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Grey Water on the Shores of Lake Michigan

In areas of the U.S. where water is scarce and droughts are increasingly frequent, recycling water is becoming a more common practice. But here on the shores of the abundant Lake Michigan, conserving water is often the last thing on people's minds. That's a situation that may be changing. As part of Chicago Matters: Growing Forward, Alison Cuddy explores how one trend, grey water recycling, is making its way into our region.

Ambi: keys and mechanical noise
Mercy Housing Lakefront on the near northside, is an experiment in permanent housing for people who are at risk of homelessness. Since opening last year, the building has also gained attention for its advanced eco-technology, including Chicago's first true grey water system.

MULLEN: Well, here we are this is the mechanical room it's a bit noisy here.

Barry Mullen, a vice president at Mercy, is walking me through the system. It's down in the basement, which is filled with three large holding tanks and a veritable forest of pipes, including some bright yellow ones which carry water draining from the sinks and showers of the 96 residential units upstairs. As the grey water comes into the system it looks pretty dark.

MULLEN: It's hard to really tell through the plastic tanks, but this is black. You know this is a grey water system but this water looks pretty black. In these two tanks where it is ready to go back upstairs it's clear it looks like drinking water. It looks like it is ready to go.

Ready to go flush toilets that is, which is where this water is destined after a space-age looking ultra violet light unit does a final filter to remove any lingering pathogens. When the system is fully operational, Mullen estimates that it helps cut the building's total water demand in half.

Those savings are limited though. Mercy Lakefront is one of only two major grey water systems currently operating in the state. And the concept isn't well understood.  Because of its name, grey water just sounds dirty. And it is, sort of.

Daniel Murphy is the director of Renewable and Sustainable Design for Environmental Systems Design in Chicago.

MURPHY: Grey water has a certain amount of contaminants oil body dirt shampoos that type of thing. But it's not what is considered black water. Black water is anything that comes from toilets, from waste processing facilities, animal rendering that type of thing.

Murphy was involved in the initial design of Mercy Lakefront's grey water system.

MURPHY: It was a tremendous move on the part of the City to let the grey water system at Lakefront go forward. They could have said no my God. What, are you crazy? But they didn't. It got built. That's a big deal, it really is.

It's a big deal because it meant public officials entered largely uncharted territories. Recycled grey water can be approved to flush toilets or for irrigation. But there are no formal grey water regulations in place at the local or state level.

And the use of grey water raises a red flag around water quality standards and public health. Mark Kuechler is the acting plumbing program supervisor for the Illinois Department of Public Health.

KUECHLER: Our primary concern is keeping the grey waste water the grey water separate not connected with any means with the drinking water.

That concern has led the state to move slowly. The Department of Health even temporarily shut down Mercy Lakefront's grey water system until it was satisfied that the grey water piping was clearly marked.

The only other grey water system that has won city and state approval and is in operation is at the Center on Halsted, which serves Chicago's lesbian, gay, bisexual and transgender communities. The Center's system collects rain from the sky and, since it is close to the lake, there's plenty of ground water it can draw upon as well.

Architect Jason Longo led the Center's design team. He realized they could use the water underground.
LONGO: To build a two-level below grade parking garage you need to build essentially a concrete bathtub and sink it into the earth and have a sub-drainage system consistently pumping water out of the basement. And that's perfectly pure water that you could use, no different than if rain were falling from the sky.

Since the Center uses fresh water to flush its toilets, it isn't considered a true grey water system. Still, because the water is used inside the building, where there is a greater chance it could come into contact with the public, it has to be treated the same way Mercy Lakefront treats its wastewater.

LONGO: The purity of the water has to meet certain standards for basically open air water cleanliness. We're meeting the Illinois Bathing and Beach act which is similar to how they test a beach. So if your kids can swim in the water we can flush a toilet with it. The city and state are still moving cautiously in figuring out how to use grey water recycling.

But Longo would agree with water recycling advocates who think grey water is the future.

LONGO: The lake levels are down. They've been down since I moved to Chicago 13 years ago and they've never gone up. And because of the well water issue in a lot of the suburban neighborhoods we're pumping lake water further and further west here.

Daniel Murphy of Environmental Systems thinks individuals too will have to rethink how they're using water.

MURPHY: Betty and Maryanne and their 3.2 kids. Leaving their water run not being cognizant of what they're doing letting the backyard hose run. But again because of where we live and because the price of water is so low people don't think about it.

If water cost 10 a gallon people would think about it. Michael Repkin thinks about it. He's a biologist, but he knows all about plumbing and the energy required to clean water. So he's taking a different approach.

REPKIN: I think my apartment is more of a living laboratory than an apartment.
In his apartment on the north side, there are many experiments in process. And like any good lab rat, Repkin is especially proud of his high tech equipment – the five gallon bucket. A two-bucket system set up in his dining room is currently cleaning his soapy dish water, not with the standard chlorine treatment, but with a slew of minerals and micro-organisms.

REPKIN: All these organisms in here do a fantastic job of actually degrading detergents. There's some in here that also take care of food particles. They're happy now they just got fed. Some people slop the hogs I just slop the bacteria I guess.

In about six to ten days, Repkin's dishwater is ready to be used again. Right now he can get up to five uses of out of the same batch. Mercy Lakefront and the Center recycle their grey water just once. Repkin estimates his total water savings to be in the neighborhood of seventy-five to eighty percent. This amount of effort and scientific know-how seems beyond the scope of the average convenience-happy American.

But Repkin thinks that we need to start trying to get there.

REPKIN: General rule for most humans generally is like thirty days for you to get a new habit and sixty days for it to be so ingrained you would never remember not doing it. Most people are thirty to sixty days away from doing what I'm doing. And it's really just a behavior issue.

So Repkin will keep recycling his water, and limiting his showers to one five gallon bucket a day. And that puts him far ahead of the curve that the state, the city and most residents are still slowly making their way around.

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