O'Donnell v. City of Casper
In O'Donnell v. City of Casper, 696 P.2d 1278 (Wyo. 1985), the Court discussed the viability of the exception in light of the adoption of comparative negligence.
Mr. O'Donnell operated a motorcycle and encountered an accumulation of gravel remaining on the street from a resurfacing project performed by the City of Casper.
The Court distinguished the facts in O'Donnell, an instance of injuries arising from a man-made cause, where the city placed gravel on the street and allowed it to accumulate in ridges and piles, from instances in which liability arises from natural causes.