Highway Defect
EXAMINE WHY A MANHOLE COVER JUMPED OUT OF ITS CASTING
THE "TIDDLY WINK" EFFECT
A vehicle was driving along a main road when it struck an open sewer manhole, lost control and crashed into a tree. The road had been re-surfaced a few months prior. The sewer manhole cover had been raised to match the roadway surface with a casting riser. After the re-surfacing the manhole cover began banging when a vehicle drove over it. A few weeks prior to the crash a neighbor had seen the manhole cover pop out of the casting and roll away. The neighbor found the cover and replaced it . As cars drove over the manhole cover it banged until one night the cover either broke and fell into the manhole, rolled away or someone took it.
Photographs & videos of a tire rolling over an improperly seated manhole cover.
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View video of tire rolling over properly seated manhole cover at 30 mph
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View video of tire rolling over improperly seated manhole cover at 30 mph
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SUMMARY & OPINION
It was my opinion within a reasonable degree of engineering certainty, that the municipality created the condition of the rocking manhole cover by inserting an improper riser ring to raise the manhole cover when the roadway was resurfaced.
Last update: 05/14/2019 Top of Page