Some big Navy hovercraft got a little too close for comfort for some at the Kaneohe Bay sandbar Monday.

Three of the craft kicked up cascades of sand and water and raised environmental concerns at the popular destination for boaters.

But the director of the state Department of Land and Natural Resources said the reports he received — including from a DLNR harbor agent on site — indicated there was not "a huge environmental impact."

The shallow-draft vessels wouldn’t have physically affected coral, said William Aila Jr., adding that he is not aware of any threatened or endangered species in that area.

Environmental activist Carroll Cox said he received phone calls about the hovercraft "churning up coral and everything else."

The craft, participating in the Rim of the Pacific naval maneuvers, are known as "landing craft, air cushion," or LCACs (EHL-kaks).

"There were three LCACs, and they were right there on top of the sandbar, and the people were just concerned about the impact on the fish and coral," Cox said.

But Aila said the Navy craft were not on Ahu o Laka, known by most people as the Kaneohe sandbar.

"They were well down south of that," Aila said. "It would be right at the edge of the area that we consider the sandbar for the enforcement of the emergency rules." The rules set up a safety zone around the area, a popular anchorage on weekends.

The LCACs, nearly 88 feet long and 47 feet wide and capable of carrying 60 to 75 tons, are used by the Navy and Marines to transport equipment and troops ashore.

The hovercraft, operating off the amphibious assault ship USS Essex, were near the sandbar as Marine Corps amphibious assault vehicles operated at Pyramid Rock at the Kaneohe Bay Marine Corps base.

Aila said he was told the assault vehicles load up first at the Essex, so the hovercraft had to wait. The breakdown of an assault vehicle also lengthened the wait time, he said.

No notice was given to the DLNR that the LCACs would be operating near the sandbar.

"They didn’t need to give notice because they weren’t conducting any military exercises (there)," Aila said of the LCACs. "They were just told to go hang out somewhere, and they chose to hang out in that area."