The RNLI has advised lake users to ensure they check their navigational charts following separate incidents on Lough Derg on Sunday.
In the first call-out, a lone sailor was rescued after a privately-owned 30ft cruise boat ran aground near Gortmore Point on the north eastern part of the lake.
The Lough Derg RNLI lifeboat based at Dromineer was requested to respond. The woman was reported to be “distressed” so a rescue team was sent to assist her.
The lifeboat was able to manoeuvre the vessel off the rocks and into deeper water where volunteers checked to ensure it hadn’t been damaged.
Two RNLI volunteers were transferred to the casualty vessel and remained with the woman until they reached Dromineer safely.
Later, the lifeboat was called into action again after a another vessel got into difficulty on the lake.
The alarm was raised at around 6.00pm when a 20ft motor boat, with two people on board, ran aground in Youghal Bay on the south-eastern area of the lake.
On reaching the scene, two RNLI volunteers waded into the shallows and were able to manoeuvre the casualty vessel into safe water. The vessel had not suffered any damage and RNLI crew helped to tie it up alongside in a harbour close by.
Following both incidents, Deputy Launching Authority for Lough Derg RNLI Lifeboat Brendan O’Brien said: “Lake users are advised to study their charts to familiarise themselves with water depths off the navigation routes.”