Bodies may remain uncollected and children might miss exams due to gridlocked roads in the event of a no-deal Brexit, a council has warned.
In a damning report, Kent County Council warned about the effect on other key services.
It said refuse could blight the streets and food deliveries could be disrupted as the county copes with 10,000 lorries parked or stacked on its roads.
A government spokesman said it was providing support to local authorities.
The 17-page report – an update on no-deal contingency planning – laid bare the possible Brexit scenarios for the county, with “prolonged disruption” predicted to affect several vital services.
It could result in staff shortages in areas such as social care, as well as problems for people trying to get to hospital and disruption to the delivery of medicines, the council said.
The coroner service “could face difficulties with the transport of the deceased to post mortem or body storage facilities… and travel by pathologists to mortuary to conduct post mortems”.
It goes on to say: “Schools could be compromised if staff and pupils cannot effectively travel to exams.”
Talking about waste management, the report said: “District and borough collection services may be delayed and disrupted if there is significant traffic congestion, which could lead to a build up of waste awaiting collection.”
Changes in the border at the cross-Channel terminals are likely to cause traffic congestion, with Kent’s roads forecast to feel the brunt.
The council warned it could exceed that of the problems experienced in 2015, when almost 7,000 HGVs were contained on the M20 in Kent as part of Operation Stack.
Richard Burnett, chief executive of the the Road Haulage Association, said the customs process in the event of a no-deal was “alarming”.
He said: “If there’s a slowing of that… people won’t get the stuff when they want it because it won’t be there.
“That’s going to be catastrophic for us and the nation.”
A government spokesman said: “We have been working closely with Kent County Council – and all other local authorities – to make sure they have the support and resources they need to cope with Brexit in any scenario.
“That includes keeping the county’s vital road networks moving so that local people, businesses, schools, and visitors face as little disruption as possible.”