Electricity, natural gas, and water flowing into buildings through utility connections, and wastewater and exhaust gases flowing out of buildings, are some of the most tangible links to understanding a building’s environmental impact. Paying more attention to these flows can lead to big reductions in resources consumed and pollutants sent downstream.
Division 33 includes metering and submetering equipment for water and natural gas—electrical metering is covered in Division 26: Electrical. Targeted metering of energy and water consumption is an important first step toward reducing usage.
Also included are rainwater harvesting and storage equipment. Rainwater harvesting systems can offset, and in some cases eliminate, a building’s reliance on conventional sources of potable water. A variety of cisterns and tanks, as well as filtration and first-flush systems, are available for in sizes ranging from tens to thousands of gallons. These systems also reduce rainwater runoff by capturing and storing rainwater onsite.
Other systems that detain, direct, control and treat stormwater are also covered here. These systems protect downstream environments from pollutants carried by stormwater from parking lots and other paved areas to surface water during rain events. They can also help avert downstream flooding and increase aquifer recharge. Infiltration trenches, porous pavement, and bio-filtration systems are lower maintenance options that should be considered whenever possible—those are listed under Exterior Improvements.
Reducing reliance on centralized sewage systems that use water to move waste from buildings to energy-intensive treatment facilities saves both water and energy. GreenSpec lists a number of onsite treatment options suitable for neighborhoods or large facilities. In addition to water and energy savings, these systems allow for innovative onsite reuse of treated water as well as nutrient recovery from the waste stream. Another option to consider for achieving these energy and water savings are composting toilets and graywater systems, listed in Plumbing.