SCREENING FOR APPROPRIATE ASSESSMENT REPORT FOR LOUGHFUNSHINAGH INTERIM EMERGENCY FLOOD RELIEF WORKS - Lough Funshinagh, County Roscommon.
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SCREENING FOR APPROPRIATE ASSESSMENT REPORT FOR LOUGHFUNSHINAGH INTERIM EMERGENCY FLOOD RELIEF WORKS Lough Funshinagh, County Roscommon.
Screening for Appropriate Assessment Report
Lough Funshinagh IEFRW
Roscommon County Council
September 2021
22168-6011-A ii September
2021
Screening for Appropriate Assessment Report Lough Funshinagh IEFRW 22168-6011-A i September 2021
Screening for Appropriate Assessment Report
Lough Funshinagh IEFRW
Contents
1. Introduction ........................................................................................................................................................... 4
1.1 Purpose of Assessment ............................................................................................................................... 4
1.2 Legislative Context ....................................................................................................................................... 5
1.3 Stages of Appropriate Assessment ............................................................................................................. 5
2. Assessment Methodology ..................................................................................................................................... 6
2.1 Appropriate Assessment Guidance............................................................................................................. 6
2.2 Desk Study .................................................................................................................................................... 6
3. Screening for Appropriate Assessment ................................................................................................................ 7
3.1 Management of Natura 2000 Sites ............................................................................................................. 7
3.2 Description of Proposal ............................................................................................................................... 7
3.2.1 Site Location ............................................................................................................................................ 7
3.2.2 Brief Description of the Proposal ........................................................................................................... 8
3.2.3 Purpose of the Proposal........................................................................................................................ 11
3.2.4 Characteristics of the Project ............................................................................................................... 11
3.2.5 Description of the Site .......................................................................................................................... 19
3.2.5.1 General Site Description .............................................................................................................. 19
3.2.5.2 Geology ......................................................................................................................................... 19
3.2.5.3 Hydrology ..................................................................................................................................... 20
3.2.5.4 Hydrogeology of Lough Funshinagh............................................................................................ 24
3.2.5.5 Ecology.......................................................................................................................................... 25
3.2.5.6 Invasive Species ............................................................................................................................ 26
3.2.6 Identification of Other Projects or Plans or Activities ......................................................................... 28
3.2.6.1 Introduction.................................................................................................................................. 28
3.2.6.2 Plans .............................................................................................................................................. 28
3.2.6.3 Planning Applications ................................................................................................................... 28
3.2.6.4 EPA Licenced Activities and Urban Wastewater Treatment Plants ........................................... 29
3.2.6.5 Project Remediation Plan ............................................................................................................ 29
3.2.6.6 Climate Change ............................................................................................................................ 30
3.3 Identification of Natura 2000 Sites ........................................................................................................... 30
3.3.1 Zone of Impact Influence ...................................................................................................................... 30
3.3.2 Identification of Natura 2000 Sites ...................................................................................................... 30
3.3.3 Characteristics of Natura 2000 Sites .................................................................................................... 32
3.3.4 Conservation Objectives ....................................................................................................................... 35
3.4 Identification of Potential Impacts ........................................................................................................... 36
3.5 Assessment of Significance of Potential Impacts ..................................................................................... 36
3.5.1 Lough Funshinagh SAC .......................................................................................................................... 37
3.5.1.1 Construction Phase ...................................................................................................................... 37
3.5.1.2 Operational Phase ........................................................................................................................ 40
3.5.1.3 Summary....................................................................................................................................... 41
3.5.2 Lough Ree SAC ....................................................................................................................................... 42
3.5.2.1 Construction Phase ...................................................................................................................... 42
3.5.2.2 Operational Phase ........................................................................................................................ 43
3.5.2.3 Summary....................................................................................................................................... 47
3.5.3 Lough Ree SPA ....................................................................................................................................... 48
3.5.3.1 Construction Phase ...................................................................................................................... 48
3.5.3.2 Operation Phase........................................................................................................................... 49
3.5.3.3 Summary....................................................................................................................................... 49
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3.5.4 Lough Croan Turlough SAC, Four Roads Turlough SAC, Lisduff Turlough SAC, Ballinturly Turlough SAC,
and Fortwilliam Turlough SAC ............................................................................................................................. 49
3.5.5 Lough Croan Turlough SPA ................................................................................................................... 50
3.5.6 Four Roads Turlough SPA and River Suck Callows SPA ....................................................................... 51
