Shanghai urban planners said yesterday that a project to build new rail lines between two busy stations shared by Metro lines 3 and 4 will start around the end of this year.

The scheme, the first step in a bid to double capacity on Line 4, involves building a pair of 2,020-meter elevated tracks near the current line between the Shanghai Railway Station and Baoshan Road station.

The two stations lie on the northern end of the shared route that covers seven other Metro stops and are the busiest in rush hours.

A total of 1 billion yuan (US$146 million) will be spent on building the new elevated tracks and relocating households, said Zhang Anfeng, an official with the Shanghai Urban Planning and Design Research Institute.

"We decided to start the streamlining project with the neediest section to see how well the design could work to help with future construction on the rest of the shared route," Zhang said.

The new tracks will be built to the north of the current ones near the Baoshan Road station by demolishing buildings while there is a vacant site at Shanghai Railway Station.

"When the work is complete, the new set of Metro tracks will still allow traffic to both Line 3 and 4. But with the extra channel, their transport capacity is expected to double," Zhang said.

A similar expansion is planned to reach the southern end of the shared service at Hongqiao Road Station.

Nearly half the 33.7-kilometer circular Line 4 uses the same stations and tracks as the older Line 3, Zhang said.

However, the rapidly increasing traffic on Line 4 has meant it is impossible to increase rush-hour services.

(Shanghai Daily July 29, 2009)