[PPT] - THE FINANCIAL BENEFITS OF WATER CONSERVATION: THE TUCSON STORY MARY PowerPoint Presentation

SLIDE 1

THE FINANCIAL BENEFITS OF WATER CONSERVATION: THE TUCSON STORY

CANDICE RUPPRECHT WATER CONSERVATION MANAGER TUCSON WATER

PETER MAYER, P.E.

PRINCIPAL WaterDM

MARY ALLEN, P.E. BUSINESS PROCESS IMPROVEMENT PIMA COUNTY REGIONAL WASTEWATER RECLAMATION

SLIDE 2

AWE AVOIDED COST STUDY

Alliance for Water Efficiency grant funds from Walton

Family Foundation focused on Colorado River Basin Initiative

WaterDM and City of Westminster Study
Tucson, AZ and Gilbert, AZ selected to participate
Goal of the study is to examine the impact of increased

water use efficiency on customer rates

SLIDE 3

WATER USE IN THE US, 1900 - 2010

Includes fresh and saline

water. Source USGS and

Pacific Institute 2015

SLIDE 4

M&I WATER USE IN THE US, 1900 - 2010

Source USGS and Pacific Institute 2015

SLIDE 5

TUCSON WATER ANNUAL PRODUCTION (1940-2016)

CAP Production Potable Production TARP Production Reclaimed Production

20,000 40,000 60,000 80,000 100,000 120,000 140,000

Water Production for TW Service Area (Acre-Feet)

1940 1950 1960 1970 1980 1990 2000 2010

Year

2016 2016

CAP Reclaimed Water TARP Total Potable Water Use at 1985 Level

SLIDE 6

RESIDENTIAL INDOOR GPCD

69.3 58.6 36.7

0.0 10.0 20.0 30.0 40.0 50.0 60.0 70.0 80.0 REU1999 REU2015 High-Efficiency (Aquacraft 2011d) Indoor Average Gallons Per Capita Per Day (gpcd)

Source: Water Research Foundation (2016) Residential End Uses of Water Update – #4309. Denver, CO.

1999 vs. 2016 = 15.4% reduction 2016 vs. HE = 37.4% reduction

SLIDE 7

INDOOR GPCD COMPARISON

Toilet Clothes washer Shower Faucet Leak Other Bath Dishwasher REU1999 18.5 15.0 11.6 10.9 9.5 1.6 1.2 1.0 REU2015 14.2 9.6 11.1 11.1 7.9 2.5 1.5 0.7

2 4 6 8 10 12 14 16 18 20

Gallons per capita per day (gpcd) Source: Water Research Foundation (2015) Residential End Uses of Water Update – #4309. Denver, CO.

Statistically significant reductions in:

Clothes washer
Toilet
Dishwasher

SLIDE 8

WATER EFFICIENCY IS NOT ONE, BUT MANY APPROACHES

Utility-sponsored conservation & education programs
Rebates, Youth & Professional Education
Community outreach campaigns: Pete the Beak; Water Reliability
Increasing block rate structures
4-Tier structure: $1.55,1-7 ccf; $3.00, 8-15 ccf; $7.48, 16-30 ccf; $11.75 > 30 ccf
Local ordinances: Xeriscape Landscaping (1991), Water Waste (1984) & Comm.

Rainwater Harvesting (2008)

International Plumbing Code  Tucson Plumbing Code
National Policy that drives Innovation & technology improvements
Energy Star (2002) & WaterSense (2006)

SLIDE 9

20 40 60 80 100 120 140 160 180

1985 1986 1987 1988 1989 1990 1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015

SF Household Avg. Annual Use (CCF)

1960s & 1970s Typical landscape Preferences shift… A typical landscape today

SINGLE FAMILY AVG. ANNUAL USE 1985 - 2015

Present-day Typical landscape

SLIDE 10

20 40 60 80 100 120 140 160 180 200

System GPCD

TOTAL SYSTEM GPCD 1980 - 2015

SLIDE 11

SLIDE 12

188 130 105 78 512,000 717,875

20

40 60 80 100 120 140 160 180 200 1989 2015

100,000

200,000 300,000 400,000 500,000 600,000 700,000 800,000 Gallons per Capita Per Day Population System Per Capita Water Use (gallons/day) System Per Capita Wastewater Use (gallons/day) Service Area Population

POPULATION AND PER CAPITA WATER AND WASTEWATER USE

SLIDE 13

1989: 188 / 107 gpcd

Pop. 512,000

2015: 130 / 79 gpcd

Pop. 717,875

96.4 93.3 134.4 54.0 56.2 80.0 0.0 20.0 40.0 60.0 80.0 100.0 120.0 140.0 160.0 1989 2015 2015 Hypothetical

Avg. Daily Production/Flow (MGD)

Water Wastewater

HYPOTHETICAL, NON-CONSERVING WATER DEMAND

Daily Water Production & Wastewater Flows:

1989 actual
2015 actual
2015 hypothetical

SLIDE 14

“WHY ARE MY RATES GOING UP AGAIN WHEN I KEEP CONSERVING WATER?!”

