Topeka ? Runoff from Kansas and many other states flows into the Mississippi River and then the Gulf of Mexico creating a dead zone that harms aquatic life.

Environmentalists are suing for federal restrictions to control the nutrient runoff from ranches, farms and sewage systems, but Kansas Attorney General Derek Schmidt says those regulations would hurt agriculture.

On Monday, Schmidt announced he is seeking to intervene in the litigation filed in federal court in New Orleans.

“The decisions that will be made in that Louisiana courtroom have stark implications for production agriculture in Kansas,” Schmidt said. “Kansas has a keen interest in the outcome of this case, so we’re asking to be at the table to defend Kansas interests when the issues are presented and decided,” he said.

Environmental groups, including the Gulf Restoration Network and Sierra Club, want the Environmental Protection Agency to impose new regulations on nitrogen and phosphorous pollution, much of which comes from fertilizers. The nutrients stimulate algae growth, depleting oxygen levels in the water.

The dead zone, or low oxygen area, that forms in the Gulf of Mexico along the coast of Louisiana and Texas has ranged from 5,000 to 8,000 square miles and has an adverse effect on the $2.8 billion commercial and recreational fishing industry, according to the lawsuit.

The lawsuit seeks to force the EPA to set numeric standards for nitrogen and phosphorous pollution. Currently, nutrient standards have been left to the states. Kansas and many use what is called a narrative criteria where bodies of water are classified as to what they should be able to maintain and what they shouldn’t have.

Schmidt said that system works.

“State governments and agricultural producers in the Mississippi River Basin have worked successfully for years to minimize nutrient runoff and will continue to do so,” Schmidt said. “Discarding state efforts in favor of a one-size-fits-all federal standard imposed by the EPA is unnecessary and would hurt Kansas agriculture and our state’s economy,” he said.

In addition to Kansas, the states seeking to join in the Louisiana litigation are Alabama, Arkansas, Iowa, Kentucky, Missouri, Nebraska, North Dakota, Oklahoma and South Dakota. A number of agriculture groups also have intervened in the lawsuit.

Laura Calwell, Kansas riverkeeper for Friends of the Kaw, said, “Nutrients are becoming a bigger and bigger problem,” and she noted that Milford Reservoir was closed to recreation during the Labor Day weekend last year because of an algae bloom.

In 2010, Friends of the Kaw — Kaw is the nickname of the 173-mile Kansas River — notified the EPA that it intended to sue for tougher water quality standards. But then the organization decided not to purse litigation because of the political climate, Calwell said, citing the recession and the 2010 elections, which produced a more conservative Congress and state Legislature.

Calwell disagreed with Schmidt’s statement that the states can handle the issue and supports the lawsuit filed in Louisiana.