and enjoy the lake.”
County Chair Sue Marshall emphasized the need for reliable, ongoing funding for aquatic invasive species treatment and water quality improvements.
“If we treat milfoil one year and we don’t know where the next treatment will be funded from… you’ve wasted the previous treatment,” Marshall said. “It has to be an ongoing regime.”
Councilors also stressed the importance of preserving swimming as an intended use of the lake.
Long-term governance and funding remain unsettled
Without phase 3 funding from the state legislature, advancing flushing enhancements and continued planning may require new governance and funding structures.
“We’re uncertain about eligibility for funding to continue the work,” Rostorfer said.
Staff presented two possible frameworks: a flood control district or a flood control zone district. Establishing the former would require a public vote and be governed by an elected board, while the latter could be established by council resolution and governed by the council.
If either district model were established, funding could be generated through a variety of rate structures, including uniform parcel charges, assessments based on property value, or more targeted methods such as drainage basin impact or impervious surface area, similar to how the county’s existing stormwater and clean water fees are assessed.
Some council members were open to exploring either model to consolidate fragmented responsibilities and allow for long-term planning and budgeting.
Additionally, some councilors suggested exploring a possible increase to the county’s existing Clean Water fee as another funding option. That fee, currently applied to all unincorporated properties, has $100,000 per year budgeted for lake management across both Vancouver Lake and Lacamas Lake.
Council also requested that staff present the same findings to the City of Vancouver and Port of Vancouver to strengthen interagency coordination. The current intergovernmental agreement among the local jurisdictions expires in 2027 and would require a renewal.
“We want to continue to work with our local, state, and federal government partners to establish Vancouver Lake as a funding priority,” Rostorfer said.
The council signaled unanimous support to progress toward selecting a preferred flushing option, securing additional funding and coordinating treatment of invasive milfoil.
Staff said they will move ahead with hiring a dedicated lakes and watershed coordinator, using existing funds, to keep momentum going while pursuing state and federal assistance.
