contraflow

noun

1. Flow in the opposite direction to normal.“Example: Contra-flow cycling is a regulatory measure. In streets and roads with a one-way traffic restriction, cyclists are exempt from the one-way restriction and are allowed to drive against the flow of motorized traffic. (European English)”
2. An abnormal state of a road or motorway where the traffic temporarily travels in the opposite direction to normal, usually as a result of repair work or an accident.