One of the key public transport projects on the books – and in our Congestion Free Network – is an extension of the Northern Busway to the north. Thanks to an Official Information Act request by reader Hamish O we now have a whole lot more information about the project. A study on the extension was completed for the NZTA early last year to look at the preferred route for the extension all the way from Constellation Dr to Silverdale. As well as the total route, for practical purposes the report also broke down the sections in Constellation to Albany and Albany to Silverdale. You can read the full report here (8.9 MB) however here is the executive summary.
The New Zealand Transport Agency (the NZTA) has engaged Beca Infrastructure Limited (Beca) to investigate an extension of the existing Northern Busway from Constellation Station to a future Hibiscus Coast Busway Station at the Silverdale Interchange (the NBE). The investigation by Beca involved: review and development of previously investigated and new route options for the NBE, to identify a preferred route; identification of land required to accommodate the preferred route; and consideration of station location and operational issues.
The investigation responds to the strategic objective of the NZTA to deliver an integrated, safe, responsive, affordable and sustainable public transport solution for North Auckland. The extension has been considered as a dedicated facility, separate to SH1 with associated stations being the responsibility of Auckland Transport and Auckland Council. These parties as well as local Iwi have been engaged throughout the project.
Increased population and employment growth is forecast for North Auckland and this will place increasing pressure on the transport network and available land. Current predictions to 2041 show increased SH1 traffic, resulting in congestion and varied travel times for people and goods moving through North Auckland. The need for additional dwellings and places of employment associated with the predicted population growth will require land which may also be necessary for an extension to the Northern Busway.
An extension to the Northern Busway would provide a public transport solution to accommodate some of the transport needs of a growing population within North Auckland. The Busway extension is not predicted to result in a significant decrease in traffic on SH1 because the number of people expected to use the bus rather than travelling by car is small in comparison to the overall number of vehicles using SH1. However, the NBE would improve travel times for people travelling by bus in the future.
To ensure an extension to the Northern Busway can be built in the future there is a need to allocate land for this purpose. This can best be achieved by introducing a new designation for Busway purposes and purchasing required land. It is recommended that the land purchase initially focus on properties where there is likely to be an increase in land value (as a result of population growth placing pressure on available land) and/or where negotiations with land owners may require significant time.
Through investigation and evaluation an eastern aligned option has been identified, and is recommended for the future extension of the Northern Busway. Being aligned to the east of SH1 the option:
- avoids a site of ecological significance at the Lucas Creek West Bush (located just north of the Oteha Valley Road Interchange to the west of SH1) providing for the protection of the environment;
- provides the greatest flexibility for future State Highway improvement projects;
- provides a bus only road link across SH1 to serve the Albany Station, enabling this station to support the future growth of the Albany Centre; and
- is cheaper to construct as it avoids the need to construct one or more major structures across SH1.
Based on economic investigations, the full NBE would likely be economically justified as early as 2019. Should the NBE be constructed in stages, a first stage from Constellation Station to Albany Station could be economically justified as early as 2015. The construction of the Busway during the indicated years would support the growth of the Albany Metropolitan Centre, Silverdale and Orewa in accordance with the emerging strategic direction for growth in Auckland.
The analysis undertaken as part of this project demonstrates that there is little benefit in providing bus shoulder lanes to Silverdale or incrementally. However, the case for bus shoulder lanes should be considered further when the project proceeds to preliminary design, and better information is available as to the associated costs and the effects on the network following completion of other projects (i.e. SH1 to State Highway 18 connection, Constellation to Greville improvements, SH1 to State Highway 17 connection and Penlink).
Prior to confirming the preferred option for a future extension of the Northern Busway and setting aside land for this purpose, it is recommended that NZTA undertake further consultation with Auckland Council, Auckland Transport and Hokai Nuku, in addition to initiating consultation with other Stakeholders, such as Watercare, and the community.
There are two really interesting outcomes to the study that are mentioned in the summary above. The first and most significant is that the preferred alignment is not to the west of the motorway like many people have long assumed but to the east. The second is that extension from Constellation to Albany could be economically by 2015.
So let’s look at the alignment options. The study into alignments needed to take into account the following potential projects.