3.5.7 Middle Shannon Callows SPA ............................................................................................................... 52
3.5.8 River Shannon Callows SAC .................................................................................................................. 52
3.5.9 Ballynamona Bog and Corkip Lough SAC, Castlesampson Esker SAC, Killeglan Grassland SAC, and
Crosswood Bog SAC ............................................................................................................................................. 53
3.5.10 Cumulative/In-combination Impacts.................................................................................................... 53
3.6 Conclusion of Screening Stage .................................................................................................................. 55
4. References ........................................................................................................................................................... 56
Tables
Table 1. Invasive flowering plant species recorded from hectads relevant to the project ...................................... 27
Table 2. Invasive aquatic species of fauna and fungus recorded from hectads relevant to the project ................ 27
Table 3. Planning permissions granted by Roscommon County Council in townlands of the outfall pipe route for
the period 2016 to 2021 .............................................................................................................................................. 28
Table 4. Summary of urban wastewater treatment plants within the Upper Shannon Catchment (26G) and Upper
Shannon Catchment (26E) ........................................................................................................................................... 29
Table 5. Designated conservation sites within 15 km of the IEFRW site .................................................................. 31
Table 6. Natura 2000 sites located within 15 km of the works site with Qualifying Interests (QIs) and Special
Conservation Interest (SCI) .......................................................................................................................................... 32
Table 7. Potential ecological impacts of the proposed Interim Emergency Flood Relief Works ............................. 36
Table 8. Historical Water Quality Status and Risk Scores for Lough Ree .................................................................. 47
Table 9. Comparison of Lough Ree and Lough Funshinage Water Quality ............................................................... 47
Figures
Figure 1: Location of the outfall pipe route at Lough Funshinagh in south County Roscommon ............................. 8
Figure 2: Overview of outfall pipe route from Lough Funshinagh, access routes and access points, and locations of
watercourses and Natura 2000 site ............................................................................................................................ 10
Figure 3. View of full extent of the IEFRW and nearby SAC’s and SPA...................................................................... 17
Figure 4. Extent of pipeline to be constructed overlain on aerial imagery ............................................................... 18
Figure 5. View of western extent of pipeline route and temporary pump location ................................................ 18
Figure 6. Lough Funshinagh and Lough Cup (Source: OSI Discovery series mapping) ............................................. 21
Figure 7. Catchments - Lough Funshinagh (blue) and Lough Cup (red) .................................................................... 22
Figure 8. Aerial photography and satellite imagery of Lough Funshinagh from differing years.............................. 24
Figure 9: Graph illustrating groundwater levels at Lough Funshinagh since 2016 (taken from GSI Groundwater
Level Data Viewer (gwlevel.ie)) ................................................................................................................................... 25
Figure 10: Location of cherry laurel (Prunus laurocerasus) recorded along the outfall pipe route ........................ 26
Figure 11: SACs and SPAs located within 15 km of the IEFRW site ........................................................................... 32
Figure 12. Hydrological catchment map of Lough Funshinagh and Lough Cup ....................................................... 39
Appendices
Appendix 1 – Stages of Appropriate Assessment
Appendix 2 – Tabulated pipeline details
Appendix 3 – Drawings of Works
22168-6011-A ii September 2021
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Approved
Project No. Doc. No. Rev. Date Prepared By Checked By Status
By
September
22168 6011 A ÚW, MK. GH, POD DRAFT
2021
22168 6011 B October 2021 MK POD POD Final
MWP, Engineering and Environmental Consultants
Address: Reen Point, Blennerville, Tralee, Co. Kerry, V92 X2TK
www.mwp.ie
22168-6011-A iii September 2021
Screening for Appropriate Assessment Report Lough Funshinagh IEFRW 1. Introduction 1.1 Purpose of Assessment Lough Funshinagh is designated as a turlough but is often referred to as a ‘disappearing lake’ rather than a true turlough because, while the water level can fluctuate by several metres each year, it seldom ever dries out completely (McCormack et al., 2018). Historically, the water levels of Lough Funshinagh have risen in the winter and receded during the summer. However, in recent years this has not occurred and there has been no return to the normal low level at the end of the summer. Instead, during the winter months, the water level of Lough Funshinagh has progressively risen and extended beyond its normal footprint, resulting in flooding events that have rendered the adjacent farmland inaccessible and cut off residents’ access to the local road network. The first major flood event since the 1940s occurred in the winter of 2015/2016 when the water level of the lake reached record levels, causing major flooding to the public road network and to three houses. Lough Cup, a turlough located one kilometre to the east of Lough Funshinagh, also reached an unprecedented level during the same period causing severe flooding of the adjacent road and cutting off direct access to three properties. Geological Survey Ireland (GSI) has been monitoring flood levels in Lough Funshinagh since 2016 (https://gwlevel.ie/). Between 2016 and 2020, a number of significant flood events have occurred. From 2016 onwards, three local secondary roads (L-2005, L20052 and L-7731) were raised to maintain community access. L- 2005 subsequently required additional raising, supported by the construction of a soil berm adjacent to dwellings. This sought to allow continuous over-pumping of water back into Lough Funshinagh. Water levels subsequently rose above floor level at three properties, requiring additional emergency pumping. By the end of 2020, one of these properties had been lost to flooding. In 2020 Roscommon County Council (RCC) undertook investigative measures to better understand the cause of the flooding. However, following a winter of heavy rainfall, the water level of Lough Funshinagh failed to recede from its 2020 peak. In fact, an April 2021 report by Geological Survey Ireland revealed that it had reached 69.04mOD, almost an entire metre above the previous record of 2016 (68.25m OD). This equates to approximately 4 million extra cubic metres of water. A risk evaluation was conducted by GSI based on the previous 80 years of data collected from Met Éireann. This found a 50% probability that water levels in the lake will not drop below 67.4mOD in 2021 and reach 68.4mOD in 2022. This is a 25-50 times greater risk of severe flooding than that which was estimated the previous year. If flooding of this nature occurs it will present an imminent risk to human health. It is likely that a further six properties will become flooded along with farmland. Consequently, in May 2021 RCC initiated emergency flood relief works with the sole purpose of preventing six homes having to be abandoned this winter due to flooding. The lowest floor level of these homes is 68.1m. These works were authorised under the statutory powers contained in the Local Government (Works) Act 1949 authorising RCC and its agents to enter on any land for the purpose of urgent relief works to mitigate damage. The works were to be carried out by the OPW and involved the installation of an approximately 3-kilometre-long outfall pipe travelling east towards Lough Ree from Lough Funshinagh to an outfall point on a stream just west of the N61 National Road, with the diverted waters eventually flowing to the River Shannon. Works to install the pipe commenced in early June 2021. On 9 August 2021, Friends of the Irish Environment (“FIE”) launched judicial review proceedings in the High Court against the decision of the Council. A temporary order halting work on the project was granted pending the substantive hearing. 22168-6011-A 4 September 2021
