Grand Junction Retrofit SOW

• Project Type: General OWC
• Applicant: City of Grand Junction
• Project Name: Residential Retrofit Project
• Title: Project Plan
• County: Mesa
• Water Conservation - Doc Type: Complete Plan

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PROJECT IMPLEMENTATION
1. Residential Participation - A sample size of 96 single family
homes was determined a~'a minimum number for participation. The
size was calculated wIth 95% confidence that the sample size water
use average varies no more than 10% from the population water use
average, This level of confidence is for sample size determination
only and not to be confused with the confidence in data analysis.

Methodology - A request for project participation will be mailed to
1,000 single family customers to ensure that responses are adequate
to reach the desired sample size, Typical survey responses fall in
the range of 12-15% returns, Assuming a similar response, the
desired sample size should be easy to achieve from a mailing to
1000 customers.

A random sample of 1,000 single family customers will be generated
from the Grand Junction computerized billing records. The mailing
will specify criteria that all households are to meet and also
point out savings benefits from participation. criteria required of
participating homes will include (1) home ownership (2) consent to
have utility bills monitored (3) agreement to install devices in
all fixtures for duration of study. (Program request letter
developed by DNR),

Responses for participation may potentially exceed the necessary 96
households, If this happens, a decision will be made whether to
include all respondents or to set a cut-off point. If all
respondents are not included, the extra households will be supplied
with a variety of water conservation information items to keep
their interest,

Homeowners agreeing to participate in the project may be
predisposed to water efficient habits and therefore skew the
results, To determine if there are any differences between the
participants and households that do not respond, a survey will be
conducted from a random sample of the non-responding households.
The survey will collect general household information and attempt
to determine existing water use habits,

2, Project Devices - The devices for project use will be the
Future Flush, a dual flush toilet device, the ShowerSpa 2000
showerhead, and a faucet aerator, These devices will help provide
information on the effects of both energy and water usage.

Donations will be made from Con-Tech Industries, manufacturers of
Future Flush, and Energy Technology Laboratories, manufacturers of
the ShowerSpa 2000 and aerator, The donation of devices assumes 70%
of the sample homes will have two bathrooms and all will be
retrofitted with both devices. Devices will be delivered to Grand
Junction when a total count of needed fixtures is determined.