Driver still missing after truck plunged into Chesapeake Bay. Searchers hope specialized sonar will help.

Robyn Sidersky, The Virginian-Pilot

Searchers from outside the area are coming to deploy specialized equipment they hope will find the body of Erik Mezick, the Maryland truck driver who plunged off the Chesapeake Bay Bridge-Tunnel more than two weeks ago.

On Friday and Saturday, the Charles County Dive Rescue team from Maryland will use a side-scan sonar to search for Mezick in the area where his truck went into the Bay.

The equipment sends out sound waves, which will echo off objects on the bottom of the bay and bounce back, creating an image of what’s down there.

The sonar will be towed by a boat going about 3 mph and scan 100-foot-wide swaths at a time, said team member William “Skeeter” Porter.

Porter is optimistic about finding Mezick. Last year, his team recovered five drowning victims. He usually conducts searches in the Patuxant and Potomac rivers, but the bay isn’t new territory for him.

“We have good information in this case because it was a witnessed event, so hopefully we will be able to get down there and affect a positive outcome,” he said.

Eyewitnesses saw exactly where Mezick landed in the water and where he first drifted. And though the bay has powerful currents, Porter says experience has taught him that bodies that sink in cold water tend to stay near where they went down.

Water temperature and depth are part of the equation.

Porter’s team will run patterns, follow a drift line and then turn back — sort of like a lawn mower, combing the bottom of the bay.

But it’s easier to search if there isn’t other boat traffic around, so the team is asking recreational boaters to steer clear of the area both days. Boats create air bubbles, which appear on the sonar like a cloud and make it harder to see.

Mezick went overboard near mile marker 14 on the northbound span. In that area, there isn’t likely to be other traffic, such as container ships, interfering with the search. Porter’s team typically does about five such searches each year. His organization is structured like a volunteer fire department would be, he said.

They don’t seek out missions, but help if they’re asked and think they can.

“Our team has been fortunate to have become efficient with this equipment,” he said. “A lot of organizations have this same technology but don’t get to spend as much time using it.”

Using side-scan sonar cuts down on risks for divers as well, he said. Divers, already on the boat, aren’t sent down until something of interest is spotted. Their success rate is about 80%, Porter said.

“We do our best,” he said, “but there’s times where something just doesn’t want to get found.”

Robyn Sidersky, 757-222-5117, robyn.sidersky@pilotonline.com