The upgrades were made in such a way that a future tram-train can run on the route.
The line, which runs four morning trains on the 35-mile route to downtown, increased the number of cars per train to eight from three.
"I'm thinking they're going to run the tight end on the inside route," he said.
Three public buses run on the route including No. 52, 67 and 78.
In the last decade, several private companies have run ferries on the route.
Passenger trains will run on the current route through Freiburg.
The Southern Line suburban services continued to run on the old route.
The local buses would run on the same route, however they would stop at each and every station.
Apart from State transport, a number of private operators run their bus services on the same route.
As of 1932, only two trains ran on the route - one in the morning and the other in the evening.