Panelists and lawmakers agreed at a congressional hearing Tuesday that the Bay is getting better, albeit slowly, but they also called for a strong federal role in cleanup efforts — especially when it comes to paying for it.

The field hearing of the Senate Environmental and Public Works Subcommittee on Water and Wildlife was convened by subcommittee Chair Sen. Ben Cardin to assess progress under the 30-year-old state-federal Bay Program partnership.

“What we do here is not just important for the Chesapeake Bay, it gives us a model for other watersheds around the nation,” Cardin said at the hearing, which took place at the Chesapeake Bay Environmental Center in Grasonville, MD.

Nicholas DiPasquale, director of the EPA Chesapeake Bay Program Office, said efforts over the years had successfully reduced pollution from wastewater treatment plants, farms, urban stormwater and air pollution. As a result, he said, nitrogen and phosphorus concentrations have decreased at 70 percent of the river monitoring sites in the Bay watershed since 1985 and Chesapeake water quality is showing signs of improvement.

Nitrogen and phosphorus spur algae blooms, which degrade water quality. When algae die, they are decomposed in a process that depletes the water of oxygen, causing so-called “dead zones.”

A cleanup plan imposed by the EPA in December 2010, called the Chesapeake Bay Total Maximum Daily Load, set enforceable limits on the amount of nitrogen and phosphorus that can enter the Chesapeake from each state and major river. States were required to write detailed cleanup plans showing how they would achieve all needed cleanup actions by 2025, and to establish interim goals every two years.

“Those actions will help ensure that we maintain our progress,” said DiPasquale, adding that all of the states in the watershed “are largely on track” to meet their current two-year goals.

Nonetheless, Cardin said, the Bay has many problems, from the acreage of underwater grasses — a crucial habitat for many species — declining sharply in recent years, to populations of important fish species such as shad and menhaden hovering at low levels.

“There is no question that we need to redouble our efforts,” DiPasquale said.

Cardin called for the EPA to work harder to promote nutrient trading in the watershed. Trading — which has been controversial, especially among many environmental groups — allows those who discharge more than their allocation of a pollutant to purchase credits from someone who controls more than is required of them. In theory, the overall pollution goal would still be met met.

“The administration could move more aggressively on nutrient trading programs,” said Cardin, who called it a “win-win” proposition that could help local governments reduce cleanup costs by paying farmers to implement more runoff controls.

DiPasquale said the EPA is not developing its own trading program, but is instead providing guidance to states to help them develop programs that are consistent with meeting overall Bay objectives. “Once the rules of the game are well defined, we will see more participation” in trading programs, he said.

Cardin also asked when the EPA would release the long-overdue stormwater rules required in 2009 as part of the settlement terms of a lawsuit brought by the Chesapeake Bay Foundation. The EPA was supposed to propose the rules by September 2011 but has yet to do so.

DiPasquale said the EPA would propose those regulations “relatively soon.” The rules would promote green roofs, tree plantings and other types of low-impact development, which promotes the infiltration and absorption of rainfall to keep it from flowing directly into streams.

Cardin stressed the need for new rules, saying  “construction done in the right way can help us deal with our problems.”

Will Baker, president of the Chesapeake Bay Foundation, agreed that the Bay was getting better but said it was still “out of balance” with plenty of warning signs, such as sharp declines in underwater grasses, as well as large numbers of sick striped bass in the Bay and stressed smallmouth bass in several of its tributaries.

But, after decades of missed deadlines, Baker expressed cautious optimism that cleanup efforts under the TMDL were on track, though he stressed the importance of federal involvement.

“The federal government is the only jurisdiction which can do what scientists say needs to happen — manage this as a single ecosystem,” he said, holding up a map of the Bay watershed, which includes portions of six states and all of the District of Columbia.

Yet much of the cleanup burden has been falling on local governments. Anne Arundel County Executive Laura Neuman testified that her county will spend $250 million to upgrade wastewater treatment plants, $1 billion to reduce stormwater runoff and $1.5 billion to hookup half the 40,000 septic systems in the county to sewers.

She criticized state legislation that required Anne Arundel and nine other Maryland municipalities to impose stormwater fees — often called the “rain tax” — to help fund and maintain stormwater systems. She said the fee has generated “numerous complaints” from ratepayers, and she faulted the state for requiring it without any public education campaign to explain its need.

“Local governments cannot do this alone, nor should we have to,” Neuman said, adding that the “federal government should take the lead” in helping to fund the cleanup.

“The Chesapeake Bay is a national treasure,” she said. “It should be a shared resource and a shared responsibility.”

Baker criticized local government officials for “scaring people” with inflated cost estimates for achieving Chesapeake cleanup goals, saying “the [Bay’s] greatest challenge is having local officials talking about how costly this will be.”

Still, he agreed about the critical need for “sufficient — and consistent — federal funding and technical assistance for stakeholders to defray cleanup costs.”

Cardin said water infrastructure overall was hugely underfunded at the federal level, putting a burden on local governments. “There is a limit to how much you are able to charge the ratepayers,” he said.

Rep. John Sarbanes, D-MD., who joined Cardin at the hearing, agreed. He also said the spending would not only help the Bay, but create jobs, both in implementing cleanup actions, and from a restored Chesapeake. “The Bay is not only an environmental treasure, but an economic catalyst for the fishing and tourism industries, which put thousands of Marylanders to work,” Sarbanes said.