Lake Erie

Lake Erie, one of the Great Lakes and a treasure for all :

  • supplies more than 11 million people on both sides of the border with drinking water
  • is home to approximately 130 fish species
  • grows Ontario’s economy through tourism, agriculture, manufacturing and highly productive and economically important commercial fisheries

Algal bloom threats

Lake Erie is by far the smallest of the Great Lakes in terms of volume. It is experiencing harmful and nuisance algal blooms and low oxygen zones due to invasive species, the changing climate and too much phosphorus from sources such as:

  • excess nutrients lost from farmland entering streams, rivers and lakes
  • urban stormwater entering streams, rivers and lakes
  • sewage treatment plant discharges

Reducing the amount of phosphorus entering Lake Erie is the most accessible way to reduce harmful and nuisance algal blooms that can be harmful to human health and the environment.

While phosphorus is an essential nutrient for plants and animals, scientists agree that too much phosphorus magnified by invasive species and the changing climate is the reason why we have harmful algal blooms in the lake.

Canada-Ontario Lake Erie Action Plan

The Canada-Ontario Lake Erie Action Plan (LEAP) was launched in 2018. It is a joint effort between federal and provincial agencies and partners, including:

  • municipalities
  • First Nations and Métis communities and organizations
  • agricultural organizations
  • conservation authorities
  • non-governmental organizations

The plan aims to reduce phosphorus loadings to Lake Erie with the goal of decreasing harmful and nuisance algal blooms and low oxygen zones in the lake.

These conditions are impacting the lake ecosystem and well-being of Canadians. They cost hundreds of millions of dollars to the Ontario tourism and recreation industries, property owners and water treatment operators.

Lake Erie phosphorus targets

A phosphorus load reduction target of 40% reduction from 2008 levels in phosphorus loadings to the western and central basins for Lake Erie was established and adopted under:

This load reduction target will address harmful and nuisance algal blooms and low oxygen zones in Lake Erie.

To achieve the load reduction target, Ontario and Canada, with partners, developed and implemented the Lake Erie Action Plan. This plan is Ontario and Canada’s domestic action plan to reduce phosphorus loads to Lake Erie.  

Action areas

The Lake Erie Action Plan commits to five categories of action, including:

  • reducing phosphorus loadings
  • ensuring effective policies, programs and legislation
  • improving the knowledge base
  • educating and building awareness
  • strengthening leadership and co-ordination

The specific actions the plan commits to include:

  • limiting loadings from municipal sewage treatment plant discharges and better managing stormwater
  • encouraging effective techniques to keep phosphorus on farmland
  • restoring natural wetlands

The LEAP builds on our leadership and efforts to improve water quality and public health, including a response protocol if a suspected blue-green algal bloom (also known as harmful algal bloom) is reported.

Working together, we will reduce phosphorus loadings and harmful algal blooms in Lake Erie.

Learn what you can do to reduce harmful algal blooms and report a suspected bloom.

2024 LEAP Evaluation and Update Report

The LEAP Evaluation and Update Report highlights the actions taken by Ontario, Canada and partners to reduce phosphorus loadings to Lake Erie from 2018 to 2022, as well as recent updates from 2023 (where available).

The report also:

  • provides the latest information on phosphorus loadings
  • identifies challenges, lessons learned and priorities moving forward
  • includes a renewed a commitment to action moving forward

LEAP Status of Actions

The LEAP Status of Actions provides a summary of the collaborative actions taken by the province, the federal government and more than 30 partners to reduce the amount of phosphorus entering Lake Erie from the Canadian side of the border since 2018.

The Status of Actions highlights the following details for every action in the Canada-Ontario Lake Erie Action Plan:

  • progress to date
  • status
  • implementation partner(s)
  • links to partner programs, projects and findings 

2019 LEAP update

Since launching the LEAP in February 2018, Ontario and Canada, in collaboration with key partners and sectors, have been making progress in putting the plan into action.

Areas where we focused efforts in 2019 include establishing an Implementation Team, working with municipalities to better manage wastewater and stormwater impacts, working with agriculture on reducing phosphorus run-off, supporting wetland restoration in the Lake Erie watershed, and continuing to monitor and improve science.

Implementation team

Since 2019 the LEAP Implementation Team has overseen the successful implementation of the plan.

The implementation team is responsible for tracking, assessing and evaluating progress and providing broader engagement opportunities.

