The woman entered the water at what is locally referred to as the Treaty Stone, near Thomond Bridge, around 3.20pm, Friday.
A major rescue operation took place involving Gardaí, a boat crew of three members attached to Limerick Marine Search and Rescue Service, as well as local fire service personnel.
According to a reliable eye-witness, Gardaí threw the woman a lifebuoy, before she was recovered from the water by a swift water rescue technician boat crew attached to Limerick City and County Fire and Rescue Service.
Another reliable source said the woman was transferred to St Michaels Boat Club slipway and handed over to HSE paramedics.
The woman was transferred by ambulance to University Hospital Limerick where her condition is believed to be stable.