Elatagh Riparian and Instream Works

The Elatagh site works are in an area 4.3 km long, along the Elatagh River, North of Cloghan.

The Elatagh

The project involved the installation of approximately 4.3km of riparian fencing, planting of native grasses and shrubs and several instream measures including; pinning of woody material, artificial pool creation, installation of rubble mats, gravel regrading and creation of artificial meander complexes. Troughs and solar powered pumps will also be installed to provide an offline water supply for livestock.  

The above described works were carried out between the co-ordinates 54.875056N -7.975384W (Irish Grid: 201629E 403019N) & 54.889283N -7.962506W (Irish Grid: 202455E 404603N). 

There are many different pressures in this area such as:

The Finn catchment is an area of high biodiversity and conservation value. The area is protected by a number of National and International designations that can be explored on this map.

The Elatagh 001 waterbody has been identified as an ‘Area for Action’ within the second cycle River Basin Management Plan for Ireland 2018-2021. These actions will be prioritised to achieve WFD objectives and will be directed towards pressures such as agriculture, urban waste water, domestic wastewater and forestry. 

Issues on Site

This area of the Elatagh River had an inadequately fenced riparian buffer zone and exhibited significant instream habitat uniformity along the 3.4km length. Much of the instream gravel was unsuitable for spawning due to compaction with silt and numerous areas of gravel suitable for spawning were “high and dry” and unavailable for salmonid spawning. Several areas also had significant stands of overhanging trees which effectively blocked all sunlight from the river.

Elatagh River Water Quality data

 

 


Data before Works

Loughs Agency Survey Locations-Elatagh. Click on the map to see surveys results.

Prior to the works this site was identified as requiring environmental improvement measures based on surveys undertaken in the prioritization elements of the CatchmentCARE project. The metrics surveyed included RHATS (River Hydromorphology Assessment Techniques), macroinvertebrates surveys, fish EQRs (Ecological Quality Ratios) and chemical exports. Every potential site was also walked over by the CatchmentCARE team in order to design bespoke remediation works for the site .

RHAT Survey

RHAT 2019 Results- Moderate.

The River Hydromorphological Assessment Technique (RHAT) is a survey developed by NIEA specifically for the Water Framework Directive (Murphy and Toland, 2012). Hydromorphology describes the physical habitat of a river constituted by the physical form (abiotic and biotic) and flow of the river. 

RHAT 2020 Results- Moderate.

RHAT is designed to be a holistic visual assessment and can be used to assess individual sites. This generates data for 8 relevant variables of habitat quality within 10 sub-sections of a 500m length of channel. Key elements include the flow, sediment type, channel and floodplain dimensions, topography and substratum, continuity and connectivity of a river. Anthropogenic features such as bank protection works, artificial barriers (weirs, dams) and modifications to processes are also included. It is assumed that natural systems support ecology better than modified systems. Hence the RHAT method classifies river hydromorphology based on a departure from naturalness. It assigns a morphological classification directly related to that of the WFD: High, Good, Moderate, Poor and Bad, based on semi-qualitative and quantitative criteria.

RHAT 2021 (Spring) Results- Moderate

 More detailed information can be found in the RHAT guidance handbook

 

Fish EQR

2020 Fish EQR- Moderate

Electric fishing is undertaken as the standard sampling strategy. A timed, 10-minute fishing protocol is used. In shallow water locations electofishing backpacks are used as a power source and a team of two or three persons undertake the fishing, wading in an upstream direction, one undertaking the fishing and one carrying a bucket to retain captured fish. All fish encountered during the 10-minute fishing period, including crayfish and larval lamprey, are collected and retained in a holding bucket of clean water. All fish are subsequently measured and held in a recovery bin of water from the sampling site until all data collection is completed. Fish are then returned into the sampling site on completion of the site survey.

Key elements of the data collection are (a) recording of all fish species encountered i.e. the fish community composition and (b) the length range of all fish within any species (Note: Loughs Agency record length range for salmonids only). 

Macroinvertebrates

2020 Results. Macros- May be at Risk

An agreement between the Loughs Agency and IFI was made to use the ‘Small Stream Risk Score’ method as a component of the overall EQR value for waterbodies on the Finn. These will be carried out by LA and DCC staff at the same sites that 10 minute electrofishing surveys take place, which are an additional component of the overall EQR scoring system. These data will be used to establish a baseline and will be monitored throughout the life of the project.

2021 Spring Results. Macros- Not at Risk

 Data collected on macroinvertebrate populations will be in a format which can be used to calculate Q-Value scores (which are the standard EPA scoring system) and ASPT & BMWP Scores (which are the standard scoring systems used in Northern Ireland). This will allow these data to be compared temporally to data collected by the LA and EPA at corresponding sites in the past, facilitating observation of a longer trend in data for the use of CatchmentCARE project objectives. 

