Owners of boats moored on the River Shannon and its tributaries and the inland waterways are counting the costs of the recent icy conditions which have caused the sinking of a high number of vessels.

The Irish Times reports that the Inland Waterways Association of Ireland (IWAI) has advised all boatowners to check their boats after reports of sinkings across six counties.

Among the sunken vessels are a 35ft cruiser opposite the Landmark Hotel in Carrick-on-Shannon. The worst situation is reportedly in Shannon Harbour, with an unusually high number of boats sunk or partially submerged.

Sunken boats often require full refitting to replace damaged finishings and damaged electronics. But of greater concern is the potential environmental impact due to fuel or oil spills, or the leaking of antifreeze and other chemicals.

The IWAI has blamed poor 'winterisation' as a factor in the sharp increase in sinkings. 

Winterisation involves the closing of sea cocks to prevent water entering the intake pipes and potentially bursting them when it freezes, or leaking when it thaws.

"Owners need to check on their craft regularly or have a local do it," said IWAI president Paul Garland. "The lessons learned this winter must be taken seriously. Heaters may not be enough; all sea cocks have to be shut."

Click HERE for Afloat.ie's advice on protecting your boat in the thaw.