The freight (and passenger) lines have a fixed point of elevation as they cross the Goodwood Road subway, so lowering north of there is a pointless exercise.rhino wrote:Are you sure about that? (the part in blue). If it's true, then you would be starting the decline just after the Seaford line goes under the freight line, which means it would probably be more efficient to put the freight line under the Seaford line. I suspect the freight line would require more than a kilometre to get it back to grade. It would be fine for commuter trains.wilkiebarkid wrote:Leave Cross Road as it is and have a long gradual underpass for the rail line. Having it lowering and rising, say, one kilometre either side of Cross road, it would not be too much of an impost on the freight trains. It would need to go under Hilda Terrace too. That's 2 less railway crossings.
The assault on the grade "up the hills" begins at Goodwood road, so any lowering to go under Cross Road only makes the existing grade steeper. Look at the elevation of the rail line at Hilda Tce crossing compared to the Cross Road crossing (just 300m apart). Lowering the line an extra 10m at Cross road would need a lot lot more than a kilometre for the grade!
One thing I can see is not seen by many here is that the proposed grade seperation of Freight and passenger lines at Goodwood will aliviate delays at Cross Roads and other crossings further south.
The current arrangement means most freight trains have to slow and stop before getting clearance across the passenger lines at Goodwood, for those traveling down the hill it means a gradual slowing down from further back than Mitcham.
Thus they cross the Cross road level crossing at very slow speed and can sometimes foul the crossing when the train stops for the Goodwood cross over, hence the long delays for the motorists.
With the grade seperation freight trains will no longer need to slow and stop for clearance, and hence pass through the whole area a lot quicker, and thus reducing the delays at Cross Road.