Recycled Water; Fit for human consumption?

July 26, 2006 11:14 PM

There's a bit of a debate going on in my home state of Queensland about using recycled water for drinking purposes. Premier Peter Beattie says that London has been doing it for years and it's never hurt anyone but Opposition leader Lawrence Springborg says that's a lie. This raises a few questions for me, and I want some answers.

What I basically need to know is...

1. Does London use recycled water for drinking purposes, and if so, what does it taste like?

2. Just how safe is recycled water to drink?

I'd like an informed opinion on this so I can either set my mind at ease when (if) it happens, or start budgeting to have fresh water delivered to my home. Thanks in advance!

posted by Effigy2000 to grab bag (22 comments total)

There's no generic answer to your second question. It's entirely a question of the actual purification process used.

Unless the engineers are incompetent, I would suspect there's nothing at all wrong with it.

This kind of thing isn't as bit a deal as you think it is. Every city in the Mississippi river basin takes their water out of rivers which are part of it, and puts their reprocessed sewage back into those same rivers. The ones downstream process water for drinking purposes which includes effluent from sewage treatment plants upstream.

The water in New Orleans tasted pretty foul when I was there 30 years ago, but I don't think it's because of upstream sewage. I've had water which is just as bad in other places where that wasn't the case.

What you're having is known to people in the trade as the "Yuck" factor. San Diego wanted to reprocess its sewage for drinking, but there was local opposition. It turned out that the water coming out of the pilot plant was indistinguishable from the stuff everyone was already drinking. But just the thought of where it had come from...
posted by Steven C. Den Beste at 11:22 PM on July 26, 2006

For a nice presentation of how water get to your home see if you can get ahold of the Good Eats episode Water Works Part 1. Of course, he uses an example here in the states but I would hope that they have similar standards and processes in place across the pond. The short of it is, todays drinking water treatment plants produce an amazing amount of great drinking water. While not perfect (health incidents have been recorded, though this is RARE), most areas of the United States have better tap water than ever before in recorded history. I'd say you're safe. If you're really paranoid or your tap water just doesn't taste to your liking, buy an under the sink filter or get a britta pitcher. Doing your own filtration is probably going to be alot cheaper than having water delivered to your home, if not also cheaper than buying the bottled stuff yourself.
posted by crypticgeek at 11:31 PM on July 26, 2006

Singapore does this, as does Israel. It's very common around the world.
posted by delmoi at 12:02 AM on July 27, 2006

It's harmless. You can think of it like dialysis on an industrial scale. Many, many places in the world dump unprocessed or part-processed sewage in one part of a river, then miles downstream another town pumps it out for its drinking water. It is my understanding that this actually happens, on the sly, in Sydney. And damn, you should see the porridge I used to have to drink in Adeladie! On top of that, never mind the fact that in a typical Australian catchment, the water is already full of unprocessed cow, sheep, kangaroo, dog, fox, koala, possum, pig, cat and fish shit. Treating the sewage to drinking water quality first is a major step forward, and is better than what a lot of people have to put up with.

The objections in the case of Toowoomba come purely from people who don't understand the SCIENCE. People who feel, on some kind of philosophical level, that water that once contained human waste always contains human waste, even if there's not an atom of that waste physically left in it. This is a bizarre and ignorant argument, since all the water we have on earth has been here forever, and has been through the guts of millions of organisms already. Unfortunately, it's hard to get through to these people, and the Australian environment is going to suffer for it.
posted by Jimbob at 12:10 AM on July 27, 2006

Wikipedia (insert disclaimer here) has a pretty decent article about reclaimed water, which is also a pretty good Google Search Term
posted by stovenator at 12:13 AM on July 27, 2006

My executive summary: Fearing recycled water is akin to believing in homeopathic cancer treatments, on my batshitinsane scale.
posted by Jimbob at 12:16 AM on July 27, 2006

For a totally subjective opinion, London water tastes better than Brisbane water.
posted by goo at 12:35 AM on July 27, 2006

Many, many places in the world dump unprocessed or part-processed sewage in one part of a river, then miles downstream another town pumps it out for its drinking water. It is my understanding that this actually happens, on the sly, in Sydney.

I doubt that, since Sydney's "rivers" are mostly drowned river valleys full of salty seawater. They freshen up the further upstream you go, but are pretty teensy little trickles by that stage - the watershed from the Blue Mountains to the coast is just not large enough or rainy enough to sustain large freshwater rivers, and desalination has definitely not been introduced yet.

AFAIK, our effluent goes into the ocean after some treatment, notably around Bondi & Manly beaches, hence the slang term, "Bondi cigar"...
posted by UbuRoivas at 12:42 AM on July 27, 2006

Apart from that, our water comes from dams, not rivers. And you can't even enter the catchment areas, let alone pump effluent into them. *grumbles*
posted by UbuRoivas at 12:49 AM on July 27, 2006

I think it's not at all a good idea. All recycling purification schemes under discussion of which I'm aware depend for their safety on a power grid which never goes down for an extended period. Not that many places in the world, if any, can guarantee such a rosily-lit future.
posted by jamjam at 1:07 AM on July 27, 2006

UbuRoivas, I saw it on a documentary on the ABC, don't know much more than that. Some creek in the Blue Mountains where there was a sewage outlet, and further down the catchment that creek drained into a dam. But I've got no names or references, so take it as you will.