Screening for Appropriate Assessment Report Lough Funshinagh IEFRW The matter came before the High Court on 25 August 2021 at which time the Court heard RCC would consent to an order quashing its decision. RCC further consented to an order to undertake a Project Remediation Plan, this outlines the works and environmental management measures to be undertaken to restore the site and make good any areas disturbed by the construction works. To-date, 845.5m of the pipe has been installed, together with three manholes, the downstream outfall and some accommodation works. Following the conclusion of the court proceedings, RCC has re-examined the flooding situation to ascertain whether an interim solution could be undertaken to avoid the loss of nearby homes during the winter of 2021. RCC again engaged Malachy Walsh and Partners (MWP) to consider an interim solution which would alleviate the waters rising above 66m OD in the winter of 2021, with the consequence of saving a number of nearby homes. The proposal to carry out Interim Emergency Flood Relief Works (IEFRW) was developed, the details of which are outlined in further detail in Section 3.2 (Description of Proposal). This report, which contains information to enable RCC to perform its statutory function to undertake screening for AA in respect of the proposed IEFRW, was prepared by MWP. It provides information and appraises the potential, in view of best scientific knowledge, for the proposed IEFRW to have significant effects, either individually or in combination with other plans or projects, on any European sites. This screening for AA report has been undertaken by lead ecologist Monica Kane (BSc, MSc) and ecologist Úna Williams (BSc, MSc), both of Malachy Walsh and Partners Engineering and Environmental Consultants. 1.2 Legislative Context The Habitats Directive (92/43/EEC) seeks to conserve natural habitats and wild fauna and flora through the designation of Special Areas of Conservation (SACs), while the Birds Directive (79/409/EEC) seeks to protect bird species of special importance by the designation of Special Protected Areas (SPAs). It is the responsibility of each European Union member state to designate SPAs and SACs that form part of Natura 2000, a network of protected sites throughout the European Community. The Habitats and Birds Directives are transposed into Irish law through a number of legislative instruments, principally through Part XAB of the Planning and Development Acts 2000 to 2021 and the European Communities (Birds and Natural Habitats) Regulations 2011-2021. If, following the carrying out of an AA screening by RCC, RCC determines that significant effects on a European Site are likely or cannot be ruled out, an AA must be carried out. 1.3 Stages of Appropriate Assessment The AA process can comprise four-stages with issues and tests at each successive stage; the outcome of each determines whether a further stage in the process is necessary. The precautionary principle is required throughout, and each of the four stages are set out in Appendix 1. 22168-6011-A 5 September 2021
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2. Assessment Methodology
2.1 Appropriate Assessment Guidance
This screening for AA report has been undertaken in accordance with the European Commission Methodological
Guidance on the provision of Article 6(3) and 6(4) of the ‘Habitats’ Directive 92/43/EEC (EC, 2001) and the
European Commission Guidance ‘Managing Natura 2000 Sites’ (EC, 2019), and on guidance prepared by the
NPWS ‘Appropriate Assessment of Plans and Projects in Ireland: Guidance for Planning Authorities’ (DoEHLG,
2009). These guidelines stipulate that if there are any significant, potentially significant, or uncertain effects, an
AA must be carried out. If an AA is required in respect of any plan or project, that plan or project can only be
carried out if the AA concludes that the plan or project will not adversely affect the integrity of any European Site.
The task of the screening for AA is to establish whether a plan or project is likely to affect a Natura 2000 site (i.e.,
European site). This is based on a preliminary impact assessment using available information and data,
supplemented as necessary by local site information and ecological surveys (DoEHLG, 2009). This is followed by a
determination of whether there is a risk that the effects identified could be significant.
Once the potential impacts that may arise from the proposal are identified, the significance of these is assessed
using the following key indicators:
- Habitat loss
- Habitat alteration
- Water quality and resource
- Disturbance and/or displacement of species
- Habitat or species fragmentation
2.2 Desk Study
Considering the requirement that information on the existing environment be provided, a desk study was carried
out to collate available information about the permitted development site’s natural environment. These previous
reports were reviewed in addition to the following publications, data and datasets:
- Flood Analysis Report: Lough Funshinagh (MWP, 2021). Report ref. 19618-6001-B
- Ecological Review of Flood Protection Options: Lough Funshinagh and Lough Cup (MWP, 2020). Report ref.
19618-6002-A
- Ordnance Survey Ireland (OSI) aerial photography and 1:50000 mapping
- Available satellite imagery from Bing and Google Maps
- National Parks and Wildlife Service (NPWS) data, documentation and online mapping
- National Biodiversity Data Centre (NBDC) (online map-viewer)
- BirdWatch Ireland (online datasets)
- Teagasc soil area maps (NBDC website)
- Central Statistics Office – Census of Agriculture (online)
- Geological Survey Ireland (GSI) area maps and water level information
- Environmental Protection Agency (EPA) water quality data (online)
- Other information sources and research footnoted during the report
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3. Screening for Appropriate Assessment
Screening for AA (Stage 1) determines the need for a full Appropriate Assessment (Stage 2) and consists of several
steps, each of which is addressed in the following sections of this report:
3.1. Establish whether the construction and operation of the Interim Emergency Flood Relief Works (IEFRW)
is necessary for the management of a Natura 2000 site.
3.2. Description of the proposed project and the existing environment of the site.
3.3. Identification of Natura 2000 sites potentially affected.
3.4. Identification and description of potential individual and cumulative impacts of the proposed works.
3.5. Assessment of the significance of the impacts on the integrity of Natura 2000 sites.
3.6. Conclusion of screening stage.
3.1 Management of Natura 2000 Sites
The proposed Interim Emergency Flood Relief Works (IEFRW) is not connected with or necessary to the
conservation management of a Natura 2000 site. However, it is worth acknowledging that the persistent extreme
flooding since 2015/16 has considerably interfered with the typical hydrological regime of the lake and
consequently its ecological functions.
3.2 Description of Proposal
3.2.1 Site Location
Located in the centre of Ireland adjoining Lough Funshinagh, the Interim Emergency Flood Relief Works (IEFRW)
is approximately 10 km northwest of Athlone and approximately 65 km northeast of Galway City. The site of the
IEFRW is situated in south County Roscommon, approximately 6 km west-southwest of the County Longford
border and approximately 5 km west of the County Westmeath border. The large inland lake of Lough Ree is
positioned approximately 5 km east of Lough Funshinagh (see Figure 1, below) and approximately 2.02 km directly
east of the outfall pipe’s point of discharge. The pipe route is located within the 2-kilometre grid squares M94P
and M94U, within hectad M94.
