Proposed measures to improve water efficiency of high-performance, non-low-rise residential buildings include limitations on full-flush volume for toilets and use of municipal reclaimed water for irrigation.
"Measures to improve water efficiency, including limitations on full-flush volume for toilets and use of municipal reclaimed water for irrigation, are being proposed for ANSI/ASHRAE/USGBC/IES Standard 189.1-2011, Standard for the Design of High-Performance, Green Buildings Except Low-Rise Residential Buildings. ..."
"The addendum would limit the full-flush volume for all toilets to 1.28 gal per flush and limit kitchen faucet capacity to 1.8 gpm ..."
"Proposed addendum v also would set limits on the use of municipal reclaimed water for irrigation. Municipal reclaimed water is highly treated, usually to drinking water standards, and often in short supply. Furthermore, the growing use of municipal reclaimed water for groundwater recharge of potable water supplies increases its value. ..."
'“It is unreasonable to allow the unfettered use of reclaimed water, considered a precious resource, as a means to save energy when there are more viable alternatives,” Pape said. “Therefore, the use of municipal reclaimed water would be prohibited for roof-cooling applications and for permanent irrigation of vegetated roofs using either in-ground or above-ground irrigation systems. There are many other alternative water sources that can be used for this puprpose, including graywater, condensate recovery, rainwater and cooling tower discharge.”'