A moveable concrete barrier similar to one that is going to be used on the M20 has been reducing traffic congestion in New Zealand for 30 years.

The government confirmed yesterday the technology will be available in Kent by the end of the year to help minimise disruption if there are cross-Channel delays.

See the moveable barrier in action on the Auckland Harbour Bridge

KentOnline has been in contact with the New Zealand Transport Agency to find out how they use a barrier to control traffic flow on the Auckland Harbour Bridge.

The bridge is eight lanes wide and is used by around 180,000 vehicles every single day. The barrier increases increase the number of lanes in or out of the city at peak times.

Andrea Williamson is Auckland system manager at Waka Kotahi, the New Zealand Transport Agency, she said: "Our barriers are moved four times a day.

"In the morning peak, we have 5 lanes coming into Auckland city, and we have 3 lanes heading north out of the city.

"In the middle of the day we've got four lanes in each direction. And in the evening peak, we've got five lanes exiting the city and three lanes coming into town.

"It takes about 20 minutes to do a full shift [of the barrier].

"There are two machines based on each side of the bridge, and we've always got one machine available as a back-up just in case of mechanical failure."

We exclusively revealed ministers had given the green light for the system to be used in Kent, instead of the controversial Operation Brock contraflow which was set up in preparation for Brexit.

The Department for Transport said the barrier would be a marked improvement and can be implemented within hours rather than weeks.

Andrea added "Safety is very important to us, and we've not had a head-on crash since the barrier was installed way back in 1990. It allows for more cars to get over the bridge, hence speeding up journey times.

"There is significant cost for purchase, operation and renewal of the barriers and the machines.

"They are all made and produced in the [United] States, and that costs a lot of money to get them over to New Zealand.

"However, the safety and congestion benefits that come from protection for opposing traffic, and improved traffic flow, are way greater than the cost.

"The traffic control required each day is also very labour-intensive, as we have to put lane closures out every day in advance of the barrier move."

Moveable barriers are also in use in Sydney, San Francisco and Vancouver.

The cost of the system that'll be deployed in Kent hasn't been revealed but is expected to run into millions of pounds.

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