CHESAPEAKE BAY BRIDGE-TUNNEL, Va. (AP) -- With 800 miles in the rear view mirror, Clay Backus paid the $12 toll, rolled up his window against the raw wee hours and headed north across the bridge.
There was no time to detour to his parents' place in Suffolk. Backus, 25, was making tracks from grad school in Florida to see his newborn daughter in Maryland.
He rubbed his weary eyes: 3 a.m., March 4, only a few more hours to go.
The red tail lights of a lone 18-wheeler, his only company on the span, winked in the distance.
Backus dipped into the first tunnel, a whoosh of bright lights, then back up to the blackness. The tractor-trailer was still there, about a quarter-mile ahead. A panorama of rugged beauty stretched all around, milky foam, half moon, clouds of ink. The second tunnel came and went. Lights glittered on the high-rise section of the bridge ahead, an arch of diamonds spilling onto the Eastern Shore. A bend just before the rise swallowed the 18-wheeler's tail lights.
Suddenly, a volcano of sparks erupted from the curve. Then a huge fireball shot skyward.
''My first thought was terrorists,'' Backus recalled in a recent interview. ''I thought someone had blown up the bridge.''
Experience as a paramedic, much of it in the Bennetts Creek area of Suffolk, sent Backus racing toward the explosion. He skidded to a stop around the 14-mile marker, where a wall of flames raged across both lanes.
The blinding blaze died quickly, leaving scattered pools of glowing orange. Backus recalled the bite of wintry wind after the warmth of his pickup, the hiss of flames as he picked his way through the rubble.
At some point, he realized that the bridge was intact, that spilled fuel had ignited, that something terrible had happened to the trucker in front of him.
His eyes jerked toward the right-hand guardrail, where mangled metal ended abruptly, leaving a gaping hole 250 feet long. There was no sign of the truck.
Backus ran toward the broken concrete curb, slipping on splattered fluids. He groped his way to the far end of the gap, where the twisted guardrail resumed.
Hanging on, he leaned over the windswept edge, clicking on his flashlight. The beam fell on coiling whitecaps surging between the bridge's pilings.
Over there: air bubbles, a cascade making its way to the surface.
''Is anybody down there?'' Backus screamed. ''Can anybody hear me?''
Over and over, he shouted into the vastness.
''Can you hear me? Are you down there?''
Only the wind and waves replied.
At Chief Clement Pruitt's house in Cape Charles, the phone rang around 3:45 a.m. The sound was instantly recognized as bad news.
With 40 years on the bridge-tunnel police force, Pruitt has been around for almost every tragedy since the 17-mile span opened in 1964. Vehicles have collided head on, punched through the guardrails, or gone airborne over the barrier without a brush. There had been too many funerals, 73 so far.
The last time a semi went over the side was in 1995, when a truck topped the high-rise section, came upon a back-up and speared through the rail. Its driver didn't survive the 75-foot fall.
Chances are better at the 14-mile marker, where the bridge stands just 30 feet above the water. But with water temperatures hovering around 40 degrees in early March, Pruitt knew the fall could be the least of this trucker's problems.
''You don't last long in there this time of year,'' he said.
It took 10 minutes for Pruitt to reach his office on the north end of the bridge-tunnel. By 4 a.m., the cavalry had been alerted: Coast Guard, marine patrol, police divers, fire fighters and salvagers.
Across Hampton Roads, nearly 70 rescue workers climbed from warm beds. Boats and helicopters began beating their way toward the bridge.
Backus' account of the fire had Pruitt especially worried. Unlike gasoline, the diesel fuel powering big rigs is slow to ignite. Did a car get entangled with the truck?
''Are there two people down there?'' Pruitt fretted. ''Or even more?''
It's not unusual for Lt. Cmdr. Rich Condit to get three or four calls in the middle of the night. But this one snapped him upright.
''Good morning, sir,'' said his operations officer. ''We have a big one.''
Condit, in charge of local Coast Guard rescue operations, tiptoed downstairs with the portable so as not to wake his wife and children. Within minutes, he was dressed and heading out of his Chesapeake neighborhood for the Coast Guard base in Portsmouth.
Station antenna had already blasted a civilian SOS. Time was of the essence, and the crash scene was remote. Maybe a die-hard fisherman was out there, angling under the bridge. The spot is so popular during certain seasons that ''you can almost walk from boat to boat,'' Condit said.
But on this night, the fishing grounds were apparently deserted. No one responded on the radio.
Condit focused on figuring out who went down. Age, size and health are vital elements of the survival equation. Lives would be risked in the search. Condit needed to know when to call it quits.
Advice came from a computer program designed to calculate survival odds. Given the bitter conditions under the bridge, a typical 30-year-old, 180-pound man wouldn't last more than 2