Ryewater Arterial Drainage Scheme

Office of Public Works Arterial Drainage Maintenance Works - Ryewater Arterial Drainage Scheme

Natura Impact Statement 2016 to 2020

Office of Public Works Main Street Headford Co Galway Ireland

JBA Project Manager Tom Sampson 24 Grove Island Corbally Limerick Ireland Revision History

Revision Ref / Date Issued Amendments Issued to

Nathy Gilligan, OPW Draft Report / October 2015 Tony Brew, OPW Revised description of Nathy Gilligan, OPW Final Report / November 2015 proposed maintenance works Tony Brew, OPW Final report revised following Nathy Gilligan, OPW V6.0 /July 2016 Tufa Springs Surveys in 2016 Tony Brew, OPW Revisions following client Nathy Gilligan, OPW V7.0 / August 2016 review Tony Brew, OPW Change of report title and Nathy Gilligan, OPW V8.0 / August 2016 amendment to concluding text Tony Brew, OPW Contract This report describes work commissioned by the Office of Public Works, by a letter dated 05/06/2015. The Office of Public Works representative for the contract was Tony Brew. Laura Thomas, Tom Sampson and Anne Murray of JBA Consulting carried out this work.

Prepared by ...... Anne Murray BSc MCIEEM Senior Ecologist

Reviewed by ...... Declan Egan Environmental Director Purpose This document has been prepared as a Final Report for the OPW. JBA Consulting accepts no responsibility or liability for any use that is made of this document other than by the Client for the purposes for which it was originally commissioned and prepared. JBA Consulting has no liability regarding the use of this report except to the OPW. Copyright © JBA Consulting Engineers and Scientists Ltd 2016 Carbon Footprint A printed copy of the main text in this document will result in a carbon footprint of 140g if 100% post-consumer recycled paper is used and 140g if primary-source paper is used. These figures assume the report is printed in black and white on A4 paper and in duplex. JBA is aiming to reduce its per capita carbon emissions. 2015s2916 Ryewater Natura Impact Statement v8.0 i

Executive Summary JBA Consulting has been commissioned by the Office of Public Works (OPW) to provide environmental consultancy services in relation to statutory arterial drainage maintenance activities for the period 2016-2020. In 2014, following the methodology outlined in Ryan Hanley (2014a), a screening assessment was conducted to assess the likely significant effects on Natura 2000 sites of the proposed drainage maintenance activities in the Ryewater Arterial Drainage Scheme in accordance with Article 6(3) of the Habitats Directive (Council Directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora). Three source > pathway > receptor chains were examined to assess the likely impact of drainage maintenance activities on Natura 2000 sites; surface water, land and air, and groundwater pathways. From the screening exercise it was determined that significant likely effects may arise on the following Natura 2000 sites as a result of OPW drainage maintenance activities in the Ryewater Drainage Scheme.  Rye Water Valley/Carton SAC (001398) There is potential for the conservation interests of the Natura 2000 site to be impacted by all pathways, given that the habitats present are groundwater dependent and have connectivity to surface water, and that scheme watercourses fall within the site itself. As a result, it was necessary to produce a Natura Impact Statement (NIS) in support of a Stage 2 Appropriate Assessment to further examine the potential direct and indirect impacts of the proposed works on the integrity and interest features of the above Natura 2000 site, alone and in-combination with other plans and projects, taking into account the site's structure, function and conservation objectives. Further examination of the potential sources of impact on the Natura 2000 site above, looking at groundwater pathways, was conducted. Where potentially significant adverse impacts were identified, a range of mitigation and avoidance measures have been stipulated to help offset them. The Final version of the NIS concluded that more information was required on the location of the tufa springs in order to avoid these during the proposed works. As a result, a survey of the tufa springs was carried out by JBA to identify any springs, in order to avoid these. The survey has been incorporated into this NIS. The survey also identified springs which are not tufa forming but that should also be avoided to ensure that no impacts to groundwater occur.

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Contents

Executive Summary ...... ii 1 Introduction ...... 1 1.1 Background ...... 1 1.2 Legislative Context ...... 1 1.3 Appropriate Assessment Process ...... 1 1.4 Methodology ...... 3 2 Arterial Drainage Maintenance ...... 4 2.1 Background ...... 4 2.2 Drainage Maintenance Activities ...... 4 2.3 The Ryewater Arterial Drainage Scheme ...... 9 2.4 Drainage Maintenance Works Proposed for the Ryewater Arterial Drainage Scheme ...... 10 3 Screening Assessment Results ...... 15 3.1 Introduction ...... 15 3.2 Screening Assessment Conclusions ...... 16 4 Natura 2000 sites within the Zone of Influence of Drainage Maintenance Activities ...... 18 4.1 Introduction ...... 18 4.2 Rye Water Valley/Carton SAC (001398) ...... 18 5 Appropriate Assessment ...... 21 5.1 Introduction ...... 21 5.2 Tufa Springs Survey ...... 21 5.3 Impact Assessment ...... 21 5.4 Identification of Potential Sources of Impact ...... 21 5.5 Avoidance Measures ...... 24 5.6 Mitigation Measures ...... 24 6 Avoidance and Mitigation Measures ...... 31 6.1 Introduction ...... 31 7 Conclusions ...... 32 7.1 Future works between Sandsford Bridge to the Aquaduct at Louisa Bridge ...... 32 Appendices...... I A OPW Arterial Drainage Maintenance Service: Environmental Management Protocols and Standard Operating Procedures ...... I B Ecological walkover survey of Ryewater Valley/Carton SAC ...... I C Tufa Springs Survey ...... I

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List of Figures Figure 1-1: The Appropriate Assessment Process (from: Appropriate Assessment of Plans and Projects in Ireland - Guidance for Planning Authorities, DEHLG, 2009) ...... 2 Figure 2-1: Map of the Ryewater Arterial Drainage Scheme ...... 10 Figure 2-2: Kildare and Sandsford Bridge ...... 11 Figure 2-3: Sandsford Bridge to Aqueduct ...... 12 Figure 2-4: Aqueduct to Confey College ...... 13 Figure 2-5: Aqueduct to Distillery Road Retirement Home ...... 14 Figure 3-1: Channels with potential impacts via surface water pathways and the Rye Water Valley/Carton SAC ...... 15 Figure 3-2: Rye Water Valley/Carton SAC (red shading) extends from Carton House to Leixlip (NPWS, 2015) ...... 16 Figure 4-1: Tufa Springs Location ...... 19

List of Tables Table 2-1: OPW Drainage Maintenance Subcategories ...... 4 Table 2-2: OPW Drainage Maintenance Types ...... 4 Table 3-1: Screening Assessment Conclusions ...... 17 Table 4-1: Qualifying Interests of the Rye Water Valley/Carton SAC (001398) (NPWS, 2015) ...... 20 Table 5-1 Pathways of impact on the attributes of the designated features of the Ryewater/Carton SAC...... 21 Table 5-1: Impact Assessment ...... 27 Table 6-1: Specific Mitigation Measures ...... 31 Abbreviations DEHLG ...... Department of Environment, Heritage and Local Government EC ...... European Communities EDM ...... Environmental Drainage Maintenance EREP ...... Environmental River Enhancement Programme GWB ...... Groundwater Body GWD ...... Groundwater Dependent IFI ...... Inland Fisheries Ireland IROPI ...... Imperative Reason of Overriding Public Interest MAC ...... Maintenance Access Corridor NPWS ...... National Parks and Wildlife Service OPW ...... Office of Public Works SAC ...... Special Area of Conservation SOP ...... Standard Operating Procedure SPA ...... Special Protection Area 2015s2916 Ryewater Natura Impact Statement v8.0

1 Introduction

1.2 Legislative Context The Habitats Directive (Council Directive 92/43/EEC on the conservation of natural habitats and of wild fauna and flora) aims to maintain or restore the favourable conservation status of habitats and species of community interest across Europe. The requirements of Articles 6(3) and 6(4) of the Habitats Directive have been transposed into Irish legislation by means of the Habitats Regulations, 1997 (S.I. No. 94 of 1997) and the European Communities (Birds and Natural Habitats) Regulations 2011 (S.I. No. 477 / 2011). Under the Directive a network of sites of nature conservation importance have been identified by each Member State as containing specified habitats or species requiring to be maintained or returned to favourable conservation status. In Ireland the network consists of Special Areas of Conservation (SACs) and Special Protection Areas (SPAs), and also candidate sites, which form the Natura 2000 network. Article 6(3) of the Habitats Directive requires that, in relation to European designated sites (i.e. SACs and SPAs that form the Natura 2000 network), "any plan or project not directly connected with or necessary to the management of the site but likely to have a significant effect thereon, either individually or in combination with other plans or projects, shall be subject to appropriate assessment of its implications for the site in view of the site's conservation objectives". A competent authority (e.g. Local Authority) can only agree to a plan or project after having determined that it will not adversely affect the integrity of the site concerned. Under article 6(4) of the Directive, if adverse impacts are likely, and in the absence of alternative options, a plan or project must nevertheless proceed for imperative reasons of overriding public interest (IROPI), including social or economic reasons, a Member State is required to take all compensatory measures necessary to ensure the overall integrity of the Natura 2000 site. The European Commission have to be informed of any compensatory measures adopted, unless a priority habitat type or species is present and in which case an opinion from the European Commission is required beforehand (unless for human health or public safety reasons, or of benefit to the environment).

1.3 Appropriate Assessment Process Guidance on the Appropriate Assessment (AA) process was produced by the European Commission in 2002, which was subsequently developed into guidance specifically for Ireland by the Department of Environment, Heritage and Local Government (DEHLG) (2009). These guidance documents identify a staged approach to conducting an AA, as shown Figure 1-1.

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Stage 1 Stage 2 Stage 3 Stage 4

Screening for AA AA Alternative Solutions IROPI

Figure 1-1: The Appropriate Assessment Process (from: Appropriate Assessment of Plans and Projects in Ireland - Guidance for Planning Authorities, DEHLG, 2009)

1.3.1 Stage 1 - Screening for AA The initial, screening stage of the Appropriate Assessment is to determine: a. whether the proposed plan or project is directly connected with or necessary for the management of the European designated site for nature conservation b. if it is likely to have a significant adverse effect on the European designated site, either individually or in combination with other plans or projects For those sites where potential adverse impacts are identified, either alone or in combination with other plans or projects, further assessment is necessary to determine if the proposals will have an adverse impact on the integrity of a European designated site, in view of the sites conservation objectives (i.e. the process proceeds to Stage 2).

1.3.2 Stage 2 - AA This stage requires a more in-depth evaluation of the plan or project, and the potential direct and indirect impacts of them on the integrity and interest features of the European designated site(s), alone and in-combination with other plans and projects, taking into account the site's structure, function and conservation objectives. Where required, mitigation or avoidance measures will be suggested. The competent authority can only agree to the plan or project after having ascertained that it will not adversely affect the integrity of the site(s) concerned. If this cannot be determined, and where mitigation cannot be achieved, then alternative solutions will need to be considered (i.e. the process proceeds to Stage 3).

1.3.3 Stage 3 - Alternative Solutions Where adverse impacts on the integrity of Natura 2000 sites are identified, and mitigation cannot be satisfactorily implemented, alternative ways of achieving the objectives of the plan or project that avoid adverse impacts need to be considered. If none can be found, the process proceeds to Stage 4.

1.3.4 Stage 4 - IROPI Where adverse impacts of a plan or project on the integrity of Natura 2000 sites are identified and no alternative solutions exist, the plan will only be allowed to progress if imperative reasons of overriding public interest (IROPI) can be demonstrated. In this case compensatory measures will be required.

The process only proceeds through each of the four stages for certain plans or projects. For example, for a plan or project, not connected with management of a site, but where no likely significant impacts are identified, the process stops at stage 1. Throughout the process, the precautionary principle must be applied, so that any uncertainties do not result in adverse impacts on a site.

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1.4 Methodology This NIS has been prepared with regard to the following documents:  DoEHLG (2009 rev 2010) Appropriate Assessment of Plans and Projects in Ireland Guidance for Planning Authorities. Department of the Environment, Heritage and Local Government.  European Communities (EC) (2000) Managing Natura 2000 Sites: the provisions of Article 6 of the ‘Habitats’ Directive 92/43/EEC, Office for Official Publications of the European Communities, Luxembourg. European Commission.  EC (2002) Assessment of Plans and Projects Significantly Affecting Natura 2000 Sites: Methodological guidance on the provisions of Article 6(3) and (4) of the Habitats Directive 92/43/EEC, Office for Official Publications of the European Communities, Luxembourg. European Commission.  EC (2007) Guidance document on Article 6(4) of the 'Habitats Directive' 92/43/EEC – Clarification of the concepts of: alternative solutions, imperative reasons of overriding public interest, compensatory measures, overall coherence, opinion of the commission. European Commission.  EC (2007) Interpretation Manual of European Union Habitats. Version EUR 27. European Commission.  Fossitt, J., (2000). A Guide to Habitats in Ireland. The Heritage Council, Kilkenny.  National Parks and Wildlife Service (NPWS) (2008).The Status of EU Protected Habitats and Species in Ireland. National Parks and Wildlife Service, Department of the Environment, Heritage and Local Government, Dublin, Ireland.  NPWS (2014).The Status of EU Protected Habitats and Species in Ireland. Habitats Assessment Volume 2. National Parks and Wildlife Service, Department of the Environment, Heritage and Local Government, Dublin, Ireland.  NPWS (2014).The Status of EU Protected Habitats and Species in Ireland. Species Assessment Volume 3. Habitats Assessment Volume 2. National Parks and Wildlife Service, Department of the Environment, Heritage and Local Government, Dublin, Ireland.

1.4.1 Ecological Walkover Surveys Ecological walkover surveys have been conducted in relation to works on the Ryewater Arterial Drainage Scheme. The habitat maps and target notes for species are given in Appendix B. A specific tufa springs survey was also carried out and is given in Appendix C.

1.4.2 Consultation The findings of this assessment will be subject to consultation with the NPWS.

This report has been produced on currently available information, with the most up-to-date versions used. Where new, or updated, information becomes available the OPW will consider and review the findings of this assessment, if necessary.

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2 Arterial Drainage Maintenance

2.1 Background Between 1945 and 1995, under the Arterial Drainage Act (1945), the OPW completed 34 Arterial Drainage Schemes on river catchments, along with five estuarine embankment schemes (over 11,500km of channel and 730km of embankments). The OPW is statutorily obligated to maintain arterial drainage channels under the 1945 Arterial Drainage Act, and since their completion, maintenance of these Arterial Drainage Schemes has been ongoing, with the majority of channels maintained every five years. However, larger channels tend to be only maintained every ten years, on average.

