Sustainable Facilities Tool General Services Administration

Leadership in Environmental and Energy Design (LEED) for Building Operations and Maintenance (O+M) dedicates certification credits to reducing the burden on potable water supply and wastewater systems through implementation of water-conserving indoor plumbing fixtures and fittings that meet or exceed the Uniform Plumbing Code (UPC) or International Plumbing Code (IPC). Metering of irrigation, indoor plumbing fixtures, cooling towers, domestic hot water, reclaimed water, and other process water uses is emphasized. Reducing the water demand for irrigation and indoor plumbing fixtures through water-efficient landscaping and fittings respectfully, is also explicit in LEED O+M. In addition, credits are available for utilizing non potable water sources in cooling tower makeup water use.

LEED for Interior Design & Construction (ID+C): Commercial Interiors employs a number of sustainable water system best practices in its certification process. A twenty percent reduction in overall building water use compared to the tenant space baseline is required, while reductions between twenty-five and fifty percent are rewarded with more credit points. LEED ID+C guidance recommends using WaterSense-certified fixtures coupled with using alternate on-site sources of water such as rainwater, stormwater, greywater, and air conditioner condensate. Commissioning the domestic hot water systems is made explicit as part of the whole building commissioning process.

Leadership in Environmental and Energy Design (LEED) for Building Design and Construction (BD+C) addresses components of a sustainable water system in a number of ways. Projects are required to employ strategies that in aggregate use twenty percent less water than the building's plumbing fixture water use baseline. Integrating water-efficient landscaping that reduces potable water consumption by 50 to 100 percent is also identified. Additionally, reducing the quantity of potable water use for building sewage conveyance or treating wastewater on-site assists in achieving project certification.

A sustainable water system is directly addressed in Green Globes New Construction certification system in the categories of project management, site, and water. Water performance goals can be set between 10-35 gallons/ft²/year, with credit given to ongoing performance verification and documentation. Sub-metering is rewarded, as well a minimal use of water for cooling towers. Outdoor water use for irrigation is discouraged. Emphasis is further given to implementing on-site wastewater treatment systems where practical.

Green Globes for Existing Buildings encourages cognitive implementation and metering of water heating equipment for energy efficiency measures. With regards to water conservation, high-efficiency toilets and urinals that use less than 1.6 and 1.0 GPF respectfully are made explicit. Green Globes for Existing Buildings rewards thoughtful water management and written policies to discourage the use of once-through cooling units and landscaping necessitating a plentiful water supply while ensuring proper maintenance of the water system is upheld.