Document

www.waterdm.com

www.incentware.com

Urban Water Demand Trends

Conservation and the Future of Residential

Water UsePeter Mayer, [email protected]

www.a4we.org

Water Demand Management: Why?

• Water shortages• Expensive to develop new

supplies• Climate change

Demand Management = Serious Business

Drought @2050 vs Notorious Recent Historical Droughts

2040-2060

PDSI = Palmer Drought Severity Index

PDSI was developed by Wayne Palmer in the 1960s and uses temperature and rainfall information in a formula to determine dryness.

Source: Dr. Martin Hoerling, NOAA Earth System Research Laboratory

Greeley Colorado Historic Demand

0.000

2,000.000

4,000.000

6,000.000

8,000.000

10,000.000

12,000.000

1908

1913

1918

1923

1928

1933

1938

1943

1948

1953

1958

1963

1968

1973

1978

1983

1988

1993

1998

2003

2008

2013

City of Greeley Water Production (MGD)

Utilities are Asking: Where did the demand go?

In 2008 a typical household used ~ 12,000 gallons less than in 1978 (Coomes, P. et. al. 2010).

Significant demand reductions were observed prior to recession.

0

20

40

60

80

100

120

140

160

2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010

Aver

age

Annu

al P

er H

ouse

hold

Use

(kga

l)Avg. Per Household Use = 112.5 kgal/yearStandard Deviation = 11.4 kgal/year

City of Westminster, CO average annual household water use, 2000 – 2010, with trend line

Seattle Public Utilities - 1990

0

25

50

75

100

125

150

175

200

225

250

1930 1940 1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050 2060 2070

Ann

ual A

vera

ge M

GD

Actual Demand

Forecast Without Conservation

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25

50

75

100

125

150

175

200

225

250

1930 1940 1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050 2060 2070

Ann

ual A

vera

ge M

GD

Actual Demand

Forecast WithoutConservation

Firm Yield in 2013

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25

50

75

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250

1930 1940 1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050 2060 2070

Ann

ual A

vera

ge M

GD

Actual Demand

Current Firm Yield

Forecast WithoutConservation

Forecast With Conservation

0

25

50

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1930 1940 1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050 2060 2070

Ann

ual A

vera

ge M

GD

Actual Demand

Current Firm Yield

Forecast WithConservation

Forecast WithoutConservation

70+ Years

2013

0

25

50

75

100

125

150

175

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250

1930 1940 1950 1960 1970 1980 1990 2000 2010 2020 2030 2040 2050 2060 2070

Ann

ual A

vera

ge M

GD

Actual Demand

Current Firm Yield

Forecast WithConservation

Forecast WithoutConservation

New Supply

70+ Years

A brief history of demand forecasting in Seattle

Seattle Saved $725 millionPV Cost of New Supply $800

MillionPV Cost of Conservation: $ 75

Million_______________________________________________________________

NPV : $725 Million

Avg. Annual Use Per SF Home (kgal)

Source: Mayer, P. et. al. 2013. Residential End Uses of Water Update. AWWA - ACE, Denver, CO.

1999 REUWS vs. 2014 REUWSgallons per household per day

2014 REUWS Update

62.256.2 53.9

47.2 45.7 44.8 44.4 44.5 44.2 44.0 43.6 39.0 35.6

Gal.

per c

apita

per

day

(gpc

d)

Indoor Gallons Per Capita Per DayNormalized for Household of 3

Homes Meeting Efficiency CriteriaToilet < 2 gal., Clothes washer <30 gal.

100%

41% 47% 43% 45% 48%

15%

100%

24%41% 48% 52% 56%

15%

0%

20%

40%

60%

80%

100%

120%

Perc

ent M

eetin

g Effi

cien

cy C

riter

ia

% Efficient Toilets % Efficient CWs

How much more conservation?

• A lot.• We’re almost…half way there!• New technology• Outdoor efficiency• WaterSense• Leak detection• Advanced metering• Conservation-oriented rates• Customer engagement through data and information

Future Trends• Technological change• Behavioral change• More intense and frequent drought• Water demand management at the

retail level

Thank You

Peter Mayer, [email protected]