A river weir in which two men drowned on a canoeing trip is impassable, accident investigators found.
Experts reviewing the deaths of Philip Kelly, from Aherlow, Tipperary and Connie Smith, from Killashandra, Cavan on the Clodagh in north Waterford on April 7 last year found the route cannot be passed by boat.
The men drowned after getting stuck in a weir at Portlaw, which is too short for kayaks and canoes regardless how quick or heavy the flow of water is.
The Marine Casualty Investigation Board (MCIB) found the men, who were on a trip with Derek Elliott, of Knockaderry, Co Limerick, did not carry out a recce of the route beforehand.
However, they said the river conditions, severely swollen by heavy rain, were not necessarily the reason for the tragedy.
Mr Elliot ran from the weir to raise the alarm when the men got stuck but by the time he came back his friends had drowned.
The three experienced canoeists only decided to try to pass the weir after barking dogs forced them to change their minds about walking back to their car.
The MCIB recommended canoeists always walk the river bank along a route they wish to use before entering the water and also note the effect of rainfall.
The Irish Canoe Union said it would like to see all weirs similar to the Portlaw design identified in order to alert canoeists and kayakers on first-time river trips.
Waterford County Council said lifesaving gear and warning signs about the weir have been installed on the Clodagh. Officials said life buoys previously installed on the river were vandalised prior to the accident and were not replaced.
They also warned it is not possible to barricade the weir from canoeists as this would trap rubbish and debris washed downstream and potentially cause flooding.
The MCIB said the weir is impassable because a back flow of water is longer than half a kayak length.
Investigators said that in general a kayaker can only pass a weir if the back flow is less than half and added: "The design of this weir made it impassable regardless of the water flow over it."
The MCIB also called for exit ladders to be fitted in the weir and for all canoeists and kayakers to undertake basic survival training.
The report said that the three men had entered the Clodagh on the Curraghmore Estate in Whitestown and paddled downstream for about half an hour until they reached the weir at Portlaw.
Local knowledge would also have told the men that the river is never used for canoeing, investigators said.
There had been a large amount of rain in the area in the previous five days including 17mm the day before. The report said the Clodagh was swollen and flowing faster than any of the canoeists expected
The trip downstream began at 7.30pm and there were several minor incidents on the descent, the MCIB said.
The three men got out of the water above the weir to walk back to their car through the Tannery, a disused factory, because the conditions were so severe.
They changed their minds after hearing dogs barking on the riverbank. All three agreed that running the weir was a safer option than being challenged by the animals.
Mr Smith and Mr Kelly tried to pass the weir and after getting stuck they shouted to Mr Elliot to run for help.
Twelve hours after the tragedy a sit-on kayak used by one of the men was still trapped in the weir.