An RNLI lifeboat was launched after an individual entered the water in Lough Derg, Co Tipperary, on Sunday morning.
Valentia Coast Guard requested Lough Derg RNLI lifeboat to launch to help a person who was reported in the water in Youghal Bay.
The volunteer lifeboat Jean Spier was launched at 11.30am on Sunday and arrived at the scene seven minutes later.
The Irish Coast Guard Search and helicopter Rescue 117 was also dispatched from its base in Waterford to assist.
As the lifeboat was launching, volunteers were told that the person had been recovered from the water and was now ashore at Garrykennedy Harbour.
Those on board the vessel from which the individual had entered the water immediately recovered them and provided first aid.
RNLI volunteers assessed the individual while awaiting the arrival of the ambulance personnel.
After being further assessed by ambulance crew, the individual, who had been wearing a lifejacket, was transported to hospital by ambulance.
Valentia Coast Guard stood down Rescue 117 helicopter, which had been in a holding position close by and ready to land.
The Lough Derg RNLI lifeboat left the scene shortly after 12pm.
Peter Kennedy, launching authority at Lough Derg RNLI, said: “Thankfully, the person who entered the water was wearing their lifejacket and was quickly recovered on board, where they received essential first aid care.”
“We remind everyone, if you find yourself unexpectedly in the water learn to Float to Live: tilt your head back with your ears submerged, relax and try to breathe normally, move your hands and legs to help you stay afloat.
“It’s OK if your legs sink, we all float differently. Once your breathing is under control, call for help or swim to safety.
“If you see someone else in trouble in the water, remember Phone, Float, Throw: dial 999 or 112, or use VHF radio Channel 16 and ask for the Coast Guard.
“Tell the struggling person to Float to Live, throw them something that floats, such as a life ring,” he added.