Chapter 7. Water Conservation: Cost Effectiveness
Introduction
This chapter focuses on the cost-effectiveness of conservation strategies. The State of
California's Water Conservation Plan of 2009 set a mandate that water districts must reduce their
per capita water consumption 20% by 2020. Further, the 2009 Conservation Plan identifies a set
of water conservation best management practices to achieve this mandate. The best management
practices are based on state wide studies. While the 14 BMPs that the state of California
recommends were evaluated to be cost-efficient on a state-wide level, no measurement of costefficiency was completed on a district by district basis. A BMP that is cost-efficient on a statewide level might not be cost-efficient for a specific water district based on characteristics of the
district: its water supply mix of local and imported sources, the unique cost of implementing a
BMP in a district, and the costs of a district’s planned future water supply addition. The
objectives of the cost-effectiveness study we conducted were to assess if the 14 state
recommended BMPs are cost-efficient for two water districts we studied, to identify which
BMPs provide the most value to each agency in the short and the long term in reducing water
consumption, as well as to determine and compare the differences in the cost-effectiveness of the
strategies among districts.
Methodology for the Cost-Effectiveness Analysis
This report applies a methodology developed by the California Urban Water
Conservation Council to assess which of these conservation measures are the most cost-efficient
in reducing local water districts per capita water use. In this chapter, we present the methodology
and apply it to Los Angeles DWP and to Cucamonga Valley Water District/IEUA. In the analysis,
we focus on water conserving appliances and devices where costs have been quantified.
The cost-efficiency calculations involve a two-step process. First, the marginal cost of
water delivery for the district is calculated. This is the cost to the district of the “last unit” of
water delivered, and is the most expensive unit of water delivered. Finding this marginal cost
gives the district an avoided costs value and is the value to the district of lowering water demand
by one unit.
Second, the cost to the district of each water conservation measure is found by unit of
water demand reduction. Comparing the avoided costs value with conservation measures’ costs
per unit of demand reduction allows the assessment of cost-efficiency. For example, if a district
has an avoided cost value of $100 dollars per unit of reduction then any conservation measure
that cost less than $100 dollars per unit of water savings is considered cost-efficient. The district
will recoup the cost of the measure with its savings from lowered water delivery.
159
One of the most important aspects of this methodology is assessing not only short-run
avoided costs but also long-run avoided costs to the district. Currently, many districts evaluate
the costs and benefits of water conservation measures based on short-run avoided costs only.
This under-values conservation measures because it does not take into account future cost
savings for the districts from deferring or downsizing future water system upgrades because of
lowered water demand.
The cost-efficiency methodology is applied to the Los Angeles Department of Water and
Power (LADWP) in Southern California and the Cucamonga Valley Water District (CVWD). An
excel model developed by the California Urban Water Conservation Council (CUWCC) is used
to estimate the district’s avoided costs values. The inputs for the CUWCC’s model include the
future water demand estimates for LADWP and CUWCC, their water system components and
their variable operating costs, the “on-margin” probabilities of the water system components, and
the planned water system additions. Using these inputs the model forecasts the LADWP’s and
CVWD short-run, long-run, and total avoided costs values of reduced water demand for each
year up to 2035.
The data used for the model’s inputs is drawn from various sources including the
LADWP’s and the CVWP’s Urban Water Management Plans (UWMP), annual budgets, and
reports to other agencies. Because there was no direct access to the districts’ internal planning
documents, some of the model’s input values needed to be estimated. When this occurred, the
most conservative values possible were used to ensure the model’s output does not lead to an
overestimation of the value of conservation measures to the district.
An important note for the model is the difference between average costs and marginal
costs. The CUWCC model’s avoided costs estimates represent the marginal costs of supplying
water. Taking all the district’s costs and dividing by its total water delivered would give the
district’s average costs. This would not give an accurate value of avoided costs because many
costs are fixed costs—they are incurred whether or not demand is decreased. For this reason the
CUWCC’s model calculates the marginal costs of water delivery, or the costs of delivering the
last unit of water to the district’s customers.
The Cost-Effectiveness of LADWP’s Best Management Practices
The analysis of LADWP’s BMPs is organized into four sections. First, the spreadsheets
within the CUWCC’s model are presented and discussed. The inputs and outputs are described as
well as the sources and justifications for input values. Next, the report provides information on
the costs of LADWP’s water conservation measures. Additionally, the cost-efficiency
methodology is applied to compare the conservation measures’ costs and benefits in specific time
periods and benefit-cost ratios are calculated.
Common Assumptions
The CUWCC model’s first spreadsheet (Figure 7.1) requires inputs on common
assumptions about the LADWP:
160
Figure 7.1 Common Assumptions Spreadsheet, CUWCC Model
Source: CUWCC (2006) Spreadsheet Model
Analysis Start Year: 2010 is the starting period.
Planning Horizon: The model requires the district’s estimates of future water demand from its
UWMP. The most recent 2010 LADWP UWMP’s future demand estimates end in 2035 limiting
the model’s timeline (2010 UWMP).
Cost Reference Year: The model’s default value is 2005.Updating the cost reference year to 2010
dollars increases the relevance of monetary estimates.
Lost and Unaccounted for Water: This input value is derived from the district’s 2010 UWMP
which provides information on “Water Demand Forecast” for the district. In 2010 the district’s
“Non-Revenue Demand” was estimated to be 33,515 AF per year. The district defines nonrevenue water as system loss. The total water use in 2010 is estimated to be 554,556 AF.
Dividing the 33,515 AF loss by the 554,556 AF total water demand gives a value of .0604 which
rounds to 6 percent—the estimated water loss percent for the district (2010 UWMP).
Peak-Season Start and End Date: Determining the peak-season is important for calculating the
district’s marginal costs. In the peak season water demand is significantly higher than in the offpeak season. Conservation programs that lower peak-season demand, such as water conservation
landscaping, will have a higher avoided cost value associated with their water savings. The
district's peak season is estimated to begin on June 1st and end on October 30th, based on its
monthly average water use.
161
Projected Interest Rate: The projected interest rate allows the CUWCC’s model to estimate the
future cost savings from downsized or deferred water system component additions—capital
projects that require district borrowing. The model’s default value of 6% is used for LAWDP.
Inflation Rate: The model’s default value of 2% inflation per year was used.
Units of Measure: LADWP reports it’s measurements in U.S. units (Figure 7.2). The system
volume is in acre-feet (AF) because LADWP reports its water demand and supply data in AF.
Figure 7.2 : Units of Measure for Model
Forecasted Demands: The model’s next input spreadsheet requires projections of future water
demand from the district’s 2010 UWMP, which gives the district’s demand estimates in five
years intervals. Because the LADWP’s model requires estimates for each year, using the five
year UWMP estimates the values for each year are interpolated. The district’s interpolated water
demand projections are displayed in Table 7.1.
Table 7.1 Future Water Demand Projections (2010 UWMP)
Year
Total Demand in AF
Year
Total Demand in AF
2010
554,556.0
2023
666,167.2
2011
566,603.6
2024
670,885.6
2012
578,651.2
2025
675,604.0
2013
590,698.8
2026
680,716.0
2014
602,746.4
2027
685,828.0
2015
614,794.0
2028
690,940.0
2016
622,237.6
2029
696,052.0
2017
629,681.2
2030
701,164.0
2018
637,124.8
2031
703,083.2
2019
644,568.4
2032
705,002.4
2020
652,012.0
2033
706,921.6
2021
656,730.4
2034
708,840.8
2022
661,448.8
2035
710,760.0
The model’s spreadsheet for “Forecasted Demands” is displayed in Figure 7.3. The first
column of the spreadsheet displays the future year. The next two columns require data on future
162
peak and off-peak demand projections. The next three columns display model outputs on annual
demand growth and deferral periods.
Figure 7.3 Forecasted Demands Spreadsheet
Forecasted Demands
Demand Data Entry Units:
Flow
Seasonal Demand
Peak
Off-Peak
Year
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
(mgd)
267326.3786
273133.982
278941.5853
284749.1887
290556.792
296364.3953
299952.6184
303540.8415
307129.0645
310717.2876
314305.5107
316580.038
318854.5654
321129.0927
323403.6201
325678.1474
328142.4115
330606.6756
333070.9397
335535.2038
337999.4679
338924.6275
339849.7871
340774.9466
341700.1062
342625.2658
(mgd)
286667.4687
292895.2527
299123.0368
305350.8208
311578.6048
317806.3888
321654.2202
325502.0516
329349.8829
333197.7143
337045.5456
339484.6353
341923.7249
344362.8145
346801.9041
349240.9938
351883.5476
354526.1015
357168.6553
359811.2092
362453.7631
363445.858
364437.953
365430.0479
366422.1429
367414.2378
Annual Demand Growth
Peak-Season Off-Peak Season
(mgd)
(mgd)
Peak Season
1 mgd
Deferral Periods
(years)
5807.6
6227.8
0.000
5807.6
6227.8
0.000
5807.6
6227.8
0.000
5807.6
6227.8
0.000
5807.6
6227.8
0.000
3588.2
3847.8
0.000
3588.2
3847.8
0.000
3588.2
3847.8
0.000
3588.2
3847.8
0.000
3588.2
3847.8
0.000
2274.5
2439.1
0.000
2274.5
2439.1
0.000
2274.5
2439.1
0.000
2274.5
2439.1
0.000
2274.5
2439.1
0.000
2464.3
2642.6
0.000
2464.3
2642.6
0.000
2464.3
2642.6
0.000
2464.3
2642.6
0.000
2464.3
2642.6
0.000
925.2
992.1
0.001
925.2
992.1
0.001
925.2
992.1
0.001
925.2
992.1
0.001
925.2
992.1
0.001
925.2
992.1
0.001
The model requires total demand to be split between peak and off-peak seasonal use
(column 2 and 4).To split the data one needs to calculate peak and off-peak multiplier factors
derived from monthly water use data. The LADWP has provided monthly water use data from
2001 to present. The calculated monthly averages are shown in Table 7.2.
