At least 7,000 migrants have managed to cross to the UK in small boats this year.
Wednesday 30th September marked the 100th separate day when people have arrived in small boats in 2020, according to analysis by the PA news agency.
Migrants crammed into unsafe dinghies have reached the UK from France on more than one in every three days, data shows.
Immigration officials say screening centres are sometimes being “overwhelmed” by the high numbers while staff remain conscious of the threat of Covid-19.
Meanwhile, charities continue to call on the Home Office to provide safe and legal routes for asylum seekers to put an end to the perilous Channel crossings.
In 2019, Home Secretary Priti Patel vowed to make such journeys an “infrequent phenomenon”, but UK law enforcement now believe the issue will be here for a while.
A handful of people were seen arriving in Dover on Wednesday as migrants attempt the crossing before the weather worsens in autumn and winter.
Wednesday marked the 100th separate day of 2020 where migrants have successfully crossed the Dover Strait to the UK in small boats, PA analysis shows.
This means that people are successfully making the dangerous crossing more than once every three days.
The number of migrants arriving each day is heavily weather-dependent, with fewer than 10 arrivals on some days and hundreds making it to Dover on others.
In September alone, nearly 2,000 migrants reached the UK, more than the figure for the entirety of 2019.
Immigration staff say the “sheer volume” of migrant crossings in 2020 is “unprecedented” and has presented significant challenges.
Lucy Moreton, of the Union for Borders, Immigration and Customs (ISU), said: “On occasion this has overwhelmed screening centres, meaning that migrants must be transported longer and longer distances to be identified.
“Social services have also been hard pressed, meaning migrants must remain with us for longer periods before being collected and re-housed.”
She raised concerns about the welfare of staff and the resources they are being given and called for more investment.
Ms Moreton said: “The ever-present threat of the virus worries everyone of course, but there is no PPE possible if you have someone in your arms trying to lift them from an unseaworthy vessel.
“Migrants often arrive soaked to the skin and contaminated with human waste, having sat in bilge water with vomit, urine, etc. Just seeing folk in such condition has an emotional toll as well.
“There have been reports of staff working 15-17 hours, largely because of the need to transport migrants to suitable identification or holding areas.
“You can’t ‘clock off’ when you have the welfare of others to consider, and concerns have been raised about the safety of staff, especially drivers, on such extended hours.”
Charities continue to call on the Home Office to provide safe and legal routes for migrants so they do not try the Channel route.
Bella Sankey, director of Detention Action, said: “Since the Home Secretary naively pledged to make this dangerous route ‘unviable’, her department has presided over an unprecedented rise in people risking it all to make it to safety in the UK.
“The Government’s closure of all safe and legal routes for refugees to reach the UK is driving this shift, and it will continue, regardless of the changing seasons, until safe and legal routes are created once more.
“Government’s staggering incompetence in managing this situation safely is matched only by its casual disregard for human life.”
Stephen Hale, chief executive of Refugee Action, said: “The Home Secretary told the House of Commons this week she is working on new safe routes for people fleeing war and persecution to seek safety in the UK.
“She could make this claim a reality overnight – by restarting the Government refugee resettlement programme, which has been paused since March.
“The Home Secretary has recognised that a lack of safe routes pushes people into the hands of smugglers and into flimsy and dangerous boats.
“Now she needs to do something about it. This is why it’s urgent that she restarts the resettlement flights and makes a long-term commitment to this and other safe and legal routes, a vital lifeline for thousands of refugees.”
Natalie Elphicke, MP for Dover and Deal, said: “More needs to be done to bring an end to illegal trafficking and illegal migration. All options must be on the table to close down the route itself.
“The French must stop boats leaving in the first place, boats should be returned to France instead of bringing them into Britain, and we should return people who come in through these illegal routes, no ifs or buts.”
Picture: Archive photo, dated 14th September 2020, shows a group of people thought to be migrants arriving in an inflatable boat at Kingsdown beach, near Dover, Kent, after crossing the English Channel. (Gareth Fuller/PA).