Water Conservation Alliance of Southern Arizona
Resedential Graywater Reuse Study
In arid regions of the U.S., water conservation and reuse are issues that receive a great deal of public attention. The search for ways to responsibly use and reuse water is vital to the sustainability of the water supply and thus the future of these areas. Wastewater treatment and reuse is one of the best water conservation options available to communities located in arid areas. Many large scale reuse efforts have been developed, such as the watering of golf courses with treated municipal effluent or the use of effluent for groundwater recharge (Asano, 1998). But the potential for wastewater reuse is not limited to large-scale projects supplied by community wastewater treatment facilities. It is also available to individual homeowners. Graywater recycling offers a way in which people can save and reuse the wastewater generated in their own home.
To add to the understanding of and clarify the issues surrounding the safe and effective use of household graywater, in 1998 the Water Conservation Alliance of Southern Arizona began an in depth study of residential graywater reuse in the greater Tucson area. The study, supported by the Arizona Department of Water Resources, the Arizona Department of Environmental Quality, the Pima County Department of Environmental Quality, looked at two separate aspects of graywater usage in the area: 1) the number of households currently using some portion of the graywater they generate and 2) the water quality of the residential graywater being generated and how that water quality affects the soil that is irrigated with that water. What follows are the results of this study.
Summary of Findings PDF (166k)
Water Quality Data PDF format (104k)
- Initial Water Quality Testing
- BOD Test Results:
Site 1 Site
2Site 5 Site 6 Site 7 Site 10 Site 13 Site 14 Site 17 Site 18 Site 19 Sampling Round 7 58. * >48. ** <44. * NS 48. * NS NS NS 66 NS 244. * Sampling Round 8 80 386 <44. NS 50 69 98 379 119 65 <44 * - The oxygen depletion for the BOD seed was outside laboratory acceptance criteria. The associated GGA check standard was acceptable. Data is considered valid.
** - Value reported as "greater than" due to missed dilution. Bolin set up BOD dilutions according to sample appearance since no history was available.
- Data by Site:
Site 1 sampling results
Site 2 sampling results
Site 5 sampling results
Site 6 sampling results
Site 7 sampling results
Site 10 sampling results
Site 13 sampling results
Site 14 sampling results
Site 17 sampling results
Site 18 sampling results
Site 19 sampling results
Site 40 sampling results
Site 40B sampling results
- Data By Sampling Round
- Graphically Conveyed Sampling Data
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