Figure 7.4 displays the average monthly water use graphically. The red dashed lines
outline the peak period for the district from June 1st to October 30th.As the graph demonstrates,
average water use is significantly higher during the peak period. Table 7.3 displays the peak and
off-peak averages as well as the yearly average water use. To find the peak factor, the peak
average of 56045.48 is divided by the yearly average of 43732.23 which gives a peak factor of
1.15. The same method is used to find the off-peak factor of 0.89.
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Table 7. 2 Monthly AF Average LADWP Water Use
Month
Average Water Use in AF
January
February
March
April
May
June
July
August
September
October
November
December
45,132.00
39,688.56
39,592.63
41,034.49
45,402.98
51,730.16
55,867.58
57,841.29
58,945.47
55,847.91
50,142.77
45,132.16
Figure 7.4 Monthly Average Water Use
Table 7.3 Peak and Off-Peak Factors
Peak Average June - October
Peak Factor
56046.48
1.15
Off-Peak Average November –
May
Off-Peak Factor
43732.23
0.89
Yearly Average
48863.17
164
Given the peak and off-peak factors, the following steps are taken to find the peak and
off-peak demand values which are inputted into the “forecasted demand” spreadsheet (Table
7.4):

Divide yearly demand by 365 to find the average daily demand (column 2)

Calculate number of peak and off-peak days in a year (153 and 212)

To calculate total peak water demand per year, average daily demand is
multiplied by days of peak demand and then multiply by the peak factor (column 3)

To calculate total off-peak water demand per year, average daily use is multiplied
by days of off-peak demand and then multiply by off-peak factor (column 4)
Table7. 4 Peak and off -peak yearly water demand calculations
Year
Average Daily
Peak Demand
Off-Peak
Demand
2010
1,519.33
267,326.4
286,667.5 Days-Peak
2011
1,552.34
273,134.0
292,895.3 Days Off-Peak
2012
1,585.35
278,941.6
299,123.0 Peak Factor
2013
1,618.35
284,749.2
305,350.8 Off-Peak factor
2014
1,651.36
290,556.8
311,578.6 Days Year
2015
1,684.37
296,364.4
317,806.4
2016
1,704.76
299,952.6
321,654.2
2017
1,725.15
303,540.8
325,502.1
2018
1,745.55
307,129.1
329,349.9
2019
1,765.94
310,717.3
333,197.7
2020
1,786.33
314,305.5
337,045.5
2021
1,799.26
316,580.0
339,484.6
2022
1,812.19
318,854.6
341,923.7
2023
1,825.12
321,129.1
344,362.8
2024
1,838.04
323,403.6
346,801.9
2025
1,850.97
325,678.1
349,241.0
2026
1,864.98
328,142.4
351,883.5
2027
1,878.98
330,606.7
354,526.1
2028
1,892.99
333,070.9
357,168.7
2029
1,906.99
335,535.2
359,811.2
2030
1,921.00
337,999.5
362,453.8
2031
1,926.26
338,924.6
363,445.9
2032
1,931.51
339,849.8
364,438.0
2033
1,936.77
340,774.9
365,430.0
2034
1,942.03
341,700.1
366,422.1
2035
1,947.29
342,625.3
367,414.2
165
153
212
1.15
0.89
365
For example, to find the off-peak demand in 2025, multiply the average daily demand of
1850.97 by days of off-peak demand per year of 212, and then multiply this value by the offpeak demand factor of 0.77 to find a value of 325687.1. This is the estimated yearly off-peak
demand in 2025 in AF.
Variable Operating Costs
The next spreadsheet requires data on the system components which have costs that vary
with total water production. System components that do not have variable costs are not included.
All estimates are derived from 2010 data because this is the last year all necessary data has been
made publically available by the LADWP. Of the five components added to the model, only
marginal costs for the MWD and Water Transfer component was possible to calculate. Because
currently available public data is limited, the average costs for the components of Groundwater
and Los Angeles Aqueduct were inputted into the model. The average costs give a close
approximation to marginal costs and as more information becomes available from the LADWP
these values will be updated with marginal costs data. Each water source will be described in
detail:
MWD. LAWDP’s 2010 UWMP provides data on the unit costs of LADWP’s water supplies in
dollars per AF. The MWD uses a two-tiered pricing system to encourage water districts to
develop their own sources of supply. LADWP is allocated 304,970 AF of water at a tier-one rate
of $527 and any water purchases above this amount is charged the tier-two rate of $869
(LADWP, 2010a). From 2006 to 2010 LADWP averaged 326,012 AF of water imported from the
MWD. Further, they expected their MWD imports to decline to 168,027 AF by 2034-35 as local
sources of water are developed (LADWP 2010a). In future periods LADWP will primarily
import MWD water at tier-one rates and the tier-one rate of $527 will be used for this analysis
for the MWD purchase cost.
Groundwater. LADWP sources groundwater from the San Fernando, Sylmar, Eagle Rock,
Central, and West Coast water basins (2010 UWMP).From 2006 to 2010 LADWP averaged
71,087 AF of groundwater production per year at an average cost of $215 per AF (LADWP
2010a). The costs incurred by the district are primarily associated with operations and
maintenance costs and it was not possible to derive marginal costs.
LA Aqueduct. LADWP imports water from the eastern Sierra Nevada using the LA Aqueduct
system, which starts in the Mono Basin and extends 340 miles to Los Angeles. From 2006 to
2010 LADWP averaged 221,289 AF of imported water using the LA Aqueduct at an average cost
of $563 per AF. The costs incurred by the district are primarily associated with operations and
maintenance costs and it was not possible to derive marginal costs (LADWP 2010a).
Water Transfers.LADWP is currently developing the ability to increase its water supplies with
the use of water transfers from other agencies. A portion of the LA Aqueduct supply of water is
166
being set aside for environmental enhancements in the Sierra Nevada and water transfers will
help compensate for this loss of water supply. Transfers are estimated to begin in the year 2020
when the Neenach Pumping facility will finish construction. Cost estimates range from $440 to
$540 and the average of $490 will be used for this report.
Recycled Water. The LADWP’s recycled water infrastructure is currently being expanded with
over $500 million dollars planned for recycled water projects over the next 10 years (Water
System Capital Improvements Program). The cost of recycled water is estimated to be between
$600 and $1,500 per AF. These values include recycled water’s capital, operation, and
maintenance costs. It is difficult to estimate exactly what proportion is the variable cost
component and the lower end range of $600 will be used for the variable cost estimate to be
conservative.
The model sets default rates for “Annual Real Escalation Rates” which reflect real price
increases beyond inflation. The “Power Costs” value of 1.00% is based on forecasts by
the California Energy Commission for future energy cost increases. The default rate for
“Purchase Costs” is 2.00% representing CUWCC’s estimate of the increasing price of
water supply based on historic trends.
Figure 6: Variable Operating Costs Spreadsheet
Variable Operating Costs
Number of Components?
Component
Type
Su
Su
Su
Su
Su
Component Name
Existing On-Line
or
Year (for
Planned? Planned)
Los Angeles Aqueduct
Groundwater
MWD
Water Transfer
Recycled Water
e
e
e
e
p
Loss
Rate
2015
Annual Real
Escalation Rates:
Power
Costs (2010
dollars)
Chemical
Costs
(2010
dollars)
Purchase
Costs
(2010
dollars)
Other
Costs
(2010
dollars)
Revenues
(2010
dollars)
($/AF)
($/AF)
($/AF)
$563
$215
$527
$490
$600
($/AF)
($/AF)
1.00%
0.00%
2.00%
0.00%
0.00%
On-Margin probabilities
The model’s next input spreadsheet requires data on the district’s “On-Margin
Probabilities”. A system component is considered to be “on-margin” if its operation would be
scaled back in response to conservation efforts leading to demand reductions. If a component’s
operation would not be scaled back due to reduced demand its “on-margin” probability is zero.
If a unit of demand reduction always caused a system component to reduce output by the same
amount, its “on-margin” probability would be 100%.
The “on-margin” probabilities for the district’s system components are determined by
many factors including economic, operational, and regulatory.It is difficult to determine precise
values based on the district’s public documents but estimates can be made from studying their
operational strategy.
167
The LADWP is attempting to lower their reliance on water imported from the MWD and
increase its use of local supplies. The higher tier-two rate for MWD water of $869 represents the
highest water supply cost for LADWP. The 2010 UWMP displays their current water supply mix
and their expected supply mix in the year 2034-35 (Figure 7.5, LADWP 2011a ):
Figure 7.5 LADWP Water Supply
As Figure 7.5 displays, the amount of imported MWD water is expected to fall
significantly from 52% to 24% of total supply. The development of local water supplies such as
local groundwater water and water transfers will make up this difference.
