The Seine-Rat River Conservation District (SRRCD) recently completed a surface water assessment in the Roseau River watershed. The purpose of this assessment is to help communities develop sustainable surface water management strategies and increase understanding of how water flows into the Roseau River by creating an inventory of culverts located throughout the watershed.

This summer, the SRRCD partnered with the RMs of Stuartburn and Piney to collect culvert flow information on municipally managed culverts. Field staff used global positioning satellite (GPS) survey equipment to identify 2,175 culvert locations in the watershed. Staff also recorded elevation at the upstream and downstream end of each culvert, as well as information about culvert type (corrugated steel, plastic); restrictions (gate, apron); and culvert condition (torn, crushed, blocked, or altered pipe) for each municipality.

The GPS data collected throughout the surface water assessment can be analyzed using computer mapping software to show culvert locations and alignments for hydro-conditioning Digital Elevation Models (DEM). Hydro-conditioning refers to the process of using computer mapping software to accurately represent the flow of water across the contours of our landscape, including hills, valleys, cliffs, depressions, and even under roads. Hydro-conditioned DEMs can now allow us to accurately calculate where water will flow after a rain event. It is also possible to calculate the effects of changes on the landscape, such as replacing a small culvert with a large culvert. This means that the capacity to model surface water flows will give decision-makers better information on implementing sustainable surface water management strategies, including water storage and drought preparedness.

Water storage is important for slowing the flow of water to mitigate the effects of flooding on homeowners and agricultural land. Hydro-conditioned DEM surface water models are used to identify water storage sites in the watershed that are most beneficial to the community. Water storage and drought preparedness modelling are both currently being prepared by the province. Everyone agrees that the only thing worse than too much water is not enough water at all.

The inventory of culverts collected through the surface water assessment provides municipalities with information about the status of each culvert under their management. Municipalities can take short-term action to replace or maintain culverts identified in the inventory as no longer functioning due to damage, alteration, or blockages. The inventory also allows municipalities to develop long-term asset management strategies to optimize water management needs throughout the area by resizing or repositioning culverts, as well as replacing culverts that may be reaching the end of their design life.

The surface water assessment conducted by the SRRCD is a successful initiative that provides benefits to local municipalities in partnership with the district. The RM of Stuartburn recognizes the importance of these benefits for planning and decision-making.

Jim Swidersky, Reeve of the RM of Stuartburn, says, “Useful information is the lead to all projects because it increases the capacity for communities and local government to make more informed decisions.”

The SRRCD is pleased to partner with municipalities in our district by developing initiatives that benefit the health of our watershed. Feel free to contact our offices in La Broquerie and Vita for more information about the Roseau River Surface Water Assessment. We can be reached in La Broquerie at (204) 424-5845 or in Vita at (204) 425-7877. You can also visit us online at www.srrwd.ca.