Audit of Major Commercial & Irrigation Water Accounts

• Project Type: General OWC
• Applicant: Town of Castle Rock
• Project Name: Commercial & Irrigation Water Audit
• Title: Audit of Major Commerical and Irrigation Water Accounts
• Date: 6/29/2006
• County: Douglas
• Water Conservation - Doc Type: Final Report

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Audits of Major Commercial and Irrigation Water Accounts
Town of Castle Rock

flow toilets and urinals, automatic flush fixtures and automatic lavatories. The kitchen
was not available for inspection during the site visit.

Average water usage at the facility is linked to customer visits, which were up in 2005
due to the placement of Chili's on the 1-25 public service signage advertising the
restaurant. The restaurant receives publicity via this vehicle on a rotating basis, one year
out of three. Water usage is expected to drop as soon as Chili's is taken offthe signage in
favor of another local establishment. This advertising explains the upward trend in water
use experienced at Chili's over the two year period analyzed (see Attachment 4). Based
on the customer visit information made available at the time of the site visit, all of which
was for wintertime months, an average customer uses slightly more than 9 gallons of
water per visit.

Average wintertime usage at Chili's is about 170,000 gallons per month. Summertime
usage is about 30% above average wintertime usage (see Attachment 4). This increase in
summertime usage is presumably associated with the irrigation of about 0.5 acres of
landscape on the property. As can be seen in Attachment 5, which compares the actual
irrigation to eighty percent of the estimated monthly ET for each summer month in the
past two years, the irrigation of this landscape was performed more efficiently in 2004
than 2005. The observed irrigation patterns in these two years is indicative of a spray
irrigation system augmented with a precipitation sensor, since 2004 was substantially
wetter and cooler than 2005.

Nonetheless, irrigation at Chili's substantially exceeded the target of eighty percent of
ET. In fact for 3 out of 6 summertime months in 2005 Chili's exceeded its irrigation
"budget" by about 110%. For 2004 and 2005, Chili's paid about $2,700 for irrigation
water. If during that same period of time the water budget pricing were in place, Chili's
would have paid over $2,000 more for the same amount of water, or over $4,700.

During the site visit, the manager of Chili's indicated that the organization is looking to
follow suit with other local restaurants that have removed their irrigated landscape in
favor of either hardscape or xeriscape. He had no set time by when this change would
take place, however it appears that the planned change to the Town's water rates will be
one contributing factor.

Alternatives and Recommendations
Chili's already utilizes the state of the science fixtures to manage indoor water use,
therefore their opportunities for improved water use efficiency relate to outdoor water
use. Chili's could reduce water use by improving its irrigation technology and/or its
outdoor landscaping. For example, Chili's could have saved nearly 40 percent of last
summer's outdoor water use if it had an ET Controller properly installed and
programmed. The cost of an ET Controller for 14 zones is about $800 to purchase,
install, and program. This investment would have been paid back to Chili's in one
irrigation season even without water budget pricing.

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