Chemical Export


Remediation Works

Each work package carried out by the Loughs Agency within the Finn Catchment SAC has undergone a thorough Appropriate Assessment and has received approval from the National Parks and Wildlife Service (NPWS). The appropriate assessment for this package can be found bellow:


The Loughs Agency, as a partner of the CatchmentCARE Project, proposed to carry out stream bank improvement works and instream improvement works along both banks of the Elatagh River in the Finn River Catchment, Co. Donegal.

The Riparian work involved the installation of fencing, planting of clutches of native grasses and shrubs for a riparian buffer zone, installation of 1800mm unigates, stiles and installation of water troughs for livestock using solar powered water pumps to provide a source of drinking water in lieu of access to the river by livestock.

The instream works involved the installation of rubble mats, pinning of woody material, regrading of gravel, bush trimming, pool creation and installation of artificial meanders at several locations along the length of the river stretch. A small amount of wetland planting also took place in an area of approximately 145 m2.

These works were conducted between the co-ordinates 54.874872N -7.975052W (Irish Grid Ref: 201650E 402998N) & 54.887274N -7.956949W (Irish Grid Ref: 202811E 404379N).


Curlew conservation is an issue in this area and all of the remediation works have been advised and approved by the appropriate bodies before works have commenced. For example, to improve the riparian margin there will be more wetland vegetation planted to accommodate the Curlew Conservation Project. Please find a link for more information below.

A mix of Native grasses and shrubs will be planted within the buffer strip created between the fencing and the water’s edge. Planting of native broad leaf trees has been rejected due to the existence of nesting Curlew in the area which are being monitored by the Curlew Conservation Programme. Trees increase the risk of predation of Curlew nests and chicks as they can be used as roosting sites and observation posts by Corvids who predate on the Curlew young.


Soft engineering measures


Additional works

A follow up site visit in Early January 2022 highlighted an area of erosion along a meander within the centre of the habitat improvement works had been advancing. This was due to natural erosion which was not targeted within the initial works as the CatchmentCARE remit was to address anthropogenic processes impacting the riverine stretches.

However, for protection of the area of gravel regrading in areas below the erosion it was decided that there should be a second implementation of green engineering measures on these areas which included:

  • Reprofiling of the bank areas which were being undercut and eroded;
  • Installation of CoCoBN fibre on top of newly regraded soil
  • Introduction of woody material at the base
  • Installation of rock rolls at the toes of areas that are uniquely vulnerable to heavy erosive forces.
  • Installation of additional fencing to further prevent poaching from livestock.

These additional works will minimise the amount of sediment loads being introduced to the river and will help protect the integrity of the spawning gravels downstream.


Sheep Dips

The CatchmentCARE Team in partnership with Teagasc have created a best practice demonstration video for the correct procedures for dipping sheep and the disposal of spent sheep dip as well as an infographic leaflet on the correct disposal of spent sheep dip. 

CatchmentCARE & Teagasc Sheep Dip Demonstration

Info-graphic advising on the safe disposal of sheep dip can be found here:

Info-graphic on Good Agricultural Practice for the Protection of Waters can be found here:


Outcome based Results

The 2022- 2022 Redds survey carried out by the Loughs Agency has seen the benefits of the remediation work with having found several redds in areas with no previous spawning activity and in other areas the counts have went from 12 to 30 redds.

Example of the Redds found in the Elatagh

The team have been able to capture drone imagery of the Elatagh Habitat Improvement works and extremely pleased with the naturalisation of the implemented works to the local environment.

Elatagh River Drone Footage


Project Legacy

All restoration projects completed under the CatchmentCARE Project in the Finn Catchment have a built in legacy element. The sites will continue to be monitored by Loughs Agency using macroinvertebrate surveys and electrofishing so that any changes in the river fauna can be detected over time. There is a need to be mindful of seasonal changes and natural fluctuations in the rivers which can only be accurately ascertained with continuous monitoring. Many of the mitigations put in place by the CatchmentCARE Project could take years to really meet their full potential in terms of improving water quality. Legacy sampling regimes will help give a clearer understanding of how works undertaken by CatchmentCARE impact the rivers in the long term.

Contact CatchmentCARE

RHAT 2019 Results- Moderate.

RHAT 2020 Results- Moderate.

RHAT 2021 (Spring) Results- Moderate

2020 Fish EQR- Moderate

2020 Results. Macros- May be at Risk

2021 Spring Results. Macros- Not at Risk

Example of the Redds found in the Elatagh