According to 23 WIFR News on May 12, 2005:

Some of the city’s oldest pipes are causing a new problem for workers as more are bursting across the Stateline. Rockford’s water main system gets replaced at a rate of just under one mile per year, but Water Superintendent Tim Holdeman says that’s not fast enough.

“The city of Rockford and the water utility is at a turning point,” Holdeman said. “We have about 120 miles of our water’s distribution system that’s over 80 years old. Replacing one mile a year and trying to get 120 miles replaced is going to take us longer than what we have.”

There’s 850 miles of water main pipes throughout the city with one mile out of every five being more than 70 years old, and some even dating back to the 1890’s.