The Championships are due to take place at the Tacen Whitewater Course from May 31 to June 4 but heavy rain at the end of April has caused a setback for organisers in Slovenia's capital.

"The water level during the last floods was really high and it flooded the majority of the venue," said Jakob Marušič, head of the Organising Committee.

"All the hard work we already invested into the venue is gone; we're now at the beginning.

"Approximately 50 metres³ of material has been washed away, so we will have to cart the new material to the venue again and harden everything.

"We haven't seen the bottom of the course yet, so we cannot estimate the extent of the damage because Sava River is not transparent enough at the moment."

Marušič has admitted that the damage will make the Championships more expensive than initially forecast, with the flooding washing away much of the work carried out over recent months.

Organisers remain confident the issues can be resolved, with just three weeks left to go until the Championships begin.

"There is significant damage on the river bank, both on the old part from the year 1990 as well as on the new part," Marušič said.

"This confirmed that the concrete which the construction company used last year was of bad quality.

"We will have to carry on negotiations with the construction company regarding the reclamation, and then repair the course.

"It seems we will not finish the construction works until the very last days before the Championships.

"Unfortunately the grass and green areas we are used to in Tacen will be missing in some parts of the venue.

"The nature really tricked us and made these Championships more expensive by tens of thousands of Euros."

The Championships are due to begin with an Opening Ceremony on May 31 in Ljubljana city centre, with competition taking place from June 1 to 4.