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

Stewart CohenAdaptation & Impacts Research Division (AIRD)Environment Canada, Dept. of Forest Resources Management, UBC

Presented at Canadian Columbia River Forum, October 27-28, 2008.

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 optionsGroup-based modelling

Results from OSWRM

Looking ahead

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

Supply depends on storage in • upland reservoirs• mainstem lakes• ground water (limited)

Okanagan Basin – snowmelt watershed with semi-arid climate

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)

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

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

The 2003 Okanagan drought & fireResponding to future climate change & population growth?

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

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.

Study team (2002-04) & invited guests at team meeting, Summerland, June 2002

Vaseaux Ck (above Dutton Ck) - CGCM2 A2

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Vaseaux Ck (above Dutton Ck) - CGCM2 B2

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Vaseaux Ck (above Dutton Ck) - CSIRO A2

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Vaseaux Ck (above Dutton Ck) - CSIRO B2

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Vaseaux Ck (above Dutton Ck) - HADLEY A2

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Vaseaux Ck (above Dutton Ck) - HADLEY B2

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base90 s20hb2 s50hb2 s80hb2 Str

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Trout Creek supply/demand CGCM2-B2

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Annual flow (m3 x 106)

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Trout Creek supply/demand HadCM3-A2

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Annual flow (m3 x 106)

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Local defined drought – 30% average annual flow

Risks associated with water supply and demand in response to climate change (Neilsen et al., 2004)

Maximum allowable demand – 2002 use

Domestic Demand Side Management Oliver, CGCM2 A2, Medium Population Growth

(Neale et al, 2007)

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Education

Metering CUC

Metering IBR

XeriscapingHigh Eff Retrofit

Combined

• 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

Impact on Okanagan Water Management

Moving Beyond The Damage Report

an opportunity for participatory integrated assessment (PIA) & decision support….

+ =

Decision SupportModel

Technical Info & Data

Experience Based

Knowledge &Values

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

Okanagan

Surfacewater Supply

Precipitating on Lakes

Tributaries Inflowing Evaporating

Flowing Out of Basin

Human Use

DivertingAgricultural Demand

Residential Demand

C & I DemandU.S. Border

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

Upland agriculture supply / demand balance, high population growth;

1 = 1961-1990 base case;

2 = 2040-2069 : HadCM3-A2

NOTE: Supply Demand Balance = (supply – demand) / demand

Uplands residential indoor supply / demand balance, high population growth, no climate change

1 = 1961-1990 base case;

2 = 2010-2039 3 = 2040-2069 4 = 2040-2069

with HadCM3-A2

2040-2069 : Upland agriculture supply / demand balance, high population growth,

1 = HadCM3-A2; 2 = HadCM3-A2

with DSM and densification

Okanagan Inflows vs. Water Demands, HadCM3-A2 (source: Langsdale et al., 2006; in Cohen and Neale 2006)

30-Year Aggregated Supply-Demand Scenarios

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Historic 2020's 2050's

Simulation Period

Flo

w [

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Total Inflow

Total Demand (Ag + Res + Instream)

Total Demand with Residential Adaptation

Dry-Year Aggregated Supply-Demand Scenarios

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Historic 2020's 2050's

Simulation Period

Flo

w [

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Total Inflow

Total Demand (Ag + Res + Instream)

Total Demand with Residential Adaptation

AVERAGE YEAR

DRY YEAR

Note: assumes no change in instream demands to support ecosystems, and reduction in agricultural demand in dry years

2040-2069 : Upland agriculture supply / demand balance, high population growth;

1 = HadCM3-A2 2 = HadCM3-A2

with unlimited supplemental use of Okanagan Lake

NOTE: Assumes withdrawals from lake is unlimited

Okanagan Lake stage, high population growth, no climate change

1 = 1961-1990 base case;

2 = 2010-2039 3 = 2040-2069 4 = 2040-2069,

with HadCM3-A2

2040-2069 : Okanagan Lake stage, high population growth, unlimited supplement with Okanagan Lake, no DSM, max agr.-res. allocations, min conservation flows

1 = no climate change

2 = HadCM3-A2 3 = CGCM2-B2 4 = CSIROMk2-B2

NOTE: Assumes withdrawals not limited by shortages otherwise apparent when relying on tributaries