From the current period to the model’s timeline end of 2035 the “on-margin”
probabilities of imported MWD is 100% (Figure 7.6).Any conservation led efforts that lead to an
amount of demand reduction will lead to a corresponding reduction in the amount of water
imported from the MWD.
LADWP’s amounts of water supplied from Groundwater, LA Aqueduct, and Water
Transfers are all estimated to remain constant or increase. Therefore, their “on-margin”
probabilities are all estimated to be zero (Figure 7.6). A unit of water conservation created
demand reduction will not have an affect on the amount of water supplied from Groundwater,
Los Angeles Aqueduct, and Water Transfers.
168
Figure 7.6 “On-Margin” Probabilities Spreadsheet
System Components:
On-Margin Probabilities
Los Angeles Groundwate
Aquaduct
r
MWD
On-line dates:
Year
Season
2010
to 2014
2015
to 2019
2020
to 2024
2025
to 2029
2030
to 2034
2035
to 2039
Peak
Off-Peak
Peak
Off-Peak
Peak
Off-Peak
Peak
Off-Peak
Peak
Off-Peak
Peak
Off-Peak
Type:
Water
Transfer
2020
Su
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Su
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Su
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
100%
SU
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
0%
Short-Run Avoided Costs
Figure 7.7, below, displays the model’s output values for short-run avoided costs based
on the data added to the model in the previous spreadsheets.
169
Figure 7.7 Short-Run Avoided Costs Spreadsheet
Short-Run Avoided Costs
($/AF)
Annual Short-Run
Avoided Costs by Season
Nominal Dollars
Annual Short-Run
Avoided Costs by Season
2010 Dollars
Year
PeakSeason
Off-Peak
Season
Year
PeakSeason
Off-Peak
Season
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
$560.64
$583.29
$606.85
$631.37
$656.88
$683.41
$711.02
$739.75
$769.64
$800.73
$833.08
$866.74
$901.75
$938.18
$976.08
$1,015.52
$1,056.55
$1,099.23
$1,143.64
$1,189.84
$1,237.91
$1,287.92
$1,339.96
$1,394.09
$1,450.41
$1,509.01
$560.64
$583.29
$606.85
$631.37
$656.88
$683.41
$711.02
$739.75
$769.64
$800.73
$833.08
$866.74
$901.75
$938.18
$976.08
$1,015.52
$1,056.55
$1,099.23
$1,143.64
$1,189.84
$1,237.91
$1,287.92
$1,339.96
$1,394.09
$1,450.41
$1,509.01
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
$560.64
$571.85
$583.29
$594.95
$606.85
$618.99
$631.37
$644.00
$656.88
$670.01
$683.41
$697.08
$711.02
$725.25
$739.75
$754.55
$769.64
$785.03
$800.73
$816.74
$833.08
$849.74
$866.74
$884.07
$901.75
$919.79
$560.64
$571.85
$583.29
$594.95
$606.85
$618.99
$631.37
$644.00
$656.88
$670.01
$683.41
$697.08
$711.02
$725.25
$739.75
$754.55
$769.64
$785.03
$800.73
$816.74
$833.08
$849.74
$866.74
$884.07
$901.75
$919.79
The model outputs both nominal values and real 2010 monetary values. It gives the
amount of money the district will save per AF of demand reduction in future periods. For
example, in the year 2020 an AF of lowered demand in the peak season will save the district
$833.08 nominal dollars and $683.41 real 2010 dollars. The model assumes a 2.00% real
escalation rate for water supply costs beyond inflation based on historical trends leading to the
increase in value of short-run avoided costs in real 2010 dollars. Further, the nominal values for
avoided cost savings increase at a higher rate than real cost values because of inflation, estimated
in the model to be 2.00%.
Planned System Additions
The model’s next input spreadsheet represents the water district’s planned system
additions which are used to calculate long-run avoided costs (Figure 7.8).The only system
additions included are those that would be deferred or downsized due to future reduced water
demand.
170
Figure 7.8 Planned System Additions
Planned System Additions
Number of Projects?
If Downsize, then:
Project Name
Recycled Water
On-line
Year
2015
Annual Real Escalation Rates:
Financing Term (yrs):
Capital
Cost
Fixed O&M
De fer/
Downsize
Cost
Do wnsize?
Factor
($million)
($/yr)
Year 2010
Dollars
$510
Year 2010
Dollars
1%
1%
Flow/
Volume?
Size
Units
Size
(Peak
Season)
de
20
LADWP is planning to develop an extensive water recycling infrastructure to help lower
its demand of imported water. It will increase by six fold the amount of recycled water used,
from 1% to 6% of annual water demand by the year 2019. Recycled water projects include
increasing the amount of recycled water used for irrigation and industry (Securing LA’s Water
Supply). Further, upgrades of wastewater treatment plants will allow the use of recycled water in
replenishing groundwater basins (Securing LA’s Water Supply).
LADWP estimates that from 2009 to 2019 $510,402,000 will be spent on recycled water
projects (Water System Capital Improvements Program). This value is inputted into the planned
system additions spreadsheet as a possible deferred cost.
Total Direct Utility Avoided Costs
The model’s final output spreadsheets give the total avoided costs to the district by
combining the short-run avoided costs with the long-run avoided costs. Total avoided costs are
given in nominal values, Figure 7.9, and 2010 dollars, Figure 7.10.
The spreadsheets estimates how much the district will save per AF of demand reduction
until 2035 and demonstrates that adding the ability to defer future water system additions has a
significant effect on avoided costs. For example, in the year 2020 peak season short-run avoided
costs in 2010 dollars are estimated to be $683 dollars. Taking into account the ability to defer
system additions, the long-run avoided cost of $685 brings the total avoided costs value to
$1,368 dollars—significantly higher than the short-run cost estimates.
Figure 7.9 Total Direct Utility Avoided Costs in Nominal Dollars
171
Total Direct Utility Avoided Costs: Nominal Dollars
($/AF)
Year
Peak Season
Short-Run Long-Run
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
$561
$583
$607
$631
$657
$683
$711
$740
$770
$801
$833
$867
$902
$938
$976
$1,016
$1,057
$1,099
$1,144
$1,190
$1,238
$1,288
$1,340
$1,394
$1,450
$1,509
$0
$0
$0
$0
$0
$835
$835
$835
$835
$835
$835
$835
$835
$835
$835
$835
$835
$835
$835
$835
$835
$835
$835
$835
$835
$0
Off-Peak Season
Total
Short-Run
Long-Run
Total
$561
$583
$607
$631
$657
$1,518
$1,546
$1,574
$1,604
$1,635
$1,668
$1,701
$1,736
$1,773
$1,811
$1,850
$1,891
$1,934
$1,978
$2,025
$2,073
$2,123
$2,175
$2,229
$2,285
$1,509
$561
$583
$607
$631
$657
$683
$711
$740
$770
$801
$833
$867
$902
$938
$976
$1,016
$1,057
$1,099
$1,144
$1,190
$1,238
$1,288
$1,340
$1,394
$1,450
$1,509
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$561
$583
$607
$631
$657
$683
$711
$740
$770
$801
$833
$867
$902
$938
$976
$1,016
$1,057
$1,099
$1,144
$1,190
$1,238
$1,288
$1,340
$1,394
$1,450
$1,509
Figure 7.10 Total Direct Utility Avoided Costs in 2010 dollars
Total Direct Utility Avoided Costs: 2010 Dollars
($/AF)
Year
Peak Season
Short-Run Long-Run
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
$561
$572
$583
$595
$607
$619
$631
$644
$657
$670
$683
$697
$711
$725
$740
$755
$770
$785
$801
$817
$833
$850
$867
$884
$902
$920
$0
$0
$0
$0
$0
$756
$741
$727
$712
$698
$685
$671
$658
$645
$633
$620
$608
$596
$584
$573
$562
$551
$540
$529
$519
$0
Off-Peak Season
Total
Short-Run
Long-Run
Total
$561
$572
$583
$595
$607
$1,375
$1,373
$1,371
$1,369
$1,368
$1,368
$1,368
$1,369
$1,370
$1,372
$1,375
$1,378
$1,381
$1,385
$1,390
$1,395
$1,400
$1,407
$1,413
$1,421
$920
$561
$572
$583
$595
$607
$619
$631
$644
$657
$670
$683
$697
$711
$725
$740
$755
$770
$785
$801
$817
$833
$850
$867
$884
$902
$920
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$0
$561
$572
$583
$595
$607
$619
$631
$644
$657
$670
$683
$697
$711
$725
$740
$755
$770
$785
$801
$817
$833
$850
$867
$884
$902
$920
Deriving the total avoided cost values is the conclusion to the first step of the costefficiency methodology.
172
Conservation
This next conservation section of the report completes step two of the cost-efficiency
methodology. It uses publicly available data on the LADWP’s conservation measures to analyze
their costs per unit of water savings. The available data is not complete but gives a good
overview of the district’s programs and will be compared with the CUWCC model’s avoided cost
estimates to assess cost-efficiency.
The LADWP’s 2010 UWMP provides data on their residential and commercial water
conservation measures. Using the data the costs per AF of each conservation measure is
calculated and displayed graphically (See Appendix 1 for calculations). Figure 13 displays the
costs per AF for residential conservation measures and Figure 14 for commercial measures.
Figure 7.11 Residential Water Conservation Measure’s Average Costs
Cost-Efficiency
With the CUWCC model’s estimates for total avoided cost derived and the data on the
LADWP’s conservation measures used to find their costs per AF, the cost-efficiency of each
conservation measure can be calculated. Two methods will be used to examine cost-efficiency.
