Why can’t South Auckland be green
When I have debates about the Southern Airport Line (Botany to Airport Rapid Transit via Manukau and Puhinui) with others the debate is usually around economics (cost and capacity) and basic environmental stuff (capacity and cars off the road). What I forget (and naughty me in being a Geographer as well) was the deeper environmental impacts between a bus way and a light rail line – that is surface run off of storm water and the possibility of carbon sinks.
A busway is basically asphalt from beginning to end – so hard run off. Yes in New Zealand we do storm water gardens for hard surface run off before that said storm water hits the waterways but is that an appropriate response for an existing urban area like Southern Auckland?
Light Rail goes further in that the right of way is already green with the only hard surface being the tracks themselves (the sleeps would be under the soil surface). This means each time it rains the storm water is already collected by the green right-of-way, filter and finally peculated before hitting the waterway systems. No need for storm water ponds and flooding also becomes mitigated as well unlike what we would get with bus rapid transit (BRT). Also green is just nicer to look at than grey asphalt especially in an urban area.
These tweets from Transit Sleuth illustrate green transit:
So my question is this?
If the Isthmus (Central Auckland) is to get Light Rail for the Northern Airport Line and no doubt a green LRT line at that (Dominion Road) then why does Southern Auckland get stuck with a noisy bus rapid transit system that has consequences of amplified noise (bus, and asphalt reflecting the noise) and mass storm water run off from the asphalt?
As it was pointed out to me Southern Auckland also houses four of the five heavy industrial complexes meaning hard surface area is higher – thus run off is higher. The Southern Airport Line runs through two of the complexes so adding some green would mitigate that run off. A green transit line for the SAirL would also act as a carbon sink for the industrial South as well rather than as a carbon emitter as we would otherwise get if the line was BRT.
Also is Southern Auckland not allowed a green transit line like the Isthmus is – especially as the Southern Airport Line if your first transit line you catch heading to either the City Centre or south of Auckland?
I personally think that it is a bit stink the Isthmus gets a green transit line than the more populous South. Just because we have industry and social deprivation does not mean we can not have a green transit line either.
Noise reduction, storm water absorbent, carbon sink, amenity provider – this is what a green transit line would provide compared to the sea of asphalt a bus way would give in an otherwise highly built up area.
As for cost? Yes Light Rail costs more than Busways in pure dollar terms but in full social and environmental terms green LRT wins out. Especially when the Line traverses industrial areas or highly built up areas like a large Metropolitan Centre such as Manukau.