Due to conservation, per capita water use in Tucson has

dropped 45% and wastewater by 35% since 1989.

Yet…. costs to customers continue to increase.
Some customers are confused and frustrated.
What is the impact on water and wastewater rates

due to conservation?

SLIDE 15

WATER SYSTEM AVOIDED COSTS

Water Treatment Infrastructure
Pumping & transmission expansion
Water Resources
Operating Costs

How Much Additional Cost to Tucson Water meet non- conserving, hypothetical demand of 134 mgd?

SLIDE 16

WASTEWATER SYSTEM AVOIDED COSTS

2015 Avg. Daily Flow ~ 56.2 MGD
Hypothetical Non-Conserving Avg. Daily Flow ~ 80 MGD
Current System Max. Treatment Ability ~ 95 MGD
In this analysis, wastewater treatment capacity water increased

to 107 MGD to meet Hypothetical Non-Conserving Daily Flow range

What additional wastewater system infrastructure and costs to meet 80 mgd avg. daily flow?

SLIDE 17

ADDITIONAL COSTS OF MEETING A NON-CONSERVING DEMAND… THAT HAVE BEEN AVOIDED

Additional $22 million per year for water system O&M
$140,000,000 for new Avra Valley Transmission Main CIP
$15 million for new 7 MGD recycled water facility
Additional $6.4 million per year for wastewater treatment O&M
$195,000,000 for additional 12 MGD of wastewater capacity,

financed over time

SLIDE 18

CUSTOMER RATE IMPACT

Current avg. single-family, water customer uses 98.9 ccf/year, and pays

for 84 ccf/year of wastewater treatment.

At current water rates, the avg. single-family customer pays $847 per year

for water and sewer.

Under the non-conserving scenario (assuming 188 gpcd) the average

single-family customer would pay $976 per year for water and sewer.

Due to water efficiency, rates today are nearly 15.3% LOWER than otherwise necessary.

SLIDE 19

74.0 97.2

63.0 82.8 $847 $976 $- $200 $400 $600 $800 $1,000 $1,200 20 40 60 80 100 120

2015 Actual Non-Conserving Hypothetical Annual Water & Wastewater Bill - $ Annual Water and Wastewater Use (kgal)

Impact to an Average Single-Family Customer - Tucson, AZ

Water Use (kgal) Wastewater Discharge (kgal) Annual Water & Wastewater Bill - $

SLIDE 20

BREAKDOWN OF AVOIDED COSTS

Water Transmission, 11.8% Reclaimed Water, 0.0% Interest and Debt Service, 17.0% Water Treatment Operation, 38.6% Wastewater Treatment, 21.8% Wastewater Treatment Operation, 10.8%

Tucson Water rates are 22.3% lower today and Pima County WR rates are 7.8% lower today than otherwise necessary if per capita water demand had not been reduced.

SLIDE 21

STRENGTH OF SEWER FLOWS

216 429 205 338 22781 20424 18000 18500 19000 19500 20000 20500 21000 21500 22000 22500 23000 23500 50 100 150 200 250 300 350 400 450 500 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016

Flow in Million Gallons/year Average Strength (mg/L)/year

TSS BOD Combined Influent Flows for Agua Nueva and Tres Rios

SLIDE 22

IMPACT TO THE SEWER PIPES

Scour velocities may take longer to attain in

newer developments with lower flows

Flushing of pipes may be required
Potential for more odors in pipes
Potential for corrosion in pipes
Terminal ends may require steeper slopes
Cost goes up for deeper sewers

SLIDE 23

FLUSHING THE PIPES

SLIDE 24

PIPE MAY REQUIRE STEEPER SLOPES

Table 5.1 Minimum Slopes for Gravity Sewer Lines Pipe Diameter (inches) Minimum Slope (ft/ft) *Full-Flow Velocity (ft/sec) 6 (terminal reach) 0.0110 3.0 8 (terminal reach) 0.0100 3.5 8 (non-terminal reach) 0.0044 2.3 10 0.0025 2.0 12 0.0019 2.0 15 0.0014 2.0 18 0.0011 2.0 24 0.0008 2.0

*Manning’s (n) value of 0.013 used

SLIDE 25

ODORS AND CORROSION

SLIDE 26

Bottom Line: When Everyone Conserves, Everyone Saves

Water and wastewater rates have increased because of the increasing

costs of providing 24/365 service, while maintaining and improving infrastructure to meet regulatory treatment requirements.

Decreasing demands are a balancing act: Revenue v. Resources
The typical Tucson single-family customer pays 15% less today,

than they would need to be if water efficiency had not been achieved.

SLIDE 27