Comments on: Onehunga Line Information

By: Saljen

Saljen — Tue, 08 Sep 2009 03:05:12 +0000

Hi Bob,

For your fears about the triangular junction at Onehunga there, I would guess there would have to be two platforms, rather than just the one. If the Avondale-Onehunga part comes along the motorway (as it seems they want now), then might have to go along/under Neilson street and join this planned Onehunga station at the bottom left of the plan above to create a through station.

Then the Airport part could have a platform on the right of the tracks starting from under Neilson street and continuing up very close to the planned Avondale-Onehunga platform. Then stairs up and over the tracks can connect the two platforms up near where the “Landscaping area” is over to the other platform on the other side of the Mangere bridge tracks. i think that might be a good solution.

Because it is a sharp triangle and not a 90 degree one like Newmarket , the platforms can be reasonably close to each other, unlike say Kingdon street and Newmarket.

By: bob

bob — Mon, 07 Sep 2009 15:00:39 +0000

Oh, and the ARTA proposed station has platform length constrained by the (high traffic) road junction at the end of the platform. It appears to be 2 carriage length, which limits passengers you can take if peak traffic growth turns out to be big (which is quite possible, given Mangere-CBD bus passengers could swap from bus to train at Onehunga quickly, and speed their journey.

That short platform length would also force Veolia to use ADL or ADK 2-car trainsets, which adds to timetabling constraints. That is, Veolia won’t be able to use a spare SA trainset that’s just finished a West line run to go Britomart-Onehunga, because it can’t fit on the only 2 car length platform in the regional network… Whereas any platform on Princes St (or on the SAL or Airport line theoretically) can be expanded.

By: bob

bob — Mon, 07 Sep 2009 14:46:45 +0000

Eeep! Thanks for posting this diagram – it is a shocker! Bizarrely, the planners have managed the worst of all worlds

The Onehunga rail station site is a triangular junction, as Jezza hinted, with lines from:
* East is the existing Penrose-Onehunga 1 track line being rebuilt
* West is planned Southdown-Avondale line (SAL), which would roughly be Onehunga-Avondale from this junction.
* South is proposed Onehunga-Airport line, which ARTA are consulting/planning on a designated route for currently.

So you have the Newmarket station problem all over again – there is no way you can fit platforms for more than 1 carriage length inside the triangular track junction, so any station must be on one of the 3 lines above, as close to the junction as possible.

So, which line to put the platforms on? Look at patronage estimates. From memory, Auckland Airports 2004 (or thereabouts) study into PT access to the airport showed Airport patronage coming 1/2 from Auckland City Council area, 1/4 from North Shore, and 1/4 from Manukau East (Howick, etc), with very little at all from Waitakere City or South-West Manukau.

So, given the Onehunga-Penrose-Newmarket line serves both ACC and most directly links to North Shore (via NS Busway and ferries at Britomart), the case is overwhelming for the platforms to be on the Onehunga-Penrose line. That is, along Princes St in Onehunga, between Galway St and Spring St. It’s tight, but there is space for a single side platform there (its a wide but quiet road that can be crimped), especially if the adjacent firms sell their driveway next to the track.

But the shown ARTA diagram would cut right through any junction of the future SAL and Airport rail routes with the Onehunga line, meaning the proposed station has to be bulldozed and rebuilt… aargh!

Sorry for the long comment – I looked at this a few years back, and ARTA were all at sea back then ;( There seems to be an obsession with the old station site, which is not the best platform location. They want to get close to the shops, but the biggest shops are the DressSmart mall, just North of Princes St. Besides, platforms are long beasts, and generally have an exit at either end, so the Galway St exit of a Princes St platform is just as close as the ARTA platform to the mainstreet Onehunga shops.

All this assumes a SAL and Airport line eventually get built, but as Jarbury said in other posts, if you don’t plan, you don’t get (paraphrased)… Certainly, building a modest Onehunga platform along Princes St allows seamless expansion of Onehunga line to Avondale and/or Airport without cost & hasle of rebuilding platforms. And Princes St is straight, which the train drivers appreciate

By: admin

admin — Fri, 04 Sep 2009 07:12:05 +0000

Indeed they might not want to give it up. I talked to someone from the RES last night and he said it would be up to the membership to decide.

In terms of a carpark, I think that until the site is fully redeveloped it is likely there will be parking on the site. Which is OK.

By: Lewis

Lewis — Thu, 03 Sep 2009 21:09:28 +0000

P.S. the old railway station is owned outright by the Rail Enthusiast Society – I suspect they might not want to give it up.

By: Lewis

Lewis — Thu, 03 Sep 2009 21:06:47 +0000

Pacifica Shipping were interested in starting a shuttle service to the downtown wharves from Onehunga a couple of years ago, but nothing came of it. The proposed station won’t affect that – the real problem is the trackbed to the Onehunga wharf has been sealed over for the new SH20 bridge across the Manukau harbour.

Does this design include space for a carpark?

By: Jezza

Jezza — Thu, 03 Sep 2009 12:07:36 +0000

I wonder what will happen to the station and the station alignment if the SAL goes along SH20 the whole way..?

By: admin

admin — Thu, 03 Sep 2009 11:42:57 +0000

I am pretty sure that the line will be available and usable for freight – that’s if Port of Auckland want to use it. Ontrack’s upgrades only went as far as where the station will be I think, so the track is still sub-standard beyond there.

By: Libertyscott

Libertyscott — Thu, 03 Sep 2009 11:35:13 +0000

I’d be interested to see if the option to retain it for freight to the wharf (and elsewhere on the line) can be maintained. It would be a pity if that went, partly because it has lasted most of the last 40 years because of freight.