Water Retention on the Canadian Prairies

As climate extremes become more frequent, strengthening water storage across the Canadian Prairies is critical. Decades of drainage and landscape alteration have reduced the natural capacity of watersheds to capture and hold water, increasing vulnerability to floods, droughts, and water shortages. Using natural infrastructure to restore water retention helps rebuild this lost storage capacity while providing benefits for communities, ecosystems, and the economy.

IISD is advancing water retention solutions by conducting applied research to better understand how project design influences water storage, nutrient reduction, and watershed resilience, and to provide practical guidance for future implementation. 

What is water retention?

Water retention is the ability of landscapes to capture, store, and slowly release rainfall and snowmelt. It includes conserving and restoring natural features such as wetlands, floodplains, grasslands, and riparian areas, as well as constructing water retention projects with small dams to mimic natural processes. Unlike traditional grey infrastructure that temporarily holds water, water retention provides long-term storage while delivering multiple benefits such as flood protection, water supply, habitat, and improved water quality.

Where can we see water retention in action?  

Water retention projects are growing across the Canadian Prairies, with hundreds of wetland restoration and constructed storage projects already in place across Alberta, Saskatchewan, and Manitoba to increase watershed storage capacity and improve resilience to floods and droughts.

Watch this video to learn about a water retention and reforestation project on Futura Farms, in Manitoba, with support from the East Interlake Watershed District:  

What are the benefits of water retention?

Water retention helps communities, economies, and ecosystems become more resilient to climate change by capturing and storing water across the landscape. By slowing the movement of water and increasing storage capacity, water retention measures can 

• reduce flood risk by slowing runoff and holding water closer to where rain and snowmelt occur, helping to reduce downstream flooding;
• increase water supply and reduce drought risk by enhancing groundwater recharge, maintaining soil moisture, and providing stored water for agricultural, municipal, and environmental needs during dry periods;
• improve water quality by trapping sediment and reducing the movement of nutrients and other pollutants into rivers, lakes, and reservoirs; 
• support wildlife habitat and biodiversity by creating and maintaining wetlands and other habitats that provide food, shelter, and breeding areas for plants and animals; 
• store carbon and support climate resilience through healthy soils and vegetation that absorb and store carbon while providing other ecosystem services; and
• generate economic benefits by supporting agricultural productivity, protecting infrastructure from flood damage, and delivering multiple benefits from a single investment.

Where can I learn more about constructed water retention?  

IISD is a leader in advancing knowledge and practice related to water retention across the Canadian Prairies. Through applied research, monitoring, modelling, economic analysis, and policy development, IISD has examined how constructed water retention projects and wetland restoration can reduce flood and drought risk while improving water quality, supporting biodiversity, and strengthening water security. This work continues to help build the evidence base for water retention as a key natural infrastructure solution and inform policy discussions and project implementation across the Prairies.