Johann F. Szautner, D.I.,P.E.,P.L.S. ::::
Case Synopsis: For motorcyclists, nothing beats a leisurely ride on a warm, sunny, spring day, especially after enduring a long frigid winter. On such a spring day, a group of friends went joy riding to experience the open road in the countryside, returning home to the city in the evening . They traveled back on the freeway to a part of the city where their favorite watering hole was located. By now it was late evening. Street lights, which are there to help with a driver’s visibility, were on, but they are often too dim, or broken, and provide only marginal illumination of the roadways.
At some point, the lead driver saw a manhole lid in the middle of his lane and tried to avoid it by passing to the right in the available space between the lid and the parking lane marking, which was 3 feet wide. He did not see that a chunk of pavement was missing, creating a hole of sufficient width and depth to snag the front tire, throwing him over the handle bars. As a result, he suffered multiple injuries, but his life was spared because he was wearing a helmet and protective motorcycle garb.
Engineering Analysis: The missing chunk of pavement, often referred to as a pothole, is created when the base material under the pavement is washed out. Weather is the most significant contributor to the severity of a pothole problem. Excess water beneath the pavement weakens the soil tremendously, particularly when frozen; saturated ground starts to thaw in the spring. A sudden thaw, especially when accompanied by heavy rain, can very quickly wash out roadway base material and create numerous potholes in multiple locations. The creation of potholes can also be related to underground utilities, such as water and sewer lines. A leaking water line will wash away base and soil material, as will a broken and/or open jointed sewer pipes. Regular inspection and maintenance by city street departments and owners of underground utilities will largely limit, if not eliminate, these roadway defects as well as associated vehicular accidents.
In this particular case, the pot hole located next to the manhole was created by a leaking water pipe, owned and maintained by the city, which was repaired during the previous summer. The manhole was owned and maintained by a private utility company and inspected during 12 year inspection cycles. Both the city, as well as the utility company, responded routinely to citizen complaints and repaired reported defects. Not so in this particular case- even after the road defect was reported several times to both the city and the utility company. Both parties opted to settle this case, rather than have a jury decide the outcome.
Conclusion: Roadway design and maintenance can, and do, affect crashes, injuries and fatalities. Practitioners of roadway design, construction, and maintenance can reduce hazards to motorcyclists and other road users by considering user safety:
(Johann Szautner, PE can be reached at 215-659-2010 or via email at experts@forensicDJS.com)
Categories: Case Studies