WEST SILOAM SPRINGS, Okla. (AP) _ The Illinois River is drab green when it rushes into Oklahoma just south of here, but it's not Arkansas mud that dirties the scenic waterway.
Oklahoma policy-makers blame phosphorous from sewage, animal waste and fertilizer in northwest Arkansas for the green tint, which typically worsens as the weather warms and the river's flow slows.
The color, odor and potential danger to aquatic life has led Oklahoma to propose tighter water quality standards for the Illinois and the state's five other scenic rivers.
The standards have triggered back-and-forth threats from the neighboring governors _ like-minded Republicans who are otherwise friends _ in the second major fight between the states over the Illinois.
The Oklahoma Water Resources Board has approved a limit of 0.037 parts per million of phosphorous in the rivers, to be achieved in 10 years. The standards will take effect unless the Oklahoma Legislature or Gov. Frank Keating strikes them down.
Oklahoma says the standards are necessary because a past voluntary effort failed to adequately reduce phosphorous in the Illinois, which is well above the proposed limit. Arkansas Gov. Mike Huckabee says the proposed standards are impossible to achieve and will harm development in growing northwest Arkansas.
Talks between environmental officials from both states continue, but the conflict wasn't that peaceful at the outset.
In late March, Huckabee told Oklahoma to back off on the phosphorous standards or he'd place tougher limits on chloride in the Arkansas River, which flows east from Kansas, through Oklahoma and into Arkansas.
Huckabee, who repeated the threat again about two weeks later, said chloride from Oklahoma's petrochemical industry was polluting the river.
Keating responded by calling for negotiations but threatened to sue Arkansas if it refused to follow his state's standards. Arkansas has since backed down, saying it has no plans to change its chloride standards.
Keating and Huckabee, who have gone duck hunting and always eat dinner together at governors' association meetings, tempered their tough talk through it all by stressing their friendship.
``They're both doing what they think is in the best interest of their states,'' said Keating spokesman Dan Mahoney. ``Keating has no ill feeling toward Gov. Huckabee at all. He'd be doing the same thing if he were in his position.''
The two states first fought over pollution in the Illinois in 1982 when the city of Fayetteville, Ark., wanted to build a new waste water treatment plant on the river.
Arkansas won the culminating 1992 U.S. Supreme Court decision, but revisionist history might suggest that Arkansas ultimately lost.
While the justices allowed Fayetteville to build the treatment plant, the court also ruled that upstream states are subject to downriver state's water quality regulations.
Absent that, Arkansas now could just turn up its nose at downstream Oklahoma.
Ed Fite, administrator of Oklahoma Scenic Rivers, said the Illinois is still fairly healthy. But it's changing from a river rich in animals to one that's filling with plants, he said.
Phosphorous encourages algae growth, which turns the water green, creates a foul smell and taste and threatens fish by reducing the river's oxygen level, he said.
The damage is difficult to quantify in a state with just six scenic rivers, all in the Oklahoma's eastern half where the natural beauty attracted many of the residents.
``The Illinois River generates about $12 million to Cherokee County by itself, and the aesthetic value is not computed,'' Fite said.
Fite said scientists have determined that populous northwest Arkansas, also home to hundreds of high-volume poultry farms, contributes more than four times the phosphorous in the river than Oklahoma does.
``It comes from anybody that lives in the basin,'' Fite said. ``Some folks want to point specifically at the poultry farmers, and animal waste does'' contribute, but there are other sources.
The chicken and turkey farmers in northwest Arkansas agree. They point to the golf courses sprouting up all over northwest Arkansas that lay commercial fertilizer on fairways and greens.
The farmers, none of whom wanted to be identified, say phosphorous runoff from chicken waste is the unavoidable result of efficient farming, something that consumers demand.
``Sometime, this country's going to have to decide between cheap food and environmental issues,'' said one farmer from tiny Nicodemus, Ark., who raises chickens for Tyson. ``They're not going to have one without the other.''