Greywater Can Save Water

Let’s face it. Most of us can’t do much of anything about where we get our municipal water. However, we can do quite a bit about how much we use. By recycling some of the water used in their homes, called greywater, some homeowners in north-central California cut their water use by an average of 26 percent, according to a 2013 study by Greywater Action. Greywater is used water from bathroom sinks, tubs and washing machines. One writer described it as gently used. Greywater recycling systems collect at least some of this water for landscape irrigation or flushing the toilet. Collection is as simple as sticking a bucket in the shower or as complex as the NEXtreater, an installed system that washes greywater, sends it through two filters and a UV light and stores it so it comes out looking and smelling like tap water. The three most common types of greywater collections systems are laundry-to-landscape, branched drain, and pumped, according to Greywater Action. Laundry-to-landscape is the easiest and least expensive. In fact, plans and directions are free online. It simply takes water from the washing machine and, using the washing machine pump, sends it outside. Branched drain also takes water from sinks and showers and does the same thing. Both go out to a mulch basin, basically a hole in the ground filled with wood chips, and out to plants. A pump system takes greywater, stores it in a tank and pumps it to where you want it. Greywater pipes are separate from pipes that go to sewage. Greywater Action’s study found that laundry-to-landscape systems can cost $250 to $2,000, depending on installation and permit costs (in some states, no permit is necessary). Branched drain systems cost from $400 to $3,000, pumped systems cost $600 to $3,000 and high-tech systems like the NEXtreater that filter and clean water can cost $5,000 to $10,000. Homes can be retrofitted for greywater recycling, said Ralph Petroff, Executive chairman of Nexus eWater, the company that makes the NEXtreater. “We think that, nationally, maybe 50 percent of the homes could do a full-house gray-water retrofit relatively inexpensively, and the other 50 percent would be either challenging or you could do a partial retrofit,” he said in an interview with Water Deeply. Greywater can’t be used for everything, according to greywateraction.org. For example, the water shouldn’t touch the edible parts of garden plants. Therefore, a drip irrigation system is necessary and greywater isn’t for root crops like carrots. Greywater should not pool or create runoff and, unless it’s a high tech system, should be used the day it’s produced so it doesn’t start to stink. It shouldn’t be touched or ingested. A system needs valves so greywater can’t backwash into regular water. Normal laundry detergent won’t work with greywater either. It contains salts and boron that accumulate in soil. A story in Mother Earth News said boron levels in detergent should be below 0.1 mg per liter and sodium below 40 mg per liter, which is about as much as in some tap water. Detergent shouldn’t contain bleach. Most bath products are OK because they’re used in such small amounts, according to Mother Earth News. Greywater codes differ between states. Look for them in the state’s plumbing codes in its building department or in its environmental health department, Laura Allen wrote in “The Water Wise Home: How to Conserve, Capture, and Reuse Water in Your Home and Landscape.” “Florida bans outdoor greywater use but allows it for flushing toilets. Georgia allows you to carry greywater in buckets to the plants, but you can’t get a permit to build a simple greywater irrigation system. Washington State’s code allows very small systems built without a permit (following performance guidelines), but all other systems have quite stringent requirements. Oregon requires an annual permit fee,” Allen wrote. Even though greywater can come with difficulty, using it could produce extraordinary water savings, according to waternow.com. “If just 10 percent of California’s 12 million+ households captured and reused greywater, the state could save 373,000 acre-feet annually. Just for comparison: The Hetch Hetchy Reservoir holds about 300,000 acre-feet. The proposed expansion of Shasta Reservoir would yield about 76,000 acre-feet annually,” according to its California Graywater Factsheet. How are you recycling your water?