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Figure 1: Location of the outfall pipe route at Lough Funshinagh in south County Roscommon
3.2.2 Brief Description of the Proposal
The IEFRW propose the installation of an approximately 3km long outfall pipe located east from Lough Funshinagh
to an outfall point at an existing stream. The discharge point to the stream is approximately 2km west of Lough
Ree and the stream flows into Lough Ree at Carnagh Bay. The aim of the scheme is to alleviate flooding in the
Lough Funshinagh area by a limited and defined lowering of the current high lake levels. This has been designed
to lower the lake by 540mm (where no inflows). The lake was at 67.8m OD on 6th Sept 2021, well above the normal
winter maximum level of 66.0m OD. The sole purpose of these emergency works is to prevent six homes having
to be abandoned this winter due to flooding. The lowest floor level of these homes is 68.1m.
The IEFRW works comprise of:
- a total length of outfall pipe 2,748.5m of which 1,457.5m comprises of 750mm diameter pipe and
1,291m of 600mm diameter pipe, 1,718.5m of which is in fields and 1,030m in road; and
- 18 manholes, 10 in the road and 8 in fields (refer to Figure 2 below).
The permanent solution will likely see the replacement of the temporary pumps at Lough Funshinagh with a
permanent intake structure and 146.5m length of underground pipe to M18. The permanent solution will be
subject to detailed design and will be subject to a separate planning application at a future date.
Works were commenced in early June 2021 and were suspended in early August 2021, following a court hearing.
To-date, 845.5m of pipe has been installed together with three manholes, the downstream outfall and some
temporary accommodation works (e.g. temporary compound, fencing, gates, hardstanding, etc.). A Project
Remediation Plan has been prepared and outlines works and environmental management measures to be
undertaken to restore the site and make good the areas that have been disturbed by the construction works. The
completion of the Project Remediation Plan is considered as part of the necessary in combination assessment,
and otherwise as part of the baseline environment.
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This report addresses the works required to complete the construction phase of the scheme, which will comprise
trench excavation and associated manhole construction through both fields and a local road. The remaining
IEFRW works will comprise of:
- a total length of outfall pipe 1,903m of which 1,290m of 750mm diameter pipe and 613m of 600mm
diameter pipe, 1,083m of which was in fields and 820m in road; and
- 15 manholes, 9 in the road and 6 in fields.
During the operational phase of the IEFRW, there will be 2 No. 300 mm diameter pumps (each with a 0.34m3/sec
capacity) that will be either diesel pumps or electric pumps with a diesel generator. The pumps will be placed
70m from the edge of Lough Funshinagh with the suction hoses running into the lake and delivering water from
the pumps to MH18. The hoses will be located on the ground adjacent but outside of the SAC boundary. Refer to
Figure 5.
22168-6011-A 9 September 2021Screening for Appropriate Assessment Report Lough Funshinagh IEFRW Figure 2: Overview of outfall pipe route from Lough Funshinagh, access routes and access points, and locations of watercourses and Natura 2000 site 22168-6011-A 10 September 2021
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3.2.3 Purpose of the Proposal
In recent years, as discussed in Section 1.1, above, water levels at Lough Funshinagh have failed to recede during
the summer months (at least to a level that provides capacity for influx of water during the winter season) and
instead have gradually risen during the successive winters leading to numerous flooding events. On 6th September
2021, the level of water at the lake measured 67.8 m OD1. This has put a further three houses in the area at
immediate risk of flooding as the lowest floor level of these homes is 68.1 m. As previously stated, the sole purpose
of these emergency works is to prevent six homes having to be abandoned this winter due to flooding.
3.2.4 Characteristics of the Project
The proposed construction works as part of the IEFRW, is described below and has been confirmed with the
project engineer. Scheme drawings are presented in Appendix 3 and below in Figures 3 to 5.
Interim Emergency Flood Relief Works (IEFRW)
Pipeline details:
Total length of outfall pipe installed to be 1,903m, made up of:
− 1,290m of 750mm diameter pipe (199m of concrete pipe; 1,091m of HDPE pipe)
− 613m of 600mm diameter pipe
The lengths of pipe in the fields and local road will be:
− Length of pipe in fields: 1,083m
− Length in of pipe at L7621 road: 820m
Size, scale, area, land-take Pipes are twin-walled HDPE apart for 199m of concrete pipe at the west end where the
cover depth is high.
Pipe invert depths are up to 3.40m in the road and 7.25m in fields. The depth of dig for
the pipes and Manholes between chainage 600m and 2,367m (excluding the 150m
already complete) varies from 2.0m to 4.5m.
Manhole details:
Construction of 15 No. manholes (9 No. in the road and 6 No. in fields). Manhole depth
to invert varies from 1.95m to 5.54m in the road, and from 3.05m to 6.02m in fields.
MH18 lies at distance of 160m from the lake edge.
Details of physical changes that
will take place during the Construction Phase
various stages of implementing
the proposal Excavation in open fields:
1 Ordnance Datum
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− The vegetated top-sod and topsoil will be stripped and temporarily stored for
reinstatement. Stockpiles of subsoil will be installed in a dry zone that is not
subject to flooding and away from land/road drains. No stockpiles will be in
place for more than 1 week. Excess soil will be immediately removed off site to
an authorised waste facility. Any rock that will be encountered will be reused in
the trench. A rock breaker may be required to break up rock in some areas.
Excess rock will be removed off site to an authorised waste facility.
− The trench is excavated down through the subsoil using an excavator machine.
Trenches will be excavated using trench boxes that allow vertical sides to the
excavation and therefore minimise the volume of excavated material. The
maximum depth that the trench box can support is 4.5m so the excavation has
to be benched back where the depth exceeds 4.5m. This will occur from
chainage 146.5m to 166.5m and from 264m to 600m. The depths here will range
from 4.5m to 6.0m.
