An aside: lead exposure is thought to lead to increase violence. I wonder if Chicago having the most lead pipes is also a contributing cause of their (reputed) crime problem.
Broadly speaking, maintaining this infrastructure is expensive because the need for labor is unavoidable and it is labor intensive.
These Chicago pipes are end of life and need replaced. They have been working on it for at least 20 years.
*in theory they claim to be working hard to better coordinate this between agencies.
This is true. For the private sector, it works pretty well. Road digging permits are posted on their webpage 6+ months in advance. If you see one on a section of street you planned to do work on, you are allowed to piggyback on the project and share the cost. If you don’t, you pay the entire cost. So there is huge incentive to coordinate. But city agencies? Not quite so incentivized.
Some states are more schizophrenic than others. New York is simultaneously mandating replacement with high pressure gas mains that require biannual inspection and banning gas lines.
Lead pipes are an engineering and chemistry issue. Pipes that are functioning properly don’t need replacement.