Roundabout considered for Highway 190

Caltrans officials on Thursday confirmed there are plans to build either a roundabout or install a traffic signal at Road 284 and Highway 190.

The intersection was the scene of a triple-fatal crash less than a week ago when a sedan that was southbound on Road 284 failed to stop for the posted stop sign and collided with a pickup truck that was westbound on Highway 190.

Emad Abi-Rached, assistant project manager with Caltrans’ District 6, said the intersection is being considered for one of the two proposed projects because it has experienced an accident rate that is more than three times that of similar intersections on state highways.

He said a roundabout, like a traffic signal, is considered a feasible solution and noted that modern roundabouts have been proven to be a highly-effective type of intersection control, with many advantages over traffic signals, “including lower accident rates, reduced accident severity, less delay, and lower operational costs.”

Added Abi-Rached, “A federal study in 2007 showed that for nine signalized intersections converted to roundabouts resulted in a total accident rate reduction of 48 percent and an injury accident-rate reduction of 78 percent.”

California Highway Patrol Officer Stefanie Buck said the intersection has seen a total of 10 collisions since 1997, when the Porterville-area CHP office began using its current data-collection system. Five of those were injury collisions, with a total of 12 persons injured, and the five others were property damage collisions.

Buck said that in her 10 years with the local CHP office, she could not recall any other fatalities at that particular intersection.

“I don’t remember that being a very problematic area for us. When I was working the road, I was on that beat quite often and I can’t remember getting called out for anything at that specific intersection,” she said.     

She said a roundabout at Road 284 and Highway 190 will be “interesting.”

“They are going to have to lower the speed limit in that area because you can’t come into a roundabout at 55 mph,” Buck said, adding that this is the first time she’s heard of a roundabout on a state highway.

Abi-Rached said roundabouts are becoming more common on the state highway system, with 13 currently operating throughout the state and many more being designed. He said the number is expected to double within two years and that there are six active roundabout projects on the state highway system within the Central Valley.

The project is still in the project approval and environmental document phase, when the preferred alternative is selected and the project is environmentally cleared.

“The preferred alternative has not been finalized yet. Forecasts and computer modeling show that the roundabout alternative would actually yield less delay and shorter queue lengths than that of the signalization alternative,” Abi-Rached said.

He said that cost-estimates for both alternatives have been prepared and that both projects would have an escalated right-of-way cost of $370,000. The construction cost of the roundabout is estimated at $1.3 million and $1.8 million for construction of the traffic signal.

The project schedule shows that construction contract approval is set for February 2014 and the project should break ground in the spring or summer of that same year, Abi-Rached said.

Contact Denise Madrid at 784-5000, Ext. 1047. Follow her on Twitter @DeniseMadrid_.