LEED® Certification for New Construction – Water Efficiency

January 22, 2009  /  Lifestyle

According to the U.S. Environmental Protection Agency, an American family of four can use 400 gallons of water per day.  About 30% is used outdoors for watering lawns and gardens, washing automobiles, cleaning sidewalks and driveways and maintaining swimming pools.Nationally, landscape irrigation counts for almost one-third of all residential water use.  That’s more than 7 billion gallons per day.  All of the above facts are contributing factors to the addition of water efficiency credits for LEED® certification.There are five points available for water efficiency:•    Water efficient landscaping (2 pt)o    Reduce by 50% (1 pt)o    No potable use or no irrigation (1 pt)•    Innovative wastewater technologies (1 pt)•    Water use reduction (2 pt)o    (20%)o    (30%)Many of these credits deal with Graywater and Blackwater.  Graywater is untreated wastewater such as shower water, water from sinks (other than the kitchen), bathtubs and clothes washers.  Blackwater is generally defined as toilet, urinal and kitchen sink water.Water Efficient LandscapingThe purpose of water efficient landscaping is to reduce (by at least 50%) or eliminate the amount of drinking water and natural surfaces used for landscape irrigation.  There are several ways to do this, including:•    Using a high efficiency micro-irrigation system, such as drip, micro misters and subsurface irrigation systems.•    Using captured rainwater, recycled wastewater or treated water instead of drinking water•    Using treated water from a public agency that is specifically used for purposes other than drinking.Innovative Wastewater TechnologiesHere, the builder is expected to reduce wastewater generation and potable water demand, and increase the recharge of local aquifers.  You can reduce potable water demand by using water conserving fixtures, reusing non-drinking water for flushing or reuse water treated on-site.  If you use the last, the water must be treated by biological systems, constructed wetlands or a high efficiency filtration system.Water Use ReductionReduction of water usage can be achieved by using special fixtures and sensor/metering controls.  You can also reuse storm water and Graywater for non-drinking purposes.  For extra credits, you can reach for a 40% reduction.If you need help figuring out how to calculate water usage and reduction, there is a tutorial here

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  1. Arianacike

    I am very interested in this

    May 13, 2009

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