I am skeptical of reports published by the cities. There is incentive for the reports to skew positive, since otherwise individuals can lose elections/jobs/contracts.

So I looked back at the 2014-2016 reports from Flint, Michigan to see if they correctly predicted the water crisis.

They did, but only very subtly.

In 2014, there was a single violation of too many total trihalomethanes: https://www.cityofflint.com/wp-content/uploads/2014/01/CCR-2...

In 2016, there were no declared violations, even though the 90th percentile sample of lead concentration (20 ppb) was over the 15 ppb limit: https://www.cityofflint.com/wp-content/uploads/City-of-Flint...

Also note that while in the US the lead concentration limit is 15 ppb, Canada has recently reduced its limit from 10 ppb to 5 ppb. Nearly every US city I've looked at exceeds 5 ppb.