Rockland County (N.Y.) investigators today began piecing together the specifics of an accident on the Hudson River this weekend that left two dead after a 21-foot powerboat slammed into an anchored barge.

A bride-to-be and the groom’s best man died in the crash, which occurred at 10:40 p.m. Friday when the Stingray runabout hit the anchored and lit barge just south of the Tappan Zee Bridge about 25 miles north of New York City.

Lindsey Stewart, 30, and Brian Bond, 35, were to be married Aug. 10. Stewart’s body was found Saturday morning. The best man, Mark Lennon, 30, was found Sunday morning. Bond was injured in the accident.

“Up until now we’ve been focused totally on the recovery of the bodies,” Rockland County Sheriff’s Department police chief William Barbera told Soundings on Monday morning. “Today we begin everything else.”

Stewart and Lennon were seated in the open bow and were ejected upon impact, Barbera said. They were not wearing life jackets when their bodies were recovered, he said.

All six people aboard the boat were friends, Barbera said. They were on a short trip across the Hudson from Piermont, on the west bank of the river, to Tarrytown, he said.

Click play for a report on the crash.

Police suspect Jojo K. John, the 35-year-old driver, was intoxicated and they charged him with one count of vehicular manslaughter and three counts of vehicular assault, Barbera said. He’ll likely be charged with a second count of vehicular manslaughter now that Lennon has been found, Barbera said.

“Unfortunately, there’s no real mystery here,” Barbera said. “You have young people out celebrating an upcoming memorable event and having a good time. Any time you go on a river at night it is dangerous in itself.”

Recent rainy weather “threw everything but the kitchen sink into that river,” Barbera added. “And, of course, it was a very dark night. If you add intoxication or lack of boating skills or other factors, it becomes extremely dangerous.”

In addition to the lights on the barge, John had to cope with the lighting on the bridge and the lights of Tarrytown on shore. The barge is being used in the construction of a new Tappan Zee Bridge.

Interviews with the survivors led investigators to believe John was under the influence of alcohol. No alcohol was found on the boat, Barbera said. The boat’s owner was not on board. The name of the owner, the boat’s speed, the model year of the Stingray and whether John had boating experience are part of the investigation, Barbera said.

The driver’s blood test results are expected in “a few weeks,” Barbera said.

Photos of the boat in the slings of a marine lift show its damaged bow.

John was in critical condition and was unable to speak to police. Bond and the two other passengers, who also were injured, are expected to recover.

Four Rockland County investigators are working the case, Barbera said. The Coast Guard is collecting information about the barge and its role in the accident, he said.