Well it seems as though yesterday’s announcement that NZTA had lodged the notices of requirement for the future cross-harbour tunnels was no co-incidence, as today the previously mentioned ANZAC Bridge idea is going to be unveiled. As shown below, the ANZAC Bridge is not only a new bridge, it’s also a replacement for the existing bridge rather than in addition to it.
Buses, trains, pedestrians and cars would all use this new bridge, we would demolish the existing harbour bridge and (theoretically at least) use money gained from redeveloping the land used by the motorway through St Mary’s Bay to help pay for the crossing. So let’s look at what I think the advantages and disadvantages of the bridge option are:
1) It’s cheaper – around $2 billion compared to around $4 billion for the tunnels idea. Operating costs of a bridge are also less than a tunnel.
2) Suspension bridges look really cool.
3) The city could “take back” the St Mary’s bay foreshore.
4) It would be a shorter route for vehicles (from Tank Farm across to Northcote Point) than the current route.
1) It would have a pretty enormous impact on the part of the CBD where it “landed” at its southern end. This could potentially ruin Westhaven Marina, Tank Farm and/or Victoria Park.
2) By it being a replacement for the existing bridge, the end result would be that you still only have one crossing of the harbour. One of the main benefits of another harbour crossing is that you have just that – another crossing. This adds redundancy in the case of something going terribly wrong with the bridge.
3) It’s going to be damn difficult getting a railway line from Britomart (8 metres below sea level) up to the bridge (say 20m above sea level) without being incredibly disruptive and ugly.
4) Ngati Whatua (Auckland’s most prominent iwi) might well have some to say about the reclaimed land around St Mary’s Bay simply being sold off. Under the Public Works Act if NZTA are no longer using it for motorways then they would have to “offer it back” to its original owner. Depending on the outcome of Foreshore and Seabed legislation changes, this could well be Ngati Whatua.
5) The tunnel option splits traffic travelling to the city (which would use the existing bridge) from traffic travelling through the city (which would use the tunnels). I reckon this is a good thing, and having only one crossing would remove this gain.
Overall, I think the tunnel option makes more sense. Although I question how absolutely necessary it is any time soon.