The Obama administration added to its steady churn of utility regulations Wednesday, finalizing new cross-state air pollution rules aimed at protecting the East Coast from harmful power plant emissions in the west.

The Environmental Protection Agency finalized the updated rules after a long series a court actions, stays, changes and reversals that go back to President Obama's first term in office.

The Cross-State Air Pollution Rule is aimed at protecting communities on the East Coast from smog-forming pollution as it crosses state lines. The agency said the rules, which primarily affect coal power plants, will help states meet EPA's separate 2008 national standards for controlling ozone emissions that cause smog.

Wednesday's update to the cross-state rule is targeted at reducing nitrogen oxide emissions from power plants, which are problematic during the summer and "contribute to downwind ozone problems in the eastern U.S.," EPA said.

Janet McCabe, the EPA's acting air pollution chief, called the regulations a series of "common-sense actions that power plants can take to quickly and affordably reduce this harmful pollution [that] will help protect the health and lives of millions of Americans, restore visibility at our nation's most treasured parks, and ensure that air quality continues to improve in the eastern United States."

The new power plant rules are aimed at curbing nitrogen oxide emissions in 22 states. The emissions can cause breathing problems in healthy adults and are particularly harmful to asthma sufferers, children and the elderly.

The EPA, alluding to the nation's ongoing switch from coal to natural gas for electricity production, said it estimates that beginning in 2017 the rule "and other changes already underway in the power sector" will cut emissions by 80,000 tons, which is a 20 percent reduction from 2015.

Natural gas from fracking has become the nation's leading source of low-cost fuel for producing electricity at power plants. Natural gas power plants produce far less pollutants such as nitrogen dioxide than coal plants, while producing about half of the greenhouse gas emissions.

EPA officials in previous statements have referred to the increased use of natural gas, the lower cost of renewables and more efficient technologies as "changes" already making the grid cleaner.

The benefits of the rule will far outweigh the costs, the EPA says, according to its cost estimate that accompanied the final regulation.

The final rule will cost an estimated $68 million to implement, while providing annual benefits of up to $880 million beginning next year.

"For every dollar invested, American families would see up to $13 in health benefits," the EPA said.

The cross-state rule is also expected to make the air at the nation's parks cleaner and clearer, the agency said.