This month, Big Ag lobbyists including Iowa’s Farm Bureau and Pork Producers Association took the side of the Environmental Protection Agency in the landmark lawsuit by Food & Water Watch seeking to clean up factory farm water pollution nationwide. In backing the agency ostensibly responsible for environmental protection, they join the ranks of some of the nation’s largest corporate lobbying groups, including the National Pork Producers Council, American Farm Bureau Federation, US Poultry & Egg Association and the United Egg Producers, which have consistently worked to gut wetlands protections and stonewall climate action.

Abdication of government responsibility can make for strange bedfellows. The Farm Bureau once called for the EPA to be abolished. Now it’s singing a different tune. But where polluting corporations see a job well done, we see a job not done at all.

No industry has been more successful than Big Ag at evading environmental regulation. And nowhere is that on better display than in Iowa. The fact that Big Ag is weighing in on the side of the EPA in this case speaks volumes about the failures of our environmental regulators.

Agriculture is both the leading contributor to pollution in America’s waterways and the least regulated. Today, fewer than one-third of the country’s 21,000-plus largest factory farms, also called concentrated animal feeding operations or CAFOs, have Clean Water Act pollution permits. In Iowa, more than 4,000 CAFOs operate without any water pollution permits at all. The result is a rogue industry that pollutes with impunity.

At any given moment in the U.S., there are 1.7 billion animals living in strict confinement on factory farms – a 47% increase in just two decades. Iowa is home to more of these factory farms — and their waste — than any other state. Operating as sewerless cities of densely packed livestock, Iowa’s industrial livestock operations produce 109 billion pounds of pathogen, nitrate and pharmaceutical-laden waste linked to everything from cancers and birth defects to mass fish kills and aquatic dead zones, each year — 25 times as much as the sewage produced by the state’s entire human population.

This animal waste contaminates drinking water with dangerous E. coli and nitrates, chokes waterways, kills aquatic life, and renders water recreation unsafe. E. coli is the leading cause of Iowa’s impaired waterways, which include more than half of all assessed lakes, reservoirs, and river and stream segments. Meanwhile, scientists increasingly link nitrates to Iowa’s worsening, second-in-the-nation cancer ranking.

We are demanding better. We at Food & Water Watch sued EPA last summer over decades of failure to regulate factory farm water pollution. Standing with us are 12 co-petitioners, scores of academics, family-scale farmers, and some of the nation’s most prominent environmental justice organizations, including the NAACP and Southern Environmental Law Center.

Our case seeks to force federal regulators to protect our waters and our health by finally bringing the largest, most polluting CAFOs under the umbrella of the Clean Water Act — just as the law requires. To do this, EPA must ensure all polluting CAFOs have permits, and strengthen the permits so they are actually effective in safeguarding clean water.

Hundreds of millions of corporate lobbying dollars have produced a consistent failure to regulate agricultural water pollution, penalizing farmers who raise animals sustainably, and rewarding those who pollute their way to profit. And time and time again, as front-line communities, farmers and advocates pursue improvements to the dirty status quo, corporate front groups stymie progress.

This time must be different. Our lawsuit calls on the judicial system to act where regulators have failed, and finally compel the EPA to get back to work for the public and the environment, not industry lobbyists. Decades of inaction, coupled with intense pressure from Big Ag, make clear that EPA will not act on its own.

Wenonah Hauter is the founder and executive director of the national environmental advocacy organization Food & Water Watch, and the author of “Foodopoly: The Battle Over the Future of Food and Farming in America.”

This article originally appeared on Des Moines Register: Animal agriculture pollutes with impunity; we’ve sued to change that.