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Concentrated animal feeding operations, or CAFOs, produce hundreds of millions of tons of manure in the United States annually. These industrial facilities often dispose of this waste by spraying it on their fields as fertilizer. Rainfall then washes the waste into rivers and streams, carrying with it pathogens hazardous to human health, such as E. coli and salmonella.

Surely the Environmental Protection Agency regulates these practices to protect our waterways? Actually, the EPA doesn't know the most rudimentary facts about many of these factory farms: how many animals they process, the amount of waste they produce, even where they are located. Although the agency has the authority to regulate CAFOs under the Clean Water Act, these operations have mostly regulated themselves.

NRDC and its partners, the Sierra Club and the Waterkeeper Alliance, sued the EPA to improve its oversight of CAFOs, including how they dispose of manure. In a May 25 settlement, the agency agreed to propose a plan within a year to collect important information from the thousands of industrial farms across the United States.

If its survey is thorough, the EPA will finally have the information it needs to clean up our waterways, says NRDC senior attorney Jon Devine, who, along with colleagues Michael Wall and Jonathan Wiener, helped lead the push for change.