Summer algal blooms, seafood advisories, and beach closures remind us that water pollution has not gone away, and environmental journalists can still find loads of local and regional stories about it — if they dig. One tool that can help: the state "impaired waters" list.
If you can find the list, you can usually find the most-polluted streams, lakes, and estuaries in a given state. Section 303(d) of the Clean Water Act requires states to maintain lists of waters that do not meet water quality standards. These are public records.
Getting to the lists is a journey. They do not exist in one big, handy national database at the U.S. Environmental Protection Agency (EPA). Instead, under the federalist structure of much U.S. environmental law, they are maintained by state environmental agencies — who do much of the work of implementing the Clean Water Act. So the first step is finding your state agency. EPA has published a helpful look-up directory here.
Once you get to your state agency, you will find a variety of structures and formats, but an often-successful strategy is simply to search on the state agency website for terms like "impaired waters list," "TMDL," and "303(d)." EPA guidelines allow states to fold impaired waters lists in with other required water quality reporting, so you may find what you are looking for in an "integrated water quality monitoring and assessment report" — or something with a similar title.
Another approach is to go through EPA regional offices — which often have web pages linking to state impaired waters lists. A handy link map is here.
The impaired waters program is tied to the requirement for states to develop "total maximum daily loads" (TMDLs) for those waters — a set of aggressive and controversial requirements for cleaning impaired waters up. A national overview of impaired waters basics is here. That page also contains a directory of links to the impaired waters programs in each EPA region.
Pro tip: the water pollution story in your particular region, state, or locality will vary according to the type of waters, the sources of pollution, regional industries, and other factors. Some industries have a stake in tolerating pollution — while other industries have a stake in cleaning it up.