The Town of Gibsons is evaluating the conditions and potential risks to natural assets within the Gibsons Aquifer Watershed. By ensuring that natural assets are understood, measured, and managed, this project will support asset management strategies and climate change responses.
Until now, the Town’s natural asset management work has been restricted to eco-assets (such as the White Tower Park storm water ponds,) which exist within the Town of Gibsons’ boundaries (as indicated by the green line on aerial photo, top right).
The Source to Sea Project seeks to extend the scope of that work by evaluating the natural assets that lie within the entire watershed of the Gibsons Aquifer (as indicated by the pink line on aerial photo, top right).
This is considered to be a more ecologically relevant scale, as activity that impacts the natural assets within the watershed (but outside of Town boundaries) also impacts our community’s stormwater management, flood mitigation and drinking water services.
Natural assets in the watershed area which will be assessed include forests, streams, creeks, wetlands, urban parks and the foreshore.
The Source to Sea project area is the same as for the Town’s 2013 Aquifer Study, with the northern boundary set at the top of Mt. Elphinstone and the southern boundary at the Town’s waterfront. The western boundary includes the Chaster Creek watershed and the eastern boundary includes the Gibsons Creek watershed.
The overarching goal of the Source to Sea project is to ensure that the natural assets within the Town’s entire watershed are understood, measured, valued and, ultimately, managed to ensure their health.
Specifically, we seek to understand the current and possible future roles of the natural assets in providing:
- safe, reliable drinking water supply through the aquifer recharge;
- stormwater management services; and
- flood mitigation services.
Project goals include:
- establishing a baseline inventory of the natural assets that support water services;
- providing a condition assessment of the identified areas;
- understanding the level of service of the identified natural assets; and
- recommending best management practices of the natural assets identified.
Information collected on the Charman Creek Lands and Arrowhead Park through the scope of this project will provide staff and Council with the information required to make informed decisions regarding future uses of the forested areas. These areas provide stormwater functions through both the soils and the trees, and are included in the Town’s natural asset inventory.
Final outputs for the project are expected to include:
- Asset Registry Dashboard, with condition assessments complete
- Modelling of current conditions for prioritized natural assets in the watershed
- Uncalibrated service levels of prioritized natural assets
- Economic valuation of watershed natural assets
- Framework to connect Coastal Assets (Coastal Resilience Project) and Watershed methodologies (Source to Sea).
Data gathered through this project may also be used as inputs for the Aquifer Mapping Study update, and to support implementation of recommendations contained in the Town’s Integrated Stormwater Management Plan.
Phase 1 of the Source to Sea Project, in which an assessment of the natural assets (i.e. forests, wetlands and riparian areas) within the aquifer recharge area was undertaken, is now complete.
During Phase 2, the project team worked to identify potential risks to the natural assets and then model possible future scenarios in order to determine how to best protect them.
Potential risks to the assets include erosion, development pressure, invasive species, drought, deforestation, overuse of trails/unauthorized dumping of green waste in sensitive areas, flooding, forest fire, pollutant loading, drought, storm events, storm surge, sea level rise, and ocean temperature rise.
Through this work, it was determined that the natural assets that faced the highest number of risks were creeks (7 high risks) and riparian areas (6 high risks) followed by foreshore (4 high risks) and the urban forest (4 high risks).
The next phase of the project will be to model future scenarios, such as deforestation through logging or wildfire in the upper watershed, and then to assess the impact on the affected natural assets.
In July 2021, surface water monitoring stations were installed in Chaster, Charman and Gibsons Creeks, which all flow through the Gibsons Aquifer watershed.
The hydrometric stations will help staff determine the seasonal discharge values (i.e. water level and flow rates at different times of the year) and this information will be used to better understand how surface water (such as streams, creeks, ditches and rivers) may be recharging the Gibsons Aquifer. It will also provide insight into the ability of each creek to support aquatic life.
All hydrometric station data will be compiled and provided to the Town in digital format. Results will be shared with other organizations or consultants, to support other environmental initiatives such as creek modeling, discussion of fish habitat, etc. This is expected to benefit all stakeholders in the watershed.
During Q3 2021, staff and volunteers with the Sunshine Coast Streamkeepers received training from Waterline Resources in on-site data collection from all three hydrometric stations. Each station was surveyed, and baseline surface water conditions were recorded.
Moving forward, staff/Streamkeepers will record creek stage levels and creek discharge measurements over a range of creek flows, approximately 14 year. This data will be used to develop a creek discharge rating curve for use during watershed modelling in the future.
Concurrently, following noted erosion on some portions of Charman Creek, staff are developing a monitoring and maintenance plan for that waterway. Learn more about the Charman Creek Assessment here.
The Source to Sea project is being conducted in partnership with the Municipal Natural Assets Initiative, concurrent with its Managing Natural Assets to Coastal Resilience project.
Engagement and input will also be sought from:
- Sunshine Coast Regional District (drainage and watershed governance);
- Ministry of Transportation and Infrastructure (drainage);
- Ministry of Forests Lands and Natural Resource Operations / BC Timber Sales (aquifer and watershed governance); and
- First Nations (cultural and watershed governance).
This project was supported through the Healthy Watersheds Initiative, which is delivered by the Real Estate Foundation of BC and Watersheds BC, with financial support from the Province of BC as part of its $10-billion COVID-19 response.
The Interagency Watershed Plan (below) illustrates how managing the aquifer watershed requires effective collaboration across many jurisdictions and organizations.