First, the costs and benefits of conservation measures in specific years will be compared.
Second, benefit-cost ratios for each conservation measure will be calculated.
173
The first cost-efficiency method is comparing the cost of measures in each year with their
benefits in each year. Calculating the costs of conservation measures in future years is the first
step. Using the model’s assumption of a 2% inflation rate (Common Assumptions Spreadsheet),
the future costs of the programs are found based on their 2010 values (Appendix 2). These
calculations are completed using the future costs equation of F = P(1+i)^n, where F is future
cost, P is the present or 2010 value, i is inflation rate, and n is periods from current period. Future
values were calculated up to 2020.Then, the values for each year were compared graphically to
the avoided cost values for each year to 2020 (Figure 7.12, 7.13).
Figure 7.12: Residential Conservation Costs and Benefits Comparison
Figure 7.12 displays the costs in each year of each residential conservation measure and
the short-run and total avoided costs in each year. In the year 2012, for example, the only
measure that is not cost-efficient is “High-Efficiency Clothes Washers.” In the year 2015 total
avoided costs increase over short-run avoided costs—this is the first year a planned system
addition can be deferred by water demand reduction. All the residential conservation measures
are cost-efficient when considering both short-run and long-run avoided costs (total avoided
costs).
174
Figure 7.13 displays the same comparison but with the LADWP’s commercial measures. Again,
when including both short-run and long-run avoided costs, all the commercial conservation
measures are cost-efficient.
Figure 7.13 Commercial Conservation Costs and Benefits Comparison
Benefit-Cost Ratios
The last step in the cost-efficiency analysis is calculating the benefit-cost ratio for each
conservation measure. A benefit-cost ratio gives the value of the benefits of a measure divided by
the measure's costs. Any measure with a ratio greater than one is considered a cost-efficient
investment because the monetary benefits from the measure have a higher value than the
measure's costs. Further, the greater the benefit-cost ratio value of a measure the more costefficient the measure is for the district. For example, a measure with a benefit-cost ratio of two
indicates the financial benefits of the measure are double its costs.
The following methodology is used to find the benefit-cost ratios for the district's
measures. For the years 2010 and 2015, the total avoided cost value of an AF of water savings in
each year —the benefit—is divided by the cost of implementing the measure for an AF of water
savings (See Appendix 3 for data). The resulting values are displayed in Table 7.5, below. For
example, to find the benefit-cost ratio of “High Efficiency Toilets” in 2015, the total avoided cost
value in 2015 of an AF of water savings of $1,375 is divided by the cost to the district of an AF
savings for “High Efficiency Toilets” of $131.1 to find a benefit-cost ratio of 10.49. This value of
175
10.49 indicates that “High Efficiency Toilets” are cost-efficient for the district to implement in
the year 2015 and for every dollar invested the district can expect a return of over ten dollars.
Only two conservation measures were found not to be cost-efficient for the district, "High
Efficiency Clothes Washers" in 2010 with a benefit-cost ratio less than one of 0.70 and
“Waterless Urinals” in 2010 with a benefit-cost ratio less than one of 0.92.Starting in 2015 the
total avoided cost values for the district increase significantly over the 2010 value because the
long-term savings of deferred water system components is taken into account and both measures
become cost-efficient for the district with a benefit-cost ratio of 1.55 for "High Efficiency
Clothes Washers" and 2.05 for “Waterless Urinals”. These calculations demonstrate that
LADWP’s conservation measures are all cost-efficient when considering both short-run and
long-run avoided cost (Table 7.5).
Table 7.5 Benefit-Cost Ratios of Conservation Measures
Conservation Measure
2010 Benefit/Cost
Residential:
High Efficiency Toilets
High Efficiency Clothes Washers
Rotating Nozzles for Pop-up Spray
Heads
Weather Based Irrigation Controllers
Commercial:
High Efficiency Toilets
Waterless Urinals
Weather Based Irrigation Controllers
Rotating Nozzles for Pop-up Spray
Heads
2015 Benefit/Cost
4.72
0.70
10.49
1.55
24.76
4.29
54.96
9.53
3.08
0.92
72.95
6.84
2.05
161.95
3.08
6.85
To help visualize the calculated benefit-cost ratios the 2010 and 2015 values have been graphed
in Figure 7.14, below. Every conservation measure in 2015 is cost-efficient for the district. The
graph clearly demonstrates which measures have the highest cost-efficiency for the district—the
measures that reach the farthest to the right of the graph. The district should place highest
priority on expanding these measures, such as “Weather Based Irrigation Controllers” and
“Rotating Nozzles for Pop-up Spray Heads.”
Figure 7.14 Benefit-Cost Ratio Graph
176
Rotating Nozzles for
Pop-Up Spray Heads
Commercial
160.95
Weather Based
Irrigation Controllers
Commercial
Waterless Urinals
Commercial
High Efficiency Toilets
Commercial
2015 Benefit/Cost
Weather Based
Irrigation Controllers
Residential
2010 Benefit/Cost
Rotating Nozzles for
Pop-Up Spray Heads
Residential
High Efficiency
Washers - Residential
High Efficiency Toilets
Residential
0
10
20
30
40
50
60
70
80
90
100
Benefit-Cost Analysis for Cucamonga Valley Water District
The same cost-efficiency methodology applied above to the LADWP was applied to the
Cucamonga Valley Water District (CVWD) in Southern California, including the use of the
excel model developed by the California Urban Water Conservation Council (CUWCC).
Inputs for CVWD
The CUWCC model’s inputs include the CVWD’s future water demand estimates, its
water system components and their variable operating costs, the “on-margin” probabilities of the
water system components, and the planned water system additions. Using these inputs the model
forecasts the CVWD’s short-run, long-run, and total avoided costs values of reduced water
demand for each year up to 2035. Table 7.6 identifies the inputs used for running the model.
177
The projected interest rate of 6% was based on two recent bond issues, a 2006 bond issue
of $21M with interest rates ranging from 3.42% to 5%, and a 2009 bond issue of $28M with
interest ranging from 2% to 5.625%.
The forecasted demand was interpolated for each year using the 5-year UWMP estimates
beginning in 2010. Note that CVWD expects demand to decline from 2015-2020. The CUWCC
model, however, requires demands to be increasing over the planned period. The model’s user
manual explains, “the model’s long-run avoided cost calculation requires demands to be
increasing over the planned period” (Report, p. 39). To take this problem with the model into
account, starting in 2016 and until the projections increase to pre-2016 levels, the input values
were increased by one unit in each period to satisfy this requirement.
On peak factors, note that the peak factor for CVWD’s service area (1.32) is much higher
than LADWP’s (1.15). This is most likely due to the higher temperatures, larger lots, and greater
outdoor water use in CVWD’s service area. Also note that of the four variable cost components
added to the model, only marginal costs for the MWD was calculated. Currently available data
was limited, and the average costs for the components of Groundwater, Water Treatment and
Transmission were calculated and included as inputs to the model.
“On-margin” probabilities are determined by many factors including economic,
operational and regulatory. It was difficult to determine precise values based on the district’s
public documents but estimates were made based on an examination of CVWD’s operational
strategy.
The CVWD draws water from two main sources, imported water from the MWD and
water pumped from local groundwater basins. In the district’s 2012 Annual Budget their
reasoning for moving away from imported MWD water was outlined:
In our formative years, our water supply planning strategy was to secure an outside water
supply that would supplement local resources and allow the region to grow. As the cost
of imported water began to increase due to a number of outside influences, including
environmental degradation in the Sacramento-San Joaquin Delta, it caused our
organization to focus on the development of local supplies in an effort to become less
reliant on imported water. (Budget pg. 6)
The district is responding to the increasing costs of MWD imported water by further
developing its ability to draw water from local sources. Unfortunately, recent multiple dry-year
conditions are affecting the district’s ability to increase water supply from local sources and
decrease supply from imported sources:
The availability of replenishment water is critical for the sustainability of our local
groundwater basins and helps the District maintain a diverse water supply portfolio.
Typically, in wet years, when supplemental supplies of imported water are available,
Metropolitan Water District of Southern California (MWD) has made this water available
at a discounted price to create an incentive for groundwater agencies to use local supplies
during dry years. [Because of drought] Replenishment supplies have not been available
for nearly four years. (Budget pg. 12)
178
Table 7.6. CVWD Input Variables for Benefit-Cost Analysis
Variables
Inputs
Notes
Projected Interest Rate
6%
Based on recent bond issues
Forecasted Demand
Year
2010
2015
2020
2025
2030
2035
Peak Average
June-Oct
Acre Feet
48,591
57,600
56,300
58,100
60,100
61,900
5,674.90 AF
Peak Factor
1.32
Off-Peak
Average NovMay
3,296.01 AF
Peak and Off-Peak Factors
Off-Peak
Factor
0.77
4,287.24 AF
Monthly
Average
Variable Operating Costs
for 4 Water Components of
CVWD
Power
Costs
($/AF)
Chemical
Costs
($/AF)
MWD
Groundwater
Water Treatment
$51
Transmission
$54
Annual Escalation
Rate
1.00%
Annual figures were
interpolated using 5-year
UWMP estimates beginning
in 2010. Note the estimated
decline between 2015 and
2010.