2040-2069 : Uplands instream allocation deficit, high population growth,

1 = HadCM3-A2 2 = HadCM3-A2

plus unlimited supplement with Okanagan Lake

2040-2069 : Upland agriculture supply / demand balance, high population growth;

1 = 1961-1990 base case;

2 = HadCM3-A2 3 = HadCM3-A2

with DSM and densification

4 = HadCM3-A2 with DSM and Okanagan Lake

5 = Hadley A2 with unlimited use of Okanagan Lake only

2040-2069 : Okanagan Lake stage, high population growth;

1 = 1961-1990 base case;

2 = HadCM3-A2 3 = HadCM3-A2

with DSM (includes densification)

4 = HadCM3-A2 with DSM and Okanagan Lake

5 = HadCM3-A2 with Okanagan Lake only

Okanagan adaptation costs, based on recent & proposed water projects (source: McNeill & Hrasko, 2006)

# PROJECTS ( Listed by $ / ML ) ComponentAnnual ML Developed TOTAL COST $ / ML

8 City of Penticton - Okanagan Lake Intake Pipe Mainstem 8300 947,381$ 114$

13 Glenmore-Ellison Improvement District - Airport Well No. 2 GW 1250 258,060$ 206$

9 District of Salmon Arm - Canoe Lake Intake Pipe Mainstem 3000 755,798$ 252$

14 City of Kelowna - UV Disinfection WT 12775 3,780,000$ 296$

3 Black Mountain Irrigation District - Mission Lake Reservoir (proposed) Watershed 1850 773,548$ 418$

15 Black Mountain Irrigation District - WTP Clarification Only WT 12775 5,541,618$ 434$

10a South East Kelowna Irrigation District - Irrigation Metering Program Conserv. 2925 1,318,362$ 451$

11 Black Mountain Irrigation District - Irrigation Metering Program (proposed) Conserv. 1760 1,050,155$ 597$

2 South East Kelowna Irrigation District - Turtle Lake Expansion (proposed) Watershed 2096 1,944,000$ 927$

1b Lakeview Irrigation District - 1993 Big Horn Dam (to full pool in 1993) Watershed 3400 3,141,882$ 924$

7 Glenmore-Ellison Improvement District - Okanagan Lake Supply (proposed) Mainstem 6400 6,268,388$ 979$

1a Lakeview Irrigation District - 1993 Big Horn Dam (existing) Watershed 2295 2,356,412$ 1,027$

6 District of Summerland - Trout Creek Pump Station ( proposed) Mainstem 3494 4,802,816$ 1,375$

1c Lakeview Irrigation District - 2005 Big Horn Dam expansion Watershed 1105 1,643,532$ 1,487$

12 City of Kelowna - Domestic Metering Program Conserv. 2900 5,822,097$ 2,008$

5 Lakeview Irrigation District - Lambly Creek Dam ( proposed ) moderate 8100 17,743,839$ 2,191$

10b South East Kelowna Irrigation District - Domestic Metering ( proposed ) Conserv. 266 665,451$ 2,502$

16 City of Penticton - WTP Conventional Filtration WT 7300 20,389,697$ 2,793$

17 Westbank Irrigation District - Infilter DAF WT 6570 18,600,000$ 2,831$

18 City of Kamloops - Membrane Filtration WT 19467 58,060,800$ 2,983$

19 Lakeview Irrigation District - DAF Filtration WTP (proposed) WT 5475 17,015,806$ 3,108$

20 Lakeview Irrigation District - Actiflo-Filtration WTP (proposed) WT 5475 18,006,311$ 3,289$

21 Lakeview Irrigation District - Conventional WTP (proposed) WT 5475 18,173,030$ 3,319$

4 Black Mountain Irrigation District - Black Mountain Reservoir (proposed) Watershed 4600 22,944,641$ 4,988$

22 Lakeview Irrigation District - Membrane Filtration WTP (proposed) WT 5475 30,966,849$ 5,656$

GW = groundwater

Watershed = supply expansion

WT = water treatment

Conserv. = manage demand

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 aloneYears 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 regionCould 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

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.