2.2 Drainage Maintenance Activities Arterial Drainage Maintenance includes a range of operations such as silt and vegetation management, mowing and structure maintenance, as detailed in Table 2-1, and listed as channel, embankment or structure maintenance in Table 2-2 below. It is required to retain the arterial drainage scheme design capacity. Table 2-1: OPW Drainage Maintenance Subcategories Drainage Maintenance Subcategories

A Silt and vegetation management B Aquatic vegetation cutting C Bank protection D Bush cutting/Branch trimming E Tree cutting F Mulching G Mowing H Gate installation I Sluice maintenance J Bridge maintenance K Other

Table 2-2: OPW Drainage Maintenance Types Category Maintenance Type Code

Silt and vegetation management A Aquatic vegetation cutting B Bank protection C Channel Maintenance Bush cutting/Branch trimming D Tree cutting E Other K Bush cutting/Branch trimming D Tree cutting E Embankment Mulching F Maintenance Mowing G Gate installation H Sluice maintenance I Bridge maintenance J Structural Maintenance Bank protection C Bush cutting/Branch trimming D Tree cutting E

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The following sections, taken from Ryan Hanley (2014c) and OPW (2014), provide further details on the types and nature of arterial drainage maintenance operations undertaken by the OPW

2.2.1 Channel Maintenance Activities The majority of drainage maintenance activities are focused on channel maintenance. While the frequency of maintenance on an individual channel may vary, with some channels requiring maintenance annually and others only requiring maintenance every twenty years, the average channel requires maintenance every four to six years. In this regard, approximately 2,000km of channels are maintained annually and nearly all of the 11,500km of channels across Irelands Arterial Drainage Schemes will have been maintained at least once over a period of five years. Channel maintenance is organised on a regional basis, with OPW Arterial Drainage Maintenance Regional Offices in Limerick, Headford, Co. Galway and Trim, Co. Meath. Scheme Design Standards Arterial Drainage Schemes constructed under the Arterial Drainage Act, 1945 were designed to provide an outfall for drainage of agricultural lands, and generally provided protection for a 3-year flood event. Where the creation of an outfall dictated the design bed levels, greater protection than the 3-year flood event was achieved as a consequence. In the case of modern flood relief schemes, flood protection for a 100-year flood event would be the design objective. The original Scheme designs including the outfall datum for each of the Arterial Drainage Schemes are available in the relevant OPW Arterial Drainage Maintenance Regional Office. This includes the mapped Scheme design, and the associated long sections and cross sections. These designs are used to inform channel maintenance. Types of Channel Requiring Maintenance In the years following the construction of a drainage scheme there is a tendency for the channel capacity to be progressively reduced due mainly to the transportation and deposition of bed materials, the accumulation of silt and the growth of in-channel vegetation. The resultant channel maintenance consists of repetitive works of a cyclical nature, to restore the Schemes design levels i.e. outfall datum in order to maintain the channel's designed capacity to convey water. Channels are prioritised for maintenance based on the rate of deterioration and the risk arising. The selection takes account of requests from the general public and potential flooding risk to roads, properties, urban areas and sewage works (OPW, 2011a). Plane Bed to Low Gradient Channels Some 60 – 70% of maintained channels are of gentle longitudinal gradient and subject to relatively rapid deposition of silt, especially those that are subject to prolific growth of in-channel vegetation. The majority of maintenance works are therefore located on smaller lower-lying channels, with 90% of works in channels with a base width of <3m (OPW, 2011a). In such channels silt and in- channel vegetation may cause the low flow level to rise by 50-300mm above the Scheme design level. In such circumstances maintenance is focused on restoring both low-flow and flood-flow water levels to original Scheme design. Medium to High Gradient Channels A smaller proportion of channels are steep and fast flowing and are subject to flash floods, bank erosion and rapid movement of bed gravel. The steeper sections of channel normally require relatively little and infrequent maintenance works (OPW, 2011a) as opposed to channels of low gradient which are subject to rapid accumulation of silt and proliferation of vegetation. These channels will have a greater requirement for bank protection works. Periods and Cycles of Maintenance The average channel requires silt and vegetation management every four to six years. However, channels with prolific weed growth may require maintenance annually, particularly where downstream bridges are at risk of being blocked due to a flow of decaying vegetation in autumn. Conversely, some channels may only require in-stream maintenance every twenty years due to the self-cleaning characteristics e.g. high gradient channels.

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Where the period between previous channel maintenance works has been exceptionally long, dense scrub and woody vegetation can establish along the channel and within the maintenance access corridor. In such circumstances, drainage maintenance works will include the removal of scrub/transitional woodland (code WS1 in the Fossitt Classification, 2000) that has developed along the banksides via bush cutting/branch trimming, tree cutting or mulching. This is undertaken between the 1st September and 28th February to avoid the residential bird nesting season (from the 1st March to 31st August as per the Wildlife Act (1976). In contrast, in-stream works for silt and vegetation management are carried out outside of the salmonid spawning season (May to September) and the times that early life stages of salmonid fish will be present as per Section 173 of the Fisheries (Consolidation) Act (1959) on channels with salmonid spawning habitat. Any works required during this period are carried out in consultation with IFI. As a result there may be a two stage approach to the works, with silt and in-stream vegetation management carried out during the open season (i.e. summer months), while woody vegetation removal is carried out in the winter months. Other restrictions on works may also apply in relation to the presence/absence of other protected species such as White-clawed Crayfish and Sea, River and Brook Lamprey which will influence the timing of works.

2.2.2 Embankment Maintenance Activities A total of 5 No. Estuarine Embankment Schemes were constructed under the 1945 Act. In Addition a number of the Arterial Drainage Schemes have embanked sections, however, no embankments are present within the Ryewater Arterial Drainage Scheme. Scheme Design Standards As above for the Arterial Drainage Schemes, Estuarine Embankment Schemes constructed under the Arterial Drainage Act 1945 were designed to provide an outfall for drainage of agricultural lands, and generally provided protection for a 3-year flood event. Where the creation of an outfall dictated the design bed levels, greater protection than the 3-year flood event was achieved as a consequence. In the case of modern flood relief schemes, flood protection for a 100-year flood event would be the design objective. The original Scheme designs are available in the relevant OPW Arterial Drainage Maintenance Regional Office. This includes the mapped Scheme design, and the associated long sections and cross sections. Types of Embankments Requiring Maintenance All embankments and associated sluice structures (see section 2.2.3) are inspected annually for signs of disrepair. Regular inspections are carried out on sections of embankments, which are known from experience to be at risk, together with additional inspections after a storm surge at sea or a high tidal/flood event. Maintenance of embankments includes removal of vegetation to allow for inspection of the embankment, and in some cases the replacement of existing fencing with gates to allow for future access during maintenance.

2.2.3 Structural Maintenance Activities Structural Design Standards During the construction of the Arterial Drainage Schemes under the 1945 Act, some 18,500 No. accommodation bridges were identified and modified, or replaced as required. These bridges provide farmers owning land on both sides of a channels with farm vehicular and/or foot access from one side to the other. The type of bridge provided depended on the width, depth and required flow capacity of the channel, and ranged from concrete piped culverts to relatively large structures formed on concrete or masonry abutments spanned by structural steel beams, or lattice girders together with concrete or timber decking.

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During the Estuarine Embankment Schemes under the 1945 Act, existing sluice structures were identified and modified, or replaced as required. Additional sluice structures were constructed as required bringing the total number to approximately 750. The function of these sluice structures is to allow water from the floodplain behind the embankments to discharge to the main river or estuary. Types of Structures Requiring Maintenance In general, as channel maintenance proceeds, the bridges are examined by the supervisory industrial staff and if required, repairs/replacements are scheduled. The type of bridge structures, which are most likely to have fallen into a critical state of disrepair, are those with timber decking supported on steel beams, and those in which abutment foundations are being undercut. There is a standard type of design for the replacement of these structures, which consists essentially of mass concrete abutments with reinforced cast in-situ decking. This type of structure is simple to construct and under normal circumstances, it will last for many years with little or no maintenance. On many occasions, it is not necessary to totally replace a bridge, and repairs such as underpinning the foundation or replacement of wing-walls, parapets or sections of the deck may be all that is required to extend the useful life of the structure. All embankments and associated structures are inspected annually for disrepair. Due to the time elapsed since scheme completion, some of these sluice structures have reached their design life and have started to fail. In this instance, full replacement is required. Typically, this involves the installation of pre-cast headwalls and back walls, and the replacement of existing corrugated galvanised steel pipes with PVC plastic pipes. Sluice doors are the most frequent part of the sluice structure that are required to be repaired or replaced. Repairs to a sluice door consist of replacing the arms/hinges on the existing cast iron door. On occasion, the existing cast iron door would be replaced with a high-density polyethylene (HDPE) door. Blockages often occur at the doors of the sluices due to silt build up. These blockages are removed using along reach excavator working from the bank of the channel.

2.2.4 Plant and Machinery The types of machinery typically utilised during maintenance works would include 3600 hydraulic excavators (from 15-20 tonne excavators), mini-diggers, tractors and trailers, tipper lorries, hydraulic shears, hydraulic secateurs, chainsaws, mulchers and mowers; the machinery used is dependent on the maintenance activity being conducted. The removal of dense in-stream silt and vegetation requires the use of a hydraulic excavator with a 1.5m wide (approximate) bucket (capacity approximate 500ltrs). For standard excavators, works progress at a rate of 700m to 900m per week. In relation to long-reach excavators, works progress at a slower rate of between 200m and 350m per week. Rates may change due to channel width or ground conditions.

2.2.5 Maintenance Access Corridors (MAC) and Working Zone Maintenance sites are generally accessed via the public road and through farmland. A maintenance access corridor is utilised along one side of a channel for maintenance purposes. These established routes are used to track the hydraulic excavators for maintenance and for the disposal of spoil (see section 2.2.7). The same route is generally followed every maintenance cycle. This approach avoids disturbance of habitats on the opposite bank during works. Where grasslands are present within the maintenance access corridor, the impact is predominantly temporary as the grasslands are trampled by machinery and can recolonise following completion of the maintenance activities. Within woodland and scrub habitats a linear path more typical of disturbed vegetation i.e. scrub/transitional woodland (WS1) will be evident along the maintenance access corridor due to regular machine access. In this regard, the disturbance regime associated with the tracking of plant machinery along the maintenance access corridors on the channel bank arrests succession to mature woodland such that scrub/transitional woodland (WS1) dominates. Where mature trees are present these are generally avoided by plant machinery.

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Structures are generally accessed through farmland from the public road above. Plant machinery will utilise the same maintenance access corridor used for channel maintenance to gain access to the structure. Where individual trees, woodland and scrub habitats are present at the location of the structure, these may be removed to facilitate bridge inspection and works. Where mature trees are present these are generally avoided by plant machinery. The location of drainage maintenance works is generally accessed via public roads and through farmland, with the siting of mobile short-term staff welfare facilities, plant storage and car parking agreed with local landowners. There is no requirement for temporary site lighting. There is a requirement for water supply and disposal of wastewater from the welfare facilities (see section 2.2.7 in relation to waste disposal).

2.2.6 Site Compounds (Welfare Facilities), Access Routes and Haul Roads Haul roads are generally not required to facilitate drainage maintenance activities. Where access is required in soft ground conditions, plant equipment will be brought in on tracks or temporary matting will be laid to provide a corridor for machinery access. Where matting is utilised it will be completely removed post completion of works to allow vegetation to recolonise. All plant and machinery is confined to one defined access route to minimise disturbance. All plant and machinery are regularly maintained and serviced to minimise release of hydrocarbons. All hydraulic excavators and other plant machinery use long life engine oil and biodegradable hydraulic oil. Fuelling and lubrication are conducted a minimum of 50m away from all channels. Spill kits are present in all plant used in maintenance activities. Integrated submersible pumps are also deployed in the event of structural maintenance and the requirement for dewatering of excavations.

2.2.7 Waste Output/Disposal The material removed from a channel during silt and vegetation management is normally spread thinly along the bank or on top of existing spoil heaps where present within the access corridor. All dead wood material is left on site to decompose or is removed off site and utilised as firewood under local landowner agreements. Where mulchers or mowers are deployed, the arisings are left on site to decompose or the mulched material is buried. Construction and demolition waste from structures includes broken concrete and stone. Steel railings are returned to the depot for recycling. Used engine oil and hydraulic oil is disposed of by a licensed waste handler. Toilet facilities are maintained by a licensed waste handler. Any waste generated on site is returned to the depot for segregation and disposal by a licensed waste handler.

2.2.8 Working Hours All maintenance activities are undertaken during daylight hours. Standard working hours are 8.00am to 4.30pm, with lunch and tea breaks, Monday to Friday. There is no requirement for temporary site lighting to facilitate works. Machines are powered down when not in use.

2.2.9 Environmental Training Environmental training of all staff involved in drainage maintenance is an ongoing process. Technical and Operational Staff have completed formal training in Environmental Drainage Maintenance (EDM) in 2004. This training course was revised and expanded under the OPW’s Environmental River Enhancement Programme (EREP) and was delivered to all staff in 2010. The training programme delivered included presentations in river corridor ecology, the Environmental Drainage Maintenance Guidance Notes (Ten Steps to Environmentally Friendly Maintenance), maintenance strategies involving both ‘enhanced maintenance’ and ‘capital enhancement’, and OPW’s Environmental Management Protocols and Standard Operating Procedures (SOPs) (see section 2.2.11 for more details). Both sets of training were developed and delivered by IFI. The formal approach to EDM Training is complimented with on-site training. Regular site visits from IFI and OPW’s Environment Section provide further guidance and advice to operational staff. Auditing of operational staff on the implementation of the Environmental Drainage Maintenance Guidance Notes (Ten Steps to Environmentally Friendly Maintenance) is also carried out by both IFI and OPW’s Environment Section.

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In addition, other environmental training takes place as deemed beneficial, e.g. in 2008, the majority of the technical and operational staff were trained in Otter Awareness. This course, provided by the Department of Zoology, Trinity College Dublin, included presentations on Otter ecology, and on-site identification of Otter signs and suitable habitat.

