O Mahurangi - Penlink

30 August 2024

Wēiti River Bridge update

As you may know, we are forecasting a delay to the Wēiti River Bridge component of the project of at least 12 months. The rest of the project is still on track for completion by late 2026, and will provide improved access to residents of Stillwater and others along the corridor.

We have already undertaken several initiatives to mitigate the programme delay, including design optimisation, construction methodology improvements, and forward resource planning. 

We acknowledge this is a significant delay and will be disappointing to the Whangaparāoa Peninsula community. However, we can assure you that the team is working efficiently and is continuing to explore initiatives to improve the programme. 

We expect to have more certainty on the implications of this delay in the coming months and will update you when we have more information. Thank you for your understanding as we work to establish an updated project programme.

Please reach out to us with any questions or comments by emailing us at omahurangi@nzta.govt.nz.

7 months of progress in 5 minutes

The team have made big progress over the last 7 months.

Check out the video above to see the changes taking place across site by comparing drone footage from November 2023 and June 2024.

(Left) Duck Creek Road bridge team pouring deck concrete with boom pump, (top right) team carrying out final reinforcing inspection, (bottom right) broom finish applied to bridge deck.

Duck Creek Road bridge taking shape

Work at the Duck Creek Road bridge is progressing well, with the structures team recently carrying out a successful concrete pour. Once complete, the Duck Creek Road bridge will be one of New Zealand's longest single span concrete bridges at 49 metres long and 12 metres wide, with two traffic lanes and a shared path.

This concrete deck pour is the first of five local bridges within the project. A local bridge is one that connects to local roads across the project versus the Wēiti River bridge, which has a large span across the river.

The Duck Creek Road bridge is being built using a top down construction method, meaning the piles and bridge deck are constructed first, then the earth is excavated from beneath it. 

The construction of the bridge deck started by placing 32 precast deck panels onto the bridge girders. Then 40 tonnes of deck reinforcing steel was placed on top of the panels by a team of 16 steel fixers, tying the girders and deck panels together.

On pour day, 27 concrete trucks delivered 125 cubic metres of concrete to the Duck Creek Road bridge site. A team of 8 concrete placers and a 49 metre concrete boom pump placed the deck concrete which was up to 250mm thick. The placing team completed the pour with a broom finish to the 600 square metres of bridge deck. All in all, the concrete pour took 10 hours to complete.

Wēiti River channel re-opening

Work to establish the temporary staging platform on the eastern side of Wēiti River has progressed well and the channel is now open. While the channel is open, vessels travelling upstream of the worksite will pass through a restricted navigable gap between the eastern and western sections of the temporary platform – see map above. 

During our working day as construction continues, loads will regularly be lifted over the navigable gap requiring the channel to be intermittently closed for short durations at these times. This is to keep all river users safe and ensure no vessel passes beneath a suspended load. 

Our working hours are Monday to Friday, 7am to 6pm, and Saturday 8am to 4pm.

Passage via the navigable gap within the construction zone

Key details for all private vessels including kayaks, stand-up paddle boards and dinghies are:

• Please follow all instructions from project team or signage in the area.
• Avoid passage if practicable during work hours.
• Notify the project via VHF CH73 to alert project team of your intentions. 
• Our project team will direct you accordingly via safety vessel and/ or hand signals.
• Do not pass underneath cranes (lifted loads) or booms across the channel.
• Maintain lookout for approaching or overtaking vessels.
• Do not attempt to pass through the gap at the same time as another vessel. 
• Give way to vessels travelling with the tidal current. 
• Rules of the Sea (power gives way to non-power, keep to the right/ starboard at all times) apply. 
• 5 knots at all times. 
• We ask vessels with a combined beam/width greater than 6m to contact the project team on 0800 PENLINK with a minimum 2 days notice. 
• We ask commercial operators and their clients to please follow specific protocols in the Navigational Passage Plan.      
• Please note: the above procedure does not relate to vessels navigating in the river downstream of the worksite.

Future temporary closures

Later this year, (November/December) a second temporary closure will be required. This will be for a shorter duration, 4 weeks of work, and will not affect the Christmas and New Year period.

This visualisation of the new O Mahurangi / Whangaparāoa Road intersection is an artist’s impression for illustrative purposes only. It may not be complete or fully accurate and should not be used for technical purposes.

Upgrading the Whangaparāoa intersection

Whangaparāoa is undergoing crucial improvements to create the future intersection of O Mahurangi at Whangaparāoa Road. The Whangaparāoa intersection is designed to enhance safety, traffic flow and stormwater management. Key improvements include:

• Addition of westbound lane after Cedar Terrace on Whangaparāoa Road to ensure future-proofed capacity for traffic from further up the peninsula.
• Left turns only in and out of Cedar Terrace, eliminating unsafe right turns.
• Extra lane length on Whangaparāoa Road for vehicles turning right to local roads (Wiriana Place, Beverley Road, etc.).

Stormwater wetlands will capture and treat stormwater run-off from road surfaces, reducing the risk of flooding in this low-lying area. Currently, flood waters go over the top of Whangaparāoa Road in a 1 in 10-year storm event. The new design will keep the intersection operating during a 1 in 100-year event, and the wetland areas will also feature ponds, landscaping and pathways. 

Construction of the new intersection is underway and taking place next to the existing road, to allow traffic to continue to use Whangaparāoa Road. 

Temporary traffic management will be in place and we expect there to be some impacts when transporting goods to site and later when connecting the new road to existing infrastructure. However, our work has been carefully planned to keep disruption to Whangaparāoa Road to a minimum. We thank you for your patience during this time and apologise for any inconvenience caused.

At this stage, the new road alignment at Whangaparāoa Road will be complete by late 2026, however the traffic signals will not be operational and a barrier will be put in place to avoid access onto the completed section of road until the bridge portion of O Mahurangi Penlink is complete.

Various Girls with High Vis site visit activities and group photo next to the Duck Creek Road Bridge.

Girls with High Vis visit

We recently hosted 13 secondary school students from Girls with High Vis for an informative and engaging site visit. The Girls with High Vis initiative gives female students around the country the opportunity to gain hands-on experience, hear from inspirational women in the industry and learn what a career in the infrastructure industries, as well as other important trade sectors, can offer.

The visit saw the students get construction-site ready with boots, hard hats, safety glasses and safety vests. After a site induction, they split into groups to rotate through four stations. The activities at the stations were planned to showcase different parts of the project:

• 2 engineers led an activity at the Wēiti River site where they went out on to the temporary staging and practiced marking up head stock (pier caps).
• A surveying activity where the girls got to take a scan of the bridge and learned more about how survey equpiment works from our site surveyor.
• 2 engineers led an earthworks activity where they learned how to use a shear vane, an essential tool to ensure fill areas meet their designed strength.
• 2 traffic engineers led a traffic activity with a 3-way Stop-Go traffic management system where they discussed the risks and importance of having traffic management in place.

Auckland Councillor Angela Dalton provided a talk and encouraged them to consider a career in a traditionally male-dominated field. The group then participated in a question and answer session with some of our female project engineers. At the end of the visit, the students said they had a better understanding of infrastructure and what future possibilities the industry offered. Survey results revealed that before the event most students only knew ‘a little’ about infrastructure. After the event, almost all said ‘yes, I better understand what infrastructure is.’

More information

For more information on the O Mahurangi project, contact us at omahurangi@nzta.govt.nz or call us on 0800 7365 465.

Visit our website www.nzta.govt.nz/penlink