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When green building expert, Alex Wilson, was getting ready to announce his publication's favorite products of the year, he emphasized his concern that water shortages are looming. When we look at green building and products, we need to not only be aware of energy efficiency, but also water efficiency. Next to petroleum, water is soon to be one of our scarce natural resources and should be carefully preserved as such. 

Low Flow Plumbing Fixtures
According WaterSense, flow rates lavatory faucets must be at 1.5 gallons per minute, showerheads at 2.0 gpm and toilets at 1.28 gallons per flush — many plumbing fixture companies are getting ahead of the game, with super low flow fixtures and touch free technology, which not only reduces water use, it also improves hygiene.

Delta: Over fifty-percent of Delta's faucets and showerhead collection is WaterSense certified, many of which have added features that further improve their water-saving performance. Their H2Okinetic showerhead flows at 1.5gpm while providing the feel of a 2.5gpm flow; Touch2O Technology turns faucets on and off with a simple tap, which reduces unnecessary water flow and minimizes contact with bacteria for a more hygenic experience; Multi-Flow is a toggle option on some kitchen faucets that increases the stream from the standard 1.5gpm to a higher flow when efficiency is not a concern (for example when filling pots, vases or other large containers); the Proximity Sensing Technology forms a 4" field around the body of a faucet for hands-free faucet use.
Caroma: Most dual flush toilets use 0.8gpf for the light flush, and 1.6gpf for the heavy flush, but Caroma's Smart Series of high efficiency toilets (HET) uses only 1.28gpf for the heavy, which averages at around 0.9gpf for total use of the toilets — half the industry standard of 1.6gpf! We of course still love their Profile Smart series — it has an integrated sink at the top of the toilet tank, which drains water from the sink into the tank to be used for the next flush.
Niagra Conservation: We're sure that the couple of times we've already mentioned Niagra's Stealth Toilet won't be the last. This toilet is the most efficient, and lowest water using toilet on the market at 0.8 gallons per flush, which is less than the required maximum of 1.6gpf! Find out how it works and more about the groundbreaking technology at Stealth's website.

Rainwater Reuse
In addition to using less potable water in the home, capturing rainwater is continuing to gain momentum. The majority of products we saw were geared towards rainwater storage, however there were also a few filtration systems for graywater reuse, which unfortunately is still not permitted in all municipalities.

Jay R Smith Mfg. Co.: Jay R Smith has a huge catalog and manufacturers a wide range of drainage and rainwater harvesting systems. At GreenBuild they were demonstrating their commercial and residential rainwater harvesting system, which is set up to be used for storage and potential graywater use. Their system collects rainwater, filters it, and then stores it in an underground tank for landscape and non-potable uses.
Rainwater Pillow: As we featured in our favorite products post, the Rainwater Pillow is a super simple rainwater storage system. Rather than storing rainwater in rigid, inflexible tanks, the Rainwater Pillow is esstentially like a large flexible bladder. The bag can hold between 1,000 to 200,000 gallons of rainwater and can be stored pretty much anywhere you can fit it.

More GreenBuild 2010:

(Images clockwise starting from left: Delta Touch2O; Stealth Toilet; Jay R Smith Mfg. Co.; Delta H2Okinetic)