Police say a Lake Grove man died Monday after he accidentally drove his SUV down the Port Jefferson boat launch and into the water. 

Officers rushed to the Port Jefferson Marina just after 7 p.m. Monday after witnesses saw the car roll into the water.

William Whalen, 69, was trapped in the car, which was completely submerged. 

The incident marks the fifth time someone has driven into the harbor in recent years and the second fatal accident at the boat launch in the past six months. 

Village Mayor Margot Garant says part of the problem is the confusing intersection across the street from the marina. That intersection has a traffic signal that shows a solid green light crossing over Route 25A. However, the other side of the street has a "Do Not Enter" sign and nowhere to go – except down that boat ramp and right into the water.

Garant says the green light should be changed to green arrows in each direction. 

In a letter to the mayor's office last month, the state Department of Transportation said they plan to make that change, though it's unclear when that will happen.

In April, a man was rescued from his car after it went underwater in a similar fashion. In 2016, a woman was saved after she drove down the boat ramp. Similar accidents in 2012 and 2005 were fatal.