<a href="mailto: pzekman@cbs.com; mhlebeau@cbs.com; dlblom@cbs.com" target="_blank">Send Your Tips To Pam Zekman</a>By Pam Zekman

CHICAGO (CBS) — Hundreds of thousands of Chicago homeowners are paying for water they don’t use because they don’t have water meters installed in their homes. Their water usage is estimated and as Pam Zekman reports, those estimates appear to be way off.

Unlimited water usage for long showers or watering your garden. That’s the upside for homeowners who still get estimated by the City of Chicago.

The downside? The estimates have nothing to do with the amount of water you use or the number of people living in your home. Instead, under a City ordinance, the charges are assessed based on the frontage or width of your house and the number of sinks, toilets and other water connections the city thinks you have.

“It’s an antiquated formula,” said City Water Commissioner Thomas Powers.

Given that no two houses are exactly the same, the estimates were created “to try and capture how much water could possibly be used at that residence,” Powers said.

When we compared the water bills for two northwest side homes we found out just how far off the estimated bills are. The buildings are roughly the same size, they each have five people living in them, but one has a meter and one doesn’t.

Maureen Conley and Jerry Olson own both 2 flats. They live in the one without a meter and pay the higher bill.

“It makes me angry,” Conley said. “We could be using that money for other things as opposed to paying the City for water that we’re not using.”

Records show the water bills so far this year for the metered account total $346, compared to $670 for the home without a meter.

Olson said that the discrepancy between the two bills showed that the city’s system of estimating water usage is “very inaccurate.”

“There’s probably thousands of people who are being overcharged with this type of computation,” Olson said.

He’s now signed up to get a meter installed in his home.

Since the City began its so called Water Save program in 2009, 32,000 meters have been installed in single family homes and 2 flats. City officials say 94 percent of them have seen their water bills go down.

“We conservatively estimate that people save anywhere from 30 to 40 to even 50 percent on their water bill,” Powers said.

Water meters not only save homeowners money, Powers said, but also makes them more conscious of how much water they’re using, a crucial step towards preserving water in Lake Michigan for future generations.

Christopher Devine has seen those savings since installing a meter in his home last year.

“I think annually we’re paying half or less than half than we used to,” Devine said. “Financially it really paid off.”

As for the 204,000 homeowners still getting estimated bills, the water commissioner says “You are paying more, yeah absolutely, for unlimited water use. Absolutely,” Powers said.

The city guarantees that for seven years a homeowner who installs a meter will not have their bills go higher than they were.

You can sign up for the installation to be done for free by the city, but there’s a 4-5 week wait period. To speed up the process, you can pay a plumber to install the meter and then a city inspector checks out the work.

You can find more information on the program at www.metersave.org and sign up for a water meter on line or call 311 to start the process.

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