Schooners make their way under the Chesapeake Bay Bridge to the starting line for the 26th annual Great Chesapeake Bay Schooner Race on Oct. 15, 2015. (Jonathan Newton/The Washington Post)

The budget proposal released Tuesday by President Trump doubles down on his promise to eliminate Chesapeake Bay cleanup dollars, increasing the pressure on key Virginia and Maryland lawmakers to rescue the funding.

The region has four lawmakers on the powerful House and Senate appropriations committees — Sen. Chris Van Hollen (D-Md.) and Reps. Andy Harris (R-Md.), C.A. Dutch Ruppersberger (D-Md.) and Scott W. Taylor (R-Va.).

Democrats and Republicans in both states have expressed support for cleaning up the bay, but it is ultimately up to them to persuade GOP leaders in Congress to set aside money for the Environmental Protection Agency’s restoration effort.

“It’s like motherhood and baseball,” said Ruppersberger, who represents an area of central Maryland along the bay’s northern edge. “It’s a resource, it’s part of our life. It’s part of what we do and what we stand for.”

[Trump wants to end funding of the Chesapeake Bay cleanup. Here’s who’s fighting back.]

Oyster boats deploy their dredges and work a small section of the Rappahannock River as the sun rises near White Stone, Va., on Oct. 8, 2015. (Steve Helber/AP)

The $73 million program unites six states in the bay watershed — Virginia, Maryland, Delaware, West Virginia, Pennsylvania, New York — and the District of Columbia in a comprehensive program to reduce pollution with the aim of improving water quality.

Environmental scientists say it is working. This month, they gave the bay a “C” for overall health in 2016, the second-highest grade the ecosystem has received in the three decades since officials started keeping score.

Bay restoration advocates say the watershed generates $1 trillion in economic activity through tourism and commercial and recreational fishing and boating.

But the 275-page spending plan released by the White House on Tuesday makes no mention of the environmental or fiscal impacts of zeroing out the funding. Instead, the document devotes half a page to the importance of eliminating federal funding for what it calls “geographic programs,” including cleanup of the Chesapeake Bay and the Great Lakes region.

The goal of the change is to “refocus” the EPA “on core national work,” the document says, adding that federal funding was being used to “perform local ecosystem protection and restoration activities, which are best handled by local and state entities.” (Officials in states fighting budget shortfalls have said they cannot duplicate the money and authority of the federal program.)

Rep. Rob Wittman (R-Va.), who lives on a Chesapeake tributary and is the father of a waterman, said the only way to make sure watershed states work together is through federal oversight.

“I’m alarmed,” he said. “I am adamant that the Chesapeake Bay program is critical to water quality. It is a federal role when you look at the bay being an economic engine, and this revolves around interstate commerce.”

The budget also eliminates the Regional Conservation Partnership Program, a Department of Agriculture initiative that works with farmers to reduce harmful soils from being washed into the estuary, the largest in North America.

Last year, the Chesapeake Bay program funneled about $9.3 million to Virginia, $9 million to Maryland and $2.6 million to the District for state, local and nonprofit projects and staffers. The remainder went to the other state and local governments, nonprofit entities and schools.

Trump’s initial spending plan — the “skinny budget” released in March — confirmed advocates’ fears that the bay program was at risk under EPA Administrator Scott Pruitt. As Oklahoma attorney general in 2014, Pruitt joined an unsuccessful legal challenge to the cleanup program, arguing that only states — not the EPA — had the authority to control pollution levels in the bay.

“Truly, the only word I can come up with is incomprehensible as to why they would zero out a program that has bipartisan support, is clearly science-based and is working,” said Chesapeake Bay Foundation President William C. Baker.

But advocates see a glimmer of hope from a bay budget battle earlier this year in which lawmakers ensured that the cleanup program would continue to be fully funded through the end of September.

Van Hollen said that the short-term win was a result of a partnership between lawmakers in Maryland and Virginia and those in the Great Lakes region, including Sens. Rob Portman (R-Ohio), Sherrod Brown (D-Ohio) and Debbie Stabenow (D-Mich.).

“We are going to fight them tooth and nail,” said Van Hollen, who was a co-chairman of the Chesapeake Bay caucus when he was in the House. “I think we will be successful in reversing this effort.”

Advocates say Republicans are powerful allies in this fight because they are willing to put aside loyalty to a president from their own party when the health of the bay is at stake.

“I don’t see it as a tough spot,” said the GOP’s Taylor, who is from Virginia Beach. “If I agree with the president, then I agree with him. If I don’t, I don’t.”

The GOP’s Harris, whose Maryland district encompasses much of the bay, said the proposal to eliminate funding does not reflect reality.

“There’s nothing we need to do,” he said, when asked about how he will lobby his fellow lawmakers. “The Chesapeake Bay program has broad support in Congress, and Congress appropriates money.”