On May 23, 2003, a multi-vehicle accident was reported on Interstate 68 at mile post 29, eastbound. When Fire and Rescue Units arrived, they found several vehicles involved in the eastbound accident. Garrett County Sheriff's Dept. Communications Operator Bill Wiltison noted that this accident occurred around 1:20 p.m. Friday; and a second, larger accident, involving more than 50 vehicles, began almost an hour later in the westbound lanes. This second accident quickly turned into a nightmare involving a chain reaction with nearly 90 vehicles, including tractor trailers. Heavy fog was blamed for the accident. Interstate 68 remained closed for approximately 24 hours after the first accident occurred. Fog is a cloud that forms at the surface of the earth. It consists of a multitude of minute water droplets suspended in the atmosphere. According to international definitions, fog is present when horizontal visibility drops below 0.62 miles or one kilometer. Heavy fog is defined as visibility below 0.25 miles. This serious multivehicle accident, the latest in a series of accidents caused by reduced visibility in fog, was the impetus for this investigation into remedial measures can be applied in this fog-prone corridor. The corridor in question extends along I-68 from the West Virginia state line to the vicinity of Frostburg, Maryland, a distance of approximately 35 miles. The objective of this project is to install a system that will identify conditions of low visibility and notify approaching drivers of the limited visibility situation before they encounter it. Following an introduction, this report provides a discussion of similar projects and the technology they employed. With this background, the report examines the project site and identifies fog-prone areas. It then defines sensor locations and traffic sign locations within these areas. The state highway administration (SHA) has an investment in road weather information systems (RWIS) infrastructure in this corridor. The next section identifies key components of this infrastructure. The final section of the report provides a description of various alternative approaches and recommends a specific solution. In this last section, the recommended solution is described in detail and costed.
Abstract