The term riparian refers to the area at the interface between land and water. Riparian habitats are found along lakes, rivers, streams and wetlands. Riparian setbacks are guidelines or bylaws specifying the distance required between a shoreline and development. They are developed to protect water quality, wildlife habitat and shoreline stability, reduce potential property damage and mitigate risks to public safety. Municipalities can establish riparian setbacks through bylaws, environmental reserves and conservation easements.
Recommended Practices
Riparian buffer zones. Maintaining a riparian buffer zone of undisturbed shoreline along waterbodies (e.g., lakes, rivers, coulees, wetlands, etc.) is recommended. Increasing riparian vegetation can assist in infiltration as it decreases the speed of overland water flow and also aids in sediment deposition. The riparian buffer zone can be divided into the inner or streamside zone, middle zone, and outer zone. The inner zone provides shade and maintains the integrity of the bank and aquatic habitat, while the middle zone provides filtration and infiltration of water. The outer zone provides initial filtration and prevents development from encroaching on the two more sensitive inner zones.[1]
Site-specific setbacks. The width of a riparian setback will depend on a site’s topography, vegetation, wildlife and soil characteristics. Areas with steeper slopes require greater setback distances from the water’s edge to allow sufficient time for filtration since steeper slopes increase the speed at which water flows and thus decrease the buffer contact time. As well, steeper slopes are more susceptible to erosion.
Shallow water tables. Where shallow water tables are a concern, there should be larger riparian setbacks. Contaminants to surface water may more easily pollute groundwater where the water table is shallow.
Non-native plants should be managed as weeds, as many are invasive and do not provide the same benefits to the riparian zone bank stability or habitat/forage for wildlife as native species.
Project Considerations
When considering developments near bodies of water, planners should be aware of legislation guiding the management of riparian areas. In Alberta, these include municipal bylaws, as well as federal and provincial legislation, including:
Federal
- Fisheries Act
- Migratory Birds Convention Act
- Navigable Waters Protection Act
Provincial
- Municipal Government Act
- Public Lands Act
- Water Act
- Forest Act
The Alberta Public Lands Act (Section 3) states that the Crown owns the beds and shores of naturally occurring lakes, rivers, streams and permanent, natural wetlands. In order to establish riparian setbacks as a nature-based solution, municipalities and developers need to establish where the edge of a waterbody is in order to measure the setback distance. Water levels fluctuate over the course of the year, from year to year and due to multi-decadal changes in water levels. It is wise to hire a qualified biologist with the technical and scientific expertise to determine appropriate setbacks.
While riparian areas offer important protection for water bodies, municipalities still need to understand and manage from a watershed perspective by reducing runoff, protecting upland areas and conserving wildlife habitat. Additionally, municipalities need to be prepared to work with any landowners whose activities have encroached on public shore lands.
Riparian setbacks may be sensitive to human uses and may be protected by municipal bylaws, fencing, etc. Where public access to riparian setbacks is appropriate, designating community access points to provincial and municipal shores can help minimize cumulative detrimental effects. Communal beaches, docks and swimming areas are recommended as alternatives to allowing multiple points of access to a shoreline, if any. Developers and regulators should work together to identify areas that are suitable for public access that will minimize habitat loss or environmental damage.
The Business Side
Protecting riparian zones can increase the property value of adjacent lands, thereby increasing tax revenues for municipalities. Healthy riparian areas also help to mitigate flooding, which can prevent risks/damage to property and infrastructure. Maintaining riparian setbacks can contribute to increased public safety, such as cleaner water for swimming, fishing and drinking and more stable slopes. Since shorelines are technically public property, municipalities may deem them too sensitive for public access and can protect them through the use of fencing, bylaws, etc. Where sites are suitable for human uses (i.e., recreation), allowing select public access to them reduces the municipality’s need to establish public beach areas.
Under Alberta’s Municipal Government Act, riparian areas are typically designated environmental reserves under the ownership and jurisdiction of the municipality in the event of a subdivision[2]. As such, any costs associated with protecting riparian areas through setbacks stem from the development and enforcement of any bylaws pertaining to development and not from land acquisition.
The Nature Side
Riparian setbacks protect water quality by protecting the riparian areas that help to filter stormwater runoff that may contain suspended sediment and nutrients such as nitrogen and phosphorus. Vegetation and microbial activity that occurs within riparian areas help filter out nutrients and other pollutants as well. Protecting riparian zones by establishing setbacks also increases biodiversity and wildlife habitat. Many species at risk depend on riparian areas for one or several of their life stages. Riparian areas are key in flood attenuation as they slow the flow of water during surges and major weather events.
The Community Side
The use of riparian setbacks help municipalities and developers protect riparian areas, which in turn may provide opportunities for recreation in urban areas and allow for residents to have increased interaction with nature, including wildlife and bird viewing and fishing. The use of riparian setbacks can support the protection of more natural areas in communities and this has a positive impact on mental, physical and social health in the surrounding area. The presence of healthy riparian zones and associated green space can also boost the property value of adjacent properties and surrounding neighbourhoods.
[1] Alberta Environment. 2012. Stepping back from the water: a beneficial management practices guide for new development near water bodies in Alberta's settled region. Government of Alberta.
[2] Province of Alberta. 2021. Municipal Government Act. Queen’s Printer of Alberta.
Alberta Environment. 2012. Stepping back from the water: a beneficial management practices guide for new development near water bodies in Alberta's settled region. Government of Alberta. Available online at: https://open.alberta.ca/publications/9781460100592.
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.
Province of Alberta. 2021. Municipal Government Act. Queen’s Printer of Alberta. Available online at: https://www.qp.alberta.ca/documents/Acts/m26.pdf.