Thursday, July 9, 2009

Graywater Re-Use

Sorry I have not posted yet today, but I have been buried - in a compost heap of my own. So, as I was eating scraps for lunch... I stumbled on to an article written by Carol Steinberg and it is awesome. I assume since many of you read the drivel I write, you've probably already read the good stuff and this will be a repeat for you. But, I want to re-purpose it here for you and then link it to the site where I found it. Don't want to take credit for this - this is good work by Ms. Steinberg. What is it - Ms. or Mrs.? I always thought Mrs. meant married and Ms. was not. But if you don't know, what is the proper salutation? In this day and age nothing would be right. Mrs. would be offensive, Ms. is undoubtedly offensive and just shouting out her name like a football coach "Steinberg! nice article now drop and give me 20" is not cool. Carol is too informal. See where we are? NOWHERE'S-VILLE. We can't move in the name of offending someone. Anyway the article is on re-purposing graywater from our showers and laundry for use in the garden. And, she gives us some great ideas for gathering water which we would otherwise waste... Great stuff here. By the way - I am not putting in the entire article it is too long - This is an excerpt.

As many regions’ water costs rise, more people are asking if the water that flows down their drains after bathing and washing—known as graywater—can be used to water gardens. Increasingly, state permitting authorities are saying yes—with conditions.

In Arizona and New Mexico, homeowners can drain graywater right onto their lawns and landscapes. In states where laws are more stringent, especially California, underground graywater irrigation systems—some involving sophisticated water sensors that direct water to where it’s most needed—are popping up. You can help the earth and reduce bills by installing a system yourself. Though regulations vary by location, setting up a fairly simple water-reuse system in your home is becoming easier and more common.

More than soapy water: A graywater overview

Preparing graywater requires a few basic steps: draining it from the house to your graywater system via pipes kept separate from toilet drains; filtering out fibers and greases; then disinfecting the water and treating its carbon. You can take care of the last two parts—disinfecting and treating carbon—by setting up a system in which graywater drains under a few inches of soil, gravel and plant roots. The plants and soil will naturally treat the carbon and disinfect the water.

Though kept separate from what’s flushed down the toilet—called "blackwater"—graywater still can contain bacteria and pathogens that could cause illness, although the small amounts present in most graywater are a low risk, according to a University of Massachusetts study. Graywater also contains carbon from oils, soaps and skin. As in all organic compounds, that carbon will decompose, potentially causing odors and clogging the air spaces in the ground. Health officials advise draining graywater under three to 18 inches of soil, where soil bacteria decompose carbon and destroy pathogens—and where plant roots can drink it up.

State regulations for graywater vary widely, so check with your municipality to be sure your system is legal. Some states consider kitchen-sink and dishwasher drainage blackwater because it contains grease, nutrients and food bits.In most states, graywater cannot be used above ground without a special permit. In nearly all states, a graywater permit requires submitting results of a soils test and an approved plan

If you’re renovating a bathroom or building a house, consider installing graywater drainage pipes—even if you can’t or don’t plan to use graywater now. In the future, water recycling will likely become the norm as this resource gets too precious to throw away!

Three easy ways to treat carbon

Although plants can disinfect gray

water, pouring carbon-laden graywater directly onto your lawn can cause odors and clog drip-irrigation emitters. Avoid this by keeping graywater oxygenated so fast-acting aerobic bacteria can consume carbon and pathogens. Specialists recommend three ways to treat graywater’s carbon: (1) add an air diffuser to your surge tank, (2) design systems that cascade water, or (3) simply apply graywater only to gravel, course sand or well-aerated mulch, all of which have lots of air spaces for aerobic bacteria to work.

A typical graywater system includes:

A surge tank to which all graywater first drains. This tanks equalizes and cools graywater flow so it doesn’t inundate the system with a deluge of hot water. A septic tank or 55-gallon drum, this also serves as a grease trap if the scum is periodically skimmed.

A filter to remove clogging parti

cles such as hair. You can buy a filter (see "Resources," below) or make one with a nylon stocking. For grease and sludge, use a grease trap—essentially a box with a baffle that holds back scum so it can be skimmed out.

Porous substrate, fluffy mulch or aerated tanks to promote fast-acting aerobic biological decomposition.

Irrigation components such as perforated pipe and drip-irrigation lines that get graywater to the plants.

Thirsty plants to use up nutrients and provide root systems that support microbes, which decompose carbon and germs in graywater.

Graywater At Work
Several types of systems use graywater efficiently.

1. Shallow gravel or sand trenches: After filtering graywater in a surge tank, drain it into 18-inch-deep, gravel-filled trenches planted with water-loving species. This California-approved solution is relatively easy to permit in many other states.

2. Sand filter: Drained from a surge tank, graywater can be filtered through a basin full of sand before it’s piped to drip-irrigate an orchard or a greenhous

e vegetable garden. In winter, divert graywater to a below-ground leachfield to avoid freezing.

3. Constructed wetlands: Wet basins full of gravel planted with water-loving species such as elephant ear and papyrus can function as a treatment system before you apply graywater to gardens. Plants and roots should be removed periodically to clear the basin of carbon residue.

4. Drip irrigation: Dispersing graywater to an entire lawn via drip irrigation—usually small hoses or pipes perforated with holes—requires filtering and treatment to avoid clogging.

5. Branched drain system and other mulch-filter systems: Graywater can be dispersed underground via a system of pipes that branch out to holes filled with woodchips, which compost the carbon and particles. In rustic variations of this, perforated basins of woodchips and straw at the outflow pipe are used to filter graywater before it’s discharged to the landscape.

6. Surface drip and spray irrigation: Spraying or otherwise applying graywater above ground usually requires, by law, disinfection through either ultraviolet or ozone disinfection or a reverse-osmosis filter. This must be approved in all states except New Mexico and Arizona.

Super article and great idea.

Upon further research, the Aussie's are killing us in this. They are all over it. I need to look into this a little more

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