“A lawsuit over dredging may not be the spiciest of editorial topics, but this was a big deal.”

So said The Day’s editorial of July 21, 2020, when a federal district court judge ruled against efforts by New York State to prevent disposal of dredged material from the Thames River in nearby waters of Long Island Sound.

It was and is a big deal, because the loss of a practicable disposal site would have threatened the launching and access of submarines from Electric Boat and the Navy base to the sound and the Atlantic. In the opinion of the Army Corps of Engineers, loss of the ability to dredge would have “eliminated” the capacity of the river for submarines. It would have affected the interstate ferries and other maritime traffic that keep the Thames a busy river and an active port.

So it is an even bigger deal this week that a federal Appellate Court ruled in favor of Connecticut and the U.S. Environmental Protection Agency and against New York’s appeal of the two-year-old decision.

Our earlier editorial urged then-Gov. Andrew Cuomo to recognize that an appeal would likely fail, based on the details in the ruling by Judge Edward R. Korman in the Eastern District of New York. Cuomo went ahead with the now-rejected appeal, but New York has moved on from Gov. Cuomo. We urge the administration of Gov. Kathy Hochul to acknowledge that the Appellate Court should have the last word, after several years of litigation and prior decades of interstate negotiations.

The stakes are even higher for Connecticut than they were in 2018, when the state Bond Commission authorized giving Electric Boat $20 million for dredging. A Columbia-class submarine building program is now underway at EB and a wind power assembly facility is under construction at State Pier.

If the Thames were not the significant deepwater port that it is, the submarine base and the submarine builder would not be here, and the wind power assembly facility would not be coming. For them to remain, with their tens of thousands of jobs and high impact on the Connecticut economy, they require a reliably navigable path to the open ocean.

But in addition to its economic importance, the Thames is a resource of great beauty, history and biodiversity. It sustained and shaped the identities of the indigenous tribes and helps define contemporary southeastern Connecticut’s three largest communities -- New London, Groton and Norwich.

Accordingly, both before and after New York took the EPA and Connecticut to court, the federal and state partners took steps to safeguard the cleanliness of the river and the sound and to mitigate the effects of dredging. The EPA reduced the planned 1.3-square-mile Eastern Long Island Sound Disposal Site in size and capacity and sited it entirely in Connecticut waters. It will receive no more than 20 million cubic yards of sediment, a mighty volume but substantially less than the originally planned 27 million.

Materials will be tested for contaminants, and if they pass Connecticut’s water quality standards, can go by barge to the disposal site that was the focus of the case. A fraction of the clean, dredged materials will become fill to shore up beaches and salt marshes against coastal erosion. Any contaminated silt will be treated as a hazardous material.

As opposed to New York’s argument that sites in western Long Island Sound could have served the purpose, use of the eastern site off the mouth of the Thames will be less costly for the base, the shipyard and the smaller businesses that depend on dredging to keep access to deep water. A sound plan that lowers the cost of doing business responsibly is welcome.

With the upholding of the original court finding that the EPA had based its findings on evidence and followed its legal obligations, the agency should be free to complete its site management and monitoring plans. The delay was long and costly, but if there is a benefit from defending the plan in court, it is that an impartial review has meant more opportunity for the public to appreciate what’s at stake.