Project introduction

The Christchurch Southern Motorway Stage 1, a four-lane median-separated motorway between Collins Street and Halswell Junction Road, opened to traffic in mid December 2012 and now provides a safer, more efficient and reliable route between the central city, Lyttelton Port and southwest Christchurch.

Project overview

The Christchurch Southern Motorway Stage 1 (CSM1) was delivered ahead of schedule and on budget.

Fulton Hogan was awarded the contract for constructing the CSM1 in January 2010 and work started in March. The total cost of the project is $140 million, making this the largest road construction project in the South Island in recent times.

The CSM1 is part of the Christchurch Southern Corridor. The second part of this project – Christchurch Southern Corridor Stage 2 (CSM2), runs from the Springs Road/Halswell Junction Road intersection, rejoin SH1 by Robinsons Road and then runs along SH1 from Robinsons Road to south of the Weedons Road/SH1 intersection.

The benefits include:

  • Faster trips – shorter travelling times. The extra lanes reduce peak-hour traffic congestion, making travelling times shorter and more reliable.
  • Improved access. Freight can more easily get in and out of Lyttelton Port and traffic flow in and out of the Christchurch Central has also been improved.
  • Safer streets. By moving heavy traffic off suburban roads, they will be safer and more pleasant for walking, cycling and public transport.
  • Economic growth. $140 million dollars has been invested in the Christchurch economy over the last three/four years, generating jobs directly and indirectly.


This project connects the Brougham Street Expressway (SH73) in the east with Main South Road (SH1) in the west. The 10.5km-long project has three distinct sections: upgradenew road and duplication. Construction work started in early 2010 and was completed in December 2012 on budget and ahead of schedule.

  • December 2012

    CSM1 opens to traffic

    Minister of Transport Gerry Brownlee formally opened the 10.5 kilometre Christchurch Southern Motorway Stage 1 on Friday 14 December at a celebration marked by a blessing, ribbon cutting and tree planting ceremony.

    The Christchurch Southern Motorway Stage 1 is the largest road construction project ever seen in Christchurch. The new motorway will carry 41,000 vehicles each day from the Brougham Street Expressways to Curletts Road and 21,000 between Curletts Road and State Highway 1. The motorway was complete on budget and ahead of schedule.

    One of the southbound lanes of the new motorway was opened to traffic on 1 December 2012 and a city-bound lane was opened on 10 December 2012.

    Parts of the motorway will remain one lane and under a 50km/h speed restriction while some work continues adjacent to the motorway. We hope to have the majority of the speed restrictions lifted and all lanes operational by Christmas.

    The new motorway will reduce travel time between Barrington Street and Main South Road (SH1) by about 10 minutes and this is just one of the benefits of the new motorway in improving our road network around Christchurch. Traffic congestion in the area has eased leading to less heavy vehicles on suburban streets.

    In Spring next year, once the new motorway surface has had a chance to ‘bed in’, we will resurface the chip-sealed section between Curletts Road and Halswell Junction Road in asphaltic concrete, a similar material to that used on the section between Barrington Street and Curletts Road.

  • November 2012

    On Saturday 17 November the public were invited to walk or cycle on the new motorway before it opened to traffic. The day was well attended and many local people enjoyed the chance to check out the new section of motorway between Curletts Road and Halswell Junction Road. The Christchurch City Council took this opportunity to open the 8.5km share cycle and pedestrian path that runs from Barrington Street to Halswell Junction Road.

  • August 2012

    Barrington Bridge opening

    The Barrington Bridge was opened to traffic by the Hon Gerry Brownlee on 25 August 2012.

    The new Barrington St Bridge is significant because it is the first of the mainline 'motorway' bridges to be opened to traffic. It is also the first milestone in the new construction season that will see, over the next 4 months, various stages of the new motorway opened to road users. We are opening the interchange at the Barrington Street over bridge early so road users can enjoy some of the motorway’s benefits sooner.

    Work started on the Barrington St Interchange with clearing and stone column trials in February 2010. There was also extensive noise and vibration monitoring undertaken in these methodology trials to minimise the impact on surrounding property.

    We installed approximately 450 stone columns under the Barrington St bridge abutments to lessen the risk of potential liquifaction in the event of an earthquake. These ranged in depth from 8 to 12m and in total length add up to about 5 kilometres of columns.

