Gridlock city, again
The slip that shut down Wellington’s roads on Monday could barely even be considered a slip.
It was at most three wheelbarrow loads of dirt, most of which wasn’t even on the road. It took more than four hours for contractors to reopen the lane, because the bank alongside the road was threatening to give way and needed to be secured using a large excavator.
In that time, as many as 46,000 vehicles were delayed or stuck. Traffic stopped for kilometres, as issues piled on top of each other and pushed through the CBD, locking up almost every street in the city.
‘‘It was a shocker,’’ Hutt South MP Chris Bishop said. ‘‘It shows the lack of resilience in the network, one tiny slip and it cuts off the whole Hutt.’’
Wellington Mayor Andy Foster said Monday’s chaos was evidence of how vulnerable the city’s transport was. ‘‘The way traffic was backed up through The Terrace and all the way to the eastern suburbs, it shows how one small thing can have a cascading effect that affects the whole city.’’
Both Bishop and Foster said the traffic showed the urgent need for the proposed Petone to Grenada link road. ‘‘[State Highway 2] is a particularly vulnerable road and we have a very small number of options for alternative routes throughout the region,’’ Foster said.
The Petone to Grenada highway was a top priority in the Wellington Lifelines report, which recommended a $5.3 billion investment in the region’s infrastructure to safeguard New Zealand’s economy in the event of a magnitude-7.5 earthquake on the Wellington Faultline.
The link road would connect Seaview on the eastern side of Hutt Valley to SH2 on the western side. The report recommends the road be built by at least 2029, and be constructed so it was usable following a quake.
The highway was put on ice shortly after the Labour-led Government came to power in 2017.
However, in 2019, the New Zealand Transport Agency said it would reconsider the road, though the project would need to be redesigned and funding for its construction would not be considered until 2028.
Timeline of a traffic jam
Stuff spoke to several commuters who said Monday was some of the worst traffic they had ever encountered.
It took Sophie Jolley half an hour to get 300 metres from The Terrace offramp to Boulcott St.
Wellington’s congestion on Monday, as shown on Google Maps, with the standstill jams shown in red.
Nearby, at the corner of Boulcott and Willis streets, one driver complained of being stuck in one spot for 20 minutes.
Kelly Fox said it took four hours and 40 minutes to get from Wellington to Levin, a journey that normally takes an hour and 15 minutes.
Many central city car parks had long lines just to get out onto the road.
Bishop was among the thousands of Wellingtonians who had issues getting home. He had to cancel an event due to a projected 110-minute drive between Parliament and the Hutt Valley.
The first reports of the slip came in at 2.50pm, more than 60 minutes before rush hour was due to start. The first crew was on the scene to assess the situation at 2.56pm, and traffic management arrived at 3.10pm to close off one lane.
Almost immediately, traffic started backing up and NZTA warned of significant delays. Within 10 minutes, the traffic jam stretched back 4km to the Ngauranga Interchange.
Contractors reached the site at 3.55pm but soon discovered that the blockage on the road was only the start of their problem. The bank running alongside the highway was unstable and would need to be stabilised before the left lane could open again.
‘‘Although most people would have only seen a small amount of material that had come down, there was a larger volume of loose material higher up the slope which posed a high risk,’’ NZTA’s Mark Owens said. ‘‘A large excavator was required to safely clear the loose material and [for] that we would need to get a standover permit from Wellington Electrical for this work, due to the close proximity of overhead power wires.’’
Three truckloads-worth of debris that wasn’t on the road also had to be removed, as it was deemed to be a further risk.
Getting the excavator to the site proved tricky, and it spent over an hour stuck in traffic before it could reach the slip and set to work solving the issue. Both lanes of the road were briefly closed for 10 minutes before 4pm to let crews remove dirt. By the time the road reopened at 4.05pm, still only one lane, traffic was stalled all the way to the Terrace Tunnel 10km away, and along Ngauranga Gorge.
NZTA put out an all-caps warning for people to ‘‘DELAY YOUR TRAVEL’’ or consider going via Porirua using SH1 and SH58. For a Hutt-based commuter, that would turn a 15km journey into almost 50km. It didn’t take long for that route to be overwhelmed.
At 4.55pm, NZTA warned of significant delays on both state highways. It was about the same time that the excavator finally arrived at the slip and set to work clearing debris.
At 5.45, almost three hours after the initial slip, traffic had not improved.
The excavator finished clearing the slip area at 6.55pm, allowing two lanes to open but it took time for traffic to ease. By 8pm, the highway finally returned to normal.