You can still get through, I went about two weeks ago. The Lismore road end (under the old station, now a restarant) has a big security fence with a gate, which was open when I was there. The Balcarres Ave end is fairly well hidden behind a new street of houses and some bushes. It is pretty well fenced off. It goes right to the roof so it's difficult to get through. If you look at the left hand wall there's a small gap between the fence and the wall. If you're of a slim build you can *just* squeeze through. When we went though we met people half way, it was pretty scary! We put our torches off and waited to see what they'd do. Eventually we sneaked back out the Balcarres end and ran round to Lismore road to see if they'd come out there, but there was no sign so we went through in the opposite direction. It's a good tunnel, long and dry.