CRC_SlowTheFlowPhase2_ImpactAnalysis

• Water Efficiency Grant Type: Public Education & Outreach Grant
• Contract/PO #: OE PDA 07-21
• Applicant: Center for Resource Conservation
• Project Name: Slow the Flow Colorado 2006: Irrigation Audit Program
• Title: Irrigation Inspection Program: Impacts of Slow the Flow Colorado on Outdoor Water Use
• Date: 6/1/2007
• County: Boulder
• Water Efficiency - Doc Type: Interim Reports

Households Watering Below ET Prior to Inspection

Difference ofPre-Atdt and Post-Audt onhor ~r !.Sage of2005AG<EI
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15%
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Roughly 1/3 of properties were watering below ET prior to the inspection. As can be
expected from this group, since they were already watering below ET, we did not see a
reduction in water use. The trend was to water closer to actual ET rates, resulting in
healthier landscapes and more efficient water use.

*The results for each city may vary, but that the overall trends can be seen in the majority
of the communities analyzed. Additionally, due to the small sample sizes of some cities,
data is not as reliable as when included in the larger sample.
Appendix I: 2005 Results by City

Conclusions
Due to the different behaviors of the pre-inspection groups (households watering above
or below ET) it was very difficult to quantify the differences between the means for the
population as a whole. It was more informative to 1001< at the pre-inspection groups
separately.

When comparing the watering habits of properties that were watering above ET prior to
the inspection with their watering habits after the inspection, a statistically significant
reduction in water usage was observed. Results showed that in 2004 75% of participants
that watered at rates above ET prior to the inspection reduced their water usage after the
inspection. In 2005,79% of participants that watered at rates above ET prior to the
inspection reduced their water usage after the inspection.

When comparing the watering habits of properties that were watering below ET prior to
the inspection with their watering habits after the inspection, the trend was to use more
water. However, these properties still watered either at or below the ET rates.

30