Motorists were charged new tolls on Monday at the three cross-harbour tunnels in a bid to ease traffic congestion.

“We apologise to the drivers who were charged the wrong tunnel fees,” Lee said.

She added that from 7am to 11am, 64,000 vehicles passed through the three crossings. Traffic at the Western Harbour Tunnel slightly increased, while the number of vehicles at the other two crossings saw a drop.

She also noted that more vehicles crossed the three links before 7.30am, when peak-hour charges kicked in.

The Western crossing was the only tunnel that had a major glitch, according to Lee. Seventy per cent of the affected drivers, or about 3,400, were refunded while the rest were notified of the new charges.

A tunnel employee using a previous charging scheme was behind the mistake, Lee said.

Private cars passing through the tunnel are charged up to HK$60 (US$7) between 7.30am and 10.15am. But the fee is gradually halved to HK$30 between 10.15am and 4.30pm.

Hong Kong to bring in time-varying tolls at 3 harbour crossings in December

Lawmaker Gary Zhang Xinyu said driving from West Kowloon to Hong Kong Island via the Western crossing at 10.22am cost him HK$60 when he was supposed to pay HK$52.

“I didn’t notice the situation until some drivers told me they were overcharged,” he said. “The tunnel operator promised to refund me.”

Peak hour traffic on Monday evening was lighter than usual. It took a Post reporter who took a taxi ride from Times Square in Causeway Bay to Kowloon via the Cross-Harbour Tunnel at 6.40pm two minutes to get into the crossing, compared with 17 minutes on the same trip at the same time and place on Friday.

Earlier in the morning, driving through Hong Kong’s busiest cross-harbour tunnel took less time during the peak hours, motorists said.

Hong Kong’s Cross-Harbour Tunnel to adopt new electronic toll system on Sunday

Traffic flowed smoothly on the first working day of the second phase of the toll adjustment scheme, under which private cars using the Cross-Harbour Tunnel, the Eastern Harbour Tunnel and the Western Harbour Tunnel pay varying charges depending on the time of day, according to transport officials.

Ringo Lee Yiu-pui, the honorary life president of the Hong Kong Automobile Association, said that it took him seven minutes to travel through the Cross-Harbour Tunnel to Wan Chai at around 7.30am, three minutes faster than previous Monday commutes.

“The traffic this morning was relatively smooth and acceptable given the Cross-Harbour Tunnel used to be the cheapest and most congested one,” Lee said.

Wong Lik-kei, 38, an investment banker who drove from Tai Po to Central for work using the Cross-Harbour Tunnel at 8.30am, said it was about 10 minutes faster than usual weekdays.

“Heavy traffic only started to appear as I approached the tunnel at around 8.30am,” Wong said. “During previous weekdays, the queue extended all the way to the footbridge of Oi Man Estate [about 2km away]. It didn’t happen this morning.

“I find the situation acceptable. After all, it is simply a matter of paying for convenience with money.”

Traffic jams at 2 Hong Kong tunnels will shrink after toll changes: authorities

Under the new toll arrangement in effect since Sunday, private cars will be charged up to HK$40 (US$5) at the Cross-Harbour Tunnel and the Eastern Crossing during peak hours from 7.30am to 10.15am and from 4.30pm to 7pm between Mondays and Saturdays. At the Western Harbour Tunnel, charges can reach up to HK$60.

The fees will progressively increase by HK$2 every two minutes from a peak-hour slot up to the maximum amount. The opposite arrangement will occur for off-peak periods.

All three tunnels charge HK$30 for private cars for the period between 10.15am and 4.30pm and HK$20 for the off-peak hours between 7pm and 7.30am the next day.

Phase one of the toll changes came into force on August 2 when tolls were lowered at the Western Harbour Tunnel and increased at the two busier tunnels.

Lee from the Automobile Association left Wan Chai at around 8.30am and headed to Tsuen Wan via the most expensive cross-harbour link in the city.

“After exiting the tunnel, I saw a long queue at the Kowloon entrance [of the Western Harbour Tunnel],” he said. “To me, that was a sign that some traffic from the Cross-Harbour Tunnel was diverted to the Western Harbour Tunnel due to the new time-varying toll arrangement.”

He urged motorists to prioritise safety and refrain from suddenly slowing down or speeding up to take advantage of the progressive toll arrangement during peak hours.

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“If drivers want to save money, they should consider travelling during non-peak hours,” Lee said. “If it is necessary to pass through the tunnel during peak hours, they should not be too concerned about the minor fluctuations of HK$2.”

Transport minister Lam Sai-hung visited the Western Harbour Tunnel in the morning and said there were no significant traffic congestion or disruptions up to 8am in the three tunnels.

“We observe how the time-varying toll system works and the toll fee display screens are functioning properly,” he said.

“Our colleagues from the Transport Department and I will also inspect the afternoon operations and monitor the situation for future cross-harbour tunnel crossings.”