Gray Water

How Does it Work?

Ideally, a seperate set of pipes will be installed for a graywater system. Water from toilets and kitchen sinks will go into the sewer/septic system. Water from all other sources will go into a basic filtration system to removce particles. From that point, the water can can flow back to fill toilet bowls or in a sub-irrigation system to water lawns or trees. Systems, either home-built or professionally made, are started to be approved and installed around Montana since becomimg legal in late 2007.

 

Legal Status

In Montana's history, gray water systems used to be fairly common. Many old ranchouses have gray water systems as a common sense conservation measure. In recent history, gray water was illegal in Montana until the 2007 Legislative, where S.A.V.E. helped to make this conservation solution legal. Read more about this success story on our blog.

Since that time, the Montana Department of Environmental Quality has established a rule making task force, where the S.A.V.E. Foundation has also been involved. "The gray water legislation from this and last session, is a tribute to the legislative process that has brought forth a great opportunity to conserve water," said Matt Elsaesser, S.A.V.E.'s Director. "As the rule making goes forth, we now hope Montanans from across the state get engaged as well," he added.

During the 2009 Legislative Session another major step was taken for expanding the use of gray water systems across Montana. Amid concerns that current laws were too restrictive, House Bill 285 lifted the limitation that only single homes may install gray water systems. It was sponsored by Rep. Michelle Reinhart (D-Missoula). Many legislators hoped to use the expanded law to engage a broader coalition of builders, pumpers, architects, and homeowners to ensure good rules for gray water systems follow the law. Now a law, this expands the use of simple technology for water recycling into multi-family homes and commercial buildings.

From Top (L-R) Kent Schlosser, Ross Phillips, Taylor Lyon, Tyler Evilsizer, Jack Isbell, and Matt Elsaesser. Bottom: Kim Degner, Governor Schweitzer, and Representative Michele Reinhart for signing of HB 285.

Gray water not only saves water, but provides nutrient rich water that is excellent for shrubs and trees because it is high in potassium and phosphorous-providing the added benefit of redirecting some nutrients (used by plants rather than lost downstream). A system can be as simple as a filter and a design to ensure that water is used within around 24 hours. More complex systems can include additional treatment like added chlorine if the gray water will be used to flush toilet bowls. Usually these systems are installed in new construction or during major renovation since they require additional plumbing to keep the gray water separate. Since the passage of HB 259 in 2007, at least two model systems have been installed in Helena and Bozeman.

Links

Recent News in Montana:

Gray Water Law is a Good Step Forward Montana Standard, April 1st, 2009

S.A.V.E. featured on Billings station *Excellent synopsis of gray water, January 2008,

Gray water may help stretch precious resource Butte Montana Standard, December 2007, also in Billings Gazette

New law helping conserve Montana's water Montana's News Station, November 2007

Other Info:

Wikipedia Article - Excellent overview of Gray Water

Greywater.com - Includes basic diagrams

Gray Water Policy Center - A collection of other state and national laws regarding gray water.