2.2.10 Environmental Audits A portion of operational crews are audited annually by the OPW Environment Section and IFI for the implementation of the Environmental Drainage Maintenance Guidance Notes (Ten Steps to Environmentally Friendly Maintenance) and the OPW’s Environmental Management Protocol and SOPs. Auditing is carried out separately by both IFI and OPW Environment Section on a rotational basis to ensure all operational crews are audited at least once every three years. All audit results are forwarded to the relevant Engineer for that Scheme within two working weeks. In the event of an audit showing elements of unreasonable non-compliance with procedures, the relevant Engineer will be notified within one working day. Audit results are also forwarded to OPW Systems Manager for inclusion in monthly regional benchmarking reports.

2.2.11 Environmental Management Protocol and Standard Operating Procedures (SOPs) The OPW’s Environmental Management Protocols set out how regional management staff manage a range of environmental aspects, including programming of works to accommodate certain environmental windows or restrictions on timing of works, and recording of data. A total of 7 No. Standard Operating Procedures (SOPs) are applied during operational works. These SOPs set out actions designed to eliminate, or substantially reduce likely impacts to identified species and their associated habitats. These include:  Environmental Drainage Maintenance Guidance Notes (10 Steps to Environmentally Friendly Maintenance)  Lamprey SOP  Crayfish SOP  Otter SOP  Mussel SOP  Invasive Species SOP  Zebra Mussel SOP Appendix A contains the OPWs Environmental Management Protocols and Standard Operating Procedures (OPW, 2011b). This document can also be downloaded from http://www.opw.ie/en/media/OPW%20Environmental%20Management%20Protocols%20&%20S OPs%20April%202011.pdf.

2.3 The Ryewater Arterial Drainage Scheme The Ryewater Arterial Drainage Scheme is located in County Kildare. It includes 32km of watercourse and no embankments, 9km of which flow through the SAC. The watercourse is the Ryewater and it discharges into the River Liffey at Leixlip, downstream of the Louisa Bridge.

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Figure 2-1: Map of the Ryewater Arterial Drainage Scheme

2.4 Drainage Maintenance Works Proposed for the Ryewater Arterial Drainage Scheme Within the Ryewater Arterial Drainage Scheme the exact location and type of required maintenance activity varies over time. The screening assessment (JBA Consulting, 2015) was conducted on the assumption that all channels will be maintained during the 5-year period 2015- 2019. However, this NIS is based on more detailed information provided on the timing, frequency and nature of maintenance operations to be conducted on each channel and embankment. During the period 2016 to 2020 the maintenance activities proposed for the watercourses in the Ryewater Arterial Drainage Scheme, are:  A - Silt and vegetation management  C - Bank Protection  D - Bush cutting/branch trimming  E - Tree cutting  F - Mulching Aquatic vegetation cutting (activity B) is not currently proposed for watercourses in the Ryewater scheme in the period 2016-2020. Some instream works are anticipated downstream of the Aqueduct at Leixlip. It is currently not known where structural maintenance operations are proposed, and therefore it will be assumed that potentially these activities could occur on all structures within the scheme area during the period 2016 to 2020. A description of the proposed works has been provided by the OPW and these are given below.

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2.4.1 Proposed Work Details The Ryewater is not a confirmed arterial drainage scheme and no works have ever been carried out between Kildare and Sandsford Bridge previously.

2.4.1.1 Section 1 Between Kildare and Sandsford Bridge This reach of river is primarily a lake controlled by weirs, with reduced drainage outfall and no history of flooding, where maintenance is carried out by Carton House. A tree requires removal at Ham Island, however the house maintenance supervisor will be informed. No works required here by the OPW. Figure 2-2: Kildare and Sandsford Bridge

2.4.1.2 Section 2 Sandsford Bridge to Aquaduct

Given the sensitivity of this stretch of river, in relation to groundwater and surface water and the presence of springs including tufa springs, the proposed works have been altered to avoid impacts on the SAC. A site walkover was carried out by JBA ecologist Anne Murray with OPW staff to understand what works were required. Overall it is important to note that this stretch of river appears to be self cleaning and contains good gravels and low levels of instream vegetation. Therefore, very little maintenance is required here over the next few years. Some silt removal may be needed on a small stretch just south of the Sandyford Bridge, however that will not occur in this round of works, until a full an access track has been decided upon in terms of feasibility and this will undergo a full ecological and appropriate assessment, if proposed in the future. Following examination of the stretch of river, it was concluded that only certain works were needed as follows; Removal of a willow tree growing into the river from the bankside just immediately upstream of the aquaduct on the southern side of the river. This bank is directly connected to the groundwater discharges here and close to the wetland and marsh as shown in Figure 2-3. Removal of a tree at the entre arch of Sandyford bridge may also be required.

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Figure 2-3: Sandsford Bridge to Aqueduct

Tree at bridge arch in river – no machinery permitted. Access from southern bank. Tree on bankside growing into river to be removed by manual work only – no machinery permitted. Access from northern bank only. No access through SAC and tufa springs on southern side.

2.4.1.3 Section 3 Aqueduct to Confey College From the aqueduct to the Confey College on the left bank (facing downstream) a machine maintenance corridor with be cut to allow access. The access corridor will not be within the SAC boundary.

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Figure 2-4: Aqueduct to Confey College

2.4.1.4 Section 4 Aqueduct to Distillery Road Retirement Home From the aqueduct to Distillery Road retirement home. ACDEF will be required to be carried out. From this retirement home to 100m upstream of R148 bridge, DEF will be required and access will be from the scout hall and/or at the retirement home and machines may have to work from within the channel. Upstream directly of R148 bridge ACDEF will be required, significant deposition occurs here due to an upstream amenity area.

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Figure 2-5: Aqueduct to Distillery Road Retirement Home

2.4.1.5 Upstream of Kildare bridge (outwith of the SAC) Upstream of Kildare bridge (outwith of the SAC) ACDEF will be required, with works programmed upstream of Balfeaghan Bridge next year. Access is not an issue here.

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3 Screening Assessment Results

3.1 Introduction An Appropriate Assessment screening assessment, addressing Stage 1 of the process, has already been completed for the Ryewater Arterial Drainage Scheme (JBA Consulting, 2015). This identified that likely significant effects on Natura 2000 may occur as a result of the proposed maintenance activities and therefore a Stage 2 Appropriate Assessment is necessary. The Stage 1 Screening Assessment was conducted in line with guidance produced for the OPW in 2014 (Ryan Hanley, 2014a, b and c). This methodology is based on source > pathway > receptor chain principles and involves assessing likely significant effects on Natura 2000 sites within the zone of influence of the proposed drainage maintenance in relation to three pathways: 1. Surface water 2. Land & air 3. Groundwater The screening assessment involved assessing the impacts of drainage maintenance operations within the arterial drainage scheme, and its zone of influence, in relation to each of the three pathways individually. Conclusions were then drawn to identify which channels within the scheme that could impact upon the Natura 2000 site - Rye Water Valley/Carton SAC (001398). Figure 3-1: Channels with potential impacts via surface water pathways and the Rye Water Valley/Carton SAC

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Figure 3-2: Rye Water Valley/Carton SAC (red shading) extends from Carton House to Leixlip (NPWS, 2015)

3.1.1 Surface Water Pathways As a result of the screening assessment (JBA Consulting, 2014) maintenance activities on those watercourses shown in Figure 3-1 were identified as potentially resulting in significant adverse impacts on Rye Water Valley/Carton SAC via surface water pathways.

3.1.2 Land & Air Pathways As a result of the screening assessment (JBA Consulting, 2015) it was identified that the proposed maintenance works overlap with Rye Water Valley/Carton SAC. Consequently, it was determined that drainage maintenance activities could significantly impact upon Natura 2000 site - Rye Water Valley/ Carton SAC via land and air pathways and as a result this pathway was screened in for further assessment. The scheme watercourse C1 (River Rye Water) passes directly through the Louisa Bridge area where NPWS have noted that the designated features of the Natura 2000 site occur. Petrifying springs also occur at the back of Intel upstream of Louisa Bridge as noted by previous surveys on behalf of Intel.

3.1.3 Groundwater Pathways As a result of the screening assessment (JBA Consulting, 2015) it was identified that, the River Rye Water occurs in the GWB of the Rye Water Valley (IE_EA_G_071) and this GWB supports the designated features of the Natura 2000 site - Petrifying springs which is a priority habitat. The GWB also indirectly supports the snail species as they rely on the groundwater fed habitats of the Petrifying springs and marsh habitat at Louisa Bridge.

3.2 Screening Assessment Conclusions The Screening Assessment (JBA Consulting, 2015) identified that the sites detailed in Table 3-1 were likely to be significantly affected by drainage maintenance operations undertaken within the Ryewater Arterial Drainage Scheme. These conclusions are based on the assumption that all drainage maintenance activities are to be undertaken on all watercourses, embankments and structures during the life of the plan (2016-2020).

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Table 3-1: Screening Assessment Conclusions Pathway of Impact Comment Site Surface Land and Air Groundwater Water There is potential for the conservation interests of the Natura 2000 site to be Rye Water impacted by all pathways given that the Valley/Carton habitats present are groundwater SAC (001398) dependent and have connectivity to surface water, and that scheme watercourses fall within the site itself. Note: Red = likely significant effect Green = no likely significant effect

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4 Natura 2000 sites within the Zone of Influence of Drainage Maintenance Activities

4.1 Introduction This chapter provides baseline information on the Natura 2000 site within the Zone of Influence of the drainage maintenance activities (i.e. that screened into the assessment as detailed in Table 3-1). A short description of the site is provided, along with details of the qualifying interest/special conservation interests, conservation objectives, the attributes used to define favourable conservation status and site vulnerabilities. However, for some sites, site specific conservation objectives have not yet been developed for the qualifying interest/special conservation interest present. As this is the case for the Rye Water Valley/Carton SAC attributes have been taken from similar sites where the same qualifying interest interests are present, and these are assumed to be appropriate for this site.

4.2 Rye Water Valley/Carton SAC (001398) The Rye Water Valley/Carton SAC extends is located on the Rye Water, a tributary of the River Liffey. The watercourse within the Carton Estate is dammed at several intervals, creating a series of lakes with fringes of Reed Sweet-grass Glyceria maxima, Yellow Iris Iris pseudacorus, Reed Canary-grass Phalaris arundinacea, Reedmace Typha latifolia, Water Forget-me-not Myosotis scorpioides, Marsh Marigold Caltha palustris and starworts Callitriche sp. (NPWS, 2013a). Other habitats within the SAC include a small clump of willows Salix spp. with varied ground flora, and old demesne woodlands with deciduous and coniferous species (NPWS, 2013a). These woodlands support a range of notable bird species. Rare plant species within the site include Hairy St. John's-wort Hypericum hirsutum which is legally protected under the Flora (Protection) Order 1999, along with Hairy Violet Viola hirta (however, this plant has not been recorded in the site in recent years), Green Figwort Scrophularia umbrosa a Red Data Book species, and the rare Myxomycete fungus Diderma deplanatum which is found in the woods at Carton Demesne. The Red Data Book species Blue Fleabane Erigeron acer is also found growing on a wall at Louisa Bridge (NPWS, 2013a). At Louisa Bridge there are marsh, mineral spring and seepage areas which support a good diversity of plant species, including stoneworts, Marsh Arrowgrass Triglochin palustris, Purple Moor-grass Molinia caerulea, sedges Carex spp., Common Butterwort Pinguicula vulgaris, Marsh Lousewort Pedicularis palustris, Grass-of-Parnassus Parnassia palustris and Cuckooflower Cardamine pratensis. The marsh vegetation in these area near Louisa Bridge support the rare Narrow-mouthed Whorl Snail Vertigo angustior and Desmoulin's Whorl Snail Vertigo moulinsiana. The scarce dragonfly Orthetrum coerulescens has also been recorded in this area (NPWS, 2013a). The Rye Water is also a spawning ground for Trout and Salmon, and White-clawed Crayfish Austropotamobius pallipes are also present at Leixlip (NPWS, 2013a).

4.2.1 Additional Note

4.2.1.1 Petrifying springs with tufa formation (Cratoneurion) at Leixlip Spa An unusual feature of the groundwater regime in Co. Kildare is the formation of warm springs that occur in a syncline in the Lucan-Celbridge area. The Leixlip Spa is considered a hydrogeological feature of particular importance in the zone of influence of the Ryewater drainage scheme. Leixlip Spa forms part of a seam of hot springs that extend from Co. Kildare to Co. Meath. Warm springs occur in a syncline in the Lucan-Celbridge area, which allows warmer water to the reach the surface. The Leixlip Spa is located close to the Celbridge Syncline. The Leixlip Spa comprises a wetland area including the petrifying springs, which has developed on five distinct terraces on shallow bedrock. A complex groundwater system is understood to be present at Leixlip Spa and comprises the following, which is supported by the different hydrochemical signatures of the groundwater.

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 A deeper, older, warmer groundwater system, which discharges to the spa well. The groundwater is highly mineralized and iron rich. This groundwater system is considered the main source of groundwater at the spa;  A more recent, shallow groundwater system that flows through conduits in the karstified limestone bedrock and discharges near the spa. Groundwater from the shallow system discharges near rock faces and there is understood to be lateral flow toward the River Rye; and  Deeper older groundwater that flows through a younger groundwater system and mixes with it.

Groundwater flow in the shallow groundwater system at Leixlip Spa is largely through conduits in the karstified bedrock. This indicates that karstified bedrock may be present in this area of Leixlip (Kildare County Council, 2013). In recent surveys for OPW, other tufa springs have been noted along the Ryewater and some may occur that are additional records not currently available on NPWS website. This are given in Figure 4-1 and the full report is in Appendix C. Therefore, there is potential to significantly effect this GWD habitat - Petrifying springs with tufa formation and the species they support. Figure 4-1: Tufa Springs Location

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4.2.2 Qualifying Interests Table 4-1: Qualifying Interests of the Rye Water Valley/Carton SAC (001398) (NPWS, 2015) Code Qualifying Interests Attributes - Habitat area - Habitat distribution - Hydrological regime: height of water table, water flow Petrifying springs with tufa - Water quality 7220 formation (Cratoneurion) - Vegetation composition: typical species

From: Cummeen Strand/Drumcliff Bay (Sligo Bay) SAC Conservation Objectives (NPWS, 2013b) - Distribution: occupied sites - Presence on transect - Presence - Transect habitat quality Narrow-mouthed Whorl Snail 1014 - Transect optimal wetness Vertigo angustior - Habitat extent

From: Cummeen Strand/Drumcliff Bay (Sligo Bay) SAC Conservation Objectives (NPWS, 2013b) - Distribution: occupied sites - Population size: adults - Population density - Area of occupancy Desmoulin's Whorl Snail 1016 - Habitat quality: vegetation Vertigo moulinsiana - Habitat quality: soil moisture levels

From: River Barrow and River Nore SAC Conservation Objectives (NPWS, 2011)

4.2.3 Conservation Objective The Conservation Objective for the Rye Water Valley/Carton SAC is to maintain or restore the favourable conservation condition of the Annex I habitat(s) and/or the Annex II species for which the SAC has been selected (see Table 4-1) (Generic Conservation Objectives NPWS, 2015). Favourable conservation status of a habitat is achieved when:  its natural range, and area it covers within that range, are stable or increasing, and  the specific structure and functions which are necessary for its long‐term maintenance exist and are likely to continue to exist for the foreseeable future, and  the conservation status of its typical species is favourable. The favourable conservation status of a species is achieved when:  population dynamics data on the species concerned indicate that it is maintaining itself on a long‐term basis as a viable component of its natural habitats, and  the natural range of the species is neither being reduced nor is likely to be reduced for the foreseeable future, and  there is, and will probably continue to be, a sufficiently large habitat to maintain its populations on a long‐term basis

4.2.4 Site Vulnerabilities NPWS (2014) identify the following as threats to/pressures on the Rye Water Valley/Carton SAC (001398):  Grazing  Modification of structures of inland water courses  Fertilisation  Continuous urbanisation and dispersed habitation  Sylviculture and forestry  Removal of hedges and copses or scrub  Impacts from roads and motorways

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5 Appropriate Assessment

5.1 Introduction The following chapter assesses the proposed drainage maintenance activities on those channels screened into the assessment (see section 0) in relation to the Rye Water Valley/Carton SAC detailed in Section 4.

