The Lower Shannon encompasses Lough Derg and the river corridor running south through Killaloe to Limerick, passing through the Ardnacrusha hydroelectric scheme. Lough Derg is the second largest lake in the Republic of Ireland and presents a significant open-water challenge. The exit from the lake is notably wide, requiring approximately a 5km crossing to avoid a lengthy paddle around the shoreline. Wind-driven whitecaps can develop in the centre of the lake even in moderate conditions, and paddlers should assess conditions carefully before committing to open-water crossings. The lake is narrower than Lough Ree to the north, which limits fetch somewhat, but it remains a demanding paddle in anything but calm weather.

Killaloe serves as a practical access and exit point on the Lower Shannon, and a disused canal enters the river near the town, offering a quieter side route through dense vegetation. Wildlife along this stretch includes kingfishers. Holy Island on Lough Derg holds the remains of a monastery founded by St. Colum around 520 AD and is among the most historically significant stops on the lower river.

South of Killaloe, the Ardnacrusha Dam is a major logistical consideration. The dam has a total drop of approximately 100 feet, managed through two locks — the first dropping roughly 60 feet and the second around 40 feet. Passage through the locks takes approximately one hour. Paddlers should contact the lock keeper in advance to arrange transit. The lock chamber can be windy, cold, and damp. Below the dam, it is approximately 5km to Limerick City.

The Shannon Paddlers club is based at O'Briens Bridge in County Clare, on a flat and sheltered section of the river, with Class 2/3 whitewater accessible within easy reach toward Limerick. The club runs trips from April to October and offers Level 1 and Level 2 kayak instruction for those new to the river.