− The trench is then prepared to receive stone bedding and surround for the pipe.
− The pipe is laid and appropriate imported stone material is placed over and then
filled back up to the top of trench. The trench is infilled with soil and reinstated
with topsoil followed by top-sod.
− At approximately 160m centres (12 no total) 450mm thick concrete stops are
placed around the pipe. These are to prevent groundwater using the stone
surround to the pipe as a drainage path and thus to protect the integrity of the
pipe.
− Where hedgerow or stonewalls are temporarily removed at field boundaries,
they will be reinstated. Prior to full removal of up to 144m (12m x 12 no.
hedgerow) of hedgerows at field boundaries, the hedgerow will first be dug up
below the roots, temporarily stored nearby and then reinstated immediately
upon completion of pipework. Therefore, the hedgerow will be returned no later
than 1 week after temporary removal.
Excavation in local road:
− Excavation in the local road will require excavation down through the existing
stone in the road using an excavator machine. As stone fill is removed, it is
temporarily stockpiled adjacent to the trench and removed from site and
brought to an appropriate licensed facility for disposal.
− The trench surface receives a temporary surface dressing of either spray and
chip or macadam. Once the overall scheme is completed, the pipe route and
associated road areas will receive a new permanent macadam finish as agreed
with RCC Roads Department.
Concrete breaks:
Concrete breaks will be constructed at approximately 160m intervals along the pipeline
route to ensure the integrity of the pipeline route.
Manholes:
− Manholes are concrete chambers that will be constructed at intervals along the
pipeline route where the direction or gradient of the pipe changes. It is proposed
to install 15No. pre-cast concrete manholes. The material excavated will be
removed from site and brought to a suitably licensed facility.
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− Prior to the manhole being installed a layer of compacted suitable stone will be
placed in the excavation to a level surface. The manholes are then positioned in
situ and backfilled around them with imported crushed stone material. The
precast manhole chamber cover is then put in place at a suitable level to allow
for a new road surface or reseeding.
Construction at land drains:
− Land drains will be blocked upslope of the crossing and a sump is formed using
sandbagging and stable clay soil material. This sump will accumulate water flow
in the drain (if it exists) and will facilitate the use of a 50mm or 100mm
submersible pump to over pump (fluming) the drain water across the excavation
and back into the drain on the down flow section below the excavation. Once
the sump and over-pumping mechanism is in place, then the trench excavation
will progress.
− Pipes will be placed under the drains and drain will then be reinstated. The over-
pumping measure can then be removed and normal drain flow resumes.
Construction time:
Once the trench is filled, the trenching and pipe laying process will move along the
fields in planned stages. It is estimated that 30m of pipe will be laid per day and thus
the works are estimated to take 12 weeks to complete.
Control of water in trenches:
Any inflows of water to the excavated trenches will be pumped into bunded areas
located adjacent to the excavations and then allowed to percolate back into the ground
so no water from the excavation will be discharged to water courses or drains during
the construction phase. Temporary bunded areas will be installed away from land or
road drains. These bunded areas will comprise of 25kg sand bags encircling a suitable
area of vegetated ground and will be temporary in nature, in situ for 2 weeks at most,
for the duration of the trench construction at a particular location. It is estimated that
up to 10no. will likely be required along the entire length.
Site Compounds:
Two no. site compounds occur on site at the following locations: in a field south of the
pipeline between MH16 and 17; and in a field south of the pipeline between MH07 and
MH08. The compounds will be used as a secure storage area for materials and also
contain temporary site units to provide welfare facilities for site personnel. Facilities
will include office space, meeting rooms, canteen area, a drying room and sanitary
provisions.
A bunded containment area is provided within the compounds for the storage of
lubricants, oils and site generators etc. Upon completion of the works the compounds
will be decommissioned by removal of the facilities and hard standing, backfilling the
area with the material arising during excavation, landscaping, topsoiling and seeding as
required.
As is standard at construction sites, a dry wheel wash will be provided at each
compound.
Standard construction practices for managing fuels and oils on site in relation to safe
storage, deliveries, dispensing, as well as vehicles and plant will apply.
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Construction traffic and haul routes:
The site will be accessed from the N61 and L7621. An alternative access point to the
site will be from the L2018, passing through Carrowloughan and turning North for
Lough Funshinagh.
Installation of temporary pumps:
During the operational phase of the pipeline, there will be 2 No. 300 mm diameter
pumps (each with a 0.34m3/sec capacity) that will be either diesel pumps or electric
pumps with a diesel generator located at MH18. The pumps will be placed 70m from
the edge of Lough Funshinagh with the suction hoses running into the lake and
delivering water from the pumps to MH18.
The 2 no. 300mm temporary suction hoses will not require excavation if the road is not
in use (it was shut for most of last winter 2020/2021) and will lay on the ground outside
and adjacent to Lough Funshinagh SAC. Refer to Figure 5. If the road is in use the hoses
be installed into a shallow trench in the road (0.45mD x 1mW x 8mL) and that covered
by a steel road plate. The trench will be dug into the stone of the already raised road
and thus not result in any exposed soil that may affect water quality. This work will be
completed in less than 1 day.
The 2 no. 300mm diameter suction hoses will run from the pumps 70m to the lake
edge. These are laid on the ground, with the final 20m suspended on floats within the
lake. An anchor will be required to hold the lake end of the hose in position (e.g. a
normal row boat anchor tied to the outer float). The pumps and hoses would arrive on
the back of a truck and offloaded via a hydraulic lifting arm on the back of the truck.
The hoses come in lengths that can be lifted by hand and clipped together. The area for
the pumps and generator if electric pumps are used would be bunded to contain an oil
or diesel spill.
