The long-awaited South Island Line project ranks fourth in urgency on the government's railway development agenda because a study foresees no major traffic growth in the coming 15 years, a senior official said yesterday. The MTR extension, to connect Admiralty and Ap Lei Chau, had been ranked behind the West Island Line, Hong Kong-Guangzhou-Shenzhen express link and the Sha Tin-Central express rail link, principal assistant secretary for environment, transport and works Henry Chan Chi-yan said. But agitated councillor Chai Man-hon jumped on the table in protest, saying the priority issue was rubbish because there was no timetable for the first three lines. Mr Chan said a study by Housing, Planning and Works had found no link between the expected growth in Ocean Park's visitor numbers after its redevelopment and any pressure on the district's transport network. The extra people in the area as a result of the expansion of Ocean Park and other commercial developments would not justify the immediate building of the line. In a document submitted to the Southern District Council, the Transport Department said only slight traffic jams were expected in the area by 2016 without the MTR extension, increasing by 2022 into what officials term a 'mild' traffic jam. As to the extension's impact on other public transport, the department is still commissioning a report, but operators of franchised buses and minibuses have been expressing concern. The bureau said that since the MTR's Tseung Kwan O line, West Rail and Ma On Shan extensions came into service, many bus routes had been chopped or streamlined.