WEASELHEAD RING ROAD IMPACT STUDYCategory: 2017, Community Grant, Completed, Grant, Land Use
Construction of the South West Calgary Ring Road (SWCRR) started in fall 2016. A section of the highway runs along the western (upstream) boundary of the Weaselhead Natural Environment Park, located at the head of Glenmore Reservoir in Calgary. The highway will cross the Elbow River floodplain on a ~10m high, one kilometer long earthen embankment. Three 145m long parallel bridges (north carriageway, south carriageway, and local road) will be built where the highways cross the river. To allow for this design 1.2km of the Elbow River will be redirected to a constructed channel and the original channel filled in. Two stormwater ponds will be built upstream of the bridges to collect runoff from east and west sections of the road and the Glenmore Trail interchange before discharge to the river. The highway is expected to carry 80,000 to 100,000 vehicles/day upon completion in 2021.
The Environmental Impact Assessment for the SWCRR details the expected impacts to terrestrial and aquatic habitats upstream and downstream of the Elbow River crossing. The mitigation measures proposed, should they be successful, were considered by the Province to render the expected negative impacts acceptable when compared with the financial costs of alternative designs. In this context, the Society initiated the SWCRR Impact Study. The objective of the Study is to assess the impacts of the SWCRR on ecosystems in the Weaselhead from construction to completion and to evaluate the actual success of the mitigation measures adopted.
Baseline data prior to disturbance was collected in 2015/16. Habitat clearing, river channel excavation/armouring/bio-engineering, and road-bed grading will take place in 2017 and we wish to collect data again, employing the same sampling and analytical methods. The long-term aim of the Study will be to have comparable baseline data, construction phase data, and data from once the road is operational in 2021. This project will support the second year of data collection during the ‘construction’ phase.
Success of the project in the short-term will lead to a reduction of negative environmental impacts on the Weaselhead. Monitoring will provide early indications of negative impacts on terrestrial and aquatic ecosystem components and allow timely action to correct or improve mitigation.
Success in the long-term will be a detailed understanding of the environmental impacts of such projects and the effectiveness of common mitigation measures. This knowledge will be available to inform discussion around similar projects.
*Photo courtesy of John Mader.