The tanker that hit three sailboats moored at a yacht club in the Piscataqua River on Wednesday suffered a 3-foot-by-10-foot tear on its starboard bow, the Coast Guard said Thursday.

The 477-foot-long Chem Venus began taking on water Wednesday evening, but the flooding was stabilized by the ship’s crew and is being monitored by the Coast Guard.

Coast Guard Lt. David Bourbeau said salvage divers discovered the damage to the tanker during an inspection Thursday afternoon.

The owners of the Panamanian-flagged tanker are expected to develop a salvage plan that will be reviewed and approved by the Coast Guard.

The Chem Venus will remain anchored outside the mouth of the Piscataqua River, near Kittery and Portsmouth, for an indefinite period.

No one was injured in the collision and the river was not polluted.

The Chem Venus was transporting used vegetable oil and various industrial chemicals when it ran aground on Goat Island Ledge and drifted into the sailboats, which were not occupied.

Bourbeau said the ship’s captain and some members of the 22-person crew were tested for drug and alcohol use. Only crew members involved in the navigation aspect of the voyage were tested. Alcohol testing must be done within two hours and drug testing within 32 hours.

Bourbeau was unable to provide the name of the captain, but said the ship is owned by Chem Venus SA. Its managing partner is Fleet Management Limited.

The Coast Guard has not determined a cause yet.

“We have no root cause at this time,” Bourbeau said Thursday evening. “For those people who are looking for reasons as to why this happened, it’s too early to say. But if negligence is determined to be a factor, the captain and crew could face penalties.”

The three sailboats were moored at the Kittery Point Yacht Club in New Castle, New Hampshire. The Piscataqua River forms the boundary between Maine and New Hampshire.

“We are extremely fortunate this incident did not result in environmental pollution or loss of life. We continue to monitor this situation very closely in coordination with our federal, state and local partners,” Coast Guard Capt. Michael Baroody said in a news release. “Our priority moving forward is to ensure a safe and effective salvage plan is developed that allows for the vessel to be safely moved to a facility capable of making necessary repairs.”

The Chem Venus was being escorted toward the ocean by two tugboats when its captain and crew failed to make a sharp turn near Henderson Point. The tanker ran aground on the ledge before hitting the sailboats, according to an eyewitness.

Glenn Kisch, who lives on Goat Island, said dozens of ships traverse the river weekly without any difficulty, so he was surprised when the tanker missed the turn.

The tanker was bound for Teesport, a large seaport in northern England.

Dennis Hoey can be contacted at 791-6365 or at:

dhoey@pressherald.com