ABOUT 1300 workers will carry out maintenance and enhancement works along the Hunter Valley rail network this week.
It's all part of a scheduled three-day program involving 125 projects to help deliver a safe and reliable rail network.
The work will be undertaken from the port at Kooragang and along the rail corridor to Werris Creek, as well as the Ulan line west from Muswellbrook.
Australian Rail Track Corporation (ARTC) group executive for the Hunter Valley Jonathan Vandervoort said the maintenance works would include re-signalling at Thornton, a level crossing upgrade at Army Road at Glenridding and track reconditioning at Quirindi.
"The Ardglen Tunnel will also be re-sleepered and re-railed," he added.
"This is an interesting job as it is a heritage-listed tunnel and we have to take those considerations into account while undertaking the works.
"We will also take advantage of the opportunity to undertake a number of works including removing ballast and improving drainage on this section.
"With tunnels you need to be very efficient as the conditions are difficult to work in and to you need to be very organised to get all the works done in the allotted time."
Mr Vandervoort said to ensure the rail network continued to operate efficiently and safely, a shutdown on the network was in place.
"Similar to other recent maintenance programs, a scheduled shutdown is required to allow us to access the track for maintenance and upgrades that cannot be done safely when trains are running," he explained.
"The work will generally start at 6.30am on Tuesday, November 19, and is expected to be completed about 6.30am on Friday, November 22.
"However, some small sections will start earlier including Pages River to Chilcotts and Chilcotts to Werris Creek.
"We apologise for the inconvenience and, as always, we appreciate the patience and cooperation of motorists, commuters and customers right across the maintenance program.
"We also ask people in communities close to the rail corridor to be cautious during the shutdown period and keep an eye out for increased vehicle movements in and out of work sites."
With the shutdown affecting Hunter Valley train services, alternative bus services will be provided, and details and schedules can be found at the Transport for NSW website.