AWWA SOURCES55625

The City of Chula Vista is poised at the threshold of a growth spurt, with a large number of residential development proposals in the pipeline, to meet the expected demand for additional housing. It is projected that by 2020, an additional 10,000 housing units will be built in the City. Since over 90 percent of the City of Chula Vista's water supplies are imported from other basins, planners saw the need for incorporating as much water conserving features into new homes as technically and economically feasible. An economic analysis was conducted comparing 14 specific water conservation options, their characteristics, costs, benefits, and feasibility of implementation during the construction stage. The 14 options are above and beyond those already mandated either by federal, state, or local regulations in effect, such as ultra low flush toilets (ULFTs), low-flow showerheads, etc. The 14 evaluated options included water-efficient landscapes, xeriscape, evapotranspiration controllers for landscape irrigation, high-efficiency clothes washers, hot-water pipe insulation, water- efficient dishwashers, hot-water demand units, dual-flush toilets, pressure-reducing valves, use of recycled water for landscape irrigation, and use of gray water systems for onsite water reuse. Typical water savings data for each of these options were obtained from the literature on a unit (per-residence) annual basis. Costs were obtained from manufacturers, builders, and suppliers of systems. Present-worth value of the water savings over the life-cycle of each conservation option was calculated, as was cost of purchase and operation, maintenance, and administration. From these analyses, benefit-cost ratios were calculated for side-by-side comparison of a diverse range of water-use- efficiency options. The process used in this study can provide a rational basis for encouraging sustained future water use efficiency in new developments. It also can serve as a model for other communities desiring to build water conservation options into new homes built for their own growing housing needs. Includes tables, figures.

Product Details

Edition:

Vol. - No.

Published:

01/01/2002

Number of Pages:

19

File Size:

1 file , 440 KB