Operation Phase
Once the IEFRW pipeline is constructed and the temporary pumps installed, it is
planned to pump out under 1.80 million m3 of water to lower the lake level by 540mm
(assuming no inflows during the period of the pumping). The maximum normal level of
the lake is 66.0m OD and thus the operation of the pipeline will not interfere with this
range. The water will be pumped from the lake via the temporary pumps to MH18.
Once in MH18 the flow is gravity. The pipe has a capacity of 0.6m3/sec so that is the
upper limit for the rate of pumping at that max rate, it would take 38.5 days to transfer
the 1.80 million m3. The volume will not be exceeded in any one calendar year. The
pumps will be rated so the actual volume pumped can be monitored.
This should lower the lake by 540mm (assuming no inflows). The lake was at 67.8m OD
on 6th Sept 2021, well above the normal winter maximum level of 66.0m OD. The sole
purpose of these emergency works is to prevent six homes having to be abandoned
this winter due to flooding. The lowest floor level of these homes is 68.1m.
There will be a wire mesh 'basket' around the pipe inflow to prevent fish, etc. getting
sucked up.
22168-6011-A 14 September 2021Screening for Appropriate Assessment Report
Lough Funshinagh IEFRW
The following equipment is required for the excavation of trenches and the laying of
the pipe:
− 199m of 750mm diameter concrete pipe
− 1,091m of 750mm diameter HDPE pipe
− 613m of 600mm diameter HDPE pipe
− 15 No. manholes (MH03 to MH16, and MH18)
− Wheeled / tracked excavators
− Dumper/swivel dumber
− Tractor trailer (low loader)
− Bobcat
− Ride on roller
− Road sweeper
− Pumps
− Bars and rope
− Concrete vibrator
− Drills
− Fencing
− Timber/plastic templates
Description of resource − Water pump
requirements for the
construction/operation and The following quantities of material will be required:
decommissioning of the − 199m of 750mm Diameter concrete pipe
proposal (water resources, − 1,091m of 750mm Diameter HDPE pipe
construction material, human − 613m of 600mm Diameter HDPE pipe
presence etc) − 41.5m of 1500mm Diameter Manholes 10 No. @ 4.15m average depth
− 13.4m of 1350mm Diameter Manholes 5 No.@ 2.68m average depth
− 1,766m3 of excess excavated material from field trenches
− 2,590m3 of excess excavated material from road trenches
− 1,086m3 of granular fill to trenches in fields
− 2,219m3 of granular fill to trenches in roads
− 14.8m3 of concrete breaks 12 No @ 1.233m3
Temporary water connections will be required at site compounds either via main supply
or water tanks.
It is envisaged that the development will have two crews of approximately 12 no. staff
per crew, in total 24 staff members during the peak of the construction works to include
site contractor(s), engineers, materials delivery personnel, environmental personnel,
health and safety personnel. Two crews will work concurrently on the remediation
works.
It is envisaged that the operation of the IEFRW will require 24 workers over a 12-week
period of time.
The construction of the pipe is anticipated to take 12 no. weeks or less to complete.
Description of timescale for the Working hours will be limited to 7:30am-5:30pm Monday to Friday and 7:30am to
various activities that will take 2:00pm on Saturdays. No work will be permitted on Sundays and Bank other than in
place as a result of exceptional circumstances.
implementation (including
likely start and finish date) The IEFRW is estimated to operate the equivalent of 38.5 days continuous pumping per
year for 2 years. However, the pumping may be intermittent. It will be replaced by the
permanent flood relief works, subject to that obtaining the necessary consents.
22168-6011-A 15 September 2021Screening for Appropriate Assessment Report
Lough Funshinagh IEFRW
For all trenching along the public road all excess excavated material will be immediately
taken off site in trucks and disposed of under license from RCC’s Waste Division or the
Environmental Protection Agency, as appropriate. This will prevent any contaminated
Description of wastes arising run-off to roadside drains where present during heavy rainfall.
and other residues (including
quantities) and their disposal During excavations in agricultural land/fields, excavated material will be stockpiled
adjacent to the section of trench, with appropriate material used as backfill.
Excess/unsuitable material will be immediately removed to an authorised waste
facility.
Contractors working on site during the construction works will be responsible for the
collection, control and disposal of all waste generated by the works. This waste may
Identification of wastes arising consist of hardcore, stone, concrete, ducting, shuttering timber, food waste from the
and other residues (including canteen and unused oil, diesel and building materials. This waste will be collected on a
quantities) that may be of weekly basis or depending on demand and taken off site to be reused, recycled and
particular concern in the disposed of in accordance with best practice procedures at an approved facility.
context of the Natura 2000 Domestic wastewater from the on-site holding tank will be collected on a weekly basis
network or depending on demand by approved contractors and disposed of in an authorised
facility in accordance with best practice. Plastic waste will be taken for recycling by an
approved contractor(s) and disposed or recycled at an approved facility.
Description of any additional
services required to implement
the project or plan, their
Traffic management will be required on the local road to ensure the safety of users.
