OMAHA (DTN) -- EPA asked a federal court to throw out a handful of lawsuits alleging the agency failed in its legal responsibility to clean up the Chesapeake Bay, in a motion filed on Friday.

Lawsuits filed in the U.S. District Court for the District of Columbia by the Chesapeake Bay Foundation and the states of Maryland, Virginia and Delaware, along with the District of Columbia, argue EPA has failed to hold accountable New York and Pennsylvania for not cutting nutrient runoff as part of the total maximum daily load, or TMDL, program for the bay.

In 2010, EPA issued a TMDL for the Chesapeake Bay and its tributaries with jurisdictions in the District of Columbia, Delaware, Maryland, New York, Pennsylvania, Virginia and West Virginia.

The states adopted caps on discharges of nitrogen, phosphorous and sediment in the bay region.

EPA is tasked to oversee and evaluate progress by each jurisdiction and to act to ensure plans are implemented.

In its court motion, the agency said the plaintiffs have mischaracterized the EPA's authority.

"EPA's evaluations of New York and Pennsylvania's phase three WIPs (watershed implementation plans), which provided the agency's assessment of the states' plans and suggestions for how they could address shortcomings," the agency said in its dismissal motion, "are not final agency actions subject to judicial review. EPA's evaluation of the states' planning documents are informational only, not intended in purpose or effect to be final agency actions. EPA has no authority or obligation to 'approve' the states' WIPs under the Clean Water Act."

Both lawsuits claim the EPA violated the Clean Water Act and the Administrative Procedure Act.

The Chesapeake Bay Foundation said it is concerned about the future of the bay as the lawsuits play out.

"We are disappointed, but not surprised, that EPA continues abdicating its responsibilities under the Clean Water Act," CBF President William C. Baker said in a statement.

"The fate of bay restoration is now in the hands of the court. If EPA doesn't require Pennsylvania and New York to meet the commitments to reduce pollution, the bay and its rivers and streams will never be saved."

The agency argues it does not have the final say on how or whether Chesapeake Bay states implement watershed implementation plans.

"EPA's evaluations are to inform the bay agreement states (and the public) as to their progress and the strengths and shortcomings of their plans," the motion to dismiss said.

"Indeed, both states have committed to revising their WIPs in light of EPA's recommendations. Accordingly, EPA's evaluation and its alleged failure to impose, therein, federal backstop measures is not final for purposes of judicial review."

The Chesapeake Bay Foundation argued in its September 2020 lawsuit EPA's lack of action would lead to the continued degradation of the bay.

In 2014, EPA and the states signed an agreement that requires all practices to be in place to reduce pollution in the bay.

The Chesapeake Bay Foundation, however, said the states of New York and Pennsylvania have come up short and haven't been pressed by EPA. Both states submitted updated plans to EPA in 2019.

The CBF lawsuit said Pennsylvania is responsible for 46% of the nitrogen, 26% of the phosphorus and 31% of the sediment load into the Chesapeake Bay.

Even though EPA has imposed so-called backstop measures by transferring pollution loads from one sector to another, the lawsuit said those measures were "ineffectual" as Pennsylvania did not meet its obligation.

In a separate lawsuit filed the Maryland, Virginia and Delaware, along with the District of Columbia said EPA's approval of New York's and Pennsylvania's TMDL plans were "arbitrary and capricious."

The government plaintiffs said EPA approved Pennsylvania's plan in 2019, although it was proposed to "achieve only 64% of the nitrogen reduction targets prescribed for Pennsylvania by the bay TMDL, and 76% of the phosphorus reduction targets prescribed for Pennsylvania by the bay TMDL."

When New York submitted its plan last year, EPA found it would achieve just 61% of nitrogen-reduction targets.

Todd Neeley can be reached at todd.neeley@dtn.com

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