5.2 Tufa Springs Survey As the proposed works occur in the Rye Water Valley/Carton SAC and the ecological walkover surveys highlighted the possibility of additional tufa springs occurring in the vicinity of Kellystown between Sandsford Bridge and the Aquaduct, JBA proposed a more detailed spring survey for this area. This was carried out in March 2016 and aimed to identify watercourses, springs and tufa springs in the area as there was a possibility of impacts on groundwater, surface water and tufa springs as a result of the initial proposed works. Upon carrying out an initial site walkover with OPW staff, it was observed that a number of maintenance activities may not be required for this round of maintenance therefore only tree removal is required. In future, however should more maintenance be required and an access route needed, the tufa spring survey can be useful in designing the access route and assessing it. The tufa spring survey is provided in Appendix C.

5.3 Impact Assessment Table 5-1 assesses the screened in Natura 2000 site in more detail and examines where potentially adverse impacts may arise from the sources of impact identified above. Where potentially significant adverse impacts are identified, avoidance and mitigation measures are proposed to offset these impacts. These are discussed in the following sections.

5.4 Identification of Potential Sources of Impact Table 3-1 details which of the possible pathways of impact (i.e. surface water, land and air, or groundwater) have been identified as potentially affecting the screened in Natura 2000 site, the conservation objectives and their attributes. Land, surface water and groundwater pathways have been screened into to the assessment for the Ryewater Arterial Drainage Scheme. Figure 3-1 illustrates which of the channels within the Ryewater Arterial Drainage Scheme are those which could potentially impact upon the identified Natura 2000 site and are consequently screened into the assessment. In the absence of specific details for some parts of the scheme, all channels within the Ryewater Arterial Drainage Scheme have the potential to impact on the Ryewater/Carton SAC. Table 5-1 Pathways of impact on the attributes of the designated features of the Ryewater/Carton SAC. Qualifying Code Attributes Surface Water Groundwater Land Interests Petrifying springs Habitat area with tufa 7220    formation

(Cratoneurion)1 Habitat distribution   

Hydrological regime: height of water table, water flow  

Water quality  

Vegetation composition: typical species   

Narrow-mouthed Distribution: occupied sites 1014 Whorl Snail    Vertigo

1 From: Cummeen Strand/Drumcliff Bay (Sligo Bay) SAC Conservation Objectives (NPWS, 2013b)

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Qualifying Code Attributes Surface Water Groundwater Land Interests angustior2 Presence    Transect habitat quality    Transect optimal wetness   Habitat extent   Desmoulin's Distribution: occupied sites Whorl Snail 1016    Vertigo

moulinsiana3 Population size: adults    Population density    Area of occupancy    Habitat quality: vegetation    Habitat quality: soil   moisture levels

5.4.1 Potential Sources of Impact via Land & Air Pathways The main source of impact via Land & Air Pathways is from the maintenance access corridor. There is potential to impact on all the designated features of the the Rye Water Valley/Carton SAC. Petrifying springs with tufa formation (Cratoneurion), a designated feature of the Rye Water Valley/Carton SAC is of considerable ecological and hydrogeological interest. Petrifying springs is not included in the list of habitats in matrix 3.1A of Ryan Hanley methodology, however this habitat may be affected by activities related to access causing trampling or disturbance. Therefore a potential effect is assumed.

5.4.2 Potential Sources of Impact via Ground Water Pathways The area of concern in relation to Ground Water Pathways is in the area of the SAC where the designated features occur and within the zone of influence. A site walkover with the OPW staff has reduced the potential for impact by avoiding activities with the potential to impact on groundwater (and surface water) pathways of the tufa springs and also indirectly affecting species that rely upon the habitat i.e. Vertigo spp. This avoids impacts through groundwater pathways that may affect the hydrological regime and groundwater quality supporting the designated habitats and species. Also, indirect impacts that may occur on habitat quality, extent, structure and distribution and on species distribution, populations and their supporting habitats. Therefore, the proposed works are to remove two trees as shown in the Project Description. This will be carried out manually and no machines will be permitted for access to the SAC. In the future, the OPW have indicated that an access track may be proposed for this section of river and this will require a detailed design and an ecological and appropriate assessment.

5.4.3 Potential Sources of Impact via Surface Water Pathways Only one Natura 2000 site was identified as potentially being impacted upon via surface water pathways; the Rye Water Valley/Carton SAC. All qualifying interests of this SAC (i.e. Petrifying springs with tufa formation (Cratoneurion), Narrow-mouthed Whorl Snail Vertigo angustior and Desmoulin's Whorl Snail Vertigo moulinsiana) and all of their attributes may potentially be affected via surface water pathways. The following sources of impact are identified as potentially impacting upon the above Natura 2000 sites through surface water pathways:  Release of suspended solids - this can arise from a variety of drainage maintenance activities, in particular the removal of trees in bankside or instream and also in-stream silt and vegetation. It can impact on surface water dependent habitats indirectly through increased turbidity, which can reduce photosynthesis levels and impact upon macrophyte

2 From: Cummeen Strand/Drumcliff Bay (Sligo Bay) SAC Conservation Objectives (NPWS, 2013b) 3 From: River Barrow and River Nore SAC Conservation Objectives (NPWS, 2011)

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communities and macroinvertebrate fauna. This could then impact upon the snail populations supported by the spring and wetland habitats.  Release or changes in nutrient levels - this can arise from a variety of drainage maintenance activities, in particular the removal of in-stream silt and vegetation. It can impact on surface water dependent habitats indirectly through causing eutrophication, which can then cause the growth of algae and more nutrient demanding species, potentially reducing species-richness of the habitats. This could then impact upon the snail populations supported by the spring and wetland habitats.  Changes in water levels/channel morphology - this can arise from a variety of drainage maintenance activities, in particular the removal of in-stream silt and vegetation. It can occur from maintenance activities that deepen and wide the channel back to the original design level. This can impact on surface water dependent habitats indirectly through increased capacity and flow in the channel leading to hydrological impacts. This can also indirectly impact on species supported the wetland habitats. Works on bridges and sluices located on the above channels are similarly considered to result in potential adverse effects.

5.4.4 In-combination Effects Appropriate Assessment requires consideration of the impacts on Natura 2000 sites of drainage maintenance activities in the Ryewater Arterial Drainage Scheme, in-combination with other plans or projects. Potential sources of in-combination effects identified as part of this assessment include:  Undertaking of general agricultural operations by farmers and landowners in areas adjacent to scheme watercourses and embankments which could potentially give rise to impacts of a similar nature to those arising from Arterial Drainage Maintenance operations. This could potentially result in additional periods of disturbance (physical, noise and visual). However, given that agricultural operations, similarly to drainage maintenance operations, are periodic and not continuous and have been ongoing for many decades, resulting in a background level of habituation, the in-combination effects of drainage maintenance and agricultural operations is not likely to be significant.  OPW arterial drainage maintenance operations have been ongoing since the construction of the schemes following the 1945 Arterial Drainage Act, potentially resulting in adverse cumulative effects. However, as the maintenance operations are undertaken to restore the design level only, the hydrological impact will be no greater than originally occurred upon the schemes construction; no further deepening or widening will occur. Given that the designated features are located at Sandford Bridge to the Aquaduct behind Intel and this area is shown to be self cleaning with little silt accumulation and good gravel river bed habitat, no significant impacts have been noted on the hydrological regime and therefore none is likely on the designated features in this area.  On a regional scale, neighbouring Arterial Drainage Schemes could be considered to have an adverse impact on Natura 2000 sites, particularly where large sites fall across two, or more scheme areas. The Kildare Arterial Drainage Scheme for the Lyreen River, in combination with the Ryewater Arterial Drainage Scheme has the potential to impact on the Ryewater River downstream. The Kildare Scheme for the Lyreen River and it's tributaries is currently undergoing an Appropriate Assessment. The main proposed activity is dredging of accumulated silts and some bankside vegetation management. However, mitigation measures will be put in place to minimise the cumulative impact downstream in terms of surface water quality impacts downstream on the Ryewater. The Kildare Scheme occurs in the Groundwater body of the Dublin Urban - IE_EA_G_005 and over 2km from the Ryewater GWDTE -IE_EA_0_071 and therefore impacts on Groundwater are not anticipated. This aquifer is not expected to maintain regional groundwater flow paths. Groundwater circulation from recharge to discharge points will more commonly take place over a distance of less than a kilometre. The majority of groundwater flow will be a rapid flow in to upper weathered zone but flow in conduits is commonly recorded at depths of 30 to 50 m b.g.l. The aquifer is not considered to have any primary porosity and flow will be through fractures, some of which will have been enlarged by karstification and dolomitisation. Given the distance from the Ryewater and the intervening area of

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Maynooth town and surroundings, no groundwater, land or air pathways occur in terms of the in combination effects.

There are no other known plans/projects on-going or proposed (at the time of this study) which may give rise to any form of cumulative impact on the Natura 2000 sites.

5.5 Avoidance Measures

5.5.1 Avoidance of sensitive areas within the SAC The channel from Sandsford Bridge to the Aquaduct will be accessed to remove two trees within the Ryewater/Carton River SAC, the removal of the trees, in particular the one nearest the Aquaduct will be carried out manually, in order to avoid damage to the Petrifying springs with tufa formation (Cratoneurion). The tree is located directly on the bankside of the wetlands and tufa spring mosaic habitat of the SAC. No access is possible from the wetland or springs to the location of the tree and therefore access will be from the steps on the northern bank from the canal tow path and across the narrow stretch of river at low water flows. This will be carried out manually and no machinery is permitted beyond the canal tow path. A survey of the tufa springs was carried out along the Ryewater channels to establish the locations of this priority habitat. Although there are no tufa springs on the northern bank, there is a groundwater flow over the surface of the banks to the river along what are termed terraces. There is also a waterfall in this area. Therefore, no access track or machinery can be permitted in this area (Appendix C).

5.6 Mitigation Measures The impact of silt and nutrient release produced by bush cutting/branch trimming and silt and instream vegetation management outside of the SAC, on the attributes of the designated features of the Ryewater/Carton SAC outlined in Table 5-1, are considered. Riverine sediments act as nutrient sinks in catchments. Disturbance to these sediments, in the form of dredging and instream works, cause the release and resuspension of nutrients and suspended solids into the water column. Therefore, the control of silt and nutrient release during works adjacent to or within a watercourse is important. In order to minimise the impacts of silt and nutrient release to a watercourse, the operational controls of the works should be considered first and foremost, such as identifying and demonstrating the need for works, the sequence and rate of works, site conditions and tailored working methods specific to a site. These detailed and specifically designed works, if still posing a negative impact to a receptor, should then be complimented by engineered measures. The engineered measures used to control silt during instream works are typically measures such as cofferdams, geotubes, sheet piles, silt curtains, silt screens, oil booms and pneumatic curtains (Francingues & Thompson, 2006). Similar devices are recommended by the Scottish Environment Protection Agency and the Environment Agency in their best practice guides for sediment management and pollution prevention control (SEPA, 2010; EA, 2012). The protocols and SOPs in OPW (2011b) - specifically points 2.1, 2.2, 2.3, 3.1 and 3.2 of Environmental Drainage Maintenance Guidance SOP, detailed in Appendix A, do not detail measures which sufficiently meet the obligations for the protection of the designated features of the SAC downstream. Straw bales, as detailed in the SOP as a measure to minimise disturbance, have a high failure rate (Fifeld, 1999) and their use is actively discouraged by the US EPA (EPA, 2014). Straw bales are very permeable, do not work well in high flows, become easily waterlogged and have a high failure rate. Therefore, the maintenance works including A - Silt Management shall be avoided where possible, however where these cannot be avoided in the channels of the Ryewater SAC, they shall follow the mitigation measures outlined below in order to reduce the impact to SAC.

5.6.1 Channel assessment Each channel proposed for maintenance works shall be individually assessed in order to determine whether works are necessary and if so, the type and extent of work to be undertaken. Areas that require maintenance shall be kept to a minimum in order to reduce the level of disturbance and

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risk of silt release. Instream works and bush cutting/branch trimming shall be avoided if possible. Works shall only be carried out if there is a risk to the capacity of the channel or a health and safety risk.

5.6.2 Instream silt and vegetation removal For both options outlined below works shall only take place in low flow conditions and adverse weather conditions shall be avoided. Instream works shall follow CIRIA best practice guidelines.

5.6.2.1 Option 1: Wet instream works With vegetation 'plug' Works shall take place along channel stretches that offer an area of vegetation and substrate that is ≥5m in length, which can be left in situ as a 'plug' in the channel to act as a buffer. This 'plug' must be located between the works and the Ryewater/Carton SAC. The above recommendation shall be coupled by those in section 5.5.2.2 below. Lack of vegetation 'plug' If the habitat is not present downstream of the works to provide a 'plug' then river water samples shall be analysed for suspended solids prior to works. River water samples shall be collected downstream of each OPW channel confluence, which has been identified for maintenance works, and shall be sampled on a weekly basis for a period of 6 months and analysed for suspended solids. The above recommendation shall be coupled by those in section 5.5.2.2 below.

