Density bonusing is the practice of allowing flexibility in zoning laws (e.g., allowing developers the ability to increase the number of dwellings or units per area) in exchange for providing public goods. From an ecological function perspective, density bonusing can be used as a tool to encourage higher density neighbourhoods while protecting more natural areas and wildlife habitat. Density bonusing is often used in conjunction with other land-use planning and conservation tools, such as conservation design (see Conservation Design) and conservation easements (see Transfer of Development Credits, Conservation Easements & Land Trusts).
In Alberta, Direct Control District designations allow municipalities to “regulate and control the use or development of land or buildings in the district in any manner it considers necessary.” As such, municipalities using these designations can emphasize the conservation of existing natural spaces in their communities.
These two tools have the potential to be used together to effectively modify zoning requirements to protect and conserve existing natural spaces.
Allow flexibility of density targets. It is recommended that municipalities allow flexibility in density targets through density bonusing and Direct Control Districts in order to achieve greater protection of natural areas and ecological functions.
Potential environmental considerations municipalities could request in exchange for higher density development include:
- Protection of continuous or contiguous areas of wildlife habitat
- Provision of trail networks to enhance neighbourhood walkability and recreational opportunities
- Provision of common green space
- Restoration of previously degraded natural areas such as wetlands, forests, or native prairie habitats
- Incorporation of on-site stormwater management and water recycling through NBS
- Incorporation of on-site energy generation and district heating and cooling
- Commercial spaces within and light industrial areas adjacent to residential developments to encourage live-work communities and reduce vehicle dependency
Match character of surroundings. As with cluster development (conservation design link), it is important to ensure that higher density developments are still within the character of the surrounding land uses and that their development is done in collaboration with and the support of local residents.
Consistent application. Density bonus zones can be incorporated into zoning bylaws to ensure consistent application of the tool to target areas for conservation.
Collaboration with biologists. Professionals can help ensure a scientific approach to identifying target environmental assets for protection and to maximize the provision of ecological services through conservation of existing natural spaces.
The Business Side
From an economic perspective, density bonusing is a relatively low-cost way for municipalities to help achieve their environmental and social goals. Developers are able to obtain close to full market value for the residential sites they develop and receive incentives to provide public goods back to society and the municipality. Density bonusing may be an attractive option for landowners wishing to sell and/or develop, since this arrangement can still allow them to receive full or near market value for their land.
The Nature Side
When density bonusing is offered as an incentive tool for conservation of natural areas or other environmental features, it can help protect and restore numerous ecological functions on the landscape. For example, it can be used to conserve or restore wildlife habitat, increase biodiversity, protect groundwater recharge areas, conserve and reuse water, conserve energy, provide flood attenuation or encourage renewable energy generation. Long-term protection of natural areas can be achieved when density bonusing is combined with land securement via conservation easements (see Transfer of Development Credits & Conservation Easements links).
The Community Side
The social benefits associated with higher density developments are similar to those that stem from cluster developments (conservation design) and can include:
- Greater walkability and pedestrian activity, thereby reducing health impacts of inactivity and ultimately reducing associated health care costs
- More interactions amongst neighbours, thereby increasing the sense of community and public safety
- Recreational opportunities of nearby conserved natural areas, including wildlife viewing, walking, cycling, etc
- Increased property values associated with proximity to natural areas and green space
 Government of Alberta. 2021. Municipal Government Act. Section 641(2).
Government of Alberta. 2021. Municipal Government Act. Section 641(2).
Primeau, S., Bell, M., Riopel, M., Ewaschuk, E., & Doell, D. 2009. Green Communities Guide: Tools to Help Restore Ecological Processes in Alberta’s Built Environments. Land Stewardship Centre of Canada.
Taves, L. 2002. Density Bonus as a Tool for Green Space Conservation: An Evaluation of its Use in British Columbia’s Rural-Urban Fringe. Simon Fraser University.