WHILE PORTLAND OFFICIALS spar over costly federal rules for the city's drinking water, another widespread and potentially expensive water issue has silently crossed the finish line.

As of last week, the US Environmental Protection Agency (EPA) allowed Oregon to set some of the nation's strictest water quality rules for rivers. And while the new rules are a victory for Native American tribes that depend on healthy fish supplies, financial and technological challenges loom for city treatment plants, agricultural facilities, and other industries.

Runoff from pollutants ranging from arsenic to mercury will now face increased restrictions based on new statistics that show tribe members eat far more river-caught fish than previously thought. The new standards could take as long as five years to fully take effect.

Kim Cox of Portland's Bureau of Environmental Services says she is unsure how long it will take to get the city up to speed or how much money compliance will cost.

"We know we'll have to make some significant technological changes, I just hope it's a minimal effect," Cox says. "Anything that needs to meet water-quality standards could be affected."

In 2008, the Confederated Tribes of the Umatilla Indian Reservation (CTUIR) and the Columbia River Inter-Tribal Fish Commission (CRITFC) urged the EPA to adjust river regulation standards. The old standards assumed tribe members ate only 17.5 grams of fish a day—157 grams short of the tribes' own 2008 estimate. After a slew of public hearings with farmers peeved about the cost of controlling runoff, the EPA finally welcomed the tribes' request. On October 17, Seattle's EPA office announced its new criteria: 104 pollutants will meet increased restrictions on the assumption that people eat 175 grams of fish a day. (Officials deny it was a longstanding decimal-point error.)

"This really demonstrates Oregon's dedication to clean water," says Diane Barton, water quality coordinator for CRITFC. "It's also an economic benefit, making fish healthier for the consumer. While it may take some time, it's worth our hard work."

Despite the increased regulations of agricultural and forest product runoffs, the EPA says the state, not the feds, should continue to oversee the rivers. Kevin Weeks of the Oregon Department of Forestry says he doesn't think this boost will even affect his field. "Forest management companies are very much endangered in the rule-making process," he says. "And both private- and state-owned lands have tight water-quality rules already."

But EPA spokeswoman Christine Psyk acknowledges the potential consequences from the restrictions. "It's challenging. It's going to take time and monitoring for industries to get up to speed," she says. "But it's more than that: This is a huge step in Oregon's commitment to human health."