Bus and Coach Association Notifications

Construction Update April 2017: Southern Corridor Improvements

Wednesday, 12 April 2017

Welcome to the April 2017 construction update for the New Zealand Transport Agency's

Southern Corridor Improvements Project

This update outlines what works we achieved in March and provides details on what we have planned for April. Photos of progress are provided at the bottom of the update.

PROGRESS THROUGH MARCH

Despite the wet weather over the last month, we continued to focus on completing the additional southbound lane from the Hill Road off-ramp to the Takanini off-ramp, and between the Takanini on-ramp and Pahurehure Inlet.

At Takanini, temporary lane changes southbound enabled the establishment of a safe work zone for bridge works over Papakura Stream. By breaking the concrete edge of the old bridge, the area was ready for concrete to be poured and the old and new bridges were connected together.

We continued installing temporary traffic management northbound from the Papakura Interchange to Pahurehure Inlet. With narrowed lanes and an 80kph reduced speed limit established both northbound and southbound, the work zone has been extended to accommodate safe works in the median.

Below is a summary of our activities in March:

Hill Road to Takanini Interchange:

• Retaining wall and noise wall construction continued along the southbound shoulder from Hill Road to the Takanini Interchange.
• Under the Hill Road Bridge, formwork was constructed to shape the median bridge pier protection and support the poured concrete while it set.
• Under the Alfriston Road Bridge, the motorway continues to be lowered to increase the overhead clearance height for large vehicles. Earthworks began in the median to prepare for new materials that form a compact and stable surface for asphalt.
• North of the Takanini southbound off-ramp, the two motorway lanes were separated to create a safe work zone between them to accomodate bridge works.
• At Fergusson Reserve, we started importing soil and stockpiling it to prepare for construction of the new Takanini northbound on-ramp. Better quality, compacted soil and granular materials will form a stable surface for the new northbound on-ramp.

Takanini Interchange to Pahurehure Inlet:

• Sub-soil drainage works were completed along the southbound shoulder to connect between the new and old stormwater drains.
• In the southbound shoulder, pavement works are ongoing. Compacted granular materials will form a stable support for the asphalt layer, which will complete the pavement surface required to open the additional southbound lane to traffic.
• Vegetation clearance continues along the northbound shoulder in preparation for drainage works and noise wall construction.
• Retaining wall and noise wall construction commenced along the northbound shoulder. This work will continue throughout 2017.

UPCOMING WORKS IN APRIL

Final works along the additional third southbound lane will be complete before it opens to traffic later this month. On SH1 southbound, the additional lane will run from the Hill Road off-ramp to the Takanini off-ramp, and between the Takanini on-ramp and 300m north of the Pahurehure Inlet. Reduced speed limits and narrowed lanes will remain in place while we complete works along the shoulders and at the Takanini Interchange.

The new Takanini southbound off-ramp was connected to the existing bridge on the 1^st April. For this to take place, a 12 hour southbound motorway closure was necessary to allow the poured concrete to cure and gain sufficient strength and avoid vibration from passing vehicles.

Orams Road Bridge will be closed to all traffic from Saturday 22 April until October 2017. The eastern span of the bridge needs to be demolished and a longer span constructed in order to widen the SH1 southbound carriageway for an additional fourth lane from SH20 to Hill Road. More information about the closure can be found on our website http://nzta.govt.nz/projects/southern-corridor-improvements/media under the heading Updates.

Below is a summary of what we have planned for April:

Hill Road to Takanini Interchange:

Preparation for the demolition of Orams Road Bridge begins.

Work continues under Alfriston Road Bridge. This includes laying permanent asphalt, pouring concrete to create new median barriers and installing a new southbound gantry. We will also complete new drainage lines under the motorway.

Asphalting continues in the southbound shoulder. This is one of the last activities prior to opening the additional (third) southbound lane from Hill Road to Pahurehure Inlet (excluding Takanini).

Earthworks and drainage continue along the southbound shoulder.

The new Takanini southbound off-ramp was connected to the existing Papakura Stream Bridge during an overnight concrete pour on Saturday 1 April.

At the northbound Papakura Stream Bridge, sheet piling will occur to prepare for the construction of new bridge abutments.

Takanini Interchange:

• Temporary traffic management will be installed along Great South Road to support the widening of the motorway at Takanini Interchange and construction of the new northbound on-ramp.
• Works to prepare for upgrading the northbound on-ramp and off-ramps are underway. This includes construction of a track off Great South Road to allow construction access to the inside of the existing loop. Installation of erosion and sediment controls such as decanting earth bunds and silt fences will follow. Topsoil will be stripped inside the existing loop.
• To widen the southbound bridge over Great South Road, preparation for piling works will begin.
• Along the new northbound on-ramp, sheet piling for the retaining wall will begin. Piling and pier construction on the northbound bridges over the railway advances.

Takanini Interchange to Pahurehure Inlet:

• Asphalting will continue in the southbound shoulder to complete the additional lane scheduled to open to traffic later this month.
• Vegetation clearance will continue along the northbound shoulder in preparation for drainage works and noise wall construction, which is also underway in some areas.

Pahurehure Inlet to Papakura Interchange:

• Between the Pahurehure Inlet Bridges, earthworks will begin to strip back the topsoil and remove the top layer of dirt in order to prepare the area for granular materials. This will improve compaction and ensure the new road surface remains stable.
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PROGRESS PHOTOS

Box cut in the median at Alfriston Road Bridge looking south. The previously grassed median has been excavated and new materials have been compacted, prior to asphalting.

New noise wall panels and subsoil works preparing the southbound lanes for asphalting. Asphalting is now almost complete. This is one of the last activities required before opening the new additional (third) lane from Hill Road to the Takanini southbound off-ramp and from the Takanini southbound on-ramp to Pahurehure Inlet.

At the start of April, the new Takanini southbound off-ramp was connected to the existing southbound bridge. On the northern side of the motorway, works have begun in Fergusson Reserve to prepare for the new Takanini northbound on-ramp.

A major milestone for the team in March was the completion of the retaining wall along the new southbound off-ramp at the Takanini Interchange, over the rail carriageway.

The new southbound off-ramp at Takanini Interchange will be open to traffic towards the end of April.

Orams Road Bridge will be closed for five months from 22 April until October 2017, in order to demolish the eastern span and construct a longer bridge deck to accommodate four southbound motorway lanes.

Traffic management was installed southbound and northbound between Papakura Interchange and Pahurehure Inlet to enable earthworks to begin in the median.

With narrowed lanes, there is less time to react to other vehicles and it is important that motorists keep to the 80 km/h speed limit past our work areas. There will be ongoing truck and construction vehicle movements accessing the shoulder and the median work sites. Keeping both motorists and our team members as safe as possible is imperative and we need everyone's help to do this.

As always, we will be doing our best to minimise effects of these works on motorists as much as we can. We thank you for your patience as we work to improve journey reliability and safety along the Southern Corridor.

You can read more background information and find out more about the project through the NZTA website, www.nzta.govt.nz/auckland-southern-corridor.

If you have any questions or queries, please contact our team on free phone 0508 NZTA SCI (0508 698 2724) or email us at southerncorridor@nzta.govt.nz. Also feel free to visit us at the Project Office located at 8-12 Great South Road, Takanini.