0.00%
179
Purchase Spreadsheet model requires
Costs
data on the district’s water
($/AF)
system components that have
operating costs that vary with
total water production. All
$539
estimates are based on 2010
data. It was assumed that
CVWD water demand for
$211
MWD imports would not
increase through 2035 to
require Tier 2 imports. Cost
estimates are based on
CVWD’s 2012 Annual
Budget reports.
2.00%
On-Margin Probabilities of
System Components
Scaling Back Due to
Conservation Efforts
Assume a split between MWD
and Groundwater components
being scaled back:
Short-Run Avoided Costs
Year
2010-2014 MWD 60%;
Groundwater 40% with an
increasing percentage attributed
to MWD imports over time
projected to 2039: 2035-2039
MWD 75%; Groundwater 25%
2010
2015
2020
2025
2030
2035
Planned System Additions
New Well # 48
New Well # 49
New Reservoir
On-line
Year
2015
2020
2015
Nominal
Dollars
$449
$564.15
$708.63
$889.80
$1,080.66
$1,312.84
2010
Dollars
$449.
$510.97
$581.32
$661.13
$727.26
$800.22
$6
$0
Based on CVWD 2012
Annual Budget statements
regarding plans to increase
groundwater sources
motivated by reducing MWD
imports due to increasing
costs of imports.
This variable estimates the
amount of money that the
District will save per AF of
demand reduction in future
periods. As on-margin
probability of MWD offsets
increases over time (from
60% to 75%), savings will
increase; in addition, the
assumption of 2% escalation
rate for MWD imports also
increases savings.
Capital
Fixed O CVWD 2012 Annual Budget
Costs
& M cost reports three planned system
($Millions ($/yr
components. It also indicates
and 2010 2010
that the new wells and
Dollars)
Dollars
reservoirs will have no
operational impact on
$3
$0
expenses (Budget pp. 99100)
$3
$0
Further, the district states:
…two conditions have impacted the way we manage our portfolio of water resources:
prolonged natural and man-made drought, and the increased cost of groundwater
production due to the inability to find cost-effective, reliable and sustainable
replenishment supplies. The increased cost of assessments on groundwater pumping and
the challenges associated with securing replenishment water have severe implications
related to the sustainability of groundwater as an alternative to imported water. (Budget
pg. 6)
180
It is not clear from these and other statements exactly which system component would
lower production because of conservation created demand reductions. The district’s goal is to
move away from more expensive imported water sources but challenges in sustaining their local
groundwater supply has kept imported water as a significant portion of their supply portfolio.
To increase production of local water supplies, the district is spending millions of dollars
building new pumping wells and a reservoir that will “help reduce the District’s reliance on
imported water.” (Budget pg. 109) As these capital improvement projects come on-line, the
district will be able to lower their yearly demand for imported water. Because of this the “onmargin” probabilities of imported MWD water are estimated to increase over time. This
reasoning led us to estimate that the MWD “on-margin” probability begin at 60% in 2010 and
increase to 75% by 2025. The Groundwater probabilities decrease in the same time-frame from
40% to 25%.
The model outputs both nominal values and real 2010 monetary values for short-run
avoided costs. It gives the amount of money the district will save per AF of demand reduction in
future periods. For example, in the year 2020 an acre-foot of lowered demand in the peak season
will save the district $708.63 nominal dollars and $581.32 real 2010 dollars. The real cost values
are increasing because of several factors. As the “on-margin” probability percentages for
imported MWD water increase, there will be increased savings from reducing demand, because
imported water is more expensive than locally sourced water. Further, the model assumes a
2.00% real escalation rate for water supply costs beyond inflation based on historical trends. The
nominal values for avoided cost savings increase at a higher rate than real cost values because of
inflation, estimated in the model to be 2.00%.
Inputs for the planned system components were obtained from the district’s 2012 Annual
Budget reports. The reports identify three planned system components designed to increase water
supply production, two wells and one reservoir. Their construction costs are estimated to be $3
million each for the wells and $6 million for the reservoir (Budget pg. 85-86). The wells are
being created specifically to “…help reduce District's reliance on imported water,” (Budget pg.
109) and the reservoir to “improve storage capacity” (Budget pg. 111) of local water supplies.
To determine whether these planned system components would be deferred or downsized
due to water conservation measures the following methodology was used. The district’s 2005
UWMP lists well #48’s completion date to be in 2008 but as of 2012 the well had still not been
completed (2005 UWMD Table 17) (Budget pg. 85). Further, 2007 – 2008 was the first year the
district experienced its current unexpected downward trajectory of water demand (Appendix 5).
It is assumed the district deferred construction of the well because of this unexpected drop in
demand. This indicates the district will defer its planned water system additions in response to
reductions in water demand, allowing water system additions to be added to the spreadsheet as
deferred system components.
The 2012 Annual Budget states that new wells and reservoir will have no “operational
impact” on expenses leading to values of zero in the “Fixed O&M Cost” column. (Budget pg. 99,
100)
181
Conservation
The conservation section of the CVWD study completes step two of the cost-efficiency
methodology. It used publicly available data on the CVWD’s conservation measures to analyze
their costs per unit of water savings. The available data is not complete but gives a good
overview of the district’s programs and will be compared with the CUWCC’s avoided cost
estimates to assess cost-efficiency.
Figure 7.15 graphically displays data on the costs per AF of the district’s residential
water conservation measures from 2004 to 2010 (See Appendix 7 for data). Figure 7.16
graphically displays data on the costs per AF of the district’s commercial water conservation
measures from 2004 to 2010 (See Appendix 8 for data).
The data is taken from the Inland Empire Utilities Agency’s (IEUA) annual conservation
report which includes a section on CVWD’s water conservation programs (Conservation Section
6). The values are the direct costs to the CVWD and do not include costs to society as a whole.
As the graphs demonstrate, not all yearly cost values were available.
Figure 7.15 Residential Water Conservation Measures Cost Per AF of Savings
Residential Water Conservation Measures
$600
High Effeciency Toilets
Cost per Acre-Foot
$500
Ultra Low Flush Toilets
$400
Rotating Nozzles for
Pop-up Spray Heads
$300
High Effeciency
Clothes Washers
$200
Weather Based
Irrigation Controllers
$100
Synthetic turf
$0
2004
2005
2006
2007
2008
2009
Year
182
2010
IEUA Multi-Family Direct
Install Prog.
Figure 7.16 Commercial Water Conservation Measures Cost Per AF of Savings
Commercial Water Conservation Measures
$400
Cost per Acre-Foot
$350
High Efficiency Toilets
$300
$250
Waterless Urinals
$200
$150
Weather Based
Irrigation Controllers
$100
ULFT Tank
$50
Rotating Nozzles for
Pop-up Spray Heads
$0
2004
2005
2006
2007
2008
2009
2010
Year
From this data the average costs of each conservation measures were calculated and
displayed graphically in figures 7.17 and 7.18.
Figure 7.17 Residential Water Conservation Measure’s Average Costs
183
Figure 7.18 Commercial Water Conservation Measure’s Average Costs
Cost-Efficiency
With the CUWCC model’s estimates for total avoided cost derived and the data on the
CVWD’s conservation measures used to find their average costs, the cost-efficiency of each
conservation measure can be calculated. Two methods will be used to examine cost-efficiency.
First, the costs and benefits of conservation measures in specific years will be compared.
Second, benefit-cost ratios for each conservation measure will be calculated.
The first cost-efficiency method is comparing the cost of measures in each year with their
benefits in each year. Calculating the costs of conservation measures in future years is the first
step. Using the model’s assumption of a 2% inflation rate (Common Assumptions Spreadsheet),
the future costs of the programs are found based on their 2010 values (Appendix 10). These
calculations are completed using the future costs equation of F = P(1+i)^n, where F is future
cost, P is the present or 2010 value, i is inflation rate, and n is periods from current period.
Future values were calculated up to 2020. Then, the values for each year were compared
graphically to the avoided cost values for each year to 2020 (Figures 7.19, 7.20).
184
Figure 7.19 Residential Conservation Costs and Benefits Comparison
Figure 7.19 displays the costs in each year of each residential conservation measure and the
short-run and total avoided costs in each year. In the year 2012, for example, the only measure
that is not cost-efficient is “Synthetic Turf.” In the year 2015 total avoided costs increase over
short-run avoided costs—this is the first year a planned system addition can be deferred by water
demand reduction. All the residential conservation measures are cost-efficient when considering
both short-run and long-run avoided costs (total avoided costs).
Figure 7.20 displays the same comparison but with the CVWD’s commercial measures. In each
year the costs from commercial measures are less than the avoided cost benefits to the district in
the short-run and short-run plus long-run (total avoided costs).
185
Figure 7.20 Commercial Conservation Costs and Benefits Comparison
Benefit-Cost Ratios
The last step in the cost-efficiency analysis is calculating the benefit-cost ratio for each
conservation measure. A benefit-cost ratio gives the value of the benefits of a measure divided
by the measure's costs. Any measure with a ratio greater than one is considered a cost-efficient
investment because the monetary benefits from the measure have a higher value than the
measure's costs. Further, the greater the benefit-cost ratio value of a measure the more costefficient the measure is for the district. For example, a measure with a benefit-cost ratio of two
indicates the financial benefits of the measure are double its costs.
