The fish pass at Ardnacrusha of the Lower River Shannon lets very few salmon upstream, but for those salmon that find their way through the fish-lock and into the upper Shannon to spawn this is one-way journey. Unlike silver eels (the 70% to 80% that are are not caught and trucked around the dams) that can take their chances with the turbines all salmon kelts descending from the upper River Shannon die in front the of the intakes at Ardnacrusha. They die because there is no fish pass to allow them downstream, and no way for them to pass through.
All salmon kelts descending from the upper River Shannon die in front the of the intakes at Ardnacrusha, or in the fish pass at Parteen
There is also no way for these fish to pass downstream at Parteen Weir. Some salmon kelts enter the fish pass at this location – but die here as there is no way downstream for them (see Photos). The Shannon scheme is a one way journey for these fish.
Historically thousands of salmon kelts would die in front of the turbine intakes at Ardnacrusha each year because there is no way down. However, with the current low numbers of salmon passing upstream the resultant quantity of kelts trapped is also significantly lower. However, for a river that is currently so far below its conservation limit (<5%), it is clear that fish passage facilities urgently need to be reviewed.
No way down for kelts on the River Shannon
For further information please see this link:
Also please contact Inland Fisheries Ireland directly and complain about the fish passage issues on the Lower Shannon.
Old River Shannon Foundation 
What is being overlooked is the amount of salmon for the Lower Basin Castleconnel and the Mulkear River that enter the Arnacrusha Fish Pass during the Pre- Spawning season and then find themselves trapped in the Headrace. These fish will also travel upstream to the entrance of the Parteen Fish Pass at times find themselves trapped in the upper tiers of the as they attempt to return to their designated spawning habitats on the Killmastulla , Castleconnell and the Mulkear
My attempts to highlight this issue for the last twenty years has been ignored by so called experts. 4,000 salmon approx are poached out of the Tail Race each pre-spawning season having taken refuge there during the low water summer conditions on the Old Shannon System
All of this reminds me of the words of song “when will they ever learn”