15
Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer www.pacinst.org April 2, 2004 Presentation at the 4 th Annual North Bay Water Conference

Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer April 2, 2004 Presentation

Embed Size (px)

Citation preview

Page 1: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

Conservation Potential and California’s Urban Water Demand

Gary Wolff, P.E., Ph.D.

Principal Economist & Engineer

www.pacinst.org

April 2, 2004

Presentation at the

4th Annual North Bay Water Conference

Page 2: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

Can We Grow The CA Economy Without More Water?

Yes. We’ve Done This For the Last 30 Years Can Continue If More Efficiency Is Possible Our Efficiency Potential Is STILL Large Our Efficiency Potential is Cost-Effective The Limiting Resource Is NOT WATER: It

is Our Ability to See the Big Picture and to Overcome Implementation Obstacles

Page 3: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

Gleick 2001

The link between water use and economic growth can be broken

0

1000

2000

3000

4000

5000

6000

7000

8000

1900 1910 1920 1930 1940 1950 1960 1970 1980 1990 2000

$199

6 U

.S. G

NP

0

100

200

300

400

500

600

700

800

900

1000

Wat

er W

ithdr

awal

s (k

m3/

yr)

Page 4: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

California Water Withdrawals and Economic Output Trends

$0

$100,000

$200,000

$300,000

$400,000

$500,000

$600,000

$700,000

$800,000

$900,000

0

10,000

20,000

30,000

40,000

50,000

60,000

70,000

80,000

90,000

Gross State Product (Millions of 1992 $)

Water Withdrawals (MGD)

Page 5: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

But Can We Continue To Grow Without Additional Physical Water?

No Comprehensive Statewide Estimate of the Potential for Urban Water Conservation Had Ever Been Done.

Such An Analysis – Done Right – Must Use An “End-Use” Approach.

Important Data Gaps Remain to be Filled

Page 6: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

The Pacific Institute Report -- “Waste Not, Want Not: …”

Three-Year Process

Extensive Independent Reviews

Report Released in November 2003

Report and Appendices Available Online: www.pacinst.org/reports/urban_usage

Funded by DWR/CalFed; and the Hewlett, Environment Now, & MacArthur Foundations

Page 7: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

California Urban Water Use – 2000 (6.9 million acre-feet per year)

Unaccounted for Water 10%

Industrial10%

Residential Indoor32%

Residential Outdoor

21%

Commercial27%

Page 8: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

CII Sectors by Group

COMMERCIAL/ INSTITUTIONAL

Educational (K-12, Colleges, Special Education)

HotelsRestaurantsFood and Beverage StoresOther Retail StoresOffice BuildingsHospitalsGolf CoursesCoin LaundriesIndustrial Laundries

INDUSTRIAL

Food ProcessingDairyMeat ProcessingFruit and Vegetable Proc.BeveragesPetroleum RefiningHigh TechnologyPaper - Paperboard MillsTextilesFabricated Metals

Page 9: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

How We Evaluated CII Potential

0 50 100 150 200 250 300 350 400

Restaurants

Office Buildings

High Tech

TAF per Year

Restroom Cooling Landscaping Laundry Kitchen Process Other

Page 10: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

Indoor Residential Water Use – 2000

(2.3 MAF/yr)End Use Acre-feet per year

Toilets 734,000

Showers 496,000

Faucets 423,000

Clothes Washers 330,000

Leaks 285,000

Dishwashers 28,000

Total 2,296,000

Page 11: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

End-Use Analysis: Clothes Washers WU(t) = HH(t) x L/D x G/L = WU(t)

– WU (t) = Total Water Use at Time “t”

– HH (t) = Households at Time “t”

– L/D = Loads per HH per Day

– G/L = Gallons per Load

Compare WU(t) When G/L Changes, Holding Size of Loads Constant

Estimate of Conservation Potential Based on Comparing Average G/L Now With Average G/L of “Efficient” Machines

Page 12: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

Some Economic Results – Residential Indoor Conservation

-1200

-700

-200

300

800

ULFT Retroft Low-FlowShowerheads

EfficientDishwashers

EfficentClotheswashers

Cos

t of

Con

serv

ed W

ater

($/

AF

)

Natural Replacement Accelerated Replacement

Page 13: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

Haasz et al. 2002

Indoor Residential Conservation Potential Over Time

0

1,000

2,000

3,000

4,000

5,000

6,000

1980 1985 1990 1995 2000 2005 2010 2015 2020

Mill

ion

Cub

ic M

eter

s p

er Y

ear

No Efficiency Improvements

Current Use

Cost-Effective Efficiency *

Page 14: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

Total Urban CA Efficiency Potential

Sector Urban Water Use, 2000 (TAF/Yr)

Efficiency Potential

Cost-Effective Potential

Res-Indoor 2,300 893 893

Res-Outdoor 983 – 1,900 360 to 580 470

Comm/Inst. 1,850 714 658

Industrial 665 260 Incl. in C/I

Unaccounted

695 Not Eval. Not Eval.

Total 6,960 (+/- 10%) 2,337 2,020

Page 15: Conservation Potential and California’s Urban Water Demand Gary Wolff, P.E., Ph.D. Principal Economist & Engineer  April 2, 2004 Presentation

Conclusions: Growth in Water Demand Is Not Inevitable Future Demand Need Not Grow Because

Additional Improvements in Water Use Efficiency Are Possible and Economical

But Implementing Change Requires:– Partnerships Across Traditional Boundaries

(e.g., Water/ Wastewater/ Stormwater/ Energy)– Capturing the “Other Benefits” We Identified– Better Balance of New (e.g. Customer Behavior)

and Old (e.g., Hydrologic) Uncertainties