Reliable sources have revealed police were called to the river last weekend following complaints from members of the public.
It is understood the three had travelled more than 20 miles to the river in separate vehicles.
Police had still to confirm whether any fines were issued following the incident when the Leader went to press yesterday lunchtime (Tuesday).
It comes as police in the Wolds Division warned they will ‘come down hard’ on blatant breaches of Covid regulations.
Eight individuals were fined a total of £1,600 at the weekend after officers discovered them partying and camping overnight in woodland in the south of the district.
During the incident, officers handed out five fixed penalty fines on Saturday evening - and three more on Sunday morning when they returned to Ostler’s Plantation on the outskirts of Woodhall.
The fine for a first Covid breach is usually £200 although it can be reduced to £100 - if paid within 14 days.
East Lindsey District Council leader Craig Leyland, who represents the area, described the offenders as ‘selfish idiots’.
Meanwhile, Coun Leyland revealed district council officers were working closely with police to crackdown on people camping overnight in coastal car parks - another direct breach of Covid regulations.
Coun Leyland said people were using camper vans and often travelling long distances, and added it was an ‘increasing’ problem.
He added: “People know what the rules are. Please, keep to them, stay as close to your home as possible - and don’t visit the coast.”
Coun Leyland also said the coast was proving to be a ‘hot bed’ for Covid conspiracies, with people posting offensive messages on social media and in graffiti on buildings.
Louth Town Council discussed a similar matter at Tuesday night’s council meeting (January 19), which took place after the Leader went to press, regarding a proposal to write to the police regarding the ‘Covid Lies’ graffiti that was painted on several walls and signs around the town at the end of last year.