When a civilian unit is working he is animated on the map. Most work, with the exception of rail building and prospecting, takes three turns.

On the map, you will know your worker is finished when he returns to the unit cycle for orders. A flashing white outline around the unit on the map tells you he is selected and ready for a new command.

If a worker is deployed (using a green arrow cursor) he does no work during the turn and appears in gray scale and non-animated. Units told to sleep also look like this.