The controversial split-weigh stations north of Rakaia are progressing despite safety concerns.

Transporting New Zealand industry advisor Jim Crouchley said he “still has serious concerns over the location and safety issues" of creating the two centres on a busy stretch of State Highway 1.

“We have now had to go into a wait-and-see position and hope that motorists stay safe once this project is completed,” he told the Ashburton District Road Safety Co-ordinating Committee.

Construction of the southbound Commercial Vehicle Safety Centre, between the rail overbridge and the Rakaia River Bridge, is expected to be finished by February 2024.

A NZ Transport Agency Waka Kotahi spokesperson said this would be followed by Weigh in Motion (WIM) and weighbridge calibration and testing technology.

The site is expected to be fully operational by mid-2024, with the decision on when it opens in the hands of police.

The northbound centre, north of the rail overbidge, is in the design and consent application phase, with construction expected to start “possibly by mid-2024”.

The final design for the split centres includes a variable intersection speed zone, which has signs to reduce the speed limit on the highway to 60kph when a vehicle is exiting North Rakaia Road (heading south) or Weavers Road (heading north).

The speed across the Rakaia River Bridge will be permanently reduced to 80kph in the new year.

“A road safety audit on the site has been done to confirm its safeness for all road users.”

According to NZTA, an average of 70 heavy vehicles pass the Rakaia location every hour.

“It is estimated that between 4-6% of heavy vehicles would be flagged by the weigh-in-motion device and requested to enter the facility, based on current levels of compliance.”

That would equate to around three to five trucks per hour using one of the centres.

“The number of trucks affected will be limited to the capacity of the site, which can only accommodate about 10 trucks at once.

“It takes about 10 minutes for each truck to go through the site, so a maximum of six trucks can be processed each hour.”

The police safety team operating the site will also have the ability to enforce an ‘all trucks stop’ operation.

“They would monitor, manage, and mitigate any vehicle queues and any adverse impact to other road users.”

Bridge delays

In recent weeks there has been a crash and a breakdown on the SH1 Rakaia River Bridge causing its closure and resulting in major traffic disruption.

NZTA figures show in the last 12 months there have been seven crashes or breakdowns on the bridge causing delays.

“These delays in general would be up to about an hour,” an NZTA spokesperson said.

There have been no serious crashes in the last 12 months that require a four to eight-hour closure.

The last serious injury crash was in October 2021 – when a motorcyclist died after a crash involving a truck on the bridge at Labour weekend.

“In the last 12 months, there have been nine call-outs for the maintenance team to attend to debris or similar items needing to be removed from the bridge.

“This delays drivers for a short time – up to 15 minutes while it is cleaned up.”

By Jonathan Leask