Text Size

Integrated Watershed Management

Integrated Watershed Management (IWM) is the process of managing human activities and natural resources on a watershed basis. This approach allows us to protect important water resources, while at the same time addressing critical issues such as the current and future impacts of rapid growth and climate change.

Our activities on the land impact the health and sustainability of natural resources and can threaten how much water we have available as well as how well we can adapt to the impacts of climate change. The best way to protect resources is on a watershed basis using an integrated watershed management approach. This approach allows us to address multiple issues and objectives and enables us to plan within a very complex and uncertain environment.

Learn more reading Conservation Ontario's IWM Backgrounder

An Integrated Watershed Management Approach to Great Lakes Protection: Conservation Ontario Recommendations for a Great Lakes Protection Act" (April 2012)  Fact Sheet     Report

Integrated Watershed Management
Navigating Ontario’s Future

Ontario faces significant challenges in maintaining water quantity and quality. While grappling with a number of multiple stressors such as climate change, intensified urbanization and growth, pollution and introduction of exotic and invasive species, watershed managers need to balance the water needs of business and citizens while at the same time guaranteeing that enough water is actually remaining on the land to meet the ecological needs of our environment.

Integrated Watershed Management (IWM) is an approach that recognizes and operates based on the interconnectedness of ecology, economy and society. In doing so, we are able to ensure that adequate supplies of good quality water are maintained for the entire population while still preserving the hydrological, biological and chemical functions of ecosystems.

In order to improve our understanding of Integrated Watershed Management, a shared initiative was undertaken by Conservation Ontario (represents Ontario’s 36 Conservation Authorities), Fisheries and Oceans Canada and the Ontario Ministries of Natural Resources and Environment to review IWM leading to recommendations on how to update our approach to IWM in Ontario.

The initiative, entitled Integrated Watershed Management: Navigating Ontario’s Future presents a series of three main reports plus a Summary Report. These include:

IWM Summary Report

Main Reports     
Integrated Watershed Management
in Ontario

A Water Management Framework
for Ontario

A Water Budget Overview
for Ontario

Appendix 1
Appendix 2
Appendix 3
Appendix 4
Appendix 5
Appendix 6
Appendix 1


These reports begin by updating our understanding of IWM in Ontario; assessing it against IWM being conducted globally and nationally; identifying gaps; and recommending strategic shifts needed to address these gaps. From this research, we categorize a set of tools that could be applied to Ontario for planning and decision-making.

This initiative also explored the development of a Water Management Framework and conducted a Water Budget Overview for Ontario. Under the umbrella of IWM, the water management framework is intended as a practical guide that assists water management agencies to work to ensure a sustainable water resource for Ontario. The water budget assessment is one component of many within the water management framework.

IWM and Climate Change

Ontario’s water resources are at particular risk from climate change. Rising temperatures and changing precipitation patterns in Ontario have already reduced river flows, warmed surface waters and dried out wetlands. These impacts will likely continue, and other threats to environmental and public health are expected to materialize, including increased flooding and diminished quantity and quality of drinking water.

IWM is the process of managing human activities and natural resources in an area defined by watershed boundaries. It is an evolving and continuous process through which decisions are made for the sustainable use, development, restoration and protection of ecosystem features, functions and linkages. Integrated watershed management allows us to address multiple issues and objectives; and enables us to plan within a very complex and uncertain environment.

Taking an integrated watershed approach to dealing with the water and related resource management issues can be a much more efficient and effective response than coming to terms with individual issues.

10 Years After Walkerton
Protecting Municipal Drinking Water Sources

(Excerpt from an article published by Conservation Ontario in March 2010 Municipal World Magazine)

This year marks the 10th anniversary of the Walkerton Drinking Water Tragedy. The effects are still felt today by a number of Walkerton residents.

In the intervening years, Ontario’s system of managing and protecting municipal drinking water has undergone a complete overhaul. One of the key elements of the new system was laid through the Clean Water Act and the subsequent Ontario Drinking Water Source Protection Program.

Looking back from 2010 there are obviously many lessons to be learned from our experiences in Walkerton. Two key lessons include:

Lesson One
Humans are part of the environment. Our society is not, and cannot, be isolated from the environment in which we live.

Lesson Two
Taking a fragmented, issue-based approach to managing our environment is time consuming and expensive.

A broader planning, policy and program approach called Integrated Watershed Management recognizes these important interconnections and is increasingly being adopted in Canada. Ontario’s Conservation Authorities already rely on this approach to help manage the province’s natural resources.