Moving Beyond the Damage Report: Adapting to Climate Change in the Okanagan Region

1. Moving Beyond the Damage Report:Adapting to Climate Change in the Okanagan Region Stewart Cohen Adaptation & Impacts Research Division (AIRD) Environment Canada, Dept. of Forest Resources Management, UBC Presented at Canadian Columbia River Forum, October 27-28, 2008.

2. Today’s discussion—Okanagan water resources and climate change • The climate change “damage report” • Water supply • Agricultural and residential water demand • Change in risk • Assessment of adaptation options • Group-based modelling • Results from OSWRM • Looking ahead

3. Okanagan region, British Columbia, is part of the Columbia Basin Okanagan Basin CANADA ------------ U.S.A. Source: Cohen and Kulkarni (2001); left panel from Alan Hamlet (U. Washington) Zosel Dam

4. Okanagan Basin – snowmelt watershed with semi-arid climate • Supply depends on storage in • upland reservoirs • mainstem lakes • ground water (limited) Photos: upper left—Kelowna and Okanagan Lake, lower left--Osoyoos and Osoyoos Lake (Denise Neilsen); right—installation of intake at Penticton, Okanagan Lake (Bob Hrasko)

5. Water Resources in the Okanagan Basin • Area = 8200 km2 • Okanagan Valley = 160 km in length • Population: 2006 = 340,000 [2001 = 300,000] • Governance; 13 municipalities, 3 regional districts, 4 First Nation communities, 59 “improvement districts” • Agriculture: fruit, vineyards, pasture; 40% irrigated lands

6. Agricultural land use in the Okanagan Basin (photos from Denise Neilsen)

7. The 2003 Okanagan drought & fire Responding to future climate change & population growth?

8. Okanagan Study Teams (1999-2007) • Stewart Cohen (P.I.) – Adaptation & Impacts Research Division-EC, Institute for Resources Environment & Sustainability-UBC, Vancouver • Denise Neilsen (P.I.2002-04), Scott Smith (P.I.2002-04), Grace Frank, Walter Koch – Pacific Agricultural Research Centre-AAFC, Summerland • Younes Alila, Wendy Merritt* – Forest Resources Management, UBC (*now at Australian National University) • Mark Barton, Roger McNeill, Bill Taylor, Dave Hutchinson, Wendy Avis – Pacific & Yukon Region-EC • Tina Neale, Philippa Shepherd, James Tansey, Jeff Carmichael, Stacy Langsdale, Rachel Welbourn, Natasha Schorb, Jennifer Ardiel, Glen Hearns, Alex Russell, Aviva Savelson, Sharon Bennett, Charlie Wilson – IRES & SCARP, UBC • Brian Symonds, B.C. MOE, Penticton • Bob Hrasko, Agua Consulting, Kelowna. • Barbara Lence, Civil Engineering, UBC • Craig Forster, U. Utah • Allyson Beall, Washington State University Study team (2002-04) & invited guests at team meeting, Summerland, June 2002 Thanks to Andrew Reeder, RDOS (formerly City of Summerland); Toby Pike, Water Supply Association; Greg Armour, OBWB; Patrick Deakin, Town of Oliver; Phil Epp, BC MOE; Jillian Tamblyn, Okanagan Nations Alliance; Leah Hartley, RDCO; Peter Waterman, BC Fruit Growers Assoc. & City of Summerland; & many others. Supported by grants from the CCAF/CCIAP (#A206, A463/433, A846), Natural Resources Canada, Ottawa.

9. Streamflow Scenarios for Vaseux Creek (Merritt et al., 2006)

10. Risks associated with water supply and demand in response to climate change (Neilsen et al., 2004) Maximum allowable demand – 2002 use Local defined drought – 30% average annual flow

11. Domestic Demand Side Management Oliver, CGCM2 A2, Medium Population Growth (Neale et al, 2007) 8000 7000 6000 2001 Baseline Current DSM 5000 Education Metering CUC 4000 Water Demand (ML) Metering IBR Xeriscaping 3000 High Eff Retrofit Combined 2000 1000 0 2069 2001 2005 2009 2013 2017 2021 2025 2029 2033 2037 2041 2045 2049 2053 2057 2061 2065 Year

12. Impact on Okanagan Water Management • Incorporation of climate change into Trepanier Landscape Unit Water Management Plan • Recommends demand management as first priority, along with supply augmentation, by 2050 if no climate change assumed, and by 2020 if climate change is assumed

