WASHINGTON — Hundreds of interstate highway fatalities have been prevented in multiple states by relatively inexpensive safety devices that were not in place at the site of a fiery bus-truck collision last week in California that killed 10 people.
While interstates are statistically the countrys safest roadways, theyre also vulnerable to one of the deadliest kinds of crashes, where one vehicle crosses the median at a high speed and strikes another traveling the opposite direction.
At a time when states are pinching their transportation pennies, the installation of steel cable median barriers has helped states improve highway safety without a lot of investment.
Its very effective at capturing the vehicle, said John Miller, a traffic safety engineer with the Missouri Department of Transportation. Weve seen a lot of great benefit from it.
On April 10, a FedEx double-trailer truck crossed from the southbound to the northbound lanes of Interstate 5 in Orland, Calif., slamming into a motor coach that was taking a group of Los Angeles-area high school students on a visit to Humboldt State University.
The drivers of the two vehicles, five students and three chaperones were killed. Some victims were thrown from the bus, while others died in the ensuing fire. The National Transportation Safety Board is investigating the crash.
More than 300 fatal cross-median crashes happened on interstate highways in 2012, according to data from the National Highway Traffic Safety Administration.
Despite improved highway safety in states that have installed barriers along rural interstates in recent years, the federal government doesnt require them in the medians of divided highways. Missouri and North Carolina, which have installed the barriers on parts or all of their interstate highways, have seen cross-median fatalities cut by as much as 90 percent. Others, such as Kentucky, are in the process of installing more.
The widespread deployment of cable barrier in recent years has, in my opinion, saved many lives in our country, said John Njord, who was Utahs transportation secretary from 2001 to 2012.
At the location of last weeks deadly collision, the highway median lacks a steel cable barrier, which is designed to prevent regular-size cars and trucks from crossing into oncoming traffic. Though theyre not designed to stop heavy trucks, they often do.
The left shoulders of the California roadway also are equipped with rumble strips, grooves in the pavement that warn drivers when they start to veer off the roadway because of distraction or drowsiness. The Federal Highway Administration recommends rumble strips on the left and right shoulders of divided highways, citing a study that showed vehicles were just as likely to veer left off the road as right.
The California Department of Transportation said last weeks crash site didnt meet its requirements for installing median barriers, which include frequency of cross-median crashes, the width of the median and the daily average traffic count.
Caltrans spokesman Mark Dinger said that only one similar crash had taken place within two miles of the site within four years, below the level that would indicate a recurring problem. But he added that the agency wouldnt rule out making changes.
Median barriers and rumble strips have been used for years to prevent crashes where cars and trucks leave the roadway, especially along urban freeways with higher traffic volumes.
The standards have evolved. Early in the interstate system, a barrier was recommended in medians that were 30 feet wide or less. Now the American Association of State Highway and Transportation Officials recommends them in medians of 50 feet or narrower. The Interstate 5 median at last weeks crash site is 58 feet.
Other states have set higher standards. Missouri and South Carolina have decided that barriers are appropriate for median widths of 60 feet or less. North Carolinas standard is 70 feet.
Some highway safety advocates think that every median needs protection.
The ideal would be to have some kind of barrier along all the interstates, said Henry Jasny, vice president and general counsel for Advocates for Highway and Auto Safety.
Before interstate highways were constructed, the nationwide highway fatality rate was more than five per 100 million vehicle miles traveled. In 2010, the rate had declined to 1.1, and interstate highways boast an even lower rate.
However, the oldest parts of the 47,000-mile network, built 40 or 50 years ago, are still largely four-lane divided highways with open medians. When the roads were new and traffic was light, it might have been possible for a car to cross into opposing lanes and not collide with another vehicle.
But as traffic has increased, the chances of a collision have risen. That vehicle is now more likely to be a heavy truck, and the crash is more likely to include multiple fatalities. And drivers have a new source of distraction: cellphones.
The section of Interstate 5 near last weeks crash handles about 24,000 cars a day, according to Caltrans, making it one of the least traveled segments of the highway in California.
That segment also sees 5,000 heavy trucks a day. Interstate 5 is the primary north-south highway along the West Coast, and truck traffic is projected to increase in the coming decades.
The California highways rural character, traffic volume and median widths are comparable to the western half of Interstate 70 in Missouri, which has a cable median barrier and rumble strips on the left shoulders.
Missouri estimates that it may have saved 300 lives since it began installing cable barriers in the medians of its interstates more than a decade ago. The state now has 800 miles of median barriers, including the entire length of Interstates 70 and 44, two of Missouris busiest roadways.
Steel cable barriers might cost $40,000 to $50,000 a mile, versus 10 times that much for concrete. Rumble strips can be installed for as little as $1,500 a mile, Miller said.
Theyre almost dirt cheap, he said.
But they cant stop every fatal crash.
In March 2010, the driver of a tractor-trailer, fatigued and talking on his cellphone in the early morning, veered off the southbound lanes of Interstate 65 in Kentucky. The truck sailed over a rumble strip and a cable median barrier, right into the northbound lanes. It is struck a passenger van that was carrying members of a Mennonite family from southern Kentucky. The truck driver and 10 passengers in the van were killed. Only two small children survived.
When the truck hit the cable median barrier, said Mike Hancock, the states transportation secretary, it was barely slowed down by it.
Still, Hancock said, the barriers have prevented countless fatal crashes, and the state continues to install them.
Kentucky is also giving its busiest interstates the ultimate makeover, widening them from four lanes to six, with concrete median barriers that can stop a truck.
Weve understood for quite some time that its the best improvement we can do, Hancock said.
The NTSB recommended after the Kentucky crash that the U.S. Department of Transportation develop better guidelines on where to install median barriers, and what kind. It also asked the department to consider heavy truck volumes in barrier selection.
The agency, which has no enforcement authority, also asked the DOT to come up with a standard definition of what constitutes a cross-median crash. Four years later, there still is no such category of accidents in the departments highway fatality database.
The absence of consistent data on cross-median crashes makes it more difficult for states to determine where barriers are necessary. Most dont have the funding to simply put them in every median.
Under ideal conditions, every segment of the interstate would have every safety apparatus for every eventuality, Njord said. That is not the real world.
Correction: This story originally incorrectly stated that the site of an April 10 fatal bus crash in California lacked left-shoulder rumble strips. The California Department of Transportation initially told McClatchy that the road did not have the left rumble strips, but it later said they were installed there in 1994.