The holiday weekend has claimed its first road fatality after a motorist died when a car crashed into a ditch near Turangi.
The crash brought power lines across State Highway 47. Emergency services were called about 5.40pm tonight.
A police spokeswoman said three people were believed to be in the car at the time of the crash.
Two were out of the car when police arrived but one was trapped in the wreckage.
That patient has since died at the scene.
One of the other two passengers is being airlifted to hospital in a serious condition.
Police are diverting traffic. SH47 is completed blocked, about 900m south of SH41
The death is the first of the three-day Queen's Birthday weekend, which began at 4pm today and ends at 6am on Tuesday.
Four people died during the holiday weekend last year.
Three people are in hospital tonight after a two-car smash at West Melton on West Coast Rd.
Traffic has been diverted. The accident happened about 7.55pm.
One person suffered serious injuries while two have moderate injuries.
They were all transported to Christchurch Hospital.
One person was initially trapped, however Fire and Emergency managed to get them out.
Police are investigating.
Meanwhile, heavy traffic and a series crashes earlier today caused serious congestion and delays as thousands of holidaymakers left town for the three-day Queen's Birthday weekend.
State Highway 1 north of Auckland has reopened after a fatal crash earlier closed traffic in both directions, with motorists saying traffic on a diversion road was "almost at a standstill".
The NZ Transport Agency also reported queues on the main highway north out of Wellington and SH2 was blocked in both directions following a crash at Trentham at Moonshine Rd.
"Please expect delays and follow directions of emergency services," NZTA warned on Twitter. The crash was later cleared.
Another crash blocked the right southbound lane at Horokiwi on SH2 this evening, prompting warnings for motorists to pass with care and expect delays.
As holiday travellers combined with peak home-time traffic, all of Auckland's motorways were carrying heavy flows, with a series of crashes and breakdowns causing further delays.
North of Auckland, one lane of SH1 is now open in each direction at the site of a fatal crash north of Te Hana, which happened this morning, though a passing lane would remain closed overnight.
Traffic had been diverted onto other roads to bypass the crash site while the police completed their investigations.
But the detour route became congested because of roadworks.
A motorist told the Herald: "I'm heading south and big backlog from one-lane roadworks 5km south of Mangawhai. And heading north seriously ugly."
Another said the delays were appalling.
"Although SH1 is now flowing smoothly after a four hour road closure ... the same cannot be said for the diversionary road.
"Because of the Queen's Birthday holiday, traffic heading north was bumper to bumper on the main road, and is now nose to tail and almost at a stand still on the only road that bypasses the area.
"Motorists who found themselves inadvertently caught in the slow crawl are justified in asking the police why the major road north was closed for as long as it was, and why no traffic management was evident once the road was reopened."
The Transport Agency said the roadworks were on Mangawhai Rd, part of the detour route.
"They stopped work on the roadworks to make it easier for people to get through."
Meanwhile, SH1 past the Lemons Hill slip in the Bay of Islands will remains open round the clock over the long weekend. However the road will be reduced to one lane under stop/go management, NZTA said.
"The long weekend will bring more visitors to the area who will want to travel on the state highway between Paihia and Kawakawa. There's also the Paihia half marathon on Sunday so we expect there will be higher than normal weekend traffic on the road.
"We urge motorists to drive with care and keep to the speed limit past the slip to ensure the safety of the stop/go operators and all road users, says Ms Hori-Hoult."
Over size vehicles would still have to use the detour route via SH1, 10 and 11. Drivers should allow up to 30 minutes extra for the journey between Kawakawa and Paihia.
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