Phase 3 – Scenarios Report (5.3Mb PDF)
This report summarizes a selection of Okanagan Basin water supply and use projections for 2011 to 2040, based on Phase 3 modeling using the Okanagan Basin Water Accounting Model (OBWAM) and its supporting models, the Okanagan Basin Hydrology Model (OBHM) and the Okanagan Water Demand Model (OWDM).
Simulating Okanagan Water Futures
A key outcome of the project is the successful development of Okanagan-specific state-of-the-art computer modeling tools that can simulate future water conditions in the Okanagan, and estimate the influence of climate change and human decisions on water use and stream-flows.
For the first time, these models provide a way to determine how a decision made in one area of the Okanagan Basin can affect another area of the basin.
The project includes 15 scenarios of climate change, land use alternatives and population growth – only a small sampling of the range of possible water futures that illustrate the power of this tool.
The work has highlighted the important role – and limitations – of demand management in adapting to climate change, the challenges that face water suppliers in providing reliable supplies into the future, and the importance of proactive decision-making to secure a sustainable water future for the Okanagan.
It also points out knowledge gaps where further research and monitoring are needed.
Some 15 climate, land-use and population growth scenarios were examined. The scenarios considered one of six possible global climate models and the carbon emissions scenario – the emissions scenario considered most likely by the International Panel on Climate Change.
Selecting a different global climate model would produce different results, which will be examined in the next phase of the project.
The scenarios evaluated the influence of:
- Two possible rates of population growth: the expected rate vs. a high rate
- Two possible agricultural conditions: the current amount of land under cultivation vs. a larger area that included all reasonably irrigable land, and
- Two possible trends in water use efficiency: current trends vs. the Provincial guideline of achieving 33% efficiency improvements by 2020
Finally, one of the scenarios simulated the effects of a three-year drought, similar to the historically significant Okanagan drought of 1929-1931.
None of the scenarios are a specific prediction of the future, as it is impossible to predict weather conditions year-to-year.
Funding is now in place to conduct additional scenario modeling and study other possible water futures. Running a range of scenarios will give a wider range of water futures and allow a more accurate estimate of risks.
- Summary Report – Part Four – Scenarios (555Kb PDF)