Thursday, December 10, 2009

Monticello program conserves water on large scale

Monticello program conserves water on large scale

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For most of us, conserving water means buying an efficient washing machine when the old one conks out, remembering to turn off the tap when we brush our teeth, or watering the lawn only when it’s really necessary. Not Brett Thompson. He manages the City of Monticello’s infrastructure study program, which is aimed at identifying and correcting problems with the city's water and sewer systems.

Here’s the problem Thompson faced with regard to the city water system in Fall 2008. The city water plant was pumping and treating an average of 608,000 gallons of water per day. But the aggregate water used by people on the system was only approximately 517,000 gallons of water a day. That meant that every day roughly 91,000 gallons of water were being pumped from the Mahomet Aquifer, treated, and then lost to leaks somewhere between the treatment plant and the end users—a 15 percent loss. [Photo: A leak in the water line at the corner of State and Center streets sprayed like a geyser when uncovered by Monticello city employees in March.]

Clearly it was time to fix the leaks.

Of course, while fixing leaks in a water system isn’t rocket science, finding them can be tricky, since even fairly big ones are not usually visible above ground. With help from the Illinois Rural Water Association, Thompson and Scott Bailey of the city’s water department began the process of locating leaks by mapping the City’s water and sewer systems, an effort that also benefitted from the assistance of interns in the surveying program at Parkland College.

As the team did the mapping, it also worked to identify which water lines had substantial leaks by measuring the levels of vibration at fire hydrants with a device called a geophone. Higher than usual vibration at a fire hydrant is a sign of a leak somewhere in the line that feeds it.

Other evidence was useful to pinpoint the location of leaks. Thompson and company found several leaks by running a special camera through the city’s sanitary sewer system, which allowed them to see water coming into the sewer line where it was not supposed to. They found other leaks by checking for chlorine in water coming out of storm sewer lines, since the presence of chlorine indicated where treated water was making its way into storm water system. The team even found leaks by checking the output of residential sump pumps that were active during dry weather; in that way they discovered some that were sending water into the ground around people’s homes.

By the end of this past September, the City of Monticello had identified and fixed all 12 of the significant leaks in its water system. As a result, during October 2009, the first full month after all of the leaks were fixed, the water plant pumped an average of 124,000 gallons per day less than it did a year ago, which represents a 20 percent reduction in water use. It’s as though each of the city’s 5,200 residents reduced his or her water usage by almost 24 gallons a day.

Brett Thompson is justifiably proud of the water conservation his team has achieved in Monticello, and he hopes their example encourages other communities to examine their water systems. For more information he can be reached at (217) 762-2583 or bet@cityofmonticello.net.