July 2013 has not only been an exceptional month for MulkearLIFE and our work with Inland Fisheries Ireland and Limerick County Council but also with our other key project partner, namely the Office of Public Works. In July the OPW commenced work on the removal of a major barrier to upstream passage on the Mulkear River, namely Ballyclogh weir. This project, which has been in the planning for over a year, is the largest single instream measure that MulkearLIFE has undertaken to date. It has involved the removal of a dysfunctional fish pass and significant section of the unused weir at Ballyclogh.
The provision of access is key to project implementation (Image: Ruairí Ó Conchúir)
The planning has included a comprehensive appropriate assessment screening report to assess any potential impact of the work. The work consists of an upgrade of the existing weir at Ballyclogh. It will include the replacement of the existing dysfunctional fish pass (on the eastern end of the weir) and the upgrading of fish passage facilities.
Image showing the retained section of the weir (near bank) (Image: Ruairí Ó Conchúir)
The removal of the main section of the weir is a recognised and approved mechanism to provide fish passage and the planned work will provide fish passage for a wide range of fish species and other aquatic species found in the Mulkear. The work was preceded by extensive sea lamprey monitoring work from mid May onwards and by observation monitoring work on site from early June. This included extensive snorkelling of the site in May and June. MulkearLIFE noted that the vast majority of sea lamprey passage had occurred by June 21st 2013, with the overwhelming majority having occurred in the first 10 days of June.
Extensive sea lamprey monitoring work conducted in June & July 2013 incl. snorkelling
The provision of fish passage at all milldams is a requirement of the Fisheries Acts 1959 – 2010. It stipulates that there should be passage for all fish species at all times. In addition, the meets the requirements of the Habitats Directives and associated national legislation in relation to providing appropriate access to the upstream section of the Mulkear River for all species of European Union interest in particular: all 3 lamprey species, adult Atlantic salmon which give rise to juvenile salmon, all of which are designated in Annex II of the Habitats Directives. The work will also greatly assist the passage of European Eel and its prime predator the European Otter (both protected species). Improving and maintaining the diversity of fish species is considered an important component of the Water Framework Directive as fish are considered one of the main indicators of water quality.
Skilled OPW operator removes dysfunctional fish pass (Image: Ruairí Ó Conchúir)
The existing remaining portion of Ballyclogh weir (western side) will not be removed. Rather in consultation with the relevant built heritage officials, conservation work has been undertaken to underpin the structure, by remediating the effects of scour and undercutting currently taking place. This work is ongoing and to date has been achieved through the filling-in of the deep pools immediately below the weir face (western side) so as to provide a scour barrier.
Bank protection work on removed section of weir (Image: Glen Wightman)
This conservation work work will also replace missing and loose rock and will address the ongoing problem of unauthorised fishing activity at this point. This work will not result in any material change in the character of the existing weir.
Rock breaker required for certain sections of weir (Image: Ruairí Ó Conchúir)
Once completed the work will provide fish passage, will address concerns regarding unauthorised illegal fishing activity and will ensure that the integrity of the built heritage of the site is retained. The work has the potential to transform the Mulkear River and open an additional 184km of habitat to Sea Lamprey and expedite the upstream migration of Atlantic Salmon.
Upgrading the heritage value of retained section of weir (Image: Ruairí Ó Conchúir)
Site works are ongoing and will continue into August 2013.
Works at Ballyclogh set to continue into August 2013 (Image: Ruairí Ó Conchúir)