The following methodology is used to find the benefit-cost ratios for the district's
measures. For the years 2010 and 2015, the total avoided cost value of an AF of water savings in
each year —the benefit—is divided by the cost of implementing the measure for an AF of water
savings (See Appendix 10 for data). The resulting values are displayed in Table 7.7, below. For
example, to find the benefit-cost ratio of “Ultra Low Flush Toilets” in 2015, the total avoided
cost value in 2015 of an AF of water savings of $606 is divided by the cost to the district of an
AF savings for “Ultra Low Flush Toilets” of $86.9 to find a benefit-cost ratio of 6.97. This value
186
of 6.97 indicates that “Ultra Low Flush Toilets” are cost-efficient for the district to implement in
the year 2015 and for every dollar invested the district can expect a return of almost seven
dollars.
The only conservation measure found not to be cost-efficient for the district is "Synthetic
Turf" in 2010 with a benefit-cost ratio less than one at .96. Starting in 2015 the total avoided
cost values for the district increase significantly over the 2010 value because the long-term
savings of deferred water system components is taken into account and "Synthetic Turf"
becomes cost-efficient for the district with a benefit-cost ratio of 1.17. These calculations
demonstrate that the CVWD’s conservation measures are all cost-efficient when considering
both short-run and long-run avoided cost.
Table 7.7 Benefit-Cost Ratios of Conservation Measures
Conservation Measure
2010 Benefit-Cost Ratio
2015 Benefit-Cost
Ratio
Residential:
Ultra Low Flush Toilets
High Efficiency Toilets
High Efficiency Clothes Washers
Rotating Nozzles for Pop-up Spray Heads
Weather Based Irrigation Controllers
Synthetic Turf
IEUA Multi-Family Direct Install Program
5.70
2.24
1.57
2.00
11.11
0.96
1.92
6.97
2.74
1.92
2.44
13.58
1.17
2.35
Commercial:
High Efficiency Toilets
Waterless Urinals
Weather Based Irrigation Controllers
Rotating Nozzles for Pop-up Spray Heads
1.55
2.75
2.01
2.25
1.89
3.37
2.45
2.74
To help visualize the calculated benefit-cost ratios the 2010 and 2015 values have been graphed
in Figure 7.21, below. The red vertical line represents the benefit-cost ratio break-even point for
the district of one. Every conservation measure to the right of this red line is cost-efficient for the
district. The graph clearly demonstrates which measures have the highest cost-efficiency for the
district—the measures that reach the farthest to the right of the graph. The district should place
highest priority on expanding these measures, such as “Weather Based Irrigation Controllers”
and “Ultra Low Flush Toilets.”
187
Figure 7.21 Benefit-Cost Ratio Graph
Rotating Nozzles CII
Weather Based
Irr. Controllers CII
Waterless Urinals
CII
High Efficiency Toilets
CII
IEUA Direct Install Program
Residential
2015 Benefit-Cost Ratio
Synthetic Turf
Residential
2010 Benefit-Cost Ratio
Weather Based
Irr. Controllers Residential
Rotating Nozzles Residential
High Efficiency
Washers - Residential
High Efficiency Toilets
Residential
Ultra Low Flush Toilets
Residential
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
Limitations of the Analysis
There are specific steps that can be taken to increase the accuracy of this analysis. First, a
sensitivity analysis should be completed of CUWCC model's inputs. These include increased and
decreased values for projected future water demand, "on-margin" probabilities, variable
operating costs, and future water system additions. For example, how would avoided cost
estimates for LADWP be affected if the "on-margin" probability of MWD imported water is not
100% in each period? Or if for CVWD the “on-margin probability of MWD imported water is
100% in each period? Also, how would avoided cost estimates be affected if future water
demand increased faster or slower than currently projected?
Further, the accuracy of the data used for model inputs and conservation estimates could
be increased by access to agency data that were not available to the research team. Specifically,
more accurate data would allow the calculation of the marginal costs of water treatment and
transmission which would replace the average costs used currently.
In addition, a possible flaw in the CUWCC's model was found. The model would not
accept any periods of declining projected water demand. Declining demand is predicted for the
CVWD in the years 2016 through 2020. Allowing the model to accept declining demand would
possibly increase the accuracy of the model's output estimates of avoided costs and make the
model more useful to the many water districts estimating future periods of declining demand.
188
Finally, the question of the district’s motivation to reduce water demand beyond state
mandates should be addressed. The CVWD’s revenues are currently based on its amount of
water supplied. Its 2012 budget discusses the effect of lowered water demand:
A reduction in water sales of nearly 10,000 acre feet in three years has challenged our
ability to accurately project future revenues... In 2009 we instituted a workforce reduction
for the first time in our history. (Budget pg. 5)
Because of lowered water demand the district is dealing with reduced revenues and is
forced to layoff employees. This might create a situation in which the district avoids efforts to
reduce water demand beyond state mandates. Conservation measures add volatility to water
agency revenues, which may drive agencies away from conservation efforts and towards
investment in water supply initiatives, as discussed in Chapter 6.
Comparison of LADWP and CVWD Cost-Efficiency Analyses
The methodology used in the analysis takes into account many variables from the interest
rate on bonds to peak season, to projected demand and purchase cost of water supply sources.
Table 8 compares the benefit-cost ratios between the two districts.
Table 7.8 Comparison of LADWP’s and CVWD’s Benefit-Cost Ratios of Conservation BMPs
Conservation Measure
LADWP
CVWD
2010 Benefit2015 Benefit- 2010 Benefit- 2015 BenefitCost Ratio
Cost Ratio
Cost Ratio
Cost Ratio
Residential:
Ultra Low Flush Toilets
5.70
6.97
High Efficiency Toilets
4.72
10.49
2.24
2.74
High Efficiency Clothes
0.70
1.55
1.57
1.92
Washers
Rotating Nozzles for Pop24.76
54.96
2.00
2.44
up Spray Heads
Weather Based Irrigation
4.29
9.53
11.11
13.58
Controllers
Synthetic Turf
0.96
1.17
IEUA Multi-Family Direct
1.92
2.35
Install Program
Commercial:
High Efficiency Toilets
Waterless Urinals
Weather Based Irrigation
Controllers
Rotating Nozzles for Popup Spray Heads
3.08
0.92
6.84
2.05
1.55
2.75
1.89
3.37
72.95
161.95
2.01
2.45
3.08
6.85
2.25
2.74
189
As evident, although most of the BMPs have positive benefit-cost ratios, the ratios for the
same BMPs vary, in some cases, dramatically. For 2015, the benefit-cost ratio of high-efficiency
toilets for LADWP is close to 4 times the benefit-cost ratio for CVWD. Also, the benefit-cost
ratio for weather-based irrigation controllers is higher for CVWD than for LADWP.
Table 7.9 Comparison of Input Variables for LADWP and CVWD for Benefit-Cost Ratio
Analysis of Conservation BMPs
Variables in CUWCC
Model
Projected Increase of
Demand 2010-2035
Peak Factor
Off-Peak Factor
Purchase Costs of Water
Supply Sources ($/AF in
2010 dollars)
On Margin Probabilities of
Water Conservation
Savings to Offset MWD
Imported Water
Annual Short Run Avoided
Costs per Acre/Foot in
2010 dollars
Planned System Additions
Total Utility Avoided Costs
in 2010 Dollars
Costs of Residential Water
Conservation Measures per
Acre/Foot
LADWP
CVWD
From 554,556 AF to 710,760 AF
From 48,591 to 61,900 AF
1.15
0.89
LAA
Groundwater
MWD
Water Transfer
Recycled Water
100%
1.32
0.77
Groundwater $211
MWD
$539
$563
$215
$527
$490
$600
2010 $560
2015 $619
2020 $683
2035 $$920
Recycling Infrastructure $510 M
investment; Online in 2015
2010 Peak Season $561
Off-Peak
$561
2015 Peak Season $1,375
Off-Peak
$619
High Efficiency Toilets $118.75
High Efficiency Washers $801.63
Sprinklerhead Rotating Nozzle
$22.66
Weather-Based Irrigation
Controller $130.64
190
Increasing from 60% for MWD and
40% for Groundwater in 2010 to
75% by 2035 for MWD, 25% for
Groundwater
2010 $449
2015 $511
2020 $581
2035 $800
2015 $3M new well online
2015 $6M new reservoir online
2020 $3M new well online
2010 Peak Season $449
Off-Peak
$449
2015 Peak Season $606
Off-Peak
$511
High Efficiency Toilets $100
High Efficiency Washers $386.60
Sprinklerhead Rotating Nozzle $300.
Weather Based Irrigation Controller
$22.8
Synthetic Turf $535.6
Table 7.9 provides a comparison of the input variables included in the analysis for the
two districts. Some of these variables can throw light on the different results for the two districts.
First, notice that the 2015 benefit-cost ratios are always higher than the 2010 values for
both districts. To a large extent, this is due to the model’s taking into account how the savings
from the conservation measures can defer the capital costs of the planned system additions. The
assumption that investment in conservation measures can defer infrastructure investments in
2015 explains how the high efficiency clothes washer for LADWP or the synthetic turf for
CVWD changes from a negative benefit-cost ratio to a positive one. This assumption, however,
that the economic argument for conservation is based on the avoided costs of capital investment
for new water supply, is weakened in the case of Southern California water agencies. For these
agencies, in order to reduce the uncertainty of imported water supplies, are simultaneously
investing in increasing their own sources of supply.
