TNOC Coordinated Maintenance Activity Closures

11/03/2025

For the past four maintenance seasons, TNOC has been regularly running multi-activity road closures across the Taranaki state highway network.

The SH3 corridor north of Taranaki in particular is an essential access route for the region, and maintaining risk-prone areas such as the Awakino Gorge and Mt Messenger is a key focus for TNOC.

Due to increased TTM and health and safety requirements, alongside the narrow and winding nature of Taranaki state highways; closing the road was soon identified as an effective means to complete a large amount of maintenance work in a cost-efficient way, while condensing disruption for stakeholders, and keeping everyone safe. Ongoing consultation and engagement with stakeholders since 2021-2022 confirm this approach as the least disruptive and most preferred.

SH3 Mt Messenger Asphalt Resurfacing: 2x three-day, 24/7, road closures, April & November 2024
To maintain the resilience of SH3 Mt Messenger until the Mt Messenger Bypass project is completed TNOC was tasked with resurfacing April & November 2024 nearly 6 Kilometres of Mt Messenger with asphalt.

The work was completed in two stages, scheduled in April and November 2024, to balance both funding and journey management impacts. Careful advanced planning was undertaken by the team to ensure efficient delivery while best minimising disruption for road users and the community.

Ongoing stakeholder consultation informed the “short and sharp” approach to the closures, with three days (57 hours) of 24/7 weekend closures, with stop/go and shorter closures during the nights either side. During the 24/7 weekend closures, scheduled openings were in place to keep travellers moving along this key access route for Taranaki.

TNOC collaborated with consultants as well as the Mt Messenger Bypass Alliance to maximize works during the closures, with activities such as bridge inspections, as well as the transportation of specialist machinery for the Mt Messenger Bypass. Multiple crews were recruited from regions such as Taumarunui and Hawkes Bay to assist with delivery of the asphalt resurfacing, and other essential maintenance activities.

• ~3,500 ton of asphalt paved over two three-day closures
• Three asphalt crews worked 24/7 shifts to complete prepping, milling and paving.
• 200+ staff onsite over the course of the closure, completing activities including crack-sealing, AC levelling, guardrail repairs, tree removal, fence repairs and the transportation of the Mt Messenger Bypass specialist Tunnel Road Header machine.
• Three TTM crews.
• More than 30 vehicles, plant and machinery operating at any given time.

The approach reduced the construction period and disruption for stakeholders to two condensed bursts of high impact. Under traditional stop/go, this large quantity of work would have taken 6-8 weeks to complete.

“By working with TNOC, the Alliance was able to undertake 6 activities during the closure, including the transportation of the Tunnel Road Header which otherwise, would have required a separate road closure. We estimate that we reduced traffic management by 66 hours, minimising the disruption to motorist and improving their journey experience.”
– Peter Lawn, Operations Manager, MTM Alliance

The innovative approach of coordinated closures achieves a significantly condensed construction period, resulting in several positive outcomes:

• Reduced costs of site establishment & disestablishment.
• Reduced costs of temporary traffic management crews.
• Enhanced journey management outcomes by way of minimising impact to key stakeholders, road users and the local community.
• Increased safety of both crews and road users alike.
• The resurfacing work was completed one week ahead of schedule.

SH3 Awakino Gorge Maintenance: 3x days of closures 9.30am to 2.30pm, December 2024
Work was completed under a series of full closures and stop/go, with closure timings informed by stakeholder feedback and traffic flow data during the planning stages of the works.

Starting in 2021-2022, the maintenance closure has become an annual occurrence, designed to complete each season’s pre-reseal repairs, slip clearance, signage and drainage repairs, and reseals.

• 5780 square metres of pavement repairs (stabilisations and digouts) completed.
• 4,000m2 of crack sealing completed.
• 1500 signs cleaned, repaired or replaced, alongside guardrails, over 9Km of state highway.
• 4,000m of roadside cleared of litter.
• 620m of roadside cleared of slip material/debris.
• 4.15km of surface water channel clearing.
• Eight crews working within the closure across multiple activities using 32 trucks and plant.
• Six TTM crews to facilitate.

Work was completed under a series of full closures and stop/go, with closure timings informed by stakeholder feedback and traffic flow data during the planning stages of the works.

Coordinating multiple activities in one closure reduced the overall construction period to five days, including the stop/go periods. Completing this work under traditional stop/go could have taken up to eight weeks.

• 35% cost savings in traffic management.
• 70-75% reduction in construction period.