Elk/Beaver Lake Initiative,

Project Type

Initiative

Project Status

Current

Project Category

Regional Parks

Project Area

Saanich

What is the Elk/Beaver Lake Initiative?

The Elk/Beaver Lake Initiative was the beginning of a coordinated approach to address the high nutrient levels in Elk/Beaver Lake. The initiative included the creation of the Elk/Beaver Lake Watershed Management Plan [PDF/14.8MB] which was completed in 2020, and the installation, operation and maintenance of an in-lake remediation system (oxygenator) which was installed in late 2023.

The aim of this multi-pronged approach is to improve water quality, reduce frequency and duration of blue-green algae, and improve fish habitat. It is anticipated this approach will address both the immediate and long-term needs for the sustainability and health of the lake ecosystem and its many values.

The Elk/Beaver Lake Initiative was established by the CRD in 2016 in partnership with an Intergovernmental Working Group (IWG) and local interest groups. The aim of the initiative was to improve water quality at the lake, by reducing the frequency and toxicity of blue green algae, improve fish habitat, manage invasive weed growth and ensure continued recreational use of the lakes.

Elk/Beaver Lake is the most visited regional park, valued for its variety of environmental, social, recreational, and cultural benefits to the region. Water quality issues at Elk/Beaver Lake were identified in the 1960s and water quality continued to decline, having significant impacts on the environment, social, cultural and recreation values of the lake and surrounding park.

In response to declining water quality, the Intergovernmental Working Group (IWG) was formed to discuss the lake system and develop a strategy to improve water quality. Membership of this group included the Ministry of Environment and Climate Change Strategy, the Ministry of Water, Land and Resource Stewardship, Island Health, the CRD, and the District of Saanich. Communications and collaboration with other local interested groups, lake users and stakeholders are ongoing.

The following environmental concerns at Elk/Beaver Lake were identified through this initiative:

Frequent cyanobacteria blooms
Invasive growth of Eurasian Milfoil
Poor habitat quality for native fish and other native wildlife

The cause of these environmental concerns is largely related to the high nutrient levels in the lake, particularly phosphorus.

High nutrients in the lake come from external and internal sources and significantly impact the health of the lake overall. The impact of high nutrients in Elk/Beaver Lake is summarized in the following infographic:

Too Many Nutrients in our Lakes [PDF/3.3MB]

The current status of the lake and vision for the future protection of Elk/Beaver Lake is summarized in the following infographic:

Vision for a Healthy Lake [PDF/4MB]

The purpose of the Watershed Management Plan [PDF/14.8MB] is to reduce external sources of nutrients to support environmental, social and economic values of Elk/Beaver Lake.

External nutrients are carried by water, sediments and dust particles from sources outside of the lake and deposited into the lake. External sources include human activities such as land development, road construction and farming that bring additional nutrients into the lake and alter the movement of nutrients across the landscape.

The scope of this watershed management plan is geographically focused to Elk/Beaver Lake and the surrounding sub-watershed draining into Elk/Beaver Lake, to reduce sources of external nutrients.

In-lake remediation is guided by expert consultants. On September 11, 2019 a staff report and business case was brought to the CRD Board outlining the environmental, recreational, community and economic values of the lake (over $10 million annually) and a recommendation to remediate the lake. The CRD Board approved the recommendation to move ahead with an oxygenation system.

The construction of an oxygenation system and related components for Elk Lake was completed in late 2023. This system is helping to address internal nutrient loading in Elk Lake. These nutrients accumulated over decades in the lake and bottom sediments and were continually recycled back into the water column under low-oxygen conditions.

The total capital cost of the project was $1.6 million with additional annual operational costs related to water quality monitoring and system maintenance. The CRD is grateful for the Government of British Columbia's $750,000 contribution to help purchase the oxygenation system equipment.

The oxygenation system in Elk Lake pumps highly oxygenated air into the deepest part of the lake along a perforated pipe with small bubbles to improve deep water oxygen levels. This improves habitat for native fish and minimizes the opportunity for blue-green algae growth by reducing the availability of phosphorus in the water.

It's important to note that blue-green algae are native, naturally occurring organisms and it is not possible to entirely eliminate their presence in Elk/Beaver Lake. The main aim of the oxygenation system is to reduce duration and frequency of blooms and gain gradual water quality improvements over the next 5-10 years. It is not anticipated that the oxygenation system will improve the presence of invasive species in the lake, such as Eurasian milfoil (weeds).

Is the oxygenator working?

Data tells us that the Elk Lake oxygenation system is improving deep-water oxygen levels, reducing phosphorus and helping to maintain optimal water temperatures. Blooms have persisted largely due to climate-related impacts, namely warmer temperatures and drought, followed by heavy rainfall events that carry nutrients from the land into nearby water bodies.

Why develop a watershed management plan?

The purpose of the watershed management plan is to reduce sources of nutrients within the watershed that contribute to high nutrient levels in Elk/Beaver Lake. The management plan includes identifying values, interests and priorities in and around the lake. It summarizes water quality issues and sources of those issues and key management actions to address them.

What did the watershed management planning process look like?

Public engagement was a key part of developing the Watershed Management Plan for Elk/Beaver Lake. A public information session was held on July 31, 2019. Three additional feedback sessions were held throughout September and October 2019, as well as direct consultation with interest groups, field experts and government agencies.

The public were also invited to comment on the draft Elk/Beaver Lake Watershed Management Plan [PDF/14.8MB] through an online survey in February 2020 to support the finalization of the plan.

The management plan was finalized and approved in October 2020.