Ian Woodcock (RMIT) and John Stone (Melbourne Uni) have a new report out comparing level crossing removal methods. The Age has a story on it this morning, and hopefully the full report will be online very soon. UPDATE: Here it is.
I did manage to get a sneak preview, and looks at various case studies around Melbourne, and tries to evaluate aspects such as: connectivity, accessibility, intermodal access (eg interchange), safety, economic development and amenity. The summary table is here:
Method depends on motivation
One of the really interesting points it makes is that the motivations for using various methods have been quite different over the years.
Prior to World War II, it was mostly about improving rail efficiency, and whichever method resulted in the slightest gradient was what got used. So if one looks at the Glen Waverley line, extended from East Malvern and opened in 1930 (and the last big suburban rail project until Regional Rail Link opened in 2015), there are no level crossings, and it’s a mix of rail over and rail under.
After World War II the emphasis was about moving cars, and the cheapest method was road over, such as at Burnley, Oakleigh and Sunshine. The result, the report authors point out, disconnects communities and makes life very difficult for pedestrians and cyclists at street level.
More recently the trend has been trenched rail under road. The high cost of decking mostly prevents additional connections across the tracks or use of land above it. I suspect some people like that it’s out-of-sight, out-of-mind (well, except to train passengers and pedestrians), but the report points out problems with this method — particularly in terms of lack of integration between stations and local neighbourhoods.
As I understand it, putting stations at the bottom of a trench also has poor consequences for rail efficiency. One of the numbers I’ve heard is that it can add 6% to train energy consumption. From this perspective ideally you want stations on a hump, so they can easily brake into stations, and use minimum energy accelerating out of them again.
The report authors have plotted the history of Melbourne grade separations in this fascinating graphic, and you can see the trends over time:
As I’ve said many times, all methods have pros and cons.
One lesson here is that one shouldn’t judge current proposals based on what’s been done before. Melbourne has no good past examples of grade separation that was designed to maximise connectivity, economic development and amenity. Most of the past projects have only been targeted at improving rail or road operations, and that’s all they’ve achieved.
Elevated rail such as proposed for the Dandenong line has obvious impacts on those living closest to it, but if designed well it also brings a lot of benefits in terms of overcoming engineering challenges, construction impacts and eventual outcomes such as land use.
The report is well worth reading: Level crossing removals: learning from Melbourne’s experience