But the agency did not call for any new actions against the states, although their shortfalls — especially Pennsylvania’s huge gap — means the region would miss its 2025 deadline to put in place all actions needed to achieve the Bay’s clean water goals.

Instead, the agency asked the states to provide more details about the actions they would take during the next two years to get their programs back on track.

Meanwhile, the EPA’s evaluation of other state plans, which were submitted in August, found that they met goals, though the review found that most needed more detail to show how they would achieve the dramatically ramped-up rates of action needed to curb polluted runoff from farms and developed lands. The District of Columbia, though, has met its goals.

The EPA in 2010 established a new cleanup program called the Chesapeake Bay total maximum daily load, or “pollution diet,” which set limits on the amount of nitrogen and phosphorus that each state sends to the Bay. The nutrients spur algae blooms that cloud its water and fuel oxygen-starved “dead zones.”

Since then, the levels of the water-fouling nutrients have declined — and phosphorus goals likely will be met — but the region remains far off track for nitrogen. Nitrogen reductions are lagging mostly because of shortfalls in Pennsylvania, which is, by far, the largest source of nutrients reaching the Chesapeake, though it does not border the Bay.

The EPA required the new state cleanup plans to show how states will meet nutrient reduction goals by the TMDL’s 2025 deadline. Between now and then, states also must continue to submit additional plans showing the actions they will take in two-year increments to show they are making adequate progress.

“It is critical that we continue the momentum that has led to signature successes and positive signs of resilience in the watershed,” said EPA Regional Administrator Cosmo Servidio. “The Chesapeake Bay is a national treasure and its environmental, economic and cultural importance cannot be understated.”

But the agency’s failure to announce any actions against Pennsylvania — whose plan fell 25% short of its nitrogen reduction goal and had an annual funding shortfall of more than $300 million a year— was a disappointment to some.

“EPA has failed to fulfill its obligation to be the referee of the multi-state partnership. It has not held Pennsylvania accountable,” said William Baker, president of the Chesapeake Bay Foundation. “Rather, it has once again kicked the can down the road, abdicating its Clean Water Act responsibilities and putting the Bay restoration in jeopardy.”

He said the environmental group was considering suing the EPA for not using its regulatory oversight authority to enforce cleanup goals.

The agency has the ability to take a variety of actions against states failing to meet their goals, such as increasing oversight, extending regulatory authority over more entities, and requiring more pollution reductions from dischargers with permits, such as wastewater treatment plants.

In its evaluation, though, the EPA focused on providing assistance rather than meting out punitive measures, pledging to provide Pennsylvania with more technical support, continued grant funding, and help identifying places where runoff control measures would be most effective in meeting Bay goals.

As written, Pennsylvania’s plan would be about 9 million pounds short of its nitrogen reduction goal. New York’s plan was about 1 million pounds a year short.

That gap is more than a fifth of the 47 million pounds of additional annual nitrogen reductions the region needs to achieve to meet Bay water quality goals.

Most of the nitrogen reaching the Bay from Pennsylvania — and all of it coming from New York —flows down the Susquehanna River, the Bay’s largest tributary. Nutrients from the river, which empties near the head of the Bay, have an enormous impact on the Chesapeake’s water quality. Failure to come close to meeting nitrogen goals in the Susquehanna means that most of the Bay would be unlikely to meet clean water objectives.

Achieving nutrient reductions in Pennsylvania has been a struggle because most of its nitrogen comes from agriculture and stormwater runoff — sectors that all Bay states grapple to control. Pennsylvania has far more farms — 33,000 — than the other states, though, and most are small, making both oversight and outreach difficult.

Maryland, Virginia and the District of Columbia have made progress largely because they have reduced nutrient discharges from large wastewater treatment plants, and Pennsylvania has few of them. Since the TMDL was established, 85% of the nitrogen reductions in the Bay watershed have come from upgrading wastewater treatment plants across the region. But there are few plants left that need upgrades.

All states must now significantly ramp up efforts to control runoff from farms and developed lands at rates far beyond what they have demonstrated they can achieve in recent years. From now to the end of 2025, state plans cumulatively call for about 82% of the remaining nitrogen reductions to come from agriculture and 5% from developed lands.

While plans from other states generally described programs that would reach their goals, the EPA said more details are needed to boost confidence in that outcome. Its analysis said that states should provide estimates about the number of on-the-ground nutrient control actions they plan to take during the next two years.

In some cases, state plans call for the implementation rates of runoff control practices to be increased tenfold beyond recent levels. In comments submitted earlier this year about state plans, many local governments and conservation districts expressed skepticism that such an aggressive ramp-up could be achieved.