Search Climate Insights Directory

The De Salaberry water retention project study (2019-2023) demonstrates that small naturalized dams can reduce phosphorus loads while mitigating floods and erosion, though performance varies based on retention time and incoming loads. The report argues that standard design practices often fail to maximize phosphorus reduction and recommends strategic targeting of phosphorus hot spots and increased retention times to better combat eutrophication and harmful algal blooms in Canadian freshwater systems.

The report evaluates 10 water retention projects in Manitoba's Seine Rat Roseau Watershed District, finding that such projects generally provide positive economic returns, particularly for livestock producers. While upfront construction costs are the primary expense, benefits include flood and drought protection, improved water quality, and operational efficiencies. A cost-benefit analysis indicates an average benefit-cost ratio of 3.16 for livestock producers over a 20-year period, though crop-only operations showed lower returns due to high initial costs and fewer on-farm co-benefits.

The document highlights that water retention projects in the Seine Rat Roseau Watershed District provide a 3:1 return in co-benefits to livestock operations and offer various operational advantages, supported by funding that can cover up to 100% of upfront costs.