5.6.2.2 Instalment of instream geotextile sediment management measures  Suitable instream geotextile sediment management measures, such as silt curtains, fences and mats, shall be installed prior to the works. The device shall be located either; o downstream of the working area and upstream of the intended vegetation 'plug'. o in the absence of a vegetation 'plug', downstream of the working area.  The working area shall be inspected by a suitably qualified ecologist prior to the commencement of the works and may only proceed on his/her recommendation. If silt plumes are observed downstream of these devices at any time during the works, works must stop immediately.  The resultant spoil and sediment from geotextile sediment management measures shall be placed in an area where it cannot re-enter the channel. This area must be identified prior to the work commencing and shall not be in the path of surface water runoff pathways to the channel.

5.6.3 Tree Removal

5.6.3.1 Sandford Bridge to Aquaduct Areas of bush cutting and branch trimming shall avoid adverse weather conditions and follow the recommendations below;  Works shall be supervised by a suitably qualified ecologist in sensitive areas of the SAC.  Only the trees identified for removal will be removed  Works shall be carried out using soft felling methods - manually. No heavy machinery shall be used in the removal of bankside vegetation or trees. Equipment such as saws, secateurs and strimmer shall be used.  No vehicles or access tracks shall be permitted in the SAC.

5.6.4 Bush cutting/branch trimming

5.6.4.1 All other areas except Sandford Bridge to Aquaduct Areas of bush cutting and branch trimming shall avoid adverse weather conditions and follow the recommendations below;

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 Works shall be supervised by a suitably qualified ecologist in sensitive areas of the SAC.  Sandbags shall be placed between the working area and the watercourse.  Works shall be carried out using soft felling methods. No heavy machinery shall be used in the removal of bankside vegetation or trees. Equipment such as saws, secateurs and strimmer shall be used.  Works shall retain vegetation along the riparian zone of the riverbank. Works shall not expose bear soil.  All vegetation cuttings shall be removed from the channel bank and placed in an area where it cannot re-enter the water, either by wind action or surface water run-off.  Vehicle and machinery operation  Sandbags shall be placed between vehicle tracking areas and the watercourse.  All vehicles and machinery shall be re-fuelled off site.  Vehicles and machinery shall be removed from site at the end of each working day.  Vehicles shall not leave exposed track marks in the vicinity of watercourses. If channels need to be accessed by vehicles over soft ground and there is a risk that soil may be exposed, bog mats shall be laid.

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Table 5-1: Impact Assessment Qualifying Site Name Interests/ Special Potential Source Impact on Attribute and Target Prior to Avoidance / Residual Activity Pathway (site code) Conservation of Impact Mitigation / Avoidance1 Mitigation Measures Impact Interests Petrifying spring habitats for which this SAC is designated are dependent on specific water quality and nutrient requirements. For example, NPWS (2013b) highlights that they require high pH values, alkalinity and dissolved calcium, and oligotrophic conditions. Furthermore, the snail species for which the SAC has been For Channels within designated could also be adversely impacted SAC: upon by declines in water quality, in relation to No silt management both sediments and nutrients, as if the from Sandsford Release of vegetation community present is impacted Bridge to Aqueduct to Petrifying springs with suspended solids upon, attributes such as habitat quality or take place within the tufa formation A Silt Surface habitat extent may decline in quality. Other SAC as none needed Insignificant (Cratoneurion) Release or Management Water attributes such as soil moisture could also be for this round of Rye changes in nutrient impacted upon if community composition or maintenance. Water Narrow-mouthed levels structure is altered. Valley/ Whorl Snail Vertigo For other channels: Carton angustior Drainage maintenance activities could impact Follow mitigation SAC on water quality in the spring habitats, and measures as outlined in (001398) Desmoulin's Whorl consequently impact on the snail species they Section 5.5 Snail Vertigo support, through the release of suspended moulinsiana sediments and nutrients from in-channel silt and vegetation removal which could potentially result in increased turbidity and eutrophication, which could then result in algal blooms.

Maintenance of appropriate hydrological regimes is a key attribute of petrifying spring For Channel within Changes in water habitats. For example, NPWS (2013b) highlight SAC - Sandford Bank Surface levels/channel that petrifying springs rely on permanent Bridge to the Insignificant Protection Water morphology irrigation usually from upwelling groundwater Aquaduct: sources or seepage sources and the height of No details of bank the water and water flow are key attributes for protection are available.

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Qualifying Site Name Interests/ Special Potential Source Impact on Attribute and Target Prior to Avoidance / Residual Activity Pathway (site code) Conservation of Impact Mitigation / Avoidance1 Mitigation Measures Impact Interests this habitat type which define condition. The No bank protection snail species for which the SAC is designated measures to the banks are also indirectly dependent on specific from Sandford Bridge hydrological regimes, and how this impacts on to the Aquaduct due soil moisture conditions and the vegetation to the presence of a communities that support the snails. number of springs (Appendix C) Drainage maintenance activities, such as silt and vegetation management, can result in the For other channels: deepening and widening of channels which Follow mitigation could impact on surface water flows and water measures as outlined in table levels. This could have adverse impacts Section 5.5 on the spring habitats, and the species they support, and consequently a number of attributes, including habitat area, habitat distribution and vegetation composition. However, as the works will restore the system to the design standard only significant changes to the hydrological regime are unlikely. The drainage maintenance activities are therefore unlikely to impact significantly on attributes used to define conservation status. For Channels within Petrifying springs with SAC: tufa formation No access from (Cratoneurion) The use of heavy equipment destroys the plant Sandsford Bridge to and soil structure of marsh and tufa springs. Trampling/Damage Aqueduct within the Narrow-mouthed Trampling by humans and machinery for due to SAC in order to avoid Whorl Snail Vertigo Access Land access can also cause the loss of snail Insignificant machinery/humans damage to the SAC. angustior species. This may cause alterations in habitat access This may be reviewed extent, vegetation community structure and subject to the design Desmoulin's Whorl snail species populations. of an access route Snail Vertigo and detailed moulinsiana assessment of that

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For other channels:

Follow mitigation measures as outlined in Section 5.5 Maintenance of appropriate hydrological regimes is a key attribute of petrifying spring habitats. For example, NPWS (2013b) highlight that petrifying springs rely on permanent For Channel within irrigation usually from upwelling groundwater SAC - Sandford sources or seepage sources and the height of Bridge to the the water and water flow are key attributes for Aquaduct: this habitat type which define condition. The No details of bank Petrifying springs with snail species for which the SAC is designated Protection are available. tufa formation are also indirectly dependent on specific No bank protection (Cratoneurion) hydrological regimes, and how this impacts on measures to the Changes to Bank Surface soil moisture conditions and the vegetation banks from Sandford Narrow-mouthed Groundwater Protection and communities that support the snails. Bridge to the Whorl Snail Vertigo levels Insignificant Ground Drainage maintenance activities, such as silt Aquaduct due to the angustior Channel water and vegetation management, can result in the presence of a number aterations deepening and widening of channels which of springs (Appendix Desmoulin's Whorl could impact on surface water flows and water C). Snail Vertigo table levels. This could have adverse impacts moulinsiana on the spring habitats, and the species they For other channels: support, and consequently a number of Follow mitigation attributes, including habitat area, habitat measures as outlined in distribution and vegetation composition. Section 5.5 However, as the works will restore the system to the design standard only significant changes to the hydrological regime are unlikely. The drainage maintenance activities are therefore

2015s2916 Ryewater Natura Impact Statement v8.0 29

Qualifying Site Name Interests/ Special Potential Source Impact on Attribute and Target Prior to Avoidance / Residual Activity Pathway (site code) Conservation of Impact Mitigation / Avoidance1 Mitigation Measures Impact Interests unlikely to impact significantly on attributes used to define conservation status.

For Channel within SAC - Sandford Petrifying spring habitats for which this SAC is Bridge to the designated are dependent on specific water Aquaduct: No silt quality and nutrient requirements. For example, management required. NPWS (2013b) highlights that they require high no access from pH values, alkalinity and dissolved calcium, Sandsford Bridge to and oligotrophic conditions. Furthermore, the Aqueduct. This may be snail species for which the SAC has been reviewed subject to the designated could also be adversely impacted design of an access Petrifying springs with upon by declines in water quality, in relation to route and detailed tufa formation both sediments and nutrients, as if the assessment of that (Cratoneurion) Silt vegetation community present is impacted route relative to the tufa Management upon, attributes such as habitat quality or Surface springs survey. Narrow-mouthed Changes to habitat extent may decline in quality. Other and Whorl Snail Vertigo Groundwater Access attributes such as soil moisture could also be Insignificant Ground No details of bank angustior quality impacted upon if community composition or water protection are available. Bank structure is altered. No bank protection Desmoulin's Whorl Management measures to the Snail Vertigo Drainage maintenance activities could impact banks from Sandford moulinsiana on water quality in the spring habitats, and Bridge to the consequently impact on the snail species they Aquaduct due to the support, through the release of suspended presence of a number sediments and nutrients from in-channel silt of springs (Appendix and vegetation removal which could potentially C) result in increased turbidity and eutrophication,

which could then result in algal blooms. For other channels:

Follow mitigation

measures as outlined in Section 5.5

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6 Avoidance and Mitigation Measures

6.1 Introduction The Environmental Management Protocols and SOPs developed by OPW (2011b) are routinely followed by OPW operational staff undertaking drainage maintenance works and help to provide a baseline level of environmental protection, with a specific focus on certain species (i.e. Brook, River and Sea Lamprey, White-clawed Crayfish, Otter, Freshwater Pearl Mussel, invasive species and Zebra Mussel). In addition to the measures contained within these documents OPW (2011b), Table 6-1 provides specific avoidance and mitigation measures that should be followed in order to offset the identified potential impacts on the Natura 2000 site. Table 6-1: Specific Mitigation Measures Applicable OPW Specific Avoidance and Mitigation Potential Impact Channels1 Measures2 Refuelling will not be undertaken within 50m of a watercourse. The release of suspended solids should be minimised during works.

Release of suspended Where grouting is required on structures, solids prevent grout from entering the watercourse. Release or changes in nutrient levels Where parapet works are required, prevent All channels old cured concrete waste from entering watercourse. Suitable shuttering should be deployed in the event of a concrete pour to ensure no concrete enters the watercourse. Works on all channels should be Changes in water levels/ undertaken in accordance with the channel morphology Scheme's design standard, in order to prevent any new widening or deepening.

1Works on bridges and sluices located on the above channels are also subject to the detailed mitigation/avoidance measures. 2It should be noted that these avoidance and mitigation measures are required in addition to those standard practices detailed in the OPWs Environmental Management Protocols and Standard Operating Procedures (OPW, 2011).

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7 Conclusions The significance of residual impacts of the current arterial maintenance works for 2016 to 2020, on the groundwater dependent terrestrial habitats and species downstream of the works within the Rye Water Valley/Carton SAC are considered insignificant. The most sensitive section for the designated features of the SAC is from Sandford Bridge to the Aquaduct adjacant to Louisa Bridge. It has been established through the site visit and discussions with the OPW that currently no silt management is required. Therefore, no machinery access from Sandsford Bridge to Aqueduct will be needed for the maintenance works for 2016-2020, other than for tree removal by manual means.

7.1 Future works between Sandsford Bridge to the Aquaduct at Louisa Bridge If future maintenance works require machinery access between Sandfords Bridge and the Aquaduct, further assessment will be required. Figure 3.5 in Appendix C outlines a possible access route to minimise the potential impacts on tufa springs. This further assessment will consider the plans for works in this area, subject to the design of an access route and detailed assessment (including as a minimum a AA Screening), of that route relative to the tufa springs survey in Appendix C. Future examination of the feasibility of an access corridor for maintenance along the Ryewater, in particular at Intel, will require a detailed design and Screening for AA as a minimum.

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Appendices A OPW Arterial Drainage Maintenance Service: Environmental Management Protocols and Standard Operating Procedures

2015s2916 Ryewater Natura Impact Statement v8.0 I

The Office of Public Works

Arterial Drainage Maintenance Service

Environmental Management Protocols

Standard Operating Procedures

The Office of Public Works Environment Section West Region Drainage Maintenance Headford Co. Galway Telephone: +353 (0)93 35 456 Fax: +353 (0)93 35 631 The Office of Public Works Arterial Drainage Maintenance Environmental Management Protocols & Standard Operating Procedures

Contents: Current Version Environmental Management Protocols April 2011 Environmental Drainage Maintenance Guidance Notes (10 Steps to Environmentally Friendly Maintenance) April 2011 Lamprey Standard Operating Procedure V2 April 2009 Crayfish Standard Operating Procedure V2 April 2009 Otter Standard Operating Procedure V2 April 2009 Mussels Standard Operating Procedure V2 April 2009 Invasive Species Standard Operating Procedure V2 March 2009 Zebra Mussel Standard Operating Procedure V2 May 2009 Blank OPW/ EREP Audit Form April 2011 NPWS Local Contact Details May 2009 Fisheries Contact Details April 2011 OPW Bridges on National Primary Roads March 2009

This document is uncontrolled in hard copy format. Hard copies should be validated against the revision level of the online version prior to use. w ww.opw.ie ENVIRONMENTAL MANAGEMENT PROTOCOLS

ARTERIAL DRAINAGE MAINTENANCE SERVICE (APPLICABLE TO ENGINEERS, TECHNICIANS AND FOREMEN)

PART I – OPERATIONS MANAGEMENT

COMMUNICATIONS - STATUTORY STAKEHOLDERS  By the end of September of each year, each Drainage Region to forward a draft copy if its Annual Works Programme for the coming year to OPW’s Environment Section, and to the Inland Fisheries Ireland (IFI) EREP Project Manager who will review it for appropriate sites and study locations for the Environmental River Enhancement Programme 2008 -2012.  By end of November of each year, each Drainage Region to forward the relevant sections of the Finalised Annual Maintenance Programme for the coming year with a copy of appropriate scheme maps, to the National Parks & Wildlife Services (NPWS) Regional Managers and the IFI Directors.  When compiling the programme the type of works proposed should be indicated for each channel under the headings A-F to facilitate the Screening for Appropriate Assessment (AA). A – Silt & Vegetation Management B – Aquatic Vegetation Cutting C – Bank Protection D – Bush Cutting/Branch Trimming E – Tree Cutting F – Bridge/ Structure Repairs  Ideally, approximate timing (season/month) and approximate duration of works should be included for each channel.  Works that fall within SACs, SPAs or NHAs are to be highlighted on the programme.  As a follow up, the Drainage Regions offer the opportunity for a meeting with the stakeholders to discuss the programme and where a meeting is requested, preferable for this to take place as early as possible in the year.  Prior to entry onto a channel contained wholly or partly within an SAC, SPA or NHA, three weeks notice in advance of entry, and for SAC & SPA an AA Screening Statement/Conclusion Statement must be completed and forwarded through the NPWS District Conservation Officer.

