Drawbridges

Netherlands Railways has never been known for throwing money to obtain equipment if that wasn’t strictly necessary. And a massive three track drawbridge that I have the temerity to try and build across a somewhat minor waterway would precisely be what any Dutch railwayman would get the hiccups from trying to suppress scathing laughter. If opening bridges were already required in those circumstances they’d very likely would put in a lifting bridge hoisted by four rather unobtrusive pillars. Many are the examples around the country, and a three-track bridge would in that case not really a problem. Yet I’d like a bascule bridge. I found these pictures of a smaller-double track example, The Spoorbrug Alkmaar that spans the ancient North Holland canal, seems about the right one to go for. It would not unduly tax my (lately badly under-used) skills as a modeller and I could actually decide to put in that Panama-wheel drive as shown on the one in Medemblik in my previous mail on the subject, instead of the cogged diagonals driven by a cog-wheel inside the uprights of the bridge as shown here. There are examples of that on bridges that were taken out.

Pic number 1 shows the bridge being used by a Plan V EMU, a type of electric train introduced in fairly large numbers as two-car units between the 60’s and the 80’s (in fact, the oldest ones appeared in the then de-rigueur green livery and were painted yellow later in their lives). They are all out of use now.

Pic 2 gives us a view across the bridge-deck showing various details.

Pic 3 shows a VIRM double deck unit from Nijmegen and Arnhem via Utrecht to Amsterdam, Alkmaar and Den Helder crossing. This is a bit of history for me: A friend who was a Dutch tutor-driver and who passed away earlier this year shortly after retirement took me on a nine-hour job in 2005, on just this service along this route and I passed that bridge. It was the last time ever that I drove a train.
As you can see the bridge has no catenary: like we did on the Southern here in the UK the driver shuts off and his train takes this gap un-powered. Like on the Southern, there is a risk that the train gets stopped with its pantograph (third rail shoes) in the gap: it happened and in that case the train is gapped, as the term is on the Southern. Another issue is that Dutch electric rolling stock had limiters on the reach of the pan: a driver did not have to lower the pantograph but rolled through the gap with the pan up and would therewith find his line-light light up when his pan got juiced-up again and he could open up. The appearance of foreign rolling stock without those limiters on the Dutch network soon showed the use of fitting electrified catenary on the bridge: a French TGV high speed train lost its pantographs on the original Amsterdam to Leiden airport line on such a drawbridge. Which brings us to the why of nu such equipment having been fitted here? The answer is that the height of the portal across the tracks is insufficient as well as the tail of the balance being too long in case of this bridge. I know that the line from Alkmaar to Amsterdam was electrified in 1931 but that the section from Alkmaar to Den Helder, in which this bridge is located, was only electrified in 1958. Which is when this bridge was built to replace the old revolving bridge. Given that this bridge is very close to Alkmaar station it does make you wonder why no measures were taken to ensure that trains never got stuck. In this case one thing that obstructs an upgrade of electrification across the bridge is the tail end of the balance with the counterweight, which would touch the wires and push them to the ground. So in my case I’d make the portal of the bridge higher and possibly redesign the balance to fall beside or in-between the tracks. There is a video on the internet that shows an electric train crossing this bridge with its pan raised, incidentally (type in Spoorbrug Alkmaar).  Notice furthermore the red lights for the pedestrians/ bicyclists crossing, the closed barriers as the bridge is about to be opened, the Automatic Half Barrier just beyond the bridge and the obligatory stop boards for trains that popped up from somewhere below. One hopes that the covering signals are showing red aspects and that Automatic Train Protection catches out those drivers who missed them. No joke, read US railway history about a few high-casualty accidents with trains on lifting bridges.