An Oak Bluffs dredging project in a key area of Sengekontacket Pond aimed at improving tidal circulation and reducing bacteria levels in the pond hit a snag last week following the revelation that an Indian artifact may have been found along the shore of the pond.

The artifact is a piece of wood that may be part of an old Wampanoag fishing weir. Although the facts surrounding the discovery are unclear, the piece of wood may have been found during another dredging project on the Edgartown side of the pond last winter.

It is known that the Wampanoag Tribe of Gay Head (Aquinnah) sent a letter to the Army Corps of Engineers — which has final permitting authority over the Oak Bluffs dredging project — informing them of the discovery.

After receiving the letter, the Army Corps promptly granted the tribe a 180-day period to review the artifact, automatically placing the Oak Bluffs dredging project on hold for 180 days.

Oak Bluffs waterways officials had planned to start the dredging project on Oct. 1 and finish it by Jan. 15, the start of winter flounder spawning season when dredging is prohibited. The project calls for dredging a channel between the Big and Little Bridges, removing some 57,000 cubic yards of sand. Oak Bluffs voters approved $500,000 for the project at their annual town meeting in April. The article was placed on the warrant after a petition drive led by shellfisherman Bill Alwardt. The dredge project is being overseen by a joint committee created last year between Oak Bluffs and Edgartown.

Bacteria counts recorded in 2007 by the Division of Marine Fisheries during an annual spot check found high levels of coliform bacteria, automatically triggering a three-year closure for shellfishing from June though September. This past summer marked the third year for the closure, and Marine Fisheries will conduct a new round of testing to determine if the pond can be reopened by next June.

Last winter a major dredging project was completed on the Edgartown side of Sengekontacket, commonly named Anthier’s Pond.

The Oak Bluffs project was expected to complete one leg of a concerted push by an array of public and private groups work to clean up the pond and allow it to be opened for shellfishing year-round again.

But the plans could now be pushed back at least a year with the possible discovery of a piece of an ancient Wampanoag fishing weir. Details about the discovery are sketchy at best; telephone messages left with tribal officials this week were not returned, and town officials remain largely in the dark.

“I just found out [last] Thursday. I can tell you when I heard, I felt like I had been punched in the stomach,” said Oak Bluffs selectman Duncan Ross, who is also chairman of the joint Sengekontacket committee. Mr. Ross said he knows little about the discovery of the artifact except that it was apparently discovered by an unidentified member of the tribe — it is not known when — who then sent a letter to the Army Corps of Engineers, which subsequently decided to grant the 180-day review.

Mr. Ross called the turn of events discouraging. “We made so much progress getting this on track for the fall . . . if the [Army Corps of Engineers] upholds the 180 days, then we lose our window of opportunity and have to wait another year,” he said.

At the selectmen’s meeting on Tuesday, town administrator Michael Dutton said town officials will meet with members of the tribe next week to discuss a compromise that would allow the dredging project to continue.

“I believe the tribe can send a letter [to the Army Corps of Engineers] to try and resolve this. That is my hope . . . I cannot promise that, but my fingers are crossed,” Mr. Dutton said.

Mr. Alwardt, who led the petition drive to put the dredging money on the annual town meeting warrant, noted the pond has been dredged at least three times in recent years, which he said casts doubt on the reported artifact discovery. “They found this over a year ago, now all this time later they are asking to hold us up? They don’t even know what it is,” he said.

Lynn Fraker, former Edgartown dredge administrator and coordinator for the Oak Bluffs dredge project, had similar doubts.

“The chances of it being a historic artifact are minimal. There is so much wood in there already it could be anything,” she said, adding: “When they [Edgartown] dredged the pond last year they came up with lots of stuff . . . and we haven’t even seen it yet, I am curious to see what it looks like,” she said.