Water the Lawn With Your Saturday Night Bath

Why not divert shower water to the lawn, instead of sending it to the sewer? Plants don't mind a little soap and, well, skin cells. And the savings aren't hard to imagine when you consider that even with all those low-flow fixtures installed, the potable water you lavish on shrubs draws significantly on your fresh-water supply. So does that clean water you tap for flushing, which in some states can be substituted with the effluent from your sink.

Redirecting gray water for such uses isn't always easy. See what expert advice ReWater Systems manufacturer Steve Bilson shares about installation and how much you can save annually.

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Consider three retrofits Bilson approves of:

A. Sink-Fed Toilet Tanks

Flushing toilets with water draining from showers, sinks, and tubs is allowed in International Plumbing Code states (it's prohibited by the Uniform Plumbing Code in 17 others, mostly in the West). This sink-to-toilet tank hookup, from Water Saver Technologies, is a self-contained system: Source water flows via pump directly to its end use. (Source water from a bathroom sink-not a kitchen one, which is at high risk for bacteria such as E. coli-is recommended.)

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B. Laundry-Fed Irrigation

The easiest gray-water source is a washing machine. Its pump is already pulling water out, discharging it into an accessible standpipe that you can extend outside the house. Just take care to strain the water through a sand filter or polyester felt mesh bag, bury irrigating polyethylene pipes 9 inches deep, and keep the discharge far from wells, creeks and streams.

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C. Gray-Water Main Line

To reuse gray water throughout your home, you need a whole-house "gray water supply" main line. It resembles the existing main drain but is separated from toilet lines and leads to a surge tank that's properly vented through the roof. To separate gray sources from the main, you also need a crawl space or basement foundation for easy access to plumbing.

Don't miss all the tips for redirecting gray water to water your lawn at thisoldhouse.com.

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