HD35 - Safety of Vehicular Crossings on the Norfolk and Southern Railroad Under Study for Relocation in the Cities of Chesapeake, Portsmouth, and Suffolk

  • Published: 1989
  • Author: Department of Emergency Services
  • Enabling Authority: House Joint Resolution 162 (Regular Session, 1988)

Executive Summary:
As requested by House Joint Resolution No. 162, passed by the 1988 Session of the General Assembly, the Department of Emergency Services has conducted a safety and hazard analysis of the Norfolk and Southern Railway grade crossings between Gum Road in the City of Chesapeake and Cedar Lane in the City of Portsmouth. An expected accident rate was calculated for each rail crossing using a standard U. S. Department of Transportation mathematical model. Expected accident rates were calculated for each crossing as it now exists and for an upgraded condition of flashing lights and gate guards for both the 1987 observed traffic volumes and the projected 2010 traffic volumes (Tables 4 and 5). These expected accident rates were low and were improved by as much as sixty percent on some crossings by the addition of flashing lights and gate guards.

Using the U.S. Environmental Protection Agency's Technical Guidance for Hazards Analysis risk areas were defined for the hazardous materials currently transported over the existing railroad. This area encompasses a corridor twenty miles wide along the railroad from its juncture with I-664 to the Virginia Chemical facility with a ten mile arc east of Virginia Chemical. Dependent upon the location of an incident releasing one of these hazardous materials, the quantity released, the wind direction, and other atmospheric conditions, a variable number of the estimated 475,000 people located in the defined risk area would be exposed to the risk. A similar risk area was defined for the proposed relocation route. However, due to the geography and demographics of the area, the population at risk from a train related accident would increase rather than decrease.

Similar risk areas were defined using the U. S. Department of Transportation's Guidebook for Initial Response to Hazardous Materials Incidents. This is an area of risk, extending one and one half miles on either side of the transportation routes (See Figure 2), for which immediate decisions must be made for protective actions for the population at risk. There are approximately 34,000 citizens potentially at risk in this area who, dependent upon the conditions described above, would be considered for immediate evacuation. A similar area defined for the proposed relocation route would initially reduce the population at risk from a train related accident by approximately 1,300; however, projected growth in the northern section of the City of Suffolk would soon nullify this advantage. The area at risk from the current transportation of these hazardous materials by truck over U.S. Route 17 closely approximates the risk area defined for the relocation route for the railroad. Upon completion of the Western Freeway, the risk area for hazardous materials transported by truck will be identical to the risk area for the same materials transported by rail if the railroad is relocated.

Relocating the railroad would remove the risk of a railroad crossing accident involving a loaded chemical car and a motor vehicle. This risk, however, would be replaced with the risk of a train derailment on the new route, particularly during the first two to four years after construction, reduced accessibility to the site of a rail accident, and the compounding of the hazardous materials risk by sharing the transportation corridor with other vehicular traffic transporting hazardous materials.

There are three curves within the first one and one half miles of the proposed track which are seven and eight degree curves. Sixty percent of rail buckling, which can cause train derailments, occurs on five to ten degree curves, although this only represents seven percent of the railroad track. In the event that, due to the protected nature of the railroad track in the highway median, train speeds are increased above the five to ten miles per hour at which they now operate it would be reasonable to expect that the likelihood of a tank car being ruptured in a derailment would increase. Highway barriers separating the freeway traffic from the railroad in the median strip would also inhibit access by emergency response personnel and the absence of fire hydrants would limit their ability to combat fires and fumes from hazardous material releases.

In conclusion, relocating the railroad does not necessarily remove the hazard nor does it significantly reduce the population at risk. Potentially it could exchange the probability of a slow speed grade crossing accident for the probability of a higher speed train derailment on one of the curves on the new track, compound the hazardous materials risk along the Western Freeway, and inhibit access by emergency response personnel to the site of a rail accident. For these reasons the hazard reduction realized by the slightly reduced risk of a hazardous materials incident and the elimination of the risk of a grade crossing accident by relocating the railroad are not of sufficient magnitude to justify its relocation at this time. However, it is also clear that any increased growth in the use of the railroad required by industrial development and growth is the I-664 and Western Freeway corridor could alter the risk assessment. Accordingly, the following recommendations are made:

1. Reevaluate the relocation of the railroad to the median of the Western Freeway and I-664 when increased rail transportation required by industrial development and/or other factors clearly changes the current balance of risk in favor of relocation.

2. Provide an alternate access route for residents of the Lilac Road area north of the railroad by a connecting street between the north end of Lilac Road and Moon Road or by extending Lilac Road eastward to Cedar Lane.

3. Further reduce the expected accident rate of the existing crossings by installing lights and gates crossing guards at each crossing.

4. Allocate sufficient space in the median of the Western Freeway and I-664 for construction of the railroad at a future date should it become a necessity.