    The works in this area have included significant safety improvements to the Collins / Simeon / Brougham St intersection and will help reduce crashes at the existing Jerrold St / Barrington St intersections. The overall form of the bridge along with landscaping and urban design elements of the work are designed to be sympathetic to the urban environment surrounding it.

    This project will relieve current traffic congestion points on the state highway network. It also represents a significant environmental improvement for the surrounding community as traffic is moved to the new carriageway and away from parks, housing and walking / cycling facilities.

    When completed, Stage 1 of the Christchurch Southern Motorway will provide a safer, more efficient and reliable route between the Central City, Lyttelton Port and southwest Christchurch.

  • April 2012

    Recent good weather has helped with the pavement and sealing.

    The Springs Rd and Halswell Junction Rd roundabouts are now finished along with the 4-laning between them. The upgrade of the rest of Halswell Junction Road to Main South Road is close to completion.

    The green fields section of this project, from the Curletts Road interchange to Halswell Junction Rd, is well underway. Work on the eastbound (city-bound) lanes will continue as long as weather permits over winter.

    Work on the Curletts interchange is making steady progress, with piling on the east side of the Curletts Rd Bridge nearly finished and pavement work scheduled to continue over winter.

    The remaining section of the project that duplicates the two lane motorway section between Curletts Rd and Barrington St is on target to be finished as planned in February 2013.

  • June 2011

    Earthworks are taking place in Zone C to provide a working platform and access road suitable for construction traffic throughout winter. A layer of shingle will be placed alongside the existing embankment. This allows construction to occur during wet winter months. The existing topsoil, where the embankment will be built, will progressively be stripped and replaced by bulk fill that will be brought in with road truck and trailers.

    Activities also include ground-strengthening works for the structures, including piling and settlement surcharging. Surcharging is the overfilling of embankments, particularly near structures, to accelerate the ground settlement caused by the weight of the new embankment. Excess material is removed to the finished height in line with the design of the structures. This means for a while in some areas embankments will be built higher than the final finished height.


Construction zones

  • Zone A: upgrade

    Halswell Junction Road - from Main South Road (SH1) to Springs Road. This section of the project is complete with new traffic signals at the Shands Road intersection and an upgrade to the Springs Road roundabout. Works began in September 2010 with a focus on ensuring minimal disruptions to traffic flow two traffic lanes were retained at all times with periodic work at night.

    • Relocate services

    • Traffic signals at Shands Road

    • Reconstruct and widen road.

    Sequence of work started in September 2010
    • Construction works generally west to east

    • Advise businesses of programme

    • Relocate services

    • Drainage upgrades

    • Pavement reconstruction – eastbound lane first

    • Early completion of footpaths

    • Surfacing.

    Refer to the maps page for more detailed views of Zone A.

  • Zone B: new road

    The four-lane median-separated motorway between the intersection of Halswell Junction and Springs Roads and the Curletts Road interchange with underpasses (local road over) at Awatea/Dunbars Road and Aidanfield Drive.

    • Construct new road
    • Earthworks
    • Landfill remediation
    • Build seven structures
    • Upgrade Springs Road roundabout.
    Sequence of work started in June 2010
    • Construction works generally east to west
    • Landfill monitoring
    • Establish sediment controls
    • Landfill treatments
    • East end drainage works
    • Remove topsoil
    • Bring in bulk fill at east end
    • Structures
    • Pavement construction
    • West end roundabouts
    • Surfacing in final stage.

    Refer to the maps page for more detailed views of Zone B.

  • Zone C: duplication

    The existing two-lane motorway between the Curletts Road interchange and Collins Street was duplicated to form a four-lane median-separated motorway with full access at Curletts Road and Barrington Street.

    • Clear site
    • Earthworks, including embankments
    • Build four major and two minor structures
    • Construct Curletts Road Interchange
    • Relocate services at east end.
    Sequence of work started in March 2010
    • Construction works generally east to west
    • Site clearance
    • Services relocation – east end
    • Ground improvements
    • Embankment fills
    • Major structures after settlement period
    • Minor structures
    • Pavement construction
    • Surfacing
    • Demolish Raceway Overpass.

    Refer to the maps page for more detailed views of Zone C.