How to Best Manage Water Retention Sites to Protect Manitoba’s Environment

The briefing emphasizes that strategic management of water retention sites—including engineered wetlands—is essential for Manitoba to mitigate risks from floods, drought, and nutrient loading. It details the importance of controlling retention times, water levels, and biomass harvesting to capture contaminants and support a local bioeconomy. The document highlights successful examples like Pelly’s Lake in Manitoba and North Ottawa in Minnesota, and calls for the use of Light Detection and Ranging data and clear management criteria to ensure the sustainability and effectiveness of these projects.

• Water retention sites are critical for reducing risks associated with floods, drought, and nutrient loading in Manitoba, but their effectiveness depends on strategic management rather than simple implementation.
• Effective management of water retention involves optimizing retention times to balance nutrient absorption and wildlife habitat with the need to drain sites by late August for biomass harvesting.
• Harvesting plant biomass from retention sites is necessary to remove captured phosphorus and carbon from the landscape and can support a provincial bioeconomy through renewable energy and livestock bedding.
• Case studies demonstrate the efficacy of engineered wetlands: Pelly’s Lake in Manitoba has removed over 5 tonnes of phosphorus, while the North Ottawa impoundment in Minnesota reduces nitrogen loads by 68 per cent and phosphorus loads by 54 per cent.
• To improve water retention outcomes, the author recommends the adoption of Light Detection and Ranging data for provincial topography, the development of clear management criteria, and the implementation of monitoring and measurement systems.

APA

International Institute for Sustainable Development (2017). How to Best Manage Water Retention Sites to Protect Manitoba’s Environment. https://www.iisd.org/system/files/publications/best-manage-water-retention-manitoba.pdf

Chicago

International Institute for Sustainable Development. How to Best Manage Water Retention Sites to Protect Manitoba’s Environment. 2017. https://www.iisd.org/system/files/publications/best-manage-water-retention-manitoba.pdf.

Wikipedia

{{cite report |author=International Institute for Sustainable Development |title=How to Best Manage Water Retention Sites to Protect Manitoba’s Environment |date=2017 |url=https://www.iisd.org/system/files/publications/best-manage-water-retention-manitoba.pdf |access-date=23 October 2026 |via=Climate Insights Directory}}

BibTeX

@techreport{internationalinstituteforsustainabledevelopment2017how, author = {{International Institute for Sustainable Development}}, title = {{How to Best Manage Water Retention Sites to Protect Manitoba’s Environment}}, institution = {International Institute for Sustainable Development}, year = {2017}, url = {https://www.iisd.org/system/files/publications/best-manage-water-retention-manitoba.pdf}, urldate = {2026-10-23}, note = {Indexed by Climate Insights Directory} }