We’re in a dry spell, so I water my lawn, but if I had the inclination, I could toss cupfuls of laundry soap on it or just throw my dirty clothes on top of the grass…
So why can’t I divert the water from my washing machine to water my lawn?
Do the health risks associated with graywater warrant prohibiting its use? All I could find in a quick search were warnings to not let the water stand and that fibers could clog a system. If it isn’t a dangerous practice, who are the graywater backers, and how can I help?
This happens quite often in Australia. A lot of sewage treatment plants have their treated effluent pipe to market gardens, parks, golf courses, sporting fields, plantations etc. Many small towns also collect storm water run-off for irrgation purposes.
Don’t woory too much about the laundry water. All the soap in it will bind water molecules to the soil, much the same way as an expensive soil wetting agent.
And the best bit of all is that you are not sending all that phosphorous down the drain, where could possibly contribute to an algal bloom in the wild.
The use of TREATED graywater for irrigation is used widely. There are several communities here in VA that recycle the graywater to irrigate community greenspaces, golf courses, and, in one instance, a turf track for horse racing.
DVous is correct about the phosphorus. That’s why there’s a ban on phosphorus in detergent’s here in VA (excess phosphorus in effluent gives rise to algae blooms, which not only block sunlight and kill SAV (submerged aquatic vegetation), but also deplete DO (dissolved oxygen) when the algae dies and decays).
It totally depends on where you live, Cornflakes. What’s legal (and possible) in the humid, rainy Midwest might be totally illegal (and impossible) in the desert Southwest. There’s tons of stuff on the Web on this. Keep looking.
Just off the top of my head, here in the Midwest, you are generally speaking not allowed to just divert laundry water onto your lawn. The difference between blackwater and graywater has to do with microorganisms, and my local water department (Illinois) considers that laundry water may have poopie germs in it from your underwear, so you can’t use it untreated to water lawns and gardens. I’ve never been interested enough to explore exactly what’s involved in “treating” the water.
Also, from a gardening perspective, laundry detergent may have phosphates in it (as already noted) and may also have high levels of sodium (I think that’s what it was), which can wreck the balance of your soil microorganisms (if you’re an organic gardener). Most advice I’ve seen says run it through a filter of some kind and watch what kind of soap/detergent you use.
Also, the grease in dishwater is not good for rose bushes.
OK, so miniscule traces of fecal matter from underwear is unacceptable, but there’s no problem at all in letting your dog poop on the lawn? Methinks that some legislators could significantly reduce their exposure to coliform bacteria by removing their heads from their present location.
Actually, I think you hit the nail on the head here. Graywater is probably prohibited in cornflake’s jurisdiction precisely because the municipality wants all the phosphorous in the sewage if possible.
Many municipalities remove phosphorous from the waste stream, either with special biological agents or by combining it with other waste streams that remove the stuff chemically (steel-mill water is apparently good for this). Graywater poured on the lawn, on the other hand, will run off into the storm system, which often does not get mixed in with the sewage.
So the result is that graywater irrigation actually increases the total amount of phosphorous reaching the local open water.
How hot is the water and how far away the roses? You could bury the pipe and have a gravel bed under the roses; the gendarmes (or landscape critics, as the case may be) would never know.
I know letting your dog poop anywhere, including your own lawn, without cleaning it up is really frowned on here in California. Is this not the case elsewhere?
>> my local water department (Illinois) considers that laundry water may have poopie germs in it from your underwear
Are you serious? You gotta be joking! Are you required to disinfect your lawn? Do the birds know how to use a toilet? The insects too? Who potty trains them? I know of the proverbial stupidity of politicians and regulators but I find this hard to believe. They can’t be that stupid.
Well…actually, you’re just calm about this because we haven’t had any recent cholera or dysentery outbreaks in the US. Mostly due to improved sanitation and laws against, for example, using contaminated water on the lawn.
Bird, insect, and to a large extent, dog poop are less harmful because there are few zoonoses (shared diseases) between the species (not that I’d advise wading barefoot in the stuff). But what lives happily in one person’s intestinal tract will live quite happily in someone else’s.
Think I have to side with the water dept. on this one.
If faecal matter is such a problem, why is it that manure is recognised world-wide as just about the best fertiliser you can put on your garden? Why is it that zoos market manure as ZooPoo for precisely this purpose?
No municpal authority I know off has banned the use of manure in horticulture. In fact, the largest sewage treatment works in South Australia (which serves a city of about one million people) makes huge piles of people turds, then sells them off to fertiliser manufacturers.
By comparison, the quantity of faeces that escapes with the laundry water is miniscule, and highly unlikely to be an environmental problem.
OK, the fact that shit contains lots of nitrogen and phosphates doesn't mean that it doesn't contain pathogens. Most manure is composted (rotted) which I suspect brings it to the point where the pathogens die. As I said and you failed to read, manure from livestock is not as dangerous as human feces because there aren't all that many cross species diseases, barring parasites. Fertilizer made from human wastes would have to be treated very aggressively to make sure it was safe.
I think you need to do some reading on this. 100 years ago, people died in large numbers every hot summer because of bad sanitation. More men died of disease in the Civil War, largely due to bad sanitation practices, than died in battle. The chance of a diseased individual passing the disease on through grey water is small, but it’s not non-existent.
DVous, the manue that you buy at the local store is NOT the same manure that comes out steaming from the cow’s rear end. Generally, manure has been composted which does a bit to remove the pathogens as well as making it less “hot” (i.e. less nitrogen so you don’t burn the hell out of your garden). Likewise with processed sewage manures like Milorganite. You’re not buying a big bag of human fecal matter, what you’re buying is a bunch of dead micro-organisms. I just read an article on Milorganite and it goes something as follows:
Large tanks of filtered sewage are set out and injected with special organisms. As the organisms feed off the matter in the sewage, oxygen is pumped into the tanks resulting in run-away growth and reproduction of the organisms. Eventually the tank is swarming with organisms and the food begins to run out. The organisms form larger clusters as they become stressed from the lack of living space and lack of food. At a certain point, the oxygen is turned off and the organisms die, forming a layer on the bottom of tank. Said layer is scraped off and dried, then bagged. So you’re really buying a dried bunch of human fecal matter eating organisms, not a big bag of human dung.
Finagle, I still cannot believe laundry water would be dangerous in the least if you use it to water your yard. Sorry, i just do not believe it until you give me a couple of people who died or at least got sick from this. I do not think you will find a single case.
Problem is, if someone got sick or died, it’s not like you’d be able to trace it to a particular source. Still, there are treatment options for greywater which totally eliminate the risk (www.greywater.com)