ANTIOCH — Two people died and another was seriously injured Tuesday afternoon in a head-on collision between a motorcycle and a car on the Highway 4 bypass.
The crash took place at 4:40 p.m. just west of Lone Tree Way, California Highway Patrol Officer Tom Maguire said.
A silver 1995 Honda Civic was traveling west when a black Ford F-250 towing a wakeboard-style boat swerved into the Civic's lane, Maguire said. The driver of the Civic, a 19-year-old Antioch woman, was forced to cross the double-yellow line, directly into the path of a 2000 Harley-Davidson motorcycle that was traveling east.
The male driver of the blue Harley-Davidson died at the crash site. A female passenger was thrown from the motorcycle and later died at an Antioch hospital. The driver of the Civic had serious leg injuries, but her condition is not considered life-threatening.
The CHP was searching for the driver of the Ford and is investigating the crash as a "non-contact hit-and-run," Maguire said.
"We really want to talk to them," he said.
The identities of the victims were not available late Tuesday.
This was the fourth fatality and the second in two months on the bypass between Antioch and Brentwood since it began opening in stages eight years ago. Originally hailed as a saving grace for road-weary drivers, the bypass has drawn criticism from motorists who find parts of it congested and unsafe.
At least 178 accidents have occurred along the portion of the route from the Highway 160 flyover south to the beginning of Vasco Road.
The State Route 4 Bypass Authority plans to widen the segment between Lone Tree Way and Balfour Road from two to four lanes, which observers think would significantly reduce gridlock in both directions during peak commute hours.
Of the 47 collisions that the CHP handled on the bypass during a roughly two-year period ending April 11, excessive speed was the primary factor in 14.
Anyone with information about Tuesday's crash can call 1-800-TELL-CHP or 925-646-4980.
Staff writer Rowena Coetsee contributed to this story. Roman Gokhman covers public safety. Contact him at 925-945-4780. Follow him at Twitter.com/RomiTheWriter.