I think this is quite clever.
When trains or trams are partially closed for planned works, generally the less of the route is disrupted, the better.
But this is always limited by the placement of turnaround facilities. Witness the current Sandringham line closure: the major works are at South Yarra, but because (despite what was said beforehand) the infrastructure issue at Elsternwick hasn’t been fixed, the whole line is closed.
Over on the trams, they have an ingenious solution: a portable, temporary crossover. It was in use in Swan Street in Richmond (route 70) for a few days this week while tram platform stops are built:
This enabled them to terminate trams at Richmond station, with disrupted passengers able to either change to a train, or walk 400 metres to where trams could resume.
Apart from placement of the temporary track, they also needed to install some overhead wire. Of course it’s made easier to manage in this case by the road closure.
But it’s smart thinking, allowing trams to run as far as possible, reducing disruption for passengers, and avoiding the mess and cost of replacement buses.
For long term projects, it still sometimes happens. Over Easter, the Dandenong and Frankston lines near South Yarra were ripped up and rebuilt as part of Metro tunnel works, and will be ripped up again as the junction to the new tunnel portal is built. There have also been tram tracks relocated on St Kilda Road which may need to be relocated again as the tunnel works continue.
But overall, temporary track is less common in modern times, at least on short term projects.
If only it were this easy on the railways.