The magnitude of the difference between LADWP’s planned investment ($500M in
recycling infrastructure) and CVWD’s planned investment ($9 M in 2 wells and a reservoir) to
some extent explains the doubling of the benefit-cost ratios for LADWP. But also, LADWP’s
annual short-run avoided costs are higher than CVWD, and part of this is explained by the
assumption that every AF saved through conservation by LADWP will offset imported water
from MWD, while in the case of CVWD, acre-feet saved through conservation is assumed to be
split between MWD and groundwater sources, and the cost of groundwater is lower. The
tremendous difference between the benefit-cost ratios for rotating nozzles for pop-up spray heads
for LADWP and the modest ones for CVWD can be explained by the relative cost of the rebate
per acre foot saved. The larger the agency rebate, the lower the benefit-cost ratio. In general, the
methodology used in the analysis is sensitive to planned infrastructure investments, the mix and
cost of different water sources, the cost of conservation rebates, as well as other relevant
variables. In effect, it demonstrates that developing a conservation strategy can be tailored to the
characteristics of the agency to obtain the targeted water savings.
Findings
Analysis Followed a Two-Step Methodology: Finding the Avoided Cost Value of Lowered
Water Demand, and Comparing this to Agency’s Conservation Costs and Water Savings. The
methodology applied to find the cost-efficiency of LADWP’s and CVWD’s conservation
measures for which costs have been quantified required two steps; finding the avoided cost value
to the districts of lowered water demand by completing the California Urban Water Conservation
Council’s (CUWCC) model and comparing this value to the agencies’ costs and water savings of
their conservation measures. The methodology described and used for the LADWP and CVWD
can be applied to other districts to find which of their conservation measures are the most costefficient.
191
CUWCC’s methodology is a useful and relatively simple analytic tool for water agencies to
calculate the avoided cost value of lowered water demand. CUWCC’s methodology is a useful
and relatively simple analytic tool to enable agencies to develop benefit-cost and cost-efficiency
analyses of conservation measures. The methodology does have a flaw that should be corrected.
At this time, it assumes ongoing growth in demand.
Methodology in Analysis Incorporates Infrastructure Investment, Cost of Water Sources and
Conservation Programs. In general, the methodology used in the analysis is sensitive to planned
infrastructure investments, the mix and cost of different water sources, the cost of conservation
rebates, as well as other relevant variables.
Methodology’s Assumption that Water Savings from Conservation Are Used to Defer Capital
Facilities May Not Hold, Reducing the Longer-term Benefit-Cost Ratio of Conservation
BMPs. The methodology makes an important assumption, that is, that water savings from BMPs
will be used to defer capital facilities for increasing own water supply sources. If water districts
pursue both new water supply and conservation, then the greater economic benefits of
conservation, which this methodology assumes, are not realized.
For LADWP, Almost All the State Recommended BMPs being Implemented are Cost-efficient
with Benefit-cost ratios of One or Greater. Further, the benefit-cost ratios of the conservation
measures vary greatly; some measures have ratios barely above one while others have ratios
above 20. For LADWP, because of its great reliance on costly MWD imported water, many
conservation BMPs have very high benefit-cost ratios. For example, outdoor water use
conservation devices for LADWP have exceptionally high benefit-cost ratios. This confirms
LADWP’s emphasis on outdoor water use conservation devices. The very high benefit-cost ratios
in 2015 are based on the assumption that the water savings from the conservation strategies will
be used to defer the agency’s capital investment plans for recycling facilities and other water
supply infrastructure. All other factors being equal, the differences in benefit-cost ratios can be
used by the district as an investment guideline for future implementation of conservation
measures.
For the CVWD, Almost All the State Recommended BMPs being Implemented are Costefficient with Benefit-cost Ratios of One or Greater. As in the case of LADWP, the benefit-cost
ratios of the conservation measures vary greatly; some measures have ratios barely above one
while others have ratios above 10. All other factors being equal, the differences in benefit-cost
ratios can be used by the district as an investment guideline for future implementation of
conservation measures. For CVWD, conservation BMPs have positive benefit-cost ratios
averaging about 2, with some exceptions. Ultra-low flush toilets for the residential sector have
benefit-cost ratios above 5, and weather-based irrigation controllers have a benefit-cost ratio
above 11. These two conservation measures can be prioritized by the district. Synthetic turf is
the one BMP with a benefit-cost ratio of .96 that, in the short-run, is borderline for the agency. If
the water savings from these BMPs can be used to defer capital investments for water supply
192
initiatives, the benefit-cost ratios increase for all the BMPs, and even synthetic turf has a positive
benefit-cost ratio under these circumstances.
193
References:
Babich, H, D L Davis, and G Stotzky. 1981. “Dibromochloropropane (DBCP): a Review.” The
Science of the Total Environment 17 (3) (March): 207–221.
California Urban Water Conservation Council (CUWCC). Best Management Practices Report
Filing. Web. 5 August 2010. http://bmp.cuwcc.org/bmp/read_only/list.lasso
California Urban Water Conservation Council. 2006. Water Utility Direct Avoided Costs Model.
Available at: http://www.cuwcc.org/resource-center/technical-resources/bmp-tools/directutility-ac-eb-models.aspx
Cucamonga Valley Water District (CVWD) (2005) Urban Water Management Plan (UWMP).
Rancho Cucamonga. Available at http://www.cvwdwater.com/index.aspx?page=54
Cucamonga Valley Water District (CVWD) (2009) Comprehensive Annual Financial Report
(CAFR) FY 2009. Rancho Cucamonga. Available at
http://www.cvwdwater.com/index.aspx?page=135
Cucamonga Valley Water District (CVWD) (2011a) Comprehensive Annual Financial Report
(CAFR) FY 2011. Rancho Cucamonga. Available at
http://www.cvwdwater.com/index.aspx?page=135
Cucamonga Valley Water District (CVWD) (2010a) Ordinance No. 30-G: Fees, Rates, Rules and
Regulations for Water Services.
Cucamonga Valley Water District (CVWD) (2010b) Ordinance No. 2010 – 4-2: An Ordinance of
the Cucamonga Valley Water District Establishing Rates and Charges for Recycled
Water Services.
Cucamonga Valley Water District. (CVWD) (2011b) Annual Operating & Capital Improvement
Budget FY 2011. Rancho Cucamonga. Available at
www.cvwdwater.com/Modules/ShowDocument.aspx?documentid=856
Cucamonga Valley Water District (CVWD) (2011c) Urban Water Management Plan (UWMP).
Rancho Cucamonga. Available at
http://www.cvwdwater.com/Modules/ShowDocument.aspx?documentid=1399
Cucamonga Valley Water District. Annual Operating & Capital Improvement Budget (Budget)
FY 2012.
http://www.cvwdwater.com/index.aspx?page=134
Cucamonga Valley Water District. “Conservation.”
http://www.cvwdwater.com/index.aspx?page=59
Inland Empire Utilities Agency. 2009. Annual Water Conservation Programs Report FY 20092010 (Conservation)
http://www.ieua.org/news_reports/docs/2010/Reports_Presentaions/FY09_10_AnnualWa
terC onservationProgramsReport/index.html
Inland Empire Utilities Agency (IEUA). 2010a. Water Use Efficiency Business Plan, Chino.
Available at http://www.ieua.org/news_reports/reports.html
Inland Empire Utilities Agency (IEUA). 2011. FY 2010 – 2011 Regional Water Use Efficiency
Program annual Report, IEUA, Chino. Available at
http://www.ieua.org/news_reports/reports.html
Moody’s Investors Service (2011) New Issue: Moody's assigns aa3 rating to Cucamonga Valley
Water District's water revenue bonds. (Moody’s Ratings).
194
http://www.moodys.com/research/MOODYS-ASSIGNS-Aa3-RATING-TOCUCAMONGA-VALLEY-WATER-DISTRICTS-WATER-New-Issue--NIR_16966426
Los Angeles Department of Water and Power. Securing L.A.’s Water Supply. 2008. (Securing
LA’s Water Supply) http://www.ladwp.com/ladwp/cms/ladwp010587.pdf
Los Angeles Department of Water and Power. Urban Water Management Plan. 2010. (2010
UWMP) http://www.ladwp.com/ladwp/cms/ladwp014334.pdf
Los Angeles Department of Water and Power. Water System Ten-Year Capital Improvement
Program. 2010. (Water System Capital Improvements Program).
http://www.ladifferentiated.com/wpcontent/uploads/2011/02/DWP_Water_System_10Y_Capital_Improvement_Program.pdf
RAND. 2008. Estimating the Value of Water-Use Efficiency in the Intermountain West.
