Ottawa Faces Urban Tree Canopy Decline Amid Development Pressures

Ottawa’s urban tree canopy is projected to experience a flattening or potential decline before reaching its goal of 40 percent, according to city staff. Between 2017 and 2022, the city’s urban tree canopy decreased from 21.5 percent to 20.6 percent, while the overall tree canopy across the municipality rose from 34 percent to 36 percent. Staff have noted that this decline in urban canopy could fall within the study’s margin of error.

The most significant losses in the urban tree canopy occurred in suburban wards, primarily due to land clearing for new developments. Areas such as Stittsville, Riverside South-Findlay Creek, and Barrhaven West have seen reductions of 11.57 percent, 10.06 percent, and 9.21 percent, respectively. A memo from city staff highlights that ongoing development may lead to the urban canopy remaining flat or decreasing for the next decade.

“Retaining mature trees provides the greatest short-term benefit,” the memo states. “When removal is unavoidable, successful compensation depends on having adequate space, soil depth, and soil quality to support healthy new growth.” The immediate impact of removing a mature tree results in a loss for the canopy, while newly planted saplings take years to grow and contribute significantly.

Strategies to Enhance the Urban Tree Canopy

City officials are advocating for policy and regulatory measures to prioritize the tree canopy while balancing housing development and poverty reduction goals. The proposed new Zoning By-law aims to ensure adequate space for trees in new developments, promoting an increased supply of affordable housing.

“Continued involvement of forestry staff in development review and the implementation of the Tree Protection By-law will help make these policies effective,” the staff memo explains. Collaboration with the development industry is deemed essential to maintain a healthy tree canopy alongside an affordable housing supply.

The city has already initiated various actions through its Tree Planting Strategy to address tree losses. Key measures include a new program to replace 500 lost trees in 2025, with plans to scale up to 1,000 trees annually. Additional initiatives, such as the Plant Your Place program, aim to provide 1,200 larger saplings to residents in priority neighborhoods, alongside an expanded Tree Dedication Program and large-scale tree planting in parks in collaboration with community groups.

Current State of Tree Canopy Coverage

Wards such as West Carleton-March, Rideau-Jock, and College boast the largest tree canopies, measuring 43 percent, 41 percent, and 40 percent respectively. These figures underscore the importance of maintaining and enhancing the urban tree canopy, particularly as development pressures continue in Ottawa.

As the city navigates the complex interplay of urban development and environmental preservation, the focus remains on sustainable strategies that will benefit both the community’s housing needs and the urban landscape. City staff emphasize that without effective policies and ongoing community engagement, achieving the target canopy coverage may face significant hurdles in the coming years.