Nutrient Polluters Cut Back To Help Clark Fork

An experimental 10-year program to clear life-choking nutrients out of the Clark Fork River will begin April 17 after three years of planning.

Three of the four largest contributors of the nutrient pollution voluntarily will begin reducing their output. But the biggest - the city of Missoula - will not participate for several years because of the cost.

The cutbacks will come at Stone Container Co.’s paper mill in Missoula and at municipal sewage treatment plants in Butte and Deer Lodge.

The four polluters account for about 80 percent of the nutrients that are choking the river - phosphates from detergents and nitrates from human waste. They cause excessive algae growth, which robs the river of oxygen.

The Clark Fork River flows into Lake Pend Oreille in North Idaho, which, in turn, is the source of the Pend Oreille River that flows through northeastern Washington.

Arsenic, copper, cadmium and zinc, all toxic to aquatic life, flowed unchecked into the Clark Fork’s headwaters at Butte during the town’s mining boom at the turn of the century. That pollution was the target of the federal Superfund program.

“Butte is the headwaters of the river, and Montana is responsible for what happens in Idaho and Washington,” said Bob Farren, Montana’s representative on the Tri-State Implementation Council board of directors. “We also don’t want to get blamed by the other states for the river’s problems.”

The council brings together state and federal agencies, business, industry and environmental groups from Montana, Washington and Idaho.