The event is planned for 1 July, starting in Newburn, Newcastle, and ending three-and-a-half hours later on the Quayside.
Publicised on Facebook as the River Tyne Booze Cruise, organisers say an estimated 3,000 revellers are expected to take part in the event.
They insist the idea is not a hoax, asserting it is based on “a tradition in Finland called Kaljakellunta” and posted a video reportedly showing scores of young Scandinavians taking part in the 2015 Finnish event.
Also known as “beer floating”, it is an annual festival during which people float down the River Vantaa in dinghies and rafts, around 16 miles from the Finnish capital Helsinki, in Uusimaa province.
Its popularity has grown since it was first staged in 1997, according to a website about the event which reportedly has no official organiser.
“Kaljakellunta has been criticised heavily for the mess it leaves behind every year, as the cleaning usually falls to the councils of Helsinki and Vantaa,” says the website.
“Last year the councils estimated that the cleaning bill was over €40,000 (£34,500) in total.
“However, since Kaljakellunta has no official organiser, it is practically impossible for authorities to ban the event,” it adds.
It would appear organisers of the Tyne event want to recreate the gathering in Newcastle.
Their Facebook post, shared almost 10,000 times, includes the message: “1 rule: Stay in your craft at all times to eliminate accidents.
“Armbands / life jackets highly recommended.”
It has attracted a lot of interest, with nearly 16,000 comments and users tagging friends in this section of the post, suggesting “this would be a laugh” and “we should do this”.
One Facebooker wrote: “Practice run for the Thames??”
Northumbria Police said they are concerned about safety and will be speaking to the organisers.
A force spokesman said: “The River Tyne is not a countryside stream.
“The current is strong, there is a lot of debris and a number of vessels use the waterway every single day.
“A rubber dinghy is not an appropriate vessel to be used on this river and if people were to fall overboard then they could find themselves in real danger.
“If those involved are then consuming a significant amount of alcohol then that causes further concerns that could lead to a significant incident.
“We understand people want to enjoy the summer and have fun but we have a duty to ensure the safety of the public and put appropriate measures in place.”