This post was submitted by Chris Randall and Alan Wiebe of the Seine-Rat River Conservation District
The HyPro Water Retention was built in 2006 in partnership with HyLife Ltd. and the Seine-Rat River Conservation District (SRRCD). It is located south of Steinbach off of Herschfeld Road. The retention was designed to manage excess surface water run-off in the Tourond Creek watershed and reduce the effects of downstream flooding in the area.
The SRRCD monitors the effectiveness of its projects to ensure they will last well into the future. High water events over the years have breached the retention and caused flooding to the nearby land. Erosion gullies have also formed in places where water has overtopped the retention. We decided to refurbish this site to ensure it is better equipped to regulate medium to large rainfall events.
We installed a culvert reducer to the existing culvert to better regulate water retention at lower flows. The old, larger culvert rapidly released water into the stream outlet, causing flooding during small to medium rainfall events. The smaller culvert size will release water more slowly during similar rainfall events.
The site refurbishments also include the addition of a new spillway connecting to the stream outlet. It is designed to handle excess water during high water flows. Emergency spillways are an essential component of a water retention’s design because they can quickly discharge excess water and prevent erosion from compromising the integrity of the structure. We used fill from the excavation of the spillway to fix the erosion gullies that formed on the crest of the retention. The new spillway can handle twice as much water flow compared to the old culvert.
The re-design of the site incorporates a beaver prevention device that stops beavers from clogging up the culvert. It is larger and easier to maintain than the previous device we were using.
In addition to these features, the SRRCD found a unique way to save money on our project costs using an innovative new product.
Innovative Erosion Control Matting
The spillway was armored using an innovative erosion control matting by Armormax. The Pyramat High Performance Turf Reinforcement Mats utilize a unique three-dimensional design that promotes vegetative growth to reduce erosion. We consulted Nilex, a firm that specializes in geosynthetics, to help us find an alternative material to rocks. The Pyramat system is just as strong as rocks, cheaper to use, and is easier to install. The matting was installed with wire staples and duckbill earth anchors to ensure the system is just as strong and effective as rocks.
We were able to save significantly on project costs because the Pyramat system eliminated the need for us to haul rocks to this remote site. Hauling rocks to the site would have been very expensive and time consuming. We would have needed to hire extra equipment to handle the rocks and build a temporary road through the swamp. The erosion control matting is packaged into rolls that are light enough to load onto a pickup and deliver directly to the project site. As a result, we were able to keep this project under budget, save on time, and reduce our carbon footprint on the environment without having to hire extra equipment.
The SRRCD will continue to evaluate the effectiveness of the Pyramat system and its potential to be showcased as a viable product for future use. We are always looking for ways to incorporate innovation into the design of our projects.
This project was funded through our conservation auction program and in partnership with HyLife Ltd.
Feel free to contact our office if you have any questions about the work we do. 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.