Scott Bates, chairman of the newly created Connecticut Port Authority, spoke plainly Wednesday in assessing the damage that New York State would cause our region if officials there were successful in blocking plans for the disposal of materials dredged from eastern Long Island Sound.

“The result of their actions, if allowed to run unchecked, would be economic devastation for eastern Connecticut’s shoreline economy,” said Bates, speaking at a news conference held at New London City Pier to show the bipartisan political support in the region in favor of the disposal plan.

Both Democratic and Republican state senators and representatives, as well as local elected leaders of both parties, attended the event, the broadest political support any effort has received since the successful fight to get the Naval Submarine Base in Groton off the Pentagon’s closure list a decade ago. Also attending were Gov. Dannel P. Malloy and Second District Congressman Joe Courtney, both Democrats.

It may well be the most important policy fight since “Save the Base.” Without a local and cost-effective plan for disposing of dredged materials, the submarine base could again become vulnerable to closure efforts, the viability of Electric Boat’s Groton shipyard would be threatened, and New London’s port would fall short of its potential for increased commerce.

The many small private marinas that dot our local coastline, and which must periodically remove sediments to remain in business, could see their business models collapse.

According to information provided at Wednesday’s news conference, these activities generate $4.8 billion in economic input and more than 30,000 jobs in our region, accounting for 92 percent of all navigation-dependent economic activity and jobs in eastern Long Island Sound.

Which is part of the problem. New York State has far less to lose economically if engineers do not adequately develop plans for handling dredged materials in a timely fashion. Because of the currents that carry sediment and the nature of shoreline development over a century, nearly 80 percent of the dredged materials that the Environmental Protection Agency expects will require open-water placement over the next 30 years will come from eastern Connecticut projects.

After many years of study, the EPA recommends the disposal of dredged materials from the region’s harbors, ports and channels at a 1.5-square-mile site between the mouth of the Thames River and the southwestern end of Fishers Island. The new disposal location would replace the nearby Cornfield Shoals dump site and one off Old Saybrook. Those disposal sites have reached their permit limits and must close at the end of December.

But Alphonso David, chief counsel for New York Gov. Andrew M. Cuomo, has said New York is prepared to sue if EPA gives final approval to the plan.

While the proposed disposal location would be in Connecticut waters, it would be near the New York border and in boat traffic lanes. Environmental officials in in New York question its need. They contend the EPA is overestimating how much dredged material will have to be removed over the next three decades, arguing that existing disposal sites in the central and western Sound have the capacity to handle it.

New York officials also argue more can be done to use dredged materials to replenish beaches and for other shoreline uses, reducing disposal needs.

The EPA, however, well documents that a third site is necessary and it does have plans for on-shore uses when possible. The cost of transporting locally dredged materials to the other locations would be prohibitive.

New York authorities also have tossed out the possibility of instead using Niantic Bay if another disposal site is needed, a suggestion that to us makes no sense.

Asked if he had reached out to his Democratic counterpart, Gov. Cuomo, to try to reach a compromise short of litigation, Malloy gave a dodgy answer that amounted to “no.” His environmental people are talking to Cuomo’s environmental people, Malloy explained.

Given the stakes, Malloy should be making a direct appeal to Cuomo. New York’s position is unreasonable. For the good of both states and their relationship, Malloy needs to try to convince Cuomo of that fact.