More than 900 drivers have been wrongly issued with fees this year because vehicle registration plates were misread on southeast Queensland toll roads.
At this rate, by Christmas more than 1300 drivers would have received an incorrect toll notice to say their vehicle had been spotted in the Clem7 tunnel, on the Go Between Bridge or on the Gateway and Logan motorways.
Lord Mayor Graham Quirk yesterday waived the fine of Cairns woman Sue Brennan who left her car at Cairns airport but was wrongly fined for "driving" over Brisbane's Go Between Bridge.
The Go Between Bridge. Photo: Glenn Hunt
However, the technology used by all tollways was more than 99.99 per cent accurate, all operators said.
On the Go Between Bridge there had been 213 misreads since January 1, representing a 99.992 per cent accuracy rate on the 2.4 million trips over the Go Between Bridge, the council said.
On the Clem7 tunnel there have been about 275 misreads after motorists made five million trips since January 1, according to RiverCity Motorway.
Clem7 operator RiverCity Motorway said it had "five to six misreads" for every 100,000 vehicles.
RiverCity Motorway chief executive Mark Snape said the technology was 99.995 per cent accurate.
“RiverCity Motorway uses a combination of advanced optical recognition technology using cameras at tolling points," Mr Snape said.
"We use a manual image review by a member of our team to process tolls for vehicles that travel through the Clem7 where a valid tag is not detected.
"The combined error rate across both automated and manual image review is five to six per 100,000 vehicles, which represents a 99.995 per cent accuracy rate on all vehicles that use the Clem7 where a valid tag is not detected."
On the Queensland Motorways network of Gateway and Logan motorways there are 200,000 vehicles each day.
Queensland Motorways chief executive Brendan Bourke said he could not estimate an exact figure, but said the company's number plate recognition standards were similar to Clem7 and the Go Between Bridge of around 5.5 "misreads" per 100,000 vehicles.
Based on an estimate of the 40,000 vehicles each day who are "manually checked" each day by an operator there would be about 450 misreads in the first seven months of this year.
Cr Quirk yesterday waived the fine of Ms Brennan, now living in Townsville, who was wrongly issued with a toll for driving her car over Brisbane's Go Between Bridge.
Go Between Bridge toll operators manually review about 500 images an hour, after the automatic system locks in on the front and back registration plates.
Cr Quirk said "human error" happened when the number plate information was manually written down for the bill when the error occurred.
"It doesn't happen very frequently, at all," Cr Quirk said.
"There are certainly cases where it does happen and it is simply human error."
"It is a case of transferring the photographic evidence to the paper where a bill is sent out to people.
"Human error occurs. We all make mistakes from time to time."
Last night, Ms Brennan said she was shocked by the figures detailing how many number plates had been misread since January 1.
"Wow. If you have got that information after one day after the article, it makes me wonder what sort of figures you will have after a week's time, or maybe a month's time," she said.
Ms Brennan said there needed to be a new look at how the manual checking stage worked.
Last year, the NSW Roads and Traffic Authority revealed some 14,000 fines were incorrectly issued. At the time, operator mistakes were also blamed.
How they read the number plate on the Go Between Bridge
- When a vehicle crosses the tolling point, images of both the front and rear number plates are taken.
- Optical Character Recognition is then performed on those images and a “confidence level” is assigned by the system which rates the certainty that each character is correct.
- If there is a match between the front and rear licence plate numbers, and the confidence level exceeds a certain limit, then the number is locked in.
- Otherwise the image is placed into a queue for manual review by an operator who will confirm the LPN.
- Skilled operators can review up to 500 images an hour, and as with any manual process, human error can occur.