When television production company 44 Blue wanted to find an expert in the design of safe emergency escape ramps producers went to the Institute of Transportation Engineers, which in turn summoned retired ITD engineer Jim Pline.
No one better to explain how to design and build escape ramps than Pline, who left the department in 1987 after serving 35 years in a variety of roles. In his new life as a private engineering consultant, Pline has helped clients with traffic studies and has traveled nationwide as an expert witness in legal cases.
His call to be an expert in escape ramp design was a first.
Producers this week met with Pline on a snow-covered hill above Horseshoe Bend to look at one of about two-dozen ramps in Idaho. After a local independent film crew documented their conversation, the entourage returned to ITD Headquarters for several hours of interviews in the department’s video studio.
The final product will air soon on the Discovery Channel, carried on many cable television and satellite systems. It will air as part of “Survive This,” a series dedicated to individuals who were involved in near-death events and lived to tell about it. The intent, explains Pline, is to look at how the victim survived and what can be done in the future to prevent similar circumstances.
Impetus for the segment on escape ramps came from a truck driver who plowed through an escape ramp in Pennsylvania and survived a violent crash. Through past contacts, officials from the Institute of Transportation Engineers knew Pline was involved in designing and building Idaho’s ramps.
States in the Northwest were among the first to use ramps – short lanes of gravel that run parallel to the main highway on steep grades – to slow trucks that experienced brake failure or other mechanical problems. Truck drivers pull off the highway and onto the ramps where they are slowed and eventually stopped by a bed of gravel.
Most of the ramps, explains Pline, are between 1,200 and 1,500 feet long and take into account both the severity of the incline and location on the grade. Many of the escape ramps follow the same grade; others will carry runaway trucks back up an incline, using both gravel and gravity to bring it to a stop.
Pea gravel, so named because it is round and smooth, is placed to a depth of 18 to 24 inches. The material is chosen because it does not compact like gravel chips or become hard when wet like sand.
ITD began replacing sand on escape ramps with gravel in the late 1970s, Pline said. The first ramp built in Idaho was on the U.S. 95 Bonners Ferry grade. The ramps are scattered throughout the state, with the largest concentration on the Lewiston grade north of Lewiston and on the White Bird grade between Grangeville and Riggins.
The ramps are designed so the weight of the load – not the truck – gradually sinks into the gravel, functioning as an anchor. Choosing the wrong type of gravel can bring the truck to an abrupt stop and jack-knife the trailer. Pline explains that it is not uncommon for a trailer to become buried up to its axle in the gravel.
Escape ramps are used most frequently because of over-heated or inadequate brakes and by drivers who do not shift into a lower gear early enough on the grade.
Pline, 75, was a project development engineer at ITD when he retired. In his 35 years with the department he also was an engineer-in-training and assistant district engineer in District 4. He spent 10 years as a traffic engineer and also worked in environmental and corridor planning.
He graduated from the University of Idaho with a civil engineering degree in 1954 and four years later earned a certificate in traffic engineering from Yale University. He also holds a master’s degree in public administration.
In all, he has more than 50 years of experience in transportation.