All recycling purification schemes under discussion of which I'm aware depend for their safety on a power grid which never goes down for an extended period.

Surely a power failure could immediately cause the treatment plant outflow to close? Seems pretty trivial to me.
posted by Jimbob at 1:40 AM on July 27, 2006

I lie, it wasn't on the ABC, it was on The Weather Channel's Running On Empty series.
posted by Jimbob at 1:42 AM on July 27, 2006

Every city in the Mississippi river basin takes their water out of rivers which are part of it, and puts their reprocessed sewage back into those same rivers.

This isn't true. Some cities in the Mississippi River Basin do not take their water from rivers. Memphis, for example, does not take its water from the Mississippi River, but from a series of aquifers that lay underneath the city and the the surrounding area.
posted by jayder at 2:06 AM on July 27, 2006

Um... what? Define 'recycled water'. Where do you think the 'new' water comes from? Have you never heard of the water cycle? Do you think sewage goes to some kind of used water landfill?
posted by reklaw at 3:07 AM on July 27, 2006

jimbob: yeh, maybe the outflow from Lithgow makes it into the catchment, now that you remind me. Not that it makes us sick. Apart from the giardia contamination a coupla years back, I guess...
posted by UbuRoivas at 5:13 AM on July 27, 2006

Canadians will all be familiar with a small town called "Walkerton" where E.Coli infecteed the town's water supply, killing several people and leaving many more with permanent kidney damage.

They got their water from ground wells.

Rainwater washed over fields fertilized with cow manure and drained into the wells, infecting the water supply. Then it was a string of cockups, but the point is that without treatment, no water source is 100% safe.
posted by GuyZero at 6:35 AM on July 27, 2006

I wish SE Qld would just get over its damn self and recycle the water already. Recycled sewage will probably be better than the yellow water I currently get out of my tap at Chermside.

Yes we have a Brita filter.

(sorry for adding noise to your thread)
posted by chronic sublime at 6:58 AM on July 27, 2006

jimjam, all modern minicipal water systems depend on power being available, regardless of the water source. Pumps, input purification all requires power. Without electricity, everything stops at a municipal water plant.

I am completely bemused by the oq as a Canadian. Montreal, indeed most of Quebec, for example, gets its water downstream of the Great Lakes, which has somewhere between 20 to 30 million people living around them, all dumping effluent into the lakes. Montrealers are not more sick than the rest of the country, indeed Montreal has one of the best water systems in Canada.

Riviers on the praries travel thousands of kilometers from the continental divide to Hudson's Bay, with each city and small town taking water from the river and returning it's watewater. Yet people in Churchill aren't dying of dissentary.

Recycling water is a fifty-year old technology that's well understood. If the system in maintained well (for counter example, see Wlakerton, ON above), tap water is safer than bottled water.
posted by bonehead at 7:22 AM on July 27, 2006 [1 favorite]

Thames Water takes water from the Thames (unsurprisingly), filters it at plants like Coppermills and sends it along to consumers where, leaks and pollution notwithstanding, it's actually pretty good. Waste water, including sewage, is treated in plants like the one at Crossness (pdf), from where 'the treated effluent flows over the weirs as clean water where it is strictly monitored before being discharged to the River Thames'. And the cycle begins again.
posted by jonathanbell at 7:58 AM on July 27, 2006

Every city in the Mississippi river basin takes their water out of rivers which are part of it, and puts their reprocessed sewage back into those same rivers. The ones downstream process water for drinking purposes which includes effluent from sewage treatment plants upstream.

Yeah:

The breakfast garbage that you throw in to the Bay...

They drink at lunch in San Jose.

For what it's worth, Pinellas County Florida supplies recycled water for irrigation (and they can't make enough of it :-), in purple pipes, and the (purple) signs they put up everywhere it's used for municipal irrigation say "No Beber", quite prominently.
posted by baylink at 8:10 AM on July 27, 2006

start budgeting to have fresh water delivered to my home

Keep in mind that many "purified" bottled water businesses start with water from the municipal supply.
posted by Good Brain at 9:04 AM on July 27, 2006

Davis California also provides recycled sewage water for irrigation purposes, and it too isn't safe to drink. But the process of creating it is entirely different than for a normal water works. They deliberately leave sewage in the water, both because it makes it better as irrigation water, and so that they don't have to get rid of the stuff.

That has nothing to do with the kind of water recycling plant that we're talking about. Entirely different process, entirely different results.
posted by Steven C. Den Beste at 3:32 PM on July 27, 2006