- Three Laning of SH1 – the proposed NBE design and designation footprint has been developed in a manner that would enable three lanes in each direction to be provided continuously on SH1 as far north as Silverdale without disruption to the Busway in the future.
- SH1 to SH18 Motorway to Motorway Connection – the proposed NBE design and designation footprint has been developed to accommodate a future State Highway 18 (SH18) to SH1 motorway to motorway connection upon completion of the Auckland Western Ring Route (based on current design information).
- SH1 Greville Road Interchange – the proposed NBE design and designation footprint has been developed so as not to preclude improvements proposed at the Greville Road Interchange in the future (based on current design information).
- Penlink (or Weiti Crossing scheme) – the proposed NBE design and designation footprint has been developed so as not to preclude a proposed connection between the Whangaparaoa Peninsula and SH1 (south of Silverdale) in the future (based on current design information).
- Weigh Station – the proposed NBE design and designation footprint has been developed toaccommodate a future weigh station (compliance checking site) located to the east of SH1 and north of Bawden Road, which would enable overweight vehicles to be diverted onto the Western Ring Route away from SH1 and the Auckland Harbour Bridge (AHB) should this be required in the future.
- Hibiscus Coast Busway Station – the proposed NBE design has been developed to accommodate and connect with the Hibiscus Coast Busway Station.
The team investigating this then came up with 5 potential options.
- Option 1: Offline facility primarily on the western side of the existing motorway corridor (crossing north of the Rosedale Oxidation Ponds);
- Option 2: Offline facility wholly on the eastern side of the existing motorway corridor;
- Option 3: Offline facility crossing from east to west beneath SH1 in a covered trench or tunnel and returning to the east by way of a bridge to the north of Lonely Track Road;
- Option 4: Online facility comprising bus shoulder lanes in both directions, accessed via the existing motorway on and off ramps; and
- Option 5: Central median Busway, accessed at Silverdale interchange and Constellation Drive.
After initial screening, options 1, 2 and 3 were considered the best to take forward for more detailed study which assessed them based on integration, social, environmental and economic criteria. I won’t bother going through details so feel free to read the report if you want more info but as mentioned earlier, option 2 was considered the best. Probably the most interesting part of it is how it would access the existing Albany Busway Station. The answer is it would be done by way of a bridge across the motorway which would able to be used by both buses from the south of Albany and those from the North. Essentially it means that only one crossing of the motorway needs to be made.
As for costs it is suggested that the section from Constellation to Albany would cost just over $200 million to construct while the section from Albany to Silverdale would cost just over $300 million although the report does note that the figures have been rounded to the nearest $100 million. A separate report from 2011 also released with the OIA request suggests the costs would be $249 million for the Constellation to Albany section while the Albany to Silverdale section would cost $304 million.
To put things in perspective the original busway cost around $220 to build the roughly 6.5km of busway from Constellation to Akoranga. The study – as well as a separate one done at the same time by Auckland Transport – also considered whether any new stations could be justified along the route. The only one that was considered to be potentially viable was one at Greville Rd
One other comment really caught my attention in the report. It is this from page 18 and 19 and it explains quite nicely just how successful the existing busway and associated improvements have been.
Over the past few years investment in the Northern Busway, and efforts to improve bus and transit lanes in other parts of the North Shore, have resulted in a significant increase in the proportion of trips made by bus. Not only has the number of bus users across the Harbour Bridge improved significantly during this time, but there has been a decline in the number of cars crossing the bridge: freeing up space so everyone’s trip is faster and more reliable.
Recent figures indicate that almost 12,000 out of the 29,000 people crossing the bridge in the morning peak period are now travelling by bus (i.e. almost 41 percent of all people use the bus). This figure represents a significant increase in bus mode split compared to 2004 (which had roughly 5,000 out of 27,000 (18.5 percent)) of people crossing the bridge at peak times by bus.
Personally I think that the extension from Constellation to Albany needs to be built as soon as possible and is far more important than the works the government is proposing in the area with the motorway upgrades (which to be fair do mention Northern Busway improvements).
Lastly thanks to Hamish O for putting through the OIA request for this.