Try poking around in this for appropriate section.

Here is a link that might be useful: Texas AgriLife Extension Service

A good baseline water quality analysis is something too many growers don't do. They aren't all that expensive and it also monitors how activity around you impacts your supply. That's a nice thing to know. I send my samples to an independent analytical laboratory. I don't remember how I found out about them, but I'd think you could google it pretty easily.

If you use Fafard soil they will do a water test for you. Good Luck Bill

In Alberta our public health clinics have two types of bottles: One for a bacteria check, and one for a basic analysis (about a page of numbers come back.) Both are free.