Roundstone and An Cheathrú Rua have been found to be discharging raw sewage this year.
It's because their public sewers were not connected to treatment plants.
Roundstone's treatment is not expected until 2029 while An Cheathrú Rua's expected treatment year is 2030
Those projects must go through various stages, such as securing planning permission, acquiring land and procuring contractors, before construction works can begin.
The report says there may be uncertainty around exact completion dates, as these depend on how quickly each stage is completed.
Meanwhile improvement measures are required at the 34 priority areas - including four in Galway - to prevent wastewater discharges from harming rivers, estuaries, lakes and coastal waters.
The first of those is Mountbellew, but infrastructural upgrades are due to start in 2025 or 2026.
The other three are Athenry, Ballymoe and Loughrea.
For those areas, Uisce Éireann plans to start infrastructural upgrades in 2029 or 2030 or has no clear timeline to deliver the corrective actions to prevent pollution
Elsewhere, Leenane has been noted as one of five priority areas to protect shellfish, and infrastructural upgrades are required to do so.
Natioanlly, the Environmental Protection Agency says immediate action is required to improve water quality in rivers, lakes and coasts.
Its new report finds wastewater is still being released from many areas without adequate treatment.
It says over half of licensed treatment plants don't always meet EPA standards, and around 10 percent of storm water overflows don't meet the national standards set to limit pollution.
