Road failures occur when steeply standing fill becomes saturated and slides. This sort of failure commonly occurs on gentle topography, is easily and quickly fixed, and not generally the focus of serious attention. If on the other hand, the minor road failure occurs on steep topography, then it can accumulate material as it moves down slope and becomes an environmentally significant landslide.

Leading causes of road failures are debris on the primary highway which can be a great problem, and is the responsibility of local highway departments. Signs obscured by plants, and faded motorway signs occasionally contribute to accidents. Potholes cause a small number of accidents primarily tire and suspension failures, but the accidents usually occur at low speeds and don't cause many injuries.

Road conditions including foreign obstacles or substances on the road surface such as rain, ice or snow makes the roads slick and road damage including potholes all contribute to accidents due to road failure.

Lane construction is an oft-mentioned reason for accidents. Again the blame usually rests on aggressive drivers who are unwilling to merge or slow down when approaching a construction zone. In most states, fines are doubled in work zones, making it expensive as well as unsafe to speed. Roadway maintenance contributes to some motor vehicle accidents, but not to the extent that drivers use it as an excuse. Unfortunately maintenance schedules and procedures vary greatly from city to city and state to state, so nationwide standards don't exist. There is not just one type of highway failure, and there is not just one reason for each type of failure, and it is in these situations where it is very difficult to replace an experienced engineer/technician when an accident occurred due to road failure.

Pavement structural failure happens when the pavement has failed, maybe not completely, but in a major way. The pavement is no longer able to absorb and transmit the wheel loading through the fabric of the road without causing fairly rapid further deterioration of the road pavement.

Road failure as a result of structural failure have failed for various reasons, such as through age, inadequate design, or an altering in requirements of the strength of the pavement by increased traffic flow/weight, impeded drainage, etc.. When you have structural failure the solution is always a form of reconstruction.

If you have been involved in an accident due to road failure it is best to consult a lawyer immediately to protect your legal rights and options.