Studies and Reports

The Strategic Plan provides a blueprint for meeting Valley Water’s established conservation policy objectives. It serves as a tool and reference document to inform and support Valley Water’s future conservation program marketing and design. The Plan finds that Valley Water will be able to meet its long-term conservation targets with continued implementation of its current broad set of conservation programs, but doing so will require increased customer participation and a commensurate increase in staff resources and funding. It is also recommended that Valley Water explore additional opportunities to augment and adapt its current programs.

This study shows that turf removal and irrigation equipment rebate programs can be successful in achieving water conservation goals, and describes factors that may contribute to program success. The study focused on single-family residences, which comprise the largest Landscape Rebate Program participant type. Water use up to three years prior to installation of a new landscape or irrigation equipment was compared to water use after installation, for a period up to five years. 

• The average water savings for converting turf area to a landscape of low-water use species in conjunction with drip irrigation incrementally increased each year following conversion: saving on average, 31 gallons per square foot per year (gal/ft2/yr) for years 2 to 5, and saving 48 gal/ft2/yr during the fifth year following conversion.
• The annual water savings for replacing timer-based automatic irrigation controllers with weather-based irrigation controllers with rain shut-off devices were statistically significant each year following conversion, incrementally increased each year following conversion, and were on average 9 gal/ft2/yr.
• The annual water savings for replacing old sprinklers with high-efficiency nozzles were 1,243 gal/unit/yr on average.
• Annual savings for replacing old sprinklers with high-efficiency nozzles including pressure regulation and/or check valves were significant in the first year following conversion, saving 1,661 gal/unit/yr on average. 

(The above content was paraphrased from the study's Abstract within this document. Additional details, figures, and analyses are found within the full study.)

This study shows that turf removal and irrigation equipment rebate programs can be successful in achieving water conservation goals, and describes factors that may contribute to program success. The study focused on single-family residences, which comprise the largest Landscape Rebate Program participant type. Water use up to three years prior to installation of a new landscape or irrigation equipment was compared to water use after installation, for a period up to five years.

• The average water savings for converting turf area to a landscape of low-water use species in conjunction with drip irrigation incrementally increased each year following conversion: saving on average, 31 gallons per square foot per year (gal/ft2/yr) for years 2 to 5, and saving 48 gal/ft2/yr during the fifth year following conversion.
• The annual water savings for replacing timer-based automatic irrigation controllers with weather-based irrigation controllers with rain shut-off devices were statistically significant each year following conversion, incrementally increased each year following conversion, and were on average 9 gal/ft2/yr.
• The annual water savings for replacing old sprinklers with high-efficiency nozzles were 1,243 gal/unit/yr on average.
• Annual savings for replacing old sprinklers with high-efficiency nozzles including pressure regulation and/or check valves were significant in the first year following conversion, saving 1,661 gal/unit/yr on average.

(The above content was paraphrased from the study's Abstract within this document. Additional details, figures, and analyses are found within the full study.)