Toll sensors capture the vehicle's type and size and take an image of both the front and rear licence plates, noting the time and date passed through, then assign the correct toll tariff.
The e-system uses automatic number plate recognition, and the method of payment collection and debt repayment is either via online accounts, bank direct debits, or managed accounts for commercial users, casual online prepay and post payment or cash.
If payment is not made within five days of the trip, it results in penalties plus the possibility of an infringement notice being sent to the defaulter.
NZTA tolling manager Andrew Thackwray told councillors a move to free-flow electronic tolling for Route K had significant advantages, in upfront costs and price flexibility. The $10 million cost of buying one gantry could be halved if bulk buying two at the same time.
Mr Thackwray said the centrally managed system offered a much quicker and safer alternative, and it made sense to e-toll Route K as well as the Tauranga eastern arterial for consistency and parity.
"With no toll booths to stop at, it means the motorist's trip is uninterrupted, there is no hunting for loose change, and motorists can pre-plan and pre-pay their trips," he said.
Mr Thackwray said some of the successes of the northern gateway free-flow toll road system included achieving just under 97 per cent compliance rate, with just under 90 per cent of toll revenue collected within five days of a trip.
Mayor Stuart Crosby said he and most of the councillors agreed the proposed move made sense, but it was just part of a discussion with NZTA about how the council could progress both Route K and Turret Rd/State Highway 2A issues.
That included discussions about changing the status of Route K to a state highway.
Mr Crosby said one of the big positives in electronic tolling for Route K was that it would come at no extra debt cost to Tauranga ratepayers.
Route K's $60 million debt had steadily grown over the years and was now a significant part of council's overall debt of $400 million. Each year about $2 million was added to the bill due to the shortfall in tolls.
Mr Crosby said NZTA rules prevented the government agency from taking over the existing debt, and the council had been exploring ways to try to reduce the risk to ratepayers.
Other discussions included looking into the NZTA taking over the maintenance cost of Route K.
Mr Crosby said no decisions had been made and the community would be consulted.