"Linking new lines with existing lines and awarding the operations to existing operators is the best option for all parties. There is no need for the purchase of new train carriages, and this alone will save 20 per cent of the project cost," said Surasak Taweesilp, managing director of Team Logistics and Transport.
Surasak said if old and new lines were not connected, the government would need to find a new operator for the new route. New train carriages will be necessary, which will cause commuters to pay more for cross-line travelling.
The 11.4-kilometre Green Line's construction value is estimated at Bt30.77 billion. It will run from Morchit to Saphan Mai. At present, the Skytrain network stops at Morchit.
The consultant said connecting the old and new routes would maximise benefits for all parties. While the government will save investment money, the extended networks will draw more commuters. As existing operators gain more revenue, they will not need to raise fares. While the operating cost is saved, energy consumption will also be cut.
At present, the Skytrain costs Bt15 to Bt40 per trip, while subway fares are Bt14 to Bt38. The consulting company's study said if the lines were extended, their operating cost would be only Bt1.5 per kilometre.
"As a consultant, we proposed two options. The new route could be linked to the existing networks or run separately," Surasak said.
He said the connection would not benefit any particular supplier, as the Skytrain's signalling system could be adjusted for any train carriage.
Pranote Suriya, deputy director-general of the Transport and Traffic Policy and Planning Office, said a committee consisting mainly of representatives from the Finance and Interior ministries had been formed for negotiation with Bangkok Mass Transit System, operator of the Skytrain.
"We should reach an agreement that is win-win for all," he said.