SINGAPORE - The Immigration and Checkpoints Authority (ICA) will work with Changi Airport Group to divert arriving passengers to another immigration hall within Terminal 3 to alleviate congestion should several flights land around the same time.

The move comes after some passengers complained about long waiting times to go through immigration as the number of travellers grows due to the expansion of a quarantine-free travel scheme.

ICA has also reopened automated arrival lanes at Changi Airport from Friday (Oct 29) to speed up faster immigration clearance for travellers.

These automated lanes were closed due to new clearance processes arising from the pandemic. For example, immigration officers had to conduct manual checks to ensure a passenger's declared travel history tallied with the travel lane he was on, ICA said in response to queries.

But ICA has since integrated these checks into its entry application and immigration processes, which allowed it to reopen the automated lanes.

For instance, the integration of the verification digital vaccination certificate via the SafeTravel portal has enabled officers to verify the vaccination status of travellers before they arrive in Singapore.

While ICA is streamlining its processes, the overall time needed before a passenger can leave the airport will still be longer compared with before the Covid-19 pandemic, Home Affairs and Law Minister K. Shanmugam told reporters in a virtual interview after his visit to the airport on Friday morning.

"With increase in traveller volume, requirement for testing, clearances may take longer, and particularly if several flights arrive in quick succession," he said.

Changi has seen passenger arrivals grow following the start of eight new Vaccinated Travel Lanes (VTLs) this month with countries such as the United States and Britain.

Mr Shanmugam, who observed the process to clear passengers from four VTL flights, said passengers who submitted their declarations online took about 20 to 30 seconds to clear immigration using the automated lanes.

It will take about eight to 10 minutes for those who cannot use the automated lanes and have to go through immigration counters, such as very young children or tourists, he noted.

But the process could take a lot longer should a cluster of flights arrive together, a situation known as bunching-up.

There was an instance last week when travellers took about 90 minutes to clear immigration after five flights arrived at around the same time.

Mr Shanmugam said many passengers had not pre-filled their immigration forms.

"They queued up, they added to that time, they had to be pulled out, questions had to be asked of them, they had to fill up the forms, they had to be helped, they had to rejoin the queues," he said. "So, all these added up."

The minister added that travellers are now more aware of the need to fill up the necessary forms before arrival.

He noted that, pre-pandemic, ICA had the flexibility of moving passengers to different immigration lanes or parts of the airport when flights bunched up. Clearing immigration took about 40 to 45 minutes in such instances.

There are more constraints now, he said.

Currently, only Terminal 1 and Terminal 3 are opened. Terminal 2 and Terminal 4 have been closed since May last year, in part due to the low passenger numbers caused by the Covid-19 pandemic.

There are also measures in place at the airport to segregate arrivals from countries deemed to have higher risk of infections.

The additional requirements in the immigration process are also linked to a country's risk tolerance, he said.

Citing Singapore's requirement for VTL passengers to take a Covid-19 test upon arrival at the airport, he said this can take 20 to 30 minutes.

"There are other countries, other airports which don't do it. Heathrow, for example, does not do on-arrival testing, so of course the experience for the traveller is better. But you go home, you make an appointment.

"But, there is a difference in risk tolerance."

Mr Shanmugam said ICA officers have been taking the brunt of complaints from some travellers. He commended the officers for their hard work in various front-line roles.

"I spoke with some officers, told them to keep in good cheer, not to let some complaints affect them, do their work, and we will continue to look at processes to see how we can improve," he said.

Editorial note: The story has been updated for clarity.