13. Moving Beyond The Damage Reportan opportunity for participatory integrated assessment (PIA) & decision support…. + = Experience Based Knowledge & Values Technical Info & Data Decision Support Model

14. Preliminary sketch of decision model(Langsdale et al., 2006, 2007)

15. Input from some participants at Okanagan study model building workshop, April 2005 (Cohen & Neale, 2007)

16. Upland agriculture supply / demand balance, high population growth; • = 1961-1990 base case; • = 2040-2069 :HadCM3-A2 NOTE: Supply Demand Balance = (supply – demand) / demand

17. Uplands residential indoor supply / demand balance, high population growth, no climate change • = 1961-1990 base case; • = 2010-2039 • = 2040-2069 • = 2040-2069 with HadCM3-A2

18. 2040-2069 : Upland agriculture supply / demand balance, high population growth, • = HadCM3-A2; • = HadCM3-A2 with DSM and densification

19. AVERAGE YEAR Okanagan Inflows vs. Water Demands, HadCM3-A2 (source: Langsdale et al., 2006; in Cohen and Neale 2006) DRY YEAR Note: assumes no change in instream demands to support ecosystems, and reduction in agricultural demand in dry years

20. 2040-2069 : Upland agriculture supply / demand balance, high population growth; • = HadCM3-A2 • = HadCM3-A2 with unlimited supplemental use of Okanagan Lake NOTE: Assumes withdrawals from lake is unlimited

21. Okanagan Lake stage, high population growth, no climate change • = 1961-1990 base case; • = 2010-2039 • = 2040-2069 • = 2040-2069, with HadCM3-A2

22. 2040-2069 : Okanagan Lake stage, high population growth, unlimited supplement with Okanagan Lake, no DSM, max agr.-res. allocations, min conservation flows • = no climate change • = HadCM3-A2 • = CGCM2-B2 • = CSIROMk2-B2 NOTE: Assumes withdrawals not limited by shortages otherwise apparent when relying on tributaries

23. 2040-2069 : Uplands instream allocation deficit, high population growth, • = HadCM3-A2 • = HadCM3-A2 plus unlimited supplement with Okanagan Lake

24. 2040-2069 : Upland agriculture supply / demand balance, high population growth; • = 1961-1990 base case; • = HadCM3-A2 • = HadCM3-A2 with DSM and densification • = HadCM3-A2 with DSM and Okanagan Lake • = Hadley A2 with unlimited use of Okanagan Lake only

25. 2040-2069 : Okanagan Lake stage, high population growth; • = 1961-1990 base case; • = HadCM3-A2 • = HadCM3-A2 with DSM (includes densification) • = HadCM3-A2 with DSM and Okanagan Lake • = HadCM3-A2 with Okanagan Lake only

26. Okanagan adaptation costs, based on recent & proposed water projects (source: McNeill & Hrasko, 2006) GW = groundwater Watershed = supply expansion WT = water treatment Conserv. = manage demand

27. Conclusions and Looking Ahead • In the Okanagan, climate change will result in reduced water supply, increased water demand, and a regional water deficit that would increase over time • These effects are greater than what would be projected from population growth alone • Years with water supply shortages would occur more frequently • DSM combined with supplemental use of valley bottom lakes would offer the region a viable adaptation portfolio, but this would be challenging to manage within the regional context of rapid population growth • There needs to be more explicit inclusion of climate change adaptation in long term sustainable development planning for the Okanagan and the larger Columbia Basin • Participatory integration offers an important opportunity for shared learning and ownership of research outcomes, so that global climate science and local water policy can be more easily linked • Can link to research and planning initiatives originating from within the region • Could inform future model development and improvement (e.g. OSWRM—land use change, groundwater, managing instream allocations) • Can link to ongoing planning related to balancing watershed management objectives

28. For more information on Okanagan studies… • scohen@forestry.ubc.ca; stewart.cohen@ec.gc.ca • slangsdale@gmail.com • http://www.forestry.ubc.ca/aird [navigate to Projects Completed; project report listed as Cohen and Neale, 2006; additional papers by Langsdale et al., 2007 -- The Integrated Assessment Journal, and Langsdale et al. in review; OSWRM available for download] This project was made possible by financial support from the Government of Canada’s Climate Change Impacts and Adaptation Program, Projects A206, A463/433, and A846, and by in-kind support from federal, provincial and local government agencies, non-government organizations, and the University of British Columbia. We thank Craig Forster, Allyson Beall, and Jeff Carmichael for assistance with model construction.