Castle Pines North WC Plan2007

• Project Type: Water Conservation Plan
• Applicant: Castle Pines North Metropolitan District
• Project Name: Water Conservation Plan
• Title: Castle Pines North Metropolitan District Water Conservation Plan
• Date: 8/1/2006
• County: Douglas
• Water Conservation - Doc Type: Complete Plan

CDM

Section 7
Evaluation and Selection of Conservation Measures and Programs

Table 7-3 provides estimated costs for each measurejprogram, an analysis of cost
effectiveness, and net benefits. The first column provides the assumed number of new
units per year (e.g. retrofit or square feet for the Sod Rebate Program). The second
column shows the assumed costs per each unit (e.g. rebate received by a customer for
installing a toilet) while the third column shows the estimated total water savings for
the 10-year (2006 to 2015) planning period. The remaining columns provide
information on the costs associated with implementing conservation measuresj
programs, an analysis of cost effectiveness, and the net benefits of conservation. The
analysis of cost effectiveness compares the cost per 1,000 gallons to produce the water
(pump, treat, and distribute) and the cost per 1,000 gallons to implement the
conservation programj measure. The net benefit analysis provides the costs saved by
conserving water and the net benefit. If the net benefit is negative, the costs for the
conservation program exceed the costs saved in conserving water. Details on how
each of these columns is calculated are provided in the footnotes at the end of the
table.

7.3 Comparison of Benefits and Costs

Table 7-4 consolidates information from Table 7-2 and 7-3. It presents a comparison of
program costs, average annual water savings for the planning period, and net costs
benefits for the evaluated conservation measures and programs. The net benefits are
ranked from the highest benefits to lowest.

The net benefits would likely be substantially higher if surface water supplies are
brought online (assuming surface water is more expensive than groundwater) or if
the cost of groundwater production significantly increases. This is because the cost of
water production would be much higher and consequently there would be greater
cost savings per gallon of water conserved. There would be greater incentive for the
District to conserve water.

As discussed in Section 4.3, groundwater is nonrenewable. The decline of the
groundwater table will eventually cause a substantial increase in the cost of
groundwater pumping. It is important to note that this evaluation does not account
for this increase because the timing of when this will occur can not be accurately
determined. If the District continues to solely rely on groundwater, eventually the
cost to produce the water will increase, providing greater incentive for conservation.

The conservation programs that rank the highest include the following:

. Increasing block rate structure
. District irrigation efficiency for open space
. Sonic Leak Detection Program
. District irrigation efficiency for parks

7-6

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