Train services in Sydney's northern suburbs would be disrupted for almost a year before the opening of the north-west rail link, under proposals recently approved by the state government.
In late 2018 and early 2019, the government plans to shut the existing Epping to Chatswood line for seven months to make the line compatible with the sort of trains it will run on the adjoining north west rail link.
But before then, the government is planning to run shuttle trains between Epping and Chatswood for four months, meaning commuters from the city or Hornsby will have to change trains to access stations such as Macquarie Park or Macquarie University.
Transport for NSW says "survey work and inspections" in the existing Epping to Chatswood tunnels have already started as part of a project to convert the train line to what it calls "rapid transit" - single deck trains that will operate without drivers. The department recently granted itself planning approval to undertake this conversion.
Optus, which has a large office facility at Macquarie Park, was one business to raise concerns about the reliability of replacement bus services during the period that train services will be suspended. Transport for NSW says it will run five bus routes, and more than 300 services, every weekday to replace the train line.
But the department estimates public transport users travelling to stations on the Epping to Chatswood line should allow an extra 10 minutes to 45 minutes for their journeys when the line is closed.
Optus, however, questioned whether traffic congestion would be worse and trip times longer by 2018, which is when the replacement buses are to start.
Transport for NSW says it needs to close the Epping to Chatswood line, which opened only in 2009, to modify overhead wiring, change power supply, signalling, communications and fire systems, and undertake a number of building works to make it compatible with the new rail link.
The contract signed with the operator of the North West Rail Link, a consortium including Hong Kong's MTR and UGL, specifies that 30 per cent of the capacity of the trains needs to be for seated passengers. When Sydney's existing trains are full, about 75 per cent of passengers are seated.
