By Bob Uphues
With 51 percent of its water mains more than 100 years old, the village of Brookfield is reevaluating how it approaches replacing those old pipes, moving more quickly to replace them instead of waiting until they start experiencing a series of breaks.
While the new policy hasn't officially been put into place, Village Engineer Derek Treichel convinced the village board to vote unanimously on Nov. 11 to fund the replacement of nearly 2,000 feet of century-old water main under Park Avenue between 31st Street and Monroe Avenue next year when that street is due to be widened and repaved.
In addition to a modest history of breaks – four in the past decade, according to Treichel – the Park Avenue water main also doesn't supply an adequate fire flow through its 6-inch pipe, which has corroded, restricting flow even further over the years.
"As the pipes get older the effective internal diameter shrinks down quite a bit, and the natural flow you get through those mains is much less than when they are new," Treichel said.
The remaining water mains below streets up for resurfacing next year don't exhibit such fire flow problems, said Treichel. He did say that about 25 percent of the village's water mains aren't able to provide fire flows recommended by the Insurance Services Office, which rates municipal fire protection capabilities and can affect fire insurance premiums.
The new Park Avenue water main, which will be located beneath one of the sidewalks, will be an 8-inch main, which will double the flow, said Treichel. In addition to the main, new copper service lines will connect the main to B-boxes on each property.
As part of the restoration, a new sidewalk would be poured over the new main, allowing any future repairs to be done without tearing up the street. The old main will be abandoned in place under the street.
Including both engineering and construction, the water main replacement is estimated to cost about $660,000. It will be bid as part of the 2020 street improvement package early next year. Costs related to the water main replacement will be paid out of the village's water and sewer fund, whose revenues come from water system user fees.
Treichel said he has been meeting periodically with public works staff to develop a more proactive water main replacement plan. With the life expectancy of water mains estimated between 75 and 100 years old, more than half of the village's water mains are reaching the end of their useful lives.
Instead of being faced with a massive replacement project as older mains begin to fail, Treichel said the plan is to tackle the older main replacement in a more systematic fashion to spread out that expense.