A backhoe operator ran into underground cables Thursday and turned much of the downtown into a parking lot.
The location is where a crew has been at work for several weeks: Avenida 7 at Calle 5.
The job is for the Instituto Costarricense de Acueductos y Alcantarillados, the water company.
Traffic police closed off Avenida 7, a principal eastbound route, and they did not specify alternatives. Vehicles were backed up to the east as far as Calle 23 and the Antigua Aduana. Bus service was frozen.
Thousands of vehicles were tied up for as much a 90 to 120 minutes.
Traffic police were seen watching the jam, but they did not take any action.