The term riparian refers to the area at the interface between land and water. Riparian habitats are found along lakes, rivers, streams and wetlands. Restoring or naturalizing a riparian area is a process by which native species and ecosystem services are reestablished along a degraded riparian area.
Remove invasive species. In order to restore the area to its natural state and revive the ecosystem services it can provide, invasive species should first be removed where possible to allow native plants to become established.
Reinforce banks (if applicable). If banks have been eroded or destabilized by erosion and lack of root systems, slopes may be reinforced through soil bioengineering.
Plant native species. Native species becoming reestablished at the degraded site are critical to restoring the riparian zone’s potential to provide ecosystem services including flood attenuation, erosion mitigation, wildlife habitat and biodiversity.
Municipalities may need to consider whether they have expertise in-house or require consultation or collaboration with experts or other organizations with expertise in riparian management and restoration. The typical process for implementing this type of NBS includes:
- Stakeholder and community consultation. Engaging community members and stakeholders for awareness, education and buy-in is important to the success of the restoration.
- Site investigation and assessment. Riparian specialists may need to be engaged to assess the state of the area.
- Design and planning. Experts may be needed to advise municipalities on the best design for restoration of the riparian zone. Permits may be required and local, provincial and federal legislation should be taken into account when planning for the restoration. In Alberta, these laws include: provincial laws such as Municipal Government Act, Public Lands Act, Water Act, Forest Act and federal laws such as Fisheries Act, Migratory Birds Convention Act, and Navigable Waters Protection Act.
- Invasive species removal. These should first be removed where possible to ensure that native species can thrive in the area without being out-competed.
- Native planting. A diversity of native species should be planted to restore the ecosystem and the services it provides. Plants should be sourced locally where possible as these are most likely to be hardy.
- Monitoring and maintenance. Maintenance may include watering new plants until they are established. Monitoring the riparian area will ensure the restoration was successful and project planners can use adaptive management as the restoration progresses.
Depending on the extent of the degradation of the riparian area, the municipality may restrict access to the area to be restored until plants are established and soils/banks are stabilized, which may take years. Access may also be restricted or partially allowed for the long-term through bylaws, fencing, etc.
The Business Side
The cost of restoration is higher than that of protection before riparian areas become degraded. Projects may be funded through municipal budgets, grant programs, collaboration between municipal governments and stewardship groups and may also leverage community volunteer efforts to assist with removal of invasive species and planting of native varieties.
Riparian restoration provides value to the municipality by enhancing ecological health of the sites and renewing the ecosystem services they provide, which include flood and drought attenuation, improvements to water quality, and recreational and health benefits to citizens.
The Nature Side
Healthy riparian zones are biodiverse and restoring native vegetation to these buffer areas provides multiple ecosystem services. These include filtration of water entering waterbodies, which improves water quality for human and aquatic species uses, flood attenuation, greenhouse gas sequestration, erosion prevention and wildlife habitat.
The Community Side
Restored and naturalized riparian areas offer many benefits to communities. They help to reduce the risk of flooding, improve water quality and provide habitat for wildlife. Citizens living nearby or visiting restored riparian areas may have additional recreational opportunities, such as wildlife viewing and birdwatching, walking and biking (where permitted). As degraded riparian zones are restored, a municipality or developer can add nature to the community, which has positive impacts on human physical and mental health. Fully restored riparian areas are safer for people, property and infrastructure as they protect from flooding and stabilize banks that may be used for recreation and can increase property values in adjacent neighbourhoods.
Patton, C. 2020. Riparian restoration of 32E Greenbelt, along Quibble Creek, to enhance canopy cover and limit urban impacts within the wildlife corridor. University of Victoria.
South East Alberta Watershed Alliance (SEAWA). 2020. Riparian Restoration. SEAWA.