INTERIM STAKEHOLDERS MEETINGS  In addition to the start of the year stakeholder meeting to overview the Annual Works Programme, Regional Offices will offer and facilitate a schedule of more frequent and catchment focused meetings.  The need and the frequency of these meetings will be determined on a regional basis in partnership with the relevant stakeholders.  Typically a frequency of every 2-3 months to discuss the following 2-3 months work on the catchment, identifying any further environmental sensitivities, appropriate mitigating measures, follow up joint site visits where deemed beneficial and flagging any opportunities for added benefit in proposed River Enhancement works.  Typical attendance includes a range of OPW Management Staff, i.e. Engineer, Technician and/or Foreman, NPWS Rangers and/or DCO and IFI Officers.  OPW Engineer will compile minutes of the meeting to record attendance and a brief account of main decisions and follow up actions.  Any channel specific information resulting from these meetings, such as timing requests should be entered into the Records Database in accordance with the National Recording Process.  Fruitful consultations with statutory stakeholders such as NPWS and IFI are of critical importance to continuously improving environmental performance. However, in the interest of maximising the efficiency of stakeholders input, Management Staff are as far as practical, to plan their consultative requirements and address a range of aspects in any one discussion forum. Interim Stakeholder Meetings or similar forums offer good opportunities to maximise consultation efficiencies.

CORRESPONDENCE  All Environment related correspondence/complaints should be logged on the Engineering Services Correspondence Database as per normal protocol. Complaints received should be forwarded to the Environment Section should assistance be required.

WALKOVER SURVEYS  As a component to the EREP Project, on a number of channels, EREP team will request for Walkover Surveys as an opportunity to discuss in detail on site the environmental options for a particular channel with a range of relevant stakeholders.  Typical attendance will be an IFI EREP representative, a range of OPW Management Staff and relevant Operational Crew if deemed beneficial, local IFI Officer and/or NPWS Ranger or DCO.  OPW Management Staff to liaise with EREP team and coordinate the site visit with local IFI and NPWS to facilitate their participation if these stakeholders wish to attend.  Environmental procedures as agreed on-site will be recorded by IFI EREP team and issued to the OPW Engineer as part of the design guidance for the particular Enhanced Maintenance works.  Regional Management Staff to ensure that Operational Staff carry out the works in accordance with the agreed procedures.

NATURA 2000 SITE ASSESSMENTS  All scheduled maintenance operations in the vicinity of a Natura 2000 Site i.e. an SAC or SPA, will require Screening for Appropriate Assessment and Stage II Appropriate Assessment where required.  By the end of September of each year, each Drainage Region to forward a draft copy if its Annual Works Programme for the coming year to OPW’s Environment Section to facilitate this process.  Environment Section will procure the Ecological Consultant, collate all the channel lists and issue completed AA Screening Statements/Conclusion Statements to the respective OPW engineers as completed.  The Ecological Consultant will consult with OPW management to define the precise extents of proposed works in each Natura 2000 Site.  In addition, the Ecological Consultant will be carrying out walkover surveys for pre and post maintenance works for a representative number of the sites and OPW Management will be required to facilitate the same.  OPW Management Staff will issue the relevant completed Assessments directly to the NPWS District Conservation Officer.In addition, Environment Section will issue all of the Assessments to the Development Applications Unit, DEHLG, Dun Sceine, Harcourt Lane, Dublin 2.  Preferably for the Assessments to be forwarded to the DCO as soon as it is completed, but in any case with a minimum of three weeks notice before commencement of the works.  Management Staff to implement all prescribed mitigating measures and ensure that Operational Staff are made aware of all relevant site specific mitigating measures.

Current version of Designated Sites GIS Layers available on Socialtext

Environmental River Enhancement Programme (EREP)  After reviewing the draft Annual Works Programme, IFI EREP team will revert to the respective Regional Engineers Office and request follow up meetings as required to discuss aspects of the programme in relation to the EREP.  Enhancement sites require ground truthing to ensure they are technically feasible as envisaged. This is to be coordinated by the IFI EREP team with local IFI and OPW personnel as required.  Sites shortlisted by IFI EREP team for Capital Enhancement works are emanating from a screening process of technical feasibility in terms of gradient and water quality. In the future, sites selected will increasingly be resulting from other requirements such as the Water Framework Directive Programme Of Measures under Morphology.  IFI EREP team in consultation with the local IFI and OPW, will prioritise sites on a basis of best return for investment. IFI EREP team will liaise with the Regional Offices to assist in identifying channels deemed suitable for capital enhancement which should be integrated with the following years work programme. In some cases, a situation may arise where the site selected is not overlapping with the current Annual Works Programme but where feasible and subject to any third party agreement, OPW will accommodate these works.  Similarly for enhanced maintenance works, IFI EREP team in consultation with the local IFI and OPW, will select sites again that are technically feasible and offer best return for investment. These sites will normally be from channels on the current Annual Works Programme.  IFI EREP team will coordinate all the scientific monitoring works, provide the enhancement design details and guidance to OPW Management Staff and maintain a reasonable level of site supervision, proportional to the complexity of the works and the experience of the OPW Staff involved.  Consultations with local IFI through the Interim Stakeholder meetings are encouraged to identify sites suitable for Enhancement works and in some cases the local IFI may also be in a position to produce an enhancement design. All enhancement designs and works are to be coordinated through the IFI EREP team to facilitate formal recording into the national EREP project and allow for biodiversity and/or hydromorphology monitoring if required. Local IFI may coordinate with IFI EREP team or alternatively OPW Regional Staff coordinate directly with the EREP team.  A small portion of channels have more infrequent maintenance cycles and these cases can offer particularly good opportunities for enhanced maintenance type works. Channels programmed where maintenance works have not being carried out for in excess of 10 years, to be flagged to IFI EREP team for possible Walkover Surveys and guidance on appropriate EDM procedures.  Management Staff to ensure that as far as practical, all Operational crews have an opportunity to get experience on these projects.  Each Regional Engineer is to make provision in the Annual Works Programme for Plant & Labour resources in addition to provisions in the Annual Budget for materials subject to expenditure constraints. Typical resources are as follows:

Capital Enhancement Region Target Capital Machine ManWeeks (Km) Costs Weeks East Region 20 €200,000 30 60 South West Region 14 €140,000 21 42 West Region 16 €160,000 24 48

50 €500,000 75 150

Enhanced Maintenance (in conjunction with routine maintenance) Region Target Capital Machine ManWeeks (Km) Costs Weeks East Region 20 15 0 South West Region 14 11 0 West Region 16 12 0

50 38 0

 Progress targets for EREP to be shown on monthly production reports.  OPW are the primary contact point for liaison with landowners including the organising of access and egress for machinery and materials. Brochures on EREP are available in all Regional Offices. Additional copies can be obtained through OPW Environment Section.  Management Staff are encouraged to maximise the use of all available on-site materials such as stone from historical spoil heaps as opposed to importing materials at a higher cost.  In addition, Management Staff are encouraged to maximise synergies with other funding sources such as Fisheries Development grants attained by local Angling Clubs which could combine with OPW plant and labour to supply materials.  In all cases, Inland Fisheries Ireland are the statutory authority to give design guidance to OPW. Angling Clubs or other sectoral funding sources to liaise with the Fisheries authorities in respect of all design and environmental monitoring requirements.  As-Built plans are to be completed by the IFI EREP team for all enhancement works. This will entail a site visit by IFI and relevant OPW Staff where requested. These will be retained by IFI as well as any relevant design information.  IFI EREP team will forward a copy of the As-Built plans to Environment Section who will upload the same to Socialtext for access to the information by all Staff.  At the end of the year, IFI EREP team will forward Environment Section a GIS layer of that year's works for uploading to OPWs GIS records.

Current version of Enhancement GIS Layer available on Socialtext

NATIONAL RECORDING PROCESS  Weekly Record Cards can contain information on Lamprey, Crayfish, Kingfisher, Mussels, Otter and other site specific environmental information as arises.  Environmental information on Cards will be recorded onto the Records Database by each Drainage office. The latest Records Database has been revised to integrate environmental records.  On an interim basis, a copy of all Cards with environmental information to be copied and forwarded to Environment Section by each Drainage Office. This is to allow Environment Section to review the detail of information being recorded, feedback to the Operational crews through the Management Staff and attain a national consistency in the style of information being recorded.  All relevant information to be uploaded to GIS by Environment Section.  All other relevant environmental information sourced by Management Staff whether from direct observations or through stakeholder consultations, should be entered into the Records Database.  Relevant environmental information sourced through the EREP project and related research will be forwarded by IFI EREP team to Environment Section directly for centralised GIS uploading.  On an annual basis, Environment Section will compile an update of Weekly Records Cards species records and make available to all Staff via Socialtext to assist in tracking progress.  On an ongoing basis, Environment Section will make available the various OPW compiled species records to other authorities to assist in contributing to any appropriate national conservation knowledge.  As described above, each drainage office will upload onto the Records Database all environmental information from the Weekly Record Cards and all other broader environmental information attained by Management Staff. Within a few years, it's envisaged that multiple regional Staff will be able to use the new Records Database, and then environmental information from all sources will be uploaded directly by a whole host of Staff. Typically this will include any mitigating agreements for particular channels agreed with stakeholders or any other individuals observation such as protected species presence noted during a separate site visit.

SALMONIDS  As far as practicable, the maintenance works are to be scheduled to accommodate salmonid (Salmon & Trout) spawning areas, as is in place across all regions for many years. This is a widespread measure on many catchments and is most applicable to medium gradient channels with gravel substrate.  Prior to works commencing, consult with local IFI. Ideally, consultations to be conducted through Interim Stakeholder Meetings or alternatively, direct contact in respect of the specific site.  Maintenance operations on salmonid spawning beds typically carried out between July and September but timing subject to adjustment due to local knowledge of IFI.  Raking of spawning gravels to improve spawning capacity also typically carried out between July and September.  River enhancement works to enhance both the fisheries and the broader ecology of the drainage channel are covered under the EREP project.  In the future, as the extent of completed enhancement works increases, there is a risk of damage to structures due to future maintenance. All channels scheduled for maintenance to be checked against GIS records for presence of previous enhancement works. Where a presence is indicated, carry out a site visit as appropriate and in consultation with IFI , devise on-site procedures to protect or enhance existing instream structures.

Current version of Enhancements & Spawning GIS Layers available on Socialtext.

LAMPREY (BROOK, RIVER & SEA) & CRAYFISH  All channels scheduled for maintenance to be checked against GIS records for presence of Lamprey or Crayfish.  In accordance with the SOPs, Operational Staff will closely observe the spoil three times daily and report to the Foreman any Lamprey or Crayfish located.  Mitigating procedures to apply when: ◦ GIS records indicate species presence, or ◦ Operational Staff locate Lamprey or Crayfish during operations, or ◦ Where particularly suitable habitat is identified by an environmental stakeholder.  If significant populations are encountered, notify IFI EREP team and facilitate scientific studies if site deemed suitable by IFI.  If significant populations are encountered, notify NPWS Ranger and local IFI Officer and conduct site visit as necessary.  Combination of Mitigating Measures to be selected as applicable to the site while balancing the Flood Risk Management requirements and a sustainable approach to the conservation of Lamprey and/or Crayfish.  Identify extent of channel applicable and the mitigating measures to apply.  Inform Operational Staff of mitigating requirements.

Suite of relevant Mitigating Measures as follows:

On site measures  Skip sections to retain intact habitat either in one long reach or multiple short reaches.  Maintenance in an upstream direction to avoid secondary disturbance of a species moving downstream. Balance with the advantage of maintenance in a downstream direction where instream vegetation minimises siltation.  Confine maintenance to 2/3 of channel width leaving marginal vegetation and silt intact.  Maximise use of weed cutting bucket particularly where aquatic vegetation removal is the primary objective. This is effective for Lamprey juveniles as they are in the silt. For Crayfish, cutting of “Flaggers” type vegetation is effective but cutting of “water celery” mat type vegetation is less effective as it can result in Crayfish being removed within the weed mass.

Forward planning measures  Annual maintenance of the channel in shorter segments sequentially completing the same over a number of years. Balance with maintaining reasonably operational efficiency in terms of machinery moving, transport, access and egress.  Longer time periods between maintenance cycles e.g. move from 4-6 years to 7 to 8 years. Balance with overall river ecology as longer maintenance cycles will lead to more heavy- scale works.  Timing of maintenance to accommodate Lamprey spawning. Stakeholder consultations between OPW and local IFI for salmomid mitigating purposes, to include consideration of Lamprey spawning. This is to be applied to channels where Lamprey spawning habitat is known as informed by IFI or other stakeholder. For River & Brook Lamprey, no works on relevant spawning channel from end March to start of June subject to adjustment due to local knowledge of IFI. For Sea Lamprey, as they spawn during the summer months, restrictions from late April to early July are required. To be applied to channels where Sea Lamprey spawning is known as informed by IFI or other stakeholder and timing subject to adjustment due to local knowledge of IFI. Note that Sea Lamprey are much less widespread so envisaged that the scale of this mitigation will be very limited.  Loosening spawning bed gravels. Stakeholder consultations between OPW and IFI for salmonid gravel loosening purposes, now to include consideration of Lamprey spawning as above.  Enhance channel profile such as skewed cross section and promote deposition of silt along margins. Integrate with IFI discussions on planning the EREP to avail of enhancement opportunities particularly for channels where Lamprey or Crayfish presence is recorded.  Modification of OPW structures which impede upstream migration. Identification of weirs as barriers to be as informed by IFI or other stakeholder. Where modification designs required, liaison with IFI EREP team to integrate the improvement works into the EREP project. Identification of a bridge apron step attained through ongoing site inspections by OPW Management Staff or other stakeholder. In consultation with IFI, steps at bridges to be modified by a rock armour type ramp or similar. Envisaged that these measures will be of a limited scale on drained channels.

GIS Records:  Where Lamprey or Crayfish are discovered, Operational Staff will have recorded the same on the Weekly Record Cards. Cards with species location information will be uploaded to the Records Database as stated in the National Recording Process.  All new Lamprey spawning location information attained through stakeholder consultation to be recorded on the Records Database in accordance with the National Recording Process.  All database records of species location will be uploaded to GIS by Environment Section.  IFI EREP team conducting ongoing research on Lamprey & Crayfish as a component of the EREP works. Scientific data calculating species density for some sites will be developed and to be supplied by IFI to OPW and uploaded to GIS by Environment Section.

