Road ecology and wetland improvements in Stony Swamp

The NCC has enhanced wetland habitats in the Stony Swamp Wetland Complex. This initiative increases the diversity of wetland habitats, supports more biodiversity and improves conditions for species at risk.

It is the result of close collaboration with the City of Ottawa to implement best practices to reduce road mortality and improve ecological connectivity, while meeting Ottawa’s transportation needs.

About the project

To accommodate rapid growth in Ottawa’s west end, the City is widening sections of roads through the Stony Swamp sector of the Greenbelt. For over five years, the NCC has worked closely with the City to ensure the least possible intrusion on this important conservation area. The City’s project now includes a series of measures that limit and offset the impacts of the work.

Sustainable road design

Fences and wildlife crossings help protect wildlife, and connect habitats separated by roads. Data from road mortality surveys found that many turtles and snakes, many of which are species at risk, were being hit on the road near the wetlands. Sustainable improvements to the road include the following:

retaining walls in wetlands to reduce the road footprint
wildlife exclusion fencing
wildlife crossings
measures to improve water quality

These improvements benefit both humans and wildlife.

Wetland construction

Two wetlands have been created off-site to offset the impacts of road construction. Work include the following:

the removal of invasive species such as European common reed, European buckthorn and purple loosestrife
the improvement of overwintering habitat for turtles at risk
tree planting
landscaping enhancement

Overall, this project has a positive impact on the Greenbelt. It enhances habitat diversity, increases habitat for species at risk, particularly the Blanding’s turtle, and results in expanded wetland.

This project is consistent with the policy of no net loss of habitat, identified in the NCC’s Greenbelt Master Plan, which supports the federal policy on wetland conservation.

Process and timeline

The project started in 2013, and is now completed.

The NCC wrote a letter to the City of Ottawa detailing federal environmental concerns and requirements for the provincial environmental assessment for the Kanata South Link road-widening project.

The NCC reviewed and provided comments to the environmental study report. This led to discussions and negotiations regarding the possible enhancement of ecological linkages in Stony Swamp, including wildlife crossings and the application of road ecology principles.

In February, the NCC sent a letter to the City confirming its interest in the project. The road ecological principles were implemented in the design phase, with clear and proactive guidance as to NCC and federal requirements.

The NCC identified four possible wetland compensation sites.
In February, the NCC approved the Kanata South Link road-widening project.

Two wetland sites were selected by consensus, and designs were developed and approved.
In May, the NCC approved the wetland compensation project.

Winter: Removal of a limited number of trees, with clearing and excavation work targeting invasive species such as European common reed, European buckthorn and purple loosestrife.
Fall: Excavation to create ponds, tree planting, landscaping enhancement and environmental monitoring.

All wetland construction is scheduled to be completed by summer 2021.

Completion of the NCC’s wetland monitoring report.

About the site

Stony Swamp is one of the most ecologically diverse protected areas in the Ottawa Valley. A mere stone’s throw from densely populated communities, Stony Swamp hosts many species that need to move around to maintain a healthy population. Snakes and turtles are often the most vulnerable to vehicle strikes. From the NCC’s four years of study on road mortality, problem areas have been identified across the Greenbelt. In Stony Swamp, seven eco-crossings are in place to allow these creatures to have safe passage to and from different parts of this sector.

Road mortality results showed some species at risk, such as Blanding’s turtles and milk snakes, were being struck by vehicles along this road. It is predicted that wildlife fencing will reduce these numbers by 70 percent.

Wetland construction will take place at two Stony Swamp locations near the Lime Kiln Trail (P10), as well as south of West Hunt Club Road and east of Moodie Drive (south of P11).