It is made up of provincial and federal agencies that led the development of the plan, First Nations and Métis communities, and partners who are contributing their own actions to the plan, such as Lake Erie conservation authorities, agricultural sector organizations, municipalities and non-governmental organizations.

Managing wastewater and stormwater impacts

We are continuing our work with municipalities in the Lake Erie basin to improve wastewater effluent quality and reduce phosphorus loadings through efforts such as optimization of wastewater treatment plants, and promotion of green infrastructure/low-impact development to improve stormwater management.

On-farm nutrient management

Effective management of nutrients such as manure and commercial fertilizer, water and soil will keep phosphorus on farmland and out of waterways. This is a critical part of the LEAP that requires collaboration between government and its partners, including agricultural associations and other organizations.

The governments of Canada and Ontario support action and progress through the federal-provincial-territorial Canadian Agricultural Partnership, collaborating with the agri-food sector to promote and implement Best Management Practices, under which Canada and Ontario allocated up to $61.2 million over five years (2018 to 2023) to address a range of environmental stewardship and climate change priorities.

For Ontario, this meant:

  • Providing financial support for the implementation of Best Management Practices. This included regionally targeted programming for the Lake Erie basin via the Lake Erie Agriculture Demonstrating Sustainability.
  • Providing financial support to agri-food sector organizations and collaboration projects supporting water quality and soil health outcomes. Many LEAP partners  received funding for research, planning, and outreach projects supporting Lake Erie environmental stewardship outcomes.

Ontario worked collaboratively with the agricultural sector on a number of industry-led initiatives to reduce phosphorus loss from agricultural sources in the Lake Erie basin, including:

  • The voluntary 4R Nutrient Stewardship program, which encourages producers to use the right source of nutrients at the right rate and the right time in the right place.
  • The Ontario Greenhouse Environmental Strategy working group to support compliance efforts.
  • The implementation of the Ontario Cover Crops Strategy to encourage the widespread adoption of cover crops to protect and improve soil health.
  • The Thames River Phosphorus Reduction Collaborative partnership that promoted a suite of effective land management and drainage solutions.
  • The Timing Matters peer-to-peer advisory committee that provided education and awareness to producers about the risks of nutrient application on frozen or snow-covered ground.
  • A focus on proper field tile drain installation during contractor training and communications to minimize phosphorus movement to waterways.

In April 2018, Ontario released the New Horizons: Ontario’s Agricultural Soil and Conservation Strategy to help sustain and enhance soil health and productivity for economic, environmental and societal needs, which includes water quality.

In addition, Ontario supported research and innovation through the Ontario Agri-Food Innovation Alliance, the province’s agreement with the University of Guelph, which supports development of knowledge and technology to enable nutrient loss reduction from fields and improve soil health which will help to improve water quality in streams and groundwater.

Natural heritage

Ontario, in partnership with Ducks Unlimited Canada, supported wetland research to increase our level of understanding of the role that restored wetlands play in capturing and processing non‐point source phosphorus such as farm runoff. A detailed standardized wetland monitoring protocol was developed and applied to restored wetland basins in southwestern Ontario over a three-year period to assess phosphorus removal efficiency of these systems and to develop a predictive model to estimate the phosphorus mitigation and water quality benefits of new and restored wetlands.

In partnership with Ducks Unlimited Canada, Ontario worked with community partners to develop wetland restoration projects in the Lake Erie basin to restore lost wetland features or enhance those negatively impacted by competing land use pressures. Ontario invested $1.8 million in this initiative, with efforts being focused on improving the number and quality of wetlands in the priority areas identified in the Lake Erie Action Plan.

Monitoring and improved science

The adaptive management framework approach, which is informed by monitoring results and improved science, is a key element of the action plan. For instance, Ontario led a Multi-Watershed Nutrient Study to examine how agricultural land management and landscape features relate to phosphorus loadings from Lake Erie watersheds and how these relationships may have changed since the late 1970s. Ontario, with Canada, also assessed water quality and harmful algal blooms in Lake St. Clair and the Thames River, both of which feed into Lake Erie.

As part of its work to restore Lake Erie, Ontario has studied the impacts of phosphorus-driven algal blooms on fish reproduction, food webs and ecosystems of the lake. The results have supported an improved understanding of the dynamics of commercially important species (for example, walleye, yellow perch, etc.), and can also be used to predict impacts of algal blooms caused by excessive phosphorus loadings on fish and fisheries in Lake Erie.

Further details about progress in reducing phosphorus loads to Lake Erie are available in: