Electrifying from Papakura to Pukekohe

Well it looks like Auckland Transport has already started responding to the calls by new chairman Lester Levy to be more transparent. The AT board meets next week and one interesting paper going to them in the open session is the business case for extending electrification from Papakura to Pukekohe. The paper going to the board recommends that the project be including in ATs capital plan but says that more work is needed to work out how the project could be funded which would either need to be by an additional funding source or re prioritising existing projects.

Work completed as part of the City Centre Future Access Study, including looking at where future greenfield development might occur, has helped feed into the business case. They have assessed that the population between Drury and Pukekohe will more than treble over the next 30 years going from around 23,500 to 78,300 by 2041. Four options were looked at and assessed:

The business case also suggests that the options of increasing the frequencies south of Papakura or even running express diesel trains all the way to Britomart were looked at but ruled out due to the operational complexities and that there isn’t enough patronage to justify them. All three of the electrification options contained the following requirements with the only differences being the cost of station construction.

The electrification options (A-C) include signalling, overhead line equipment (OLE) and trackimprovements required for electrification. KiwiRail advise that there is no requirement for additional traction power in any option.

There are nine road-over-rail bridges between Papakura and Pukekohe. Detailed measurement has identified that three bridges along the route would need to be replaced because they lack the minimum clearances required for electrification (see appendix). The bridges are Onslow Road, the Southern Motorway (Northbound) and Stadium Drive No.2. Track lowering is required under one additional bridge at Great South Road, south of Drury. Track lowering was discounted as an uneconomic solution for the other three bridges due to the need for expensive works to underpin the existing bridge abutments.

AT estimate that only two extra 3-car EMUs are required under the electrification options. Spare EMUs are not required given the synergies of operating as part of the wider EMU fleet.

Its interesting to note that only an additional two EMUs are required to enable services to be extended vs needing four to run services using a diesel fleet due to the need for spares. When looking at the benefits however AT suggest that 90% of the benefits for the proposal comes from increased patronage with most of the rest coming from operational savings due to things like having a common fleet. The costs and benefits for each option were assessed using the standard NZTA criteria and the outcomes are below with the recommended option being C.

All up it looks like quite a bit of effort has gone into this business case and it definitely seems like a project we should be doing we should be doing. I would also go further and suggest that based on the maps we saw recently (linked to above) there might even be a case for a station between Drury and Paerata which may bump up the business case even more. The business case suggests that we should be aiming to have the wires up to Pukekohe by 2016 when the last of the EMUs arrive so if funding can be found it could be something that starts to happen fairly soon.

Finally its really great to not only see this report but also to see the level of detail being released, well done AT.