Table discussion interpreted by Sundaura Alford-Purvis.

“The Tangled Garden”, by J.E.H. MacDonald, 1917.

Priority: Provide legal and enforceable protection for biodiversity in the new Official Plan.

As with most communities, the city of Ottawa relies heavily on the services provided by the natural systems within and surrounding our community. From a fiscal and public safety standpoint, healthy soil and extensive green cover mitigate flooding,(1) limit cooling costs and capture the microparticles and combustion gasses that contribute to premature death of an estimated 14,600 Canadians every year. (2) From a social and public health standpoint, access to natural spaces reduces stress, improves mental health and encourages more active lifestyles. (3) Given these contributions to society, the health and biodiversity of the ecosystems that we rely on must be legally protected for Ottawa to continue to thrive.

Policy actions:

  • Create an inventory of existing ecosystem services that the city relies on, including land areas and ecosystems that assist in flood and drought mitigation, urban cooling, biodiversity protection, community and social activities and air quality maintenance. Include public, institutional, corporate and privately held land in this inventory to ensure that it accurately represents the services we currently depend on.(4)
  • Establish metrics for evaluating the health and diversity of ecosystems and monitor how activities that take place near or within those ecosystems alter their ability to provide the services the city depends on. When evaluating urban green spaces, expand from a tree canopy focus to a complete ecosystem/biodiversity focus, including soil health, to fully capture the services we rely on them to provide.
  • Establish firm, legal protections for existing biodiversity, regardless of location, and mandate a zero net-loss of biodiversity and ecosystem function when land use is changed or new construction undertaken. A zero net-loss lens allows for the implementation of a range of options for meeting the intended goals, including directing construction to areas where ecosystem and soil health is already compromised, incorporating high value, dense ecosystem plantings into new neighbourhoods and around new buildings and greening building surfaces with green roof and/or wall surfaces.
  • Identify city infrastructure service needs that can be met with living green infrastructure and prioritize those solutions over grey infrastructure. This will have the compounding benefit of incorporating small pockets of green space throughout dense urban areas, which often have a deficiency of publicly accessible green spaces. Living green infrastructure has also proven to be less expensive than equivalent grey infrastructure, to contribute to the creation of more jobs, and to be associated with improved public health outcomes and reduced crime rates.(5)
  • Identify and actively promote under-utilized existing programs and resources for increasing biodiversity, soil health and green cover on privately owned sites and develop plans for increasing public awareness of the importance of these programs and how to access them.(6)
  • Encourage the implementation of green infrastructure on privately owned lands by implementing an ecosystem services surcharge, with increased fees for large areas of impermeable or heat absorbing surfaces and decreased fees or providing other forms or compensation for on-site storm water infiltration, extensive foliage cover and high levels of overall biodiversity.(7)

Immediate steps: Identify and document the existing ecosystem services that we rely on to support critical services, moderate energy use and protect human health and incorporate this information into urban planning and climate change planning.

Identify areas with existing tree canopy, and/or other foliage, insufficient to effectively filter and cool the air. Develop community specific projects for correcting this, such as green roofs and walls, or vine covered shade structures where trees aren’t feasible, as well as de-paving projects and community garden boxes. Seek living green infrastructure solutions as preferred solutions on all city infrastructure installation, upgrading or replacement as an additional means of meeting green-cover targets.

Reaffirm and implement current municipal and provincial policies establishing a target that in residential areas, all homes will be within 400 metres of a greenspace, or roughly within a five-minute walk.

Linkages with other priorities: 

Protecting biodiversity and ecosystem services directly relates to the protection and expansion of greenspaces (see Nature posts) and the creation of multifunctional urban landscapes that include food producing plants (see Food posts).(8) It will also help to increase neighbourhood walkability, with the associated reduction in car(bon) based transportation, by making outdoor spaces healthier and more comfortable (see Building and Transportation posts).

Fostering community-level agency in use of, and care for, green spaces, with the city providing staff support and guidance for community-level initiatives, can contribute to changing our implementation and accountability culture (see Accountability and Implementation posts). Replacing ‘low maintenance’ public landscapes with interactive landscapes that rely on the care of community members to thrive can maximize the public and mental health benefits of public green spaces by promoting direct engagement and allowing people see how nature can thrive with human assistance, rather than only suffering from our presence (see Nature posts).


  1. Flood mitigation through natural infrastructure http://www.ibc.ca/on/resources/studies/natural-infrastructure-is-an-underutilized-option
  2. Air quality and Canadian’s health https://www.canada.ca/en/health-canada/services/air-quality/health-effects-indoor-air-pollution.html
  3. Urban green spaces and health https://www.who.int/sustainable-development/cities/health-risks/urban-green-space/en/
  4. Ecosystem services Toolkit https://biodivcanada.chm-cbd.net/documents/ecosystem-services-toolkit
  5. Philadelphia green infrastructure research https://www.bizjournals.com/philadelphia/news/2019/05/24/green-stormwater-infrastructure-philadelphia.html
  6. Underutilized city programs https://ottawa.ca/en/living-ottawa/environment/trees-and-forests/tree-planting
  7. Tiered fees based on site conditions http://www.omwa.org/water3/test/
  8. Growing food crops in urban soils: https://www.cerema.fr/system/files/documents/2017/12/pollusols_web-2%20%281%29.pdf