location and means of
construction
22168-6011-A 16 September 2021Screening for Appropriate Assessment Report Lough Funshinagh IEFRW Figure 3. View of full extent of the IEFRW and nearby SAC’s and SPA 22168-6011-A 17 September 2021
Screening for Appropriate Assessment Report Lough Funshinagh IEFRW Figure 4. Extent of pipeline to be constructed overlain on aerial imagery Figure 5. View of western extent of pipeline route and temporary pump location 22168-6011-A 18 September 2021
Screening for Appropriate Assessment Report Lough Funshinagh IEFRW 3.2.5 Description of the Site 3.2.5.1 General Site Description The outfall pipe route lies within a flat, rural and agricultural area that is interspersed with single residential dwellings. The route traverses the townlands of Inchiroe and Gortfree, Lisfelim, Ardmullan, Srahauns, Carrownure, Bredagh, Carrick (part of) and Carrownderry in south County Roscommon and runs through the Electoral District (ED) area of Rockhill (CSO Area Code: ED30019). Central Statistics Office (CSO) data indicates that in 2016 this ED had a total population of 410 resident persons occupying single dwellings and farms as ribbon development, largely typical of rural areas such as this. Predominant industries within the Rockhill ED include agriculture, forestry, manufacturing and commerce2. According to the 2018 CORINE3 data series, land cover along the outfall pipe route is comprised entirely of ‘pastures’. There are small areas of ‘peat bogs’ and ‘inland marshes’ to the east of the N61 while to the northeast there is an area of ‘non-irrigated arable land’ adjacent to Lough Ree. West of Lough Funshinagh there is ‘natural grassland’, ‘land principally occupied by agriculture with significant areas of natural vegetation’ and ‘coniferous forests’, and, apart from a small patch of ’inland marshes’ adjoining the northwest corner, Lough Funshinagh is surrounded entirely by ‘pastures’4. 3.2.5.2 Geology Bedrock throughout the entire footprint of the pipe route, the surrounding areas and, indeed, most of County Roscommon, is a large band of ‘undifferentiated Visean limestone and calcareous shale’ of the ‘Dinantian Pure Bedded Limestones Formation’. A rocky outcrop is mapped west of MH18. The hydrogeology of Lough Funshinagh and its associated water level fluctuations is discussed in Section 3.2.5.4, below. A review of the online Teagasc map viewer determined that soil composition at the western end of the pipe route and around Lough Funshinagh comprises ‘fine loamy drift with limestones’ with ‘moderate drainage’ and within the Irish Soil Information System (SIS) Soil Series is classified as ‘Elton’. Soil at the eastern side of the pipe route is made up of ‘coarse loamy drift with limestones’ that drains ‘well’ and has an SIS Soil Series classification of ‘Mullabane’. Further east of the N61 at Lough Ree and in small pockets northwest of Lough Funshinagh, there are areas of poorly draining ‘peat’5. 2 Census 2016 Sapmap Area: Electoral Division Rockhill (cso.ie) [Accessed: 21st September 2021] 3 Co-ORdinated INformation on the Environment – data series initiated in 1985 by the European Commission to gather environmental data 4 GeoHive [Accessed: 22nd September 2021] 5 SIS Map (teagasc.ie) [Accessed: 21st September 2021] 22168-6011-A 19 September 2021
Screening for Appropriate Assessment Report Lough Funshinagh IEFRW 3.2.5.3 Hydrology Both Lough Funshinagh and approximately 470 m of the pipe’s route on the western side are located within the Water Framework Directive (WFD) catchment of ‘Upper Shannon 26G’ and the subcatchment of Shannon[Upper]_SC_100. The remaining eastern extent of the pipe route running towards Lough Ree is situated within the WFD catchment ‘Upper Shannon 26E’ and the subcatchment Shannon[Upper]_SC_090. Several 1st order streams feed into the western and northern sides of Lough Funshinagh but there are none to the eastern extent and consequently, the outfall pipe route does not interact with any waterbodies. The 1st Order Carrowphadeen Stream draining into Lough Ree is located approximately 2.4 km northeast of the pipe route while the 2nd Order Cross[Roscommon] River that eventually flows to Athlone Town is located approximately 2.8 km southwest of the pipe route. The entire route and surrounding area, including Lough Funshinagh and most of Lough Ree, is located within the WFD Ground Waterbody (GWB) of Funshinagh (IE_SH_G_091) where karstification is widespread, and permeability and transmissivity are very variable 6.Lough Funshinagh is fed by several local streams but there is no overland outflow. The streams are mainly to the north and west of the lake as can be seen on the Figure 6 below. Reduction in water levels is by infiltration into the underlying karst system and by evaporation. While infiltration through the lakebed is likely to be diffuse, there is at least one known submerged swallow hole at the southern extremity of the lake which is considered to be the main outlet. Upwelling from this source is not known to occur; consequently, Lough Funshinagh is a disappearing lake rather than a turlough in the strict sense of the definition. A turlough is a depression in limestone areas that is temporarily flooded by groundwater in most years. Turloughs are usually flooded in winter and dry during summer, though this varies greatly with rainfall and groundwater dynamics (NPWS, 2019). As Lough Funshinagh is predominantly surface water fed and groundwater drained, the lough essentially behaves more as a backed-up swallow hole than a typical groundwater fed turlough (McCormack et al., 2018). The surface catchment contributing to the inflow to the lake measures 37.80 km2 and the lake has a surface area of 3.80 km2 under normal conditions. 6 Summary of Initial Characterisation (dccae.gov.ie) [Accessed: 22nd September 2021] 22168-6011-A 20 September 2021
Screening for Appropriate Assessment Report Lough Funshinagh IEFRW Figure 6. Lough Funshinagh and Lough Cup (Source: OSI Discovery series mapping) The GSI in Parkes et al., (2012) have reported that the lake only drains fully occasionally, with the last rapid draining taking place in September 1996. They noted the likely presence of one or more swallow holes in the lakebed which are normally ‘plugged’ with an impermeable layer, such as clay and if the seal is broken, then the shallow lake may drain, leaving large expanses of dry lakebed. Gradual slumping inward of impermeable material may then reseal the swallow hole and allow the lake to fill gradually again. However, this is now not thought to be the case. There is no direct evidence of variation in the outflow rate from the lake and its apparent rapid draining is thought to be related to the low volume of water present. Water is draining at the same rate as when levels are high but when high the lake gives the appearance of draining very slowly (Sean Doyle, pers. comm.). The lake has been described as an intermittent turlough nearly drying out every 3 to 4 years and drying completely, except for a few pools, at longer intervals. The lake emptied in 1984 and 1996 (Drew and Burke, 1996). These authors described the basin as flat and shallow with a maximum depth of 2m. From 2005 OSI aerial photography, the lake bed appears almost if not completely dry (see Figure 8). A number of islands are found in the lake mainly in the eastern half including Inchiroe and Gortfree to the south, Inchihiceley, Inchnaderra, Inchmore and Inchinamona. These islands can become connected to neighbouring lands when the lake levels drop in summer. 22168-6011-A 21 September 2021
Screening for Appropriate Assessment Report Lough Funshinagh IEFRW Figure 7. Catchments - Lough Funshinagh (blue) and Lough Cup (red) Threats to the lake arise from drainage and agricultural intensification and the water quality effects that stem from this (NPWS, 2015). The following photographs are a mix of aerial photography and satellite imagery. They appear to have been taken in spring or summer– this assumption is based on tree foliage. In the summer of 2005 the lake appears to have emptied. 22168-6011-A 22 September 2021
Screening for Appropriate Assessment Report
Lough Funshinagh IEFRW
L. Funshinagh spring/summer 1995 (Source: OSI) L. Funshinagh summer 2000 (Source: OSI)
L. Funshinagh spring/summer 2005-2012 (Source:
L. Funshinagh summer 2005 (Source: OSI)
OSI)
22168-6011-A 23 September 2021Screening for Appropriate Assessment Report
Lough Funshinagh IEFRW
L. Funshinagh, likely spring 2016 (Source: Google
L. Funshinagh May 20127 (Source: Bing maps)
maps)
Figure 8. Aerial photography and satellite imagery of Lough Funshinagh from differing years
Lough Cup is a turlough and is located 1km southeast of Lough Funshinagh. It is considerably smaller in extent
and is also regarded as a turlough. Lough Cup has a catchment area of 1.60 km2 and an area of up to nine hectares
depending on water surface level and it can also disappear totally (Figure 7). It lies about 800m east of Lough
Funshinagh SAC and is not covered by this designation. It supports open water vegetation and fringing wetlands.
