The issue is finding published articles about it. Having family members and friends who live in some of these towns is how I know about it. A friend was a ferry pilot in a Michigan town for about a year and described his normal day through town, and how it was impossible to date anyone, because every time he tried to date someone he found they were addicted to meth. I have family that lives in Alabama, and they haven't met anyone in their town that isn't addicted to meth.

That was years ago. Seems heroin is more of a problem.

The articles I linked mention ~34% of the testing in a state showing positivity for meth, so I'm not sure why you'd be surprised that entire towns in that state may be addicted.