OLYMPIA — Gov. Jay Inslee on Wednesday proposed toughening the state’s clean water rules by setting a fish-consumption rate that would be among the highest in the nation.

The question of how much fish Washington residents consume has been a hot issue that has pitted tribes and environmental groups against businesses such as the Boeing Co. and municipalities.

After months of deliberations and pressure from all sides, Inslee said he will set the fish-consumption rate at 175 grams a day — which would protect people who eat about a serving of fish a day. Oregon recently adopted a similar rate, the highest for a U.S. state.

How much fish people eat is part of a complicated formula that determines how clean waters should be. A higher rate theoretically would mean fewer toxic chemicals would be allowed in waters and tougher permitting rules for facilities that discharge pollutants into state waters.

Businesses such as Boeing and others had worried that too-stringent rules would hurt jobs and economic growth because costly technologies would be required to keep certain levels of toxic chemicals out of state waters.

“I’m confident that this rule will not only improve human health, but it’s going to be consistent with economic growth in our state,” Inslee said at a news conference.

Inslee sought to strike a balance, but reactions were mixed Wednesday. Tribal and other groups supported the raised fish-consumption rate but were concerned other factors of Inslee’s proposal could offset those gains.

Boeing is concerned the proposed standard “could result in little to no improvement to water quality and be a substantial detriment to Washington jobs and economic health,” said Tim Keating, senior vice president of government options, in a statement Wednesday.

He and others interviewed said they would review the governor’s proposal and reserve comments until they had more specifics.

A draft rule will be proposed no later than Sept. 30, nearly two years after the agency initiated the process.

The regional head of the U.S. Environmental Agency has warned the state that the EPA intends to take over the process if the state doesn’t finalize a rule by 2014.

Inslee said a clean-water rule would not be finalized until the 105-day legislative session ends in 2015. The governor said he wants legislative input on a package of measures to reduce toxic pollution from chemicals not covered by the federal Clean Water Act or from pollution sources such as stormwater runoff that play a major role in fouling state waters.

The governor said he is asking the EPA to consider the benefits of his full package in protecting human health. A call to the EPA in Seattle was not immediately returned Wednesday.

A coalition of environmental groups is asking a federal judge in Seattle to get EPA officials to step in and force the state to complete a rule or do it themselves.

Janette Brimmer, a lawyer with Earthjustice who represents the Puget Soundkeeper Alliance and others, said this latest delay “bolsters our argument that this is not happening.”

“It’s safe to say that the overall formula that the state is proposing is problematic,” Brimmer said. Her clients are worried a higher fish-consumption rate will be offset by other factors, including variances that would allow companies to release more pollution.

The proposal would also increase by tenfold the allowable cancer risk rate for certain chemicals, another factor that helps determine how much pollution would be allowed in waters. Tribes and environmental groups have argued that would make standards less protective.

“It’s not what we wanted. It’s unacceptable to me,” said Russell Hepfer, vice chairman of the Lower Elwha Klallam Tribe. “It’s good on one side, and it takes it away on the other end.”

Inslee said his proposal would mean more protective rules for a majority of chemicals covered by the federal Clean Water Act, and rules that were just as protective for other chemicals.

Sen. Mark Schoesler, R-Ritzville, said he welcomed the new cancer-risk level but worried that such a high fish consumption rate would hurt consumers who could see rising sewer bills or other increased costs.

Inslee countered he didn’t think there would be significant increases in water bills.

The state has known for years that it needs to update its fish-consumption rate, which federal regulators say doesn’t sufficiently protect those who eat the most fish, particularly Native Americans and Pacific Islanders.

Studies have shown Washington residents eat more fish than other people nationwide, but the state currently assumes people eat about 6 ½ grams a day — or about a small fillet once a month.