Works are now under way on the River Dee Special Area of Conservation (SAC) to reverse the damage done by installing instream fisheries development features such as croys on the river. It is now understood that these features are damaging to rivers and the current works on the River Dee aim to restore natural river process and improve habitats for Atlantic salmon and Freshwater Pearl Mussel. It is time to start planning for the same on the Lower River Shannon SAC which has been highly modified with weirs and deflectors to the detriment of the ecological status of the river.
The modifications on the River Dee were modest compared to the damage perpetrated by the ESB on the Lower River Shannon in a misguided effort to compensate for the reduced post-Shannon scheme flows in the river
According to the press release (see link below) Colin Simpson, the Ghillie at Lower Blackhall and Kinneskie fishing beat in Banchory, was frustrated by the construction of the Banchory croys in 1995. He said that “All the large boulders which made up the river bed were dragged out of the river by a large digger and heaped up to create the croys, others were used to reinforce the banksides, and in the end the river had changed completely. The damage to the freshwater pearl mussels was devastating and the salmon fishing at the beat has never recovered, in fact the catches got worse.” The modifications on the River Dee were modest compared to the damage perpetrated by the ESB on the Lower River Shannon in a misguided effort to compensate for the reduced post-Shannon scheme flows in the river.
On the River Dee, all the boulders will now be re-distributed in the river bed from where they were taken to provide habitat and ‘lies’ for adult salmon. At Banchory, 15 croys will be broken up, and a further 9 croys will be removed from Sluie/Commonty with the additional benefit of allowing gravel salmon spawning beds to recover. Read the news reports for the River Dee at the links below.
- £3.5 million project to restore River Dee
- Aboyne Croys Removed to Restore the Dee
- Removing Banchory Croys on the River Dee
- River Dee In-stream Restoration, Banchory
Also see the ‘River Dee restoration scoping study‘. Also this presentation entitled ‘Improving freshwater pearl mussel habitat though restoration of natural processes‘. It is time to start planning for the same on the Old River Shannon which has been highly modified with weirs and deflectors to the detriment of the ecological status of the river. See our previous post on this subject here:-
Since the Shannon scheme, the “old” River Shannon receives a compensation flow of 10 cumecs (cubic meters per second). This is equivalent to only a 1 in 50 year drought flow on the river prior to the construction of Parteen Regulating Weir. This has had a significant morphological impact on this river corridor; both as a consequence of the reduction in flow and due to the instream physical modifications which have been used by the ESB in a misguided effort to compensate for the reduced post-Shannon scheme flows in the river. This has had significant consequences for both the ecology and amenity value of the river. Rather than enhancing the river’s ecology, the intrusive instream physical modifications on the Lower Shannon are working against the rivers natural fluvial geomorphological and ecological processes, increasing encroachment of vegetation, reducing the channel’s conveyance capacity, and preventing the water body from reaching good ecological status.
The ORSRG is campaigning for the provision of increased and variable flows in the Old River Shannon to be delivered within the context of a sustainable management plan for the river and SAC. We are also campaigning for the removal of many of the fisheries weirs and angling structures in the river, to facilitate the restoration of a physically more naturalised river corridor in the interests of complying with the requirements of the Water Framework and Habitats Directives.