It is considered that there is connectivity between Lough Funshinagh and Lough Cup (MWP, 2019).
3.2.5.4 Hydrogeology of Lough Funshinagh
A typical turlough, of which there are many in County Roscommon, occurs where ‘glacially scoured basins fill with
groundwater in the winter and dry out in the summer as the water table lowers’ (Meehan, 2018). As discussed in
Section 1.1, above, Lough Funshinagh has been designated as a turlough (NPWS, 2015) due to the significant
water level fluctuations that occur when water levels rise during the winter and recede during the summer.
However, unlike a typical turlough, an extensive area of water persists most years at Lough Funshinagh, and it
dries out completely only approximately once every ten years. Furthermore, it is predominantly surface water fed
rather than groundwater fed as is typical of turloughs. For these reasons, Lough Funshinagh is often known as a
‘disappearing lake’ or an ‘intermittent turlough’ (NPWS, 2015) rather than a true turlough.
The lake is underlain by Carboniferous limestone and karstification is widespread within the GWB. As a result, the
reduction in water levels at Lough Funshinagh is by infiltration into the underlying karst system and via
evaporation. While infiltration of water is likely to be diffuse, there is a submerged swallow hole at the southern
extremity of the lake that is thought to be the main outlet. Upwelling from this source is not known to occur
meaning the lake essentially behaves more as a backed-up swallow hole rather than a typical groundwater fed
turlough (McCormack et al., 2018).
7 Dated from https://zoom.earth/#view=53.50711,-8.105419,14z
22168-6011-A 24 September 2021Screening for Appropriate Assessment Report Lough Funshinagh IEFRW Since 2016, groundwater levels at Lough Funshinagh have been continuously monitored by Geological Survey Ireland (GSI) and since recording began, there has been a clear trend of increasing water levels as illustrated in Figure 9, below. A record high of 69.027 m above sea level (ASL) was recorded at the lake on April 3 rd 2021, exceeding the previous record set in 2016 by approximately 0.8 m. Levels have slowly dropped since then and as of September 21st 2021, the level of water measured 67.678 m ASL. Data collected by GSI measuring the level of groundwater at Lough Funshinagh is uploaded daily and is available to view at: https://gwlevel.ie/. Figure 9: Graph illustrating groundwater levels at Lough Funshinagh since 2016 (taken from GSI Groundwater Level Data Viewer (gwlevel.ie)) 3.2.5.5 Ecology While it is not hydrologically considered to be a turlough given the absence of upwelling, the NPWS and previous ecological reports (Goodwillie and Fahy, 1974) have classified Lough Funshinagh as a turlough. The NPWS have designated the lough a Special Area of Conservation under the Habitats Directive for the presence of a turlough. Goodwillie and Fahy (1974) noted that the shallower parts of the lake and the shores that are temporarily flooded in winter have the typical turlough flora of terrestrial plants that assume peculiar growth forms because of their sporadic submergence. The report written in 1974 also noted that Lough Funshinagh never dries out completely. Open water is colonised by large stands of Common club-rush (Schoenoplectus lacustris), which grades into stands of sedges and Common reed at the main inflow. The shallower parts of the lake contain semiaquatic plants which are variably exposed in summer including a rush species, sedges and broad-leaved plants such as Water spearwort (Ranunculus flammula), Water mint (Mentha aquatica), among others. The lake is fringed by wet grassland, which in turn grades into pasture (NPWS, 2015). The lake is important for wintering wildfowl including Whooper Swan, Bewick’s Swan, Golden plover, Wigeon, Teal, Mallard, Shoveler, Pochard, Tufted duck, Coot, Lapwing and Curlew. In the summer, the site attracts a good diversity of breeding waterfowl including Shoveler, Gadwall and Pochard (NPWS, 2015). Lough Ree is the third largest lake in Ireland and is situated in an ice‐deepened depression in Carboniferous limestone on the River Shannon system between Lanesborough and Athlone. The site spans Counties Longford, Roscommon and Westmeath. It has a very long, indented shoreline and hence has many sheltered bays. Although the main habitat, by area, is the lake itself, interesting shoreline, terrestrial and semi‐aquatic habitats also occur (NPWS, 2019b). 22168-6011-A 25 September 2021
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