Guided walking and kayaking tours showcasing green infrastructure in and around the Courtenay River were held on May 10 and 11, 2019. The tours were geared towards increasing political awareness of the possibilities of green infrastructure. Participants visited areas where green infrastructure was already in place or where it could be implemented in the future. It was an invite only event with invitations to our regional elected officials from the City of Courtenay, Town of Comox, Village of Cumberland, K’omoks First Nations, school district #71 trustees, Member of Legislature and Members of Parliament as well as ‘neighbours of the river’ and other land use decision-makers such as engineers, architects and developers.

What is Green Infrastructure?

Green infrastructure is a term for the natural vegetative systems and green technologies that collectively provide society with a multitude of economic, environmental and social benefits. They are also called natural assets, eco-assets or blue-green infrastructure. Most importantly green infrastructure sustainably manages our rainwater. Green infrastructure includes: urban forests, wetlands, bio-swales, engineered wetlands and storm water ponds, waterways and riparian areas, meadows and agricultural lands, green roofs and green walls, parks, gardens and grassed areas, it can also include technologies like porous pavements, rain barrels and cisterns. In a natural environment, rain is absorbed and filtered by pants and soils. In urban landscapes, this natural water cycle is disrupted and rainwater flows across pavement and rooftops. Traditional development alters natural systems to fit into engineered infrastructure and water is conveyed away as quickly as possible. This water picks up pollutants, speed, and volume as it runs across these impervious surfaces and into the nearest waterbody. This is not ideal for the local environment or its associated species. Green infrastructure brings nature into the City, to capture and clean our rainwater before returning it to the surround oceans and rivers. Green infrastructure requires a new decentralized, site-specific approach, and a reliance on a team with expertise beyond engineering. It will require clear community and political support or a change in provincial policy to move beyond the status quo.

The aim of the tours was to encourage politicians, engineers  and school trustees to work together with biologists and ecologists to develop an overall green infrastructure vision for the Comox Valley to deal with issues such as flooding and rainwater management.

What is a Floodplain?

A floodplain is the lowland area adjacent to a river, lake, creek or ocean. When floods occur water flows onto these nearby low-lying areas. When floodplains are preserved in their natural state, or restored to it, they provide many benefits to both human and natural systems.

Green floodplain infrastructure focuses on flood resiliency not flood protection – it is not about preventing the flood (the damming solution) but about allowing it to occur naturally without causing dangerous or expensive damage. Allowing for infiltration and allowing the waters to recede quickly when flooding does occur. What this type of green infrastructure doesn’t do is prevent all flooding from occurring or protect all existing development from being flooded (development built in natural floodplains). Natural flood relief relies on the ecosystem rather than built infrastructure meaning lower costs and maintenance. Grey and green infrastructure can work together to protect build features and a variety of flooding scenarios.

Tour Stops (stars on map)

#1 Airpark Lagoon – This is an example of altering the natural system to fit into engineered infrastructure. The area was diked and the sewage lagoon created in the 1950s. The lagoon didn’t work properly and polluted the estuary.  Operations ceased in the 1980’s. In the early 1990’s it was dredged, the south end was breached, and the Airstrip was created. This work was in compensation for the expansion of the Comox Marina.

In 2015 Project Watershed breached the top end to allow the river to flow through, improve circulation and water quality. Now it is serving as green infrastructure, providing habitat for salmon and other species, area for flood attenuation and is an eco-asset for the community.

#2 Courtenay Marina – This is actually where the Courtenay river used to divide into two branches and one branch came through the marina and joined with the Airpark as shown in the picture.

Currently there is no green infrastructure in place here. Stormwater runoff can carry sediments, chemicals, pathogens, and litter straight into the river. Marinas that can’t manage stormwater efficiently are at higher risk of flooding, erosion, water contamination, and sewage problems. Green infrastructure installations like rain gardens, porous pavement, and green roofs can be used to slow, capture, and filter rainwater and snowmelt before they enter the river.

#3 Riverstone Condominiums – The wetland compensation project at Riverstone aimed to recreate a natural system. However, an already exisiting Sitka Spruce wetland that was providing wetland services and was home to green herons was replaced by the recreated natural system. Yes, what was built does deal with some of the urban runoff but we have lost the green infrastructure that the forest provided and we haven’t replaced that. To date no green herons have returned. Compensation projects don’t always work, certainly are not the same as the original environmental features. Sometimes green infrastructure means supporting an environment that already exists and leaving it in place.

#4 Kus-kus-sum– In addition to creating habitat for fish and wildlife, restoring the site at Kus-kus-sum will create green coastal infrastructure that helps attenuate flooding as well as filter runoff and slow the release of stormwater into the river. It will also move some hard infrastructure out of the floodplain as a “managed retreat” – a progressive flood proofing strategy of allowing the river’s natural processes to play out in developmentally low risk areas.

From the City of Courtenay’s flooding report in 2012, the results of all the options show that flooding is pushed upstream with less use of the floodplain. However, we believe we should see an increased use of the lower floodplain as that will provide flood relief and reduce impacts on the community, which would be demonstrated in part by fewer insurance claims.

#5/6 Lewis Park, Simms Park and the Courtenay Slough – Simms Park and potentially Lewis Park and Courtenay Slough could provide green riverine infrastructure that would make room for flooding to occur naturally, allowing water to flow instead of ‘damming’ it back. It would also slow down the water flow and temporarily store it. Fish passages become an important aspect of the flood relief infrastructure. The side channels that Project Watershed enhanced to be better fish habitat in Simms Park can function as flood relief. Increasing flood relief connections through Lewis Park and the Courtenay Slough would give floodwaters space and allow them to dissipate quickly. Some potential ideas are depicted in the diagram below. More information on flooding and ideas for mitigating local flood events can be found in Understanding and Restoring Floodplain Functioning to Mitigate the Impacts of Land Use a presentation Jennifer Sutherst, Project Watershed Staff Biologist, gave to the Courtenay Eco-asset Symposium in 2014.

Thanks to our community sponsors:

  • Airpark Cafe
  • Courtenay Airpark Association
  • CV Kayaks

Thanks to our tour guides:

  • Graham Hill. P.Eng., Northwest Hydraulic Consultants
  • Jennifer Sutherst, Estuary Coordinator & Staff Biologist, Project Watershed
  • Caila Holbrook, Manager of Fundraising, Outreach and Mapping, Project Watershed
  • Dan Bowen, Director, Project Watershed
  • Don Castleden, Director, Project Watershed

This event would not have been possible without the participants! Thanks to the elected officials representing the City of Courtenay, Town of Comox, Village of Cumberland, North Island-Powell River MP and Wedler Engineering LLP. And lastly, thanks to Kathy, Gabrielle and Lona for providing kayak safety and to all of the early morning volunteers who helped greet the participants.

Project coordinated by Sonya Jenssen, M.A., http://waterwoman.ca/

Thanks to our tour sponsors