Current version of relevant SOPs: V2 April 2009 Current version of relevant GIS Layers available on Socialtext.

OTTER  Research to date indicates that Otters are widespread across all sizes of drainage channels nationally, hence it is prudent to assume that Otter use any particular site.  In accordance with the Otter SOP, Operational Staff will walkover the works area one week in advance in conjunction with the Health & Safety assessment noting dense cover with access directly to the water that is to be avoided where feasible.  In addition, any recognisable signs of Otter presence observed such as Spraints, Footprints or suspected Holts, will be recorded on the Weekly Record Cards. These signs were identified in Otter Awareness Training carried out across all regions in 2008.  While holts are usually well concealed, where Operational Staff observe a suspected holt such as a burrow opening, in consultation with Management Staff, subject to flood risk management functions, no works to within a 50m buffer each side.

Bridge mammal crossing enhancement  As a component of ongoing consultations with NPWS and other stakeholders, evidence may arise from time to time as to a particular spot for Otter road kill. Typically this can arise where the Otter always traverses the roadway as opposed to going through the bridge. While this scenario is not known to be a widespread issue in Ireland, the highest risk locations are on the National Primary Roads which have the heaviest traffic volumes.  There are 170 National Primary Road bridges on OPW channels as listed in the table referenced below and Management Staff are to have particular regard to these locations if evidence arises on a possible road kill “hot spot”.  Enhancement works will typically take the form of a bolt-on wildlife ledge or similar. Design and configuration is to carried out in consultation with NPWS and relevant Local Authority.  On an annual basis, Environment Section will review the national website www.biology.ie which records Otter road kill reports from the public. Any road kill location which overlaps with an OPW channel will be flagged by Environment Section to the relevant Management Staff.  Current understanding is that Otter road kill is not a significant issue in Ireland. It's envisaged that while the justification for bridge mammal crossing works may arise for some scenarios, these measures will be of a limited scale on drained channels.

Current version of Otter SOP: V2 April 2009 Current version of National Primary Roads & OPW Bridges: March 2009

FRESHWATER PEARL MUSSEL  GIS records from NPWS show the locations of the 91 known FWPM populations in Ireland.  The following OPW channels have been identified as containing FWPM:

Channel Scheme Location Most Recent Record CH9 Corrib Headford Oughterard 2009 C1/21/3 Moy Approx 500yrds from outfall to into L. Cullin 2004 C1 Sect M&N Moy Ballygallagart 2004 C1/21/14 Moy Crossmolina 2008 C1 Dunmanway FRS d/s of the Long Bridge 2003 C1 Owvane Approx 1400 yrds from outfall 2002 C1 Feale d/s Listowel near Scartleigh cemetary 2006 **Owenaher Moy u/s of C1/54 1996 **Brown Flesk River Maine Trib of C1 Maine near Farranfore 1987 ** Galey River Feale Approx 1400yrds u/s of C1/18 near Ahavoher Br. 1950 **River Liffey Ryewater (Lucan) Approx 3.5km d/s C1 Ryewater outfall 1894 ** Although not on OPW channels - these channels may or may not contain populations of FWPM. Works in the vicinity which could impact on a possible population need to be considered in close consultation with local NPWS knowledge.

 While highly unlikely to have instream works in a FWPM habitat, if a new population located by Operational Staff during operations, works to cease.  Notify NPWS and in consultation with NPWS, area to be skipped or non in-stream works carried out as agreed for the specific site.  For operations in the vicinity of known populations, mitigating procedures to apply:  Consult with NPWS and local IFI and conduct site visit as necessary. ◦ Typically only selective non in-stream works adjoining the population. ◦ Works such as removal of a fallen tree is to be completed by lifting clear of the channel to minimise any channel bed disturbance due to the branches being dragged. ◦ Assess need for silt management procedures for works upstream of the population and implement in consultation with NPWS.

Current version of relevant SOPs: V2 April 2009 Current version of FWPM GIS Layer available on Socialtext.

SWAN & DUCK MUSSELS  Swan and Duck Mussels are not strictly a protected species, however they are of conservation interest.  Both species are similar in appearance and habitat requirements and distinguishing between them is not necessary unless local environmental stakeholders can identify the exact species.  As the Mussel SOP, if Operational Staff locate the same, Management Staff will be notified.  Where significant populations are encountered notify NPWS Ranger and local IFI Officer, and where they are interested in visiting the site, facilitate a site visit as necessary.  Identify extent of channel applicable and the mitigating measures to apply.  Typical Mitigating Measures include: ◦ Operational Staff to observe spoil and return any Mussels to the channel whom are expected to recolonise the channel bed. ◦ Maximise use of weed cutting bucket particularly where aquatic vegetation removal is the primary objective. ◦ Skip sections to retain intact habitat either in one long reach or multiple short reaches. ◦ Confine maintenance to 2/3 of channel width leaving marginal vegetation and silt intact.  Record species presence on the Weekly Record Cards which will be recorded on the Records Database.

Current version of relevant SOPs: V2 April 2009

KINGFISHER  Avoid disturbing nesting sites in banks.  Visual sightings of Kingfisher by Operational Staff to be recorded on the Weekly Record Cards.  Sightings by Management Staff to be recorded on the Weekly Record Cards where works in progress or on other occasions, record by separate map or channel reference format.  All sightings to be recorded on the Records Database in accordance with the National Recording Process.  All database records of species location will be uploaded to GIS by Environment Section.  On an annual basis, Environment Section will issue the records to Birdwatch Ireland whom will add to the national Kingfisher database.

Current version of Kingfisher GIS Layer available on Socialtext.

BIRDS  Removal of any abnormally dense layer of vegetation is to be executed between September and February (inclusive) to minimise impacts on nesting birds unless there are other overriding requirements such as Health & Safety.  For SPAs containing important over-wintering bird populations, in consultation with the NPWS, regard to be given to timing or phasing of the works to minimise potential disturbance.

BATS  While the removal of large mature trees is not typically a requirement of maintenance works, where the case arises, in consultation with NPWS, regard to be given to the likelihood of bat roosting habitat.  Typical mitigating measure would be to leave tree in fallen position for 24hrs to allow any bats vacate.  Masonry bridges offer niches and crevices suitable for bat roosts and where masonry bridges are scheduled for maintenance works, regard to be given to the likelihood of bat roosting habitat. Typical maintenance works at low level such as wing wall repair or underpinning foundations have limited potential to impact on bat roosts. Where the case arises that repair works are to be above the high water level such as the upper arch, in consultation with NPWS, assess the potential for the works impacting on bat roosts.  Typical mitigating measure would be to contract a bat specialist to survey for bat presence before works commence, to avoid entombment of any bats.

WETLANDS - BOGS, FENS & TURLOUGHS  All channels scheduled for maintenance which overlap SAC designations to be checked against the list of channels that impinge on Raised Bog, Fen habitat or Turloughs and have regard to any NPWS agreements noted *.  OPW Management Staff to consult with NPWS for expert opinion as to any evidence of ongoing ecological decline of the Bog, Fen or Turlough and judgement on, if the drainage datum set by the Drainage Scheme and its maintenance is an ongoing contributing factor by affecting the hydrological regime of the same.  Where a likely impact is identified, conduct site visit as necessary and in consultation with NPWS, mitigating measures to be selected such as:  Skipping the channel in question while taking cognisance of the flood risk management requirements.  Maximise use of weed cutting bucket particularly where aquatic vegetation removal is the primary objective.  Inspection by OPW line management to assess the possibility of over digging the channel below the original design datum. Presence of an existing water level control such as a bridge floor to be established and alternative reference datum to be installed if deemed warranted.

* Environment Section currently developing a list of channels which overlap with Raised Bog, Fen habitat and Turloughs within SACs. Channels that are subject to a previous NPWS agreement /understanding of the extent of maintenance will be recorded.

Current version of Wetlands channels list available on Socialtext.

INVASIVE SPECIES – PLANTS  Multiple invasive plant species are widespread nationally as described in the SOP and prudent to assume that one or more of these plants can be present on any works site.  At present the OPW does not have any direct responsibility for the management of Invasive species. However to ensure OPW operations are not a vector for these invasives, measures are required to reduce the risk of spread.  Ensure machine washing equipment transported to site for all appropriate machinery movements as described in the Invasive Species SOP.  Ongoing EDM site audits by Environment Section will include confirmation that machine washing was executed in accordance with the SOP for the last applicable machine transfer.  In some cases, OPW will assist other authorities in the control of invasive species. In these projects, the works are typically carried out in partnership between a number of authorities such as IFI, NPWS and relevant Local Authority. As scenarios arise where OPW are requested to assist in an invasive species control project, Management Staff are encouraged to support the multi-authority partnership model which will maximise resource efficiencies for all parties while still achieving a broader environmental good.

Current version of relevant SOP: V2 March 2009

INVASIVE SPECIES – ZEBRA MUSSEL  Zebra Mussels are present in the River Shannon, Grand Canal and are in many lakes such as L Derg, L Ree, L Garra, L Key, L Derragh, Derravaragh, L Sheelin and L Corrib. This species is spreading and it is prudent to assume that works in any large sluggish river or near a lake has potential to contain Zebra Mussel.  For any proposed works in the vicinity of potential Zebra Mussel waters, flag for Operational Staff and ensure particular attention to cleaning procedures for all equipment prior to removal from site.  Any new location of Zebra Mussel uncovered during operations, notify NPWS and IFI for their information.  Record on Weekly Record Sheet which will be uploaded on the Records Database in accordance with the National Recording Process.  On an annual basis, Environment Section will collate the records nationally and issue to any relevant authorities to assist in tracking the species spread.

Current version of relevant SOP: V2 May 2009

TREE MANAGEMENT  A small portion of channels have more infrequent maintenance cycles typically where self cleaning gradients are present. These sites can entail abnormally dense tree cover which may be required to be managed for conveyance or fisheries purposes. Removal of any abnormally dense layer of vegetation is to be executed between September and February (inclusive) to minimise impacts on nesting birds unless there are other overriding requirements.  IFI requests to reduce “tunnelling” on drainage channels to be accomodated where feasible. OPW Management Staff to facilitate a site visit with the IFI Officer as required and devise a selective approach to the tree removal so as to retain a dappling of shade along the channel length.  Excess woody vegetation to be collected and utilised by the following in order of preference: ◦ Reused by adjoining landowner for domestic firewood. ◦ Subject to landowners agreement, stockpile excess to form natural cover and niche habitat, preferably with some connection of cover to the channel e.g. along a hedge leading to the water. ◦ Shred and spread along the adjoining top of bank allowing the material to degrade rapidly and recolonisation of the underlying vegetation.

ENVIRONMENTAL DRAINAGE MAINTENANCE (EDM) GUIDELINES  A portion of operational crews will be audited annually for implementation of the EDM Guidelines and other standard environmental procedures as adopted.  Auditing will be carried out separately by both IFI and OPW Environment Section on a rotational basis to ensure all operational crews are audited at least once every three years.  Audit results will be recorded on a standard format with the following feedback: ◦ All audit results will be forwarded to the relevant Engineer for that Drainage Scheme within two working weeks. ◦ In the event of an audit showing elements of unreasonable non-compliance with procedures, the relevant Engineer will be notified within one working day. ◦ Audit results will be forwarded to OPW Systems Co-ordinator for inclusion in monthly regional benchmarking reports. ◦ IFI EREP team will compile an overall summary of their findings in their end of year report under the EREP project.  Design for Enhanced Maintenance works under EREP will include a design element for full scale implementation of the EDM Guidelines such as Boulder Replacement and Excavating Pools.  Management Staff to ensure that as far as practical, all Operational crews have an opportunity to get experience on these projects.

Current version of EDM Guidelines: April 2011 Current version EDM Audit Sheet: April 2011 PART II – DEPOT MANAGEMENT

DEPOT WASTE MANAGEMENT

 12 Waste Management Plans are available on Socialtext covering the 12 Drainage Offices.  Environment Section will review 2 plans per annum and audit implementation.  Updated Plans together with an overview of findings will be forwarded to the relevant Coordinator and uploaded to Socialtext.

FUTURE REVISIONS

 Envisaged that this set of Protocols will be a fluid document and will be periodically updated as procedures are revised or new procedures introduced. In addition, to be used as a framework document for quality control purposes to reference the latest versions of all supporting information.

Inland Fisheries Ireland March 2011

IFI Region Director Address Telephone Region/Scheme IFI Blackrock William Walsh 15a Main Street 01 2787022 East: Glyde & Blackrock Co. Dee, Boyne, Dublin Blackwater, Bally-Teigue IFI Ballina John Connelly Ardnaree House 096 22788 West: Moy, Bonet Abbey Street Ballina Co. Mayo IFI Ballyshannon Dr. Milton Station Road 071 9851435 West: Donegal Matthews, Ballyshannon Co. schemes, Kilcoo, Donegal Duff IFI Limerick Sean Ryan Ashbourne 061 300238 East: Inny, Brosna Business Park West: Boyle, Dock Road Ballyglass Limerick South: Killimor, Carrighahorig, Nenagh, Groody, Maigue, Deel, Feale IFI Macroom Dr. Patrick Buck Sunnyside House, 026 41221 South: Maine, Macroom Co. Owvane Cork IFI Clonmel Suzanne Campion Anglesea Street 052 80055 East: Brickey Clonmel Co. Tipperary IFI Galway Amanda Mooney The Weir Lodge 091 563118 West: Corrib Earl's Island Headford, Mask, Galway IFI Dr. Ciaran Byrne Unit 4 Swords 01 8842600 All Business Campus Balheary Rd Swords Co. Dublin

EREP Project Dr. Karen Unit 4 Swords 01 8842624 All Manager Delanty Business Campus Balheary Rd Swords Co. Dublin

(Note: Completed flood relief schemes are not listed but proposed works should be discussed with the relevant local IFI) OPW Bridges (numbering 170) intersecting National Primary Roads.