(RAND)
Standard and Poor’s Ratings Services (2011) Issue. (S&P Ratings). 2011.
http://www.standardandpoors.com/ratings/public-finance/ratingslist/en/us/?entityID=290993&issueID=34850992
State of California, Department of Finance (DOF) (2011) E-4 Population Estimates for Cities,
Counties and the State, 2001-2010, with 2000 & 2010 Census Counts, Sacramento,
California, September 2011, available at
http://www.dof.ca.gov/research/demographic/reports/estimates/e-4/2001-10/view.php,
downloaded on June 10th 2012
195
Appendix 1. LADWP Data on Conservation Measures
The LADWP’s UWMP provides specific data on four on the district’s residential conservation
measures, high-efficiency toilets, high-efficiency washers, sprinklerhead rotating nozzles, and
weather-based irrigation controllers (2010 UWMP Chapter Three—Water Conservation) . For
each measure data is given on the value of the rebate given by LADWP, the number of units
installed, and the estimated AF per year water savings. Further, a report by the Pacific Institute
on urban water conservation in California gives the average lifespans of each conservation
measure (Waste Not, Want Not). The data for residential measures is displayed in Table X:
Conservation Measure
High-Efficiency Toilets
High-Efficiency Washers
Sprinklerhead
Rotating Nozzle
Weather-Based
Irrigation Controllers
Year
Costs (Rebate) Units Installed AF Year Savings Lifespan Total Cost Cost Per AF
2009-2010
100
1900
80
20
190,000
118.75
2009-2010
300
66,100
386
12 3,540,000
801.63
2009-2010
8
2878
12.7
10
23,024
22.66
2009-2010
200
81
6.2
20
16,200
130.64
LADWP’s total cost for each measure is found by multiplying the rebate amount by the number
of units installed. Each measure’s costs per AF is found by dividing the total cost by the AF year
savings times the lifespan of the measure. For example, for high-efficiency toilets, the total cost
of 190,000 is divided by the AF year savings of 80 times the lifespan of 20 years:
190,000/(80*20) = 118.75
The same methodology is used the costs per AF of the LADWP’s commercial water conservation
measures, Table X:
Conservation Measure
High Efficiency Toilets
Zero and Ultra
Low Water Urinals
Weather Based
Irrigation Controllers
Rotating Nozzles
for Pop-up Spray Heads
High Efficiency Spray
Nozzles for Large
Rotary Sprinklers
Year
Costs (Rebate) Units Installed AF Year Savings Lifespan Total Cost Cost Per AF
2007-2010
150
58,432
2,408.60
20 8,764,800
181.95
2007-2010
500
58,432
2,408.60
2007-2010
50
391
127.1
20
19,550
7.69
2007-2010
8
22,534
99.1
10
180,272
181.91
2007-2010
13
8,558
308.1
10
111,254
36.11
196
20 29,216,000
606.49
Appendix 2 LADWP Data displaying the estimated future cost of conservation measures
based on a 2 percent inflation rate
Inflation Rate
year
n
Residential
High Efficiency Toilets
High Efficiency
Clothes Washers
Rotating Nozzles for
Pop-up Spray Heads
Weather Based
Irrigation Controllers
Commercial
High Efficiency Toilets
Waterless Urinals
Weather Based
Irrigation Controllers
Rotating Nozzles for
Pop-up Spray Heads
High Efficiency Spray
Nozzles for Large Rotary
Sprinklers
2%
2010
0
118.75
2011
1
2012
2
2013
3
2014
4
2015
5
2016
6
2017
7
2018
8
2019
9
2020
10
121.125 123.5475 126.0185 128.5388 131.1096 133.7318 136.4064 139.1346 141.9172 144.7556
801.63 817.6626 834.0159 850.6962 867.7101 885.0643 902.7656 920.8209 939.2373 958.0221 977.1825
22.66
23.1132 23.57546 24.04697 24.52791 25.01847 25.51884 26.02922
26.5498
27.0808 27.62241
130.64 133.2528 135.9179 138.6362 141.4089 144.2371 147.1219 150.0643 153.0656 156.1269 159.2494
181.95 185.589 189.3008 193.0868 196.9485 200.8875 204.9053 209.0034 213.1834 217.4471 221.796
606.49 618.6198 630.9922 643.612 656.4843 669.614 683.0062 696.6664 710.5997 724.8117 739.3079
7.69
7.8438 8.000676
8.16069 8.323903 8.490381 8.660189 8.833393 9.010061 9.190262 9.374067
181.91 185.5482 189.2592 193.0443 196.9052 200.8433 204.8602 208.9574 213.1366 217.3993 221.7473
36.11
36.8322 37.56884 38.32022 39.08663 39.86836 40.66572 41.47904 42.30862 43.15479 44.01789
Appendix 3 LADWP Data used in benefit-cost analysis
2010
High Efficiency Toilets
High EfficiencyClothes Washers
Rotating Nozzles for Pop-up Spray
Heads
Weather Based Irrigation Controllers
Commercial
High Efficiency Toilets
Waterless Urinals
Weather Based Irrigation Controllers
Rotating Nozzles for Pop-up Spray
Heads
197
Avoided Costs
2015 2010
118.75
801.63
131.1096
885.0643
22.66
130.64
25.01847
144.2371
181.95
606.49
7.69
200.8875
669.614
8.490381
181.91
200.8433
561
1375
Appendix 4: CVWD Operating expenses
(Budget pg. 57)
198
Appendix 5: CVWD Total water supplied
Source: CVWD, 2011 (pg. 71)
199
Appendix 6: CVWD Water production by source
(Budget pg. 18)
Appendix 7: CVWD Residential water conservation measures data, costs per acre foot per
year
residential
year
2004
High Efficiency Toilets
Ultra Low Flush Toilets
Rotating Nozzles for Pop-up Spray
Heads
High Efficiency Clothes Washers
268.1
Weather Based Irrigation
Controllers
Synthetic turf
IEUA Multi-Family Direct Install
Prog.
135.4
*interpolated (Conservation Section 6)
2005
268.1
237.8
200
2006
268.1
237.8
2007
311.7
86.46
2008
2009
194.8 194.11
79.15 70.48
2010
100
200
277.0
200
265.7
200
265.7
300
386.6
73.8
438.0
24.6
428.5
22.8
535.6
223.0
272*
322.4
243.5
Appendix 8: CVWD Commercial water conservation measures data, costs per acre foot per
year
Commercial
year
High Efficiency
Toilets
Waterless Urinals
Weather Based
Irrigation Controllers
ULFT Tank
Rotating Nozzles for
Pop-up Spray Heads
*interpolated
2004
2005
2006
2007
2008
2009
2010
163.3
92.5
163.0
78.9
163.0
352.9
163.0
193.8
205.
78.9
271.8
200*
200
(Conservation Section 6)
Appendix 9: CVWD Average costs data
residential
CVWD Average
Cost per Acre-Foot ($)
Ultra Low Flush Toilets
High Efficiency Toilets
High Efficiency Clothes Washers
Rotating Nozzles for Pop-up Spray
Heads
Weather Based Irrigation
Controllers
Synthetic turf
IEUA Multi-Family Direct Install
Prog.
IEUA Average Cost
per Acre-Foot ($)
78.7
200.2
285.6
135
293
307
225
208
40.4
467.4
81
468
233.3
Commercial
High Efficiency Toilets
Waterless Urinals
Weather Based
Irrigation Controllers
Rotating Nozzles for
Pop-up Spray Heads
Source: IEUA 2009
201
289.7
163.0
423
195
223.8
173
200
208
Appendix 10: CVWD Future costs of conservation measures calculations
Inflation Rate
year
n
Residential
Ultra Low Flush Toilets
High Efficiency Toilets
High Efficiency
Clothes Washers
Rotating Nozzles for
Pop-up Spray Heads
Weather Based
Irrigation Controllers
Synthetic turf
IEUA Multi-Family
Direct
Install Prog.
Commercial
High Efficiency Toilets
Waterless Urinals
Weather Based
Irrigation Controllers
Rotating Nozzles for
Pop-up Spray Heads
2%
2010
0
2011
1
2012
2
2013
3
2014
4
2015
5
2016
6
2017
7
2018
8
2019
9
2020
10
78.70292 80.27697 81.88251 83.52016 85.19057 86.89438 88.63227 90.40491 92.21301 94.05727 95.93842
200.1765
204.18 208.2636 212.4289 216.6774 221.011 225.4312 229.9398 234.5386 239.2294 244.014
285.6314
291.344 297.1709 303.1143 309.1766 315.3601 321.6673 328.1007 334.6627
225
229.5
341.356 348.1831
234.09 238.7718 243.5472 248.4182 253.3865 258.4543 263.6234 268.8958 274.2737
40.42491 41.23341 42.05807 42.89924 43.75722 44.63237 45.52501 46.43551 47.36422 48.31151 49.27774
467.4102 476.7584 486.2936 496.0195 505.9399 516.0587 526.3798 536.9074 547.6456 558.5985 569.7705
233.2976 237.9636 242.7229 247.5773 252.5289 257.5794
262.731 267.9857 273.3454 278.8123 284.3885
289.7159 295.5102 301.4204 307.4488 313.5978 319.8697 326.2671 332.7925 339.4483 346.2373 353.162
162.9987 166.2587 169.5839 172.9756 176.4351 179.9638 183.563 187.2343 190.979 194.7986 198.6945
223.8284 228.3049
200
204
232.871 237.5284
242.279 247.1246 252.0671 257.1084 262.2506 267.4956 272.8455
208.08 212.2416 216.4864 220.8162 225.2325 229.7371 234.3319 239.0185 243.7989
(Conservation Section 6)
Appendix 11: CVWD Data used for benefit-cost analysis
78.7
200.2
285.6
Avoided
Avoided
Costs
Costs 2015
2015 2010
449
606
86.9
221.0
315.4
225
40.4
467.4
248.4
44.6
516.0
233.3
257.6
289.7
163.0
223.8
319.9
180.0
247.1
200.0
220.8
2010
Ultra Low Flush Toilets
High Efficiency Toilets
High Efficiency Clothes Washers
Rotating Nozzles for Pop-up Spray
Heads
Weather Based Irrigation Controllers
Synthetic turf
IEUA Multi-Family Direct Install
Prog.
Commercial
High Efficiency Toilets
Waterless Urinals
Weather Based Irrigation Controllers
Rotating Nozzles forPop-up Spray
Heads
202