According to the Shannon Catchment-based Flood Risk Assessment and Management (CFRAM) Study Technical Assessment: River Shannon Level Operation Review [PDF: Office of Public Works v2_0 July 2012]
ESB collects and maintains records of rainfall, river and lake levels and flow data. Even though ESB has no responsibility to supply flood warnings under their regulations, it issues twice weekly lake level forecasts to all the relevant stakeholders since 2010.
Those stakeholders include Waterways Ireland.
As the levels of the lakes are of great interest to boat-owners and others, it would be really nice if either the ESB or Waterways Ireland were to publish those forecasts. WI wouldn’t need any elaborate new system: they could send them around as marine notices, and the cost would be minimal.
But perhaps the forecasts are already published somewhere? If, Gentle Reader, you know where they are, do please leave a Comment [preferably with a link] below.