Scheme Channel ID Bridge No. National Route type Bridge Name Glyde and Dee C2 (7C) B80 N01 Glyde and Dee C2 (7E1) B839 N01 Glyde and Dee C2 (7E1) B840 N01 Broadmeadow and Ward C2/1 B230 N02 Broadmeadow and Ward C2/1 B239 N02 Broadmeadow and Ward C2 B204 N02 Coolatrath br. Broadmeadow and Ward C2/3 B243 N02 Broadmeadow and Ward C1/6/1 B86 N02 Broadmeadow and Ward C1/6/1/1 B96 N02 Broadmeadow and Ward C1/6 B68 N02 Broadmeadow and Ward C1 B16 N02 Boyne C1 B4 N02 Slane br. Glyde and Dee C2 (7H) B101A N02 Glyde and Dee C2 (17) B179 N02 Glyde and Dee C2 (14B) B118 N02 Glyde and Dee C2 (14) B867 N02 Glyde and Dee C2 (1) B30 N02 Glyde and Dee C2 (13) B111 N02 Glyde and Dee C2 (16B4) N02 Glyde and Dee C1 (1) B15 N02 Aclint Br Glyde and Dee C29 (2) B441 N02 Glyde and Dee C29 (3) B443 N02 Glyde and Dee C25 (8) B341 N02 Glyde and Dee C25 (7D1) B672 N02 Monaghan Blackwater C1/1/5 B7 N02 Monaghan Blackwater C1/1/5/6/1 B1 N02 Monaghan Blackwater C1/3/5/2 B8 N02 Monaghan Blackwater C1/3/6/3 B1 N02 Hoaf Br Boyne C1/8/24 BX1 N03 Boyne C1/8/23 B733 N03 Boyne C1/8/21 B723 N03 Boyne C1/8/16 B644 N03 Boyne C1/8 B126 N03 Clavens Br Boyne C1/8/8 B294 N03 Boyne C1/12/1 B875 N03 Dillon's Br Boyne C1/12/7 B915 N03 Owenmore Behy Bridge BX1 N04 Boyle C6/7/5 B2 N05 Ballanagare Br Boyle C6/7/1/4 B2 N05 Boyle C6/7/1 B3 N05 Cloonshanville Br Boyle C1/3/2/1 B4 N05 Boyle C1/9/1 B1 N05 Boyle C1 B4 N05 Old Lung Bridge Boyle C1/8 B1 N05 New Lung Bridge Boyle C1/45 B8 N05 Moy C1/31/2 B3 N05 Moy C1/31 B4 N05 Moy Not on a channel B2 N05 Trimoge Moy Not on a channel B2 N05 Moy Not on a channel B1 N05 Moy C1/30/3/1 B1 N05 Moy C1/28/2 B3 N05 Moy C1/28/1 B4 N05 Moy C1/25 B6 N05 Moy C1/23/3 B2 N05 Moy C1/23 B9 N05 Moy Not on a channel B1 N05 Moy C1/21/1/5/2/2 B3 N05 Moy C1/21/1/5/2/11 B2 N05 Moy C1/21/1/5/1/15 B1 N05 Moy C1/21/1/5/2/18 B1 N05 Moy C1/21/1/5/2/19 B2 N05 Moy C1/21/2/5/2/20/4 B1 N05 Boyle C1/44/15 B2976 N06 Boyle C1/44/17 B2984 N06 Boyle C1/64/1/11/6 B3337 N06 Boyle C1/64/1/11 B3303 N06 Miltownpass Br. Boyle C1/64/1/11/4 B3319 N06 Boyle C1/64/1/11/4/2 B3331 N06 Boyle C1/64/1/13/2 B3330 N06 Boyle C1/64/1/13 B3372 N06 Rochfort Br. Boyle C1/64/1/13/4 B3384 N06 Brosna C27 (1) B150 N06 Brosna C1 (1) B11 N06 Kilbeggan Br. Brosna C17 (1) B143 N06 Brosna C17 (SE) B726 N06 Brosna C17 (5) B138 N06 New Br Brosna C17 (4) B135 N06 Corrib Clare C1 B3 N06 Quincentennial Br. Nenagh C1/9 B23 N07 Ollatrim Br Nenagh C1/9/24 B4 N07 Monaghan Blackwater C1/1/6/1 B11 N12 Tyholland Br Blanket Nook C1/3 B23 N13 Swilly embankments E9 B1 N14 Swilly embankments C1/5 B9 N14 Deele and Swillyburn C1 B6 N14 Deele and Swillyburn C1/11 B19 N14 Deele and Swillyburn C2 B20 N14 Abbey C1/4 B39 N15 Abbey C1/4 B31 N15 Abbey C1/3A B30B N15 Abbey C1/2 B21 - B23 N15 Abbey C1/1 B18 N15 Duff C1 B1 N15 Bonet C1/12/3 B1 N16 Bonet C1/12 B5 N16 Bonet C1/12 B4 N16 Bonet C1/12 B2 N16 Bonet C1 B5 N16 Bonet C1/13/2 B1 N16 Bonet C1/13 B1 N16 Moy C1/50/2 B3 N17 Moy C1/50 B4 N17 Moy C1/48/3 B2 N17 Moy C1/48 B3 N17 Moy C1/45/4 B2 N17 Moy C1/45 B13 N17 Moy C1/30/5/9 B3 N17 Moy C1/30/5/9 B15 N17 Corrib Mask CM4/43/4 B2 N17 Corrib Mask CM4/34 B10 N17 Corrib Mask CM4/34/2 B2 N17 Corrib Clare C3/30 B8 N17 Corrib Clare C3/30/4 B1 N17 Corrib Clare C3/26 B2 N17 Corrib Clare C3/26/9 B1 N17 Corrib Clare C3/26/1 B3 N17 Corrib Clare C3/12/2 B1 N17 Corrib Clare C3 B14 N17 Corrib Clare C3 B2 N17 Claregalway bridge Fergus D7 B3 N18 Owenagarney C2 B1 N18 Owenagarney C4 B3 N18 Coonagh Embankments C10 B9 N18 Coonagh Embankments D13 B113 N18 Coonagh Embankments B1 N18 Maigue C1/36 B1 N20 Helena's br. Maigue C1/37/1 B3 N20 Maigue C1/37 B1 N20 Maigue C1 B23 N20 Creggane br. Maigue C1/33 B1 N20 Cappanafaha br. Maigue C1/30 B2 N20 Ballynabanoge br Maigue C1/26 B1 N20 Maigue C1/15 B10 N20 Maigue C1/10/5 B3 N20 Maine C1/28 BX1 N21 Maine C1/34 B117 N21 Maine C1/35 BX2 N21 Deel SR C12/2/2 B125 N21 Deel SR C12/2/2/2 B127 N21 Deel SR C12/2/1 B123 N21 Deel SR C10 B95 N21 Ballyfraley br. Deel SR C8 B76 N21 Reens br. Maigue C1/17/10 B1 N21 Maigue C1/17/8 B2 N21 Maigue C1/17/5 B1 N21 Maigue C1 B1 N21 Adare br. Maigue C1/15 B5 N21 Maine C1 B3 N22 Maine br. Maine C1/32 B110 N23 Dysert br. Maine C1/33 B114 N23 Killfinnaun br. Maine C1 B9 N23 Herbert br. Groody C1/4 B29 N24 Groody C1 B4 N24 Groody C1/7 B53 N24 Groody C1/9 B56 N24 Moy C1/9/1 B1 N26 Moy C1/9 B2 N26 Moy F/282 B N26 Moy C1/14 B1 N26 Moy RIVER B3 N26 Moy C1/37 B1 N26 Moy C1/38 B1 N26 Moy RIVER B2 N26 Cloongullaun br. Moy C1/39 B3 N26 Moy C1/39 B6 N26 Moy C1/39 B9 N26 Moy C1/39/3 B1 N26

Otter Wildlife Passes and OPW Drainage Channels

• It has been brought to the attention of the OPW that there may be a need for small mammal passes on some of the maintained channels.

• The National roads constitute less than 6 percent of roads in this country, approx. 3 National Primary and 3 percent National Secondary. In spite of this they a carry over 42 percent of the traffic. It is for this reason that the focus will be on the National Primary road crossings.

• The national road kill survey was analysed and the data from the web site “www.biology.ie” was cross-referenced against OPW channel locations and the results were inconclusive, as the web page is not widely used. It appears for now that OPW channel road crossings have no affect on the deaths of otters as per this information.

Next Steps: 1) Consult NPWS throughout all regions to review any evidence of otter road kills on National Primary roads or are they aware of any other such road deaths. 1. Where there appears to be mammal deaths on National Primary roads that intersect OPW channels it will be seriously considered to install in the bridge (where possible) a small mammal pass to allow ease of access for otters.

Otter Habitat Disruption • Otters, along with their breeding and resting places, are protected under the provisions of the Wildlife Act, 1976, as amended by the Wildlife (Amendment) Act, 2000. They are also included in Annex I and Annex IV of the Habitats Directive, which is transposed into Irish Law in the European Com- munities (Natural Habitats) Regulations (S.I. 94 of 1997), as amended.

Otter Pass Details • Mammal Ledges and underpasses should be constructed parallel to the watercourse. • Underpasses should be of a diameter of 600mm up to a length of 20m. Where lengths exceed this the pipe should be increased to 900mm diameter • An underpass should be no more than 50m of the watercourse with channels or fencing guiding the animals to it.

Where there is sufficient space under the bridge for a ledge the following should be provided: • Fencing: See “figure 1; Specification for Mammal Resistant Fencing” in the NRA, National Roads Au- thority, Guidelines for the Treatment of Otters Prior to the Construction of National Road Schemes, for more detail. Also, Design Manual for Roads and Bridges, DMRB Volume 10, Section 1, Part 5, Chapter 9. • A bolt on ledge can be used under a bridge where there is no dry passage. The bolt on ledge should provide otters with a dry walkway of between 300mm and 450mm wide, constructed from 4.5mm Durbar patterned galvanised plate. • At some sites, considerations of responsibility, cost, aesthetics or practicality might indicate the use of a solid ledge; this is most likely where an existing otter-ledge has proved to be sited too low to offer dry passage at spate conditions. A solid ledge can be created in 3 ways; concrete bagging, shuttering plus new concrete and concrete blocks. • See (OPW, 2007), (DMRB, 2001) and (NRA 2006) for further Details

References • NRA (2006) – National Roads Authority, Guidelines for the Treatment of Otters Prior to the Construc- tion of National Road Schemes. • NRA (2005) – National Roads Authority, Guidelines for the Crossing of Watercourses During the Construction Of National Road Schemes. • OPW (2007) – Series of Ecological Assessments on Arterial Drainage Maintenance No. 4, Ecological Impact Assessment (EcIA) of the Effects of Statutory Arterial Drainage Maintenance Activities on the Otter (Lutra lutra). • OPW (2006) – Screening of Natura 2000 Sites for Impacts of Arterial Drainage Maintenance Opera- tions. Environment Section, Engineering Services, Office of Public Works. • DMRB (2001) - Design manual for roads and bridges (DMRB). Volume 10, Section 4 Environmental Design and Management Nature Conservation. Part 4 HA 81/99 Nature conservation advice in relation to otters. Section 1, Part 9 HA 81/99.

B Ecological walkover survey of Ryewater Valley/Carton SAC

2015s2916 Ryewater Natura Impact Statement v8.0 I

2015s2916 Ryewater Natura Impact Statement v8.0 II

2015s2916 Ryewater Natura Impact Statement v8.0 III

C Tufa Springs Survey

2015s2916 Ryewater Natura Impact Statement v8.0 I

Tufa Springs Survey, Ryewater Valley/Carton SAC, Leixlip, Co.Kildare

Tufa Spring Report July 2016

Office of Public Works Main Street Headford Co Galway Ireland

JBA Project Manager Tom Sampson 24 Grove Island Corbally Limerick Ireland Revision History

Revision Ref / Date Issued Amendments Issued to

V1.0 / July 2016 Office of Public Works V1.1 / August 2016 Office of Public Works Contract This report describes work commissioned by the Office of Public Works, by a letter dated 05/06/2015. The Office of Public Works representative for the contract was Tony Brew. Niamh Sweeney and Anne Murray of JBA Consulting carried out this work.

Prepared by ...... Anne Murray BSc.Hons MCIEEM Senior Ecologist

Reviewed by ...... Tom Sampson BSc MSc FRGS C.WEM MCIWEM Purpose This document has been prepared as a Draft Report for the OPW. JBA Consulting accepts no responsibility or liability for any use that is made of this document other than by the Client for the purposes for which it was originally commissioned and prepared. JBA Consulting has no liability regarding the use of this report except to the OPW. Copyright © JBA Consulting Engineers and Scientists Ltd 2016 Carbon Footprint A printed copy of the main text in this document will result in a carbon footprint of 58g if 100% post-consumer recycled paper is used and 73g if primary-source paper is used. These figures assume the report is printed in black and white on A4 paper and in duplex. JBA is aiming to reduce its per capita carbon emissions.

2015s2905 Tufa Springs survey OPW 2016 v1.1

Contents 1 Introduction ...... 1 1.1 Background ...... 1 2 Tufa Springs ...... 1 2.1 Chemistry of Tufa formation ...... 1 2.2 Ecology of Petrifying Springs with Tufa formation (Cratoneurion)...... 2 3 Petrifying Springs Survey 2016 ...... 5 3.1 Current Conservation Status - Petrifying Springs with Tufa Formation (Cratoneurion) ...... 5 3.2 Hydrogeology ...... 5 3.3 Survey Results 2016 ...... 8 3.4 Recommendations ...... 8 3.5 Possible Route for Access Corridor ...... 9

List of Figures Figure 3-1: Study Area at Sandsford Bridge to Aqueduct ...... 6 Figure 3-2: Quaternary Map for the Study Area (GSI, 2016) ...... 6 Figure 3-3: Groundwater Vulnerability (GSI, 2016) ...... 7 Figure 3-4: Tufa springs survey map ...... 8 Figure 3-5: Possible access route ...... 9

2015s2905 Tufa Springs survey OPW 2016 v1.1

1 Introduction

1.1 Background JBA Consulting has been commissioned by the Office of Public Works (OPW) to provide environmental consultancy services in relation to statutory arterial drainage maintenance activities that will take place over the five-year period 2016-2020. The Ryewater Arterial Drainage Scheme is located in County Kildare. It includes 32km of watercourse and no embankments, 9km of which flow through the SAC. The watercourse is the Ryewater and it discharges into the River Liffey at Leixlip, downstream of the Louisa Bridge. The River Ryewater at Leixlip, Co Kildare, a designated Natura 2000 Site and is noted for the Priority Annex I Habitat - Petrifying Springs with Tufa formations. This report summarises the survey carried out by JBA ecologists for tufa springs. Petrifying springs are of considerable ecological and hydrogeological interest and are listed as a priority habitat on Annex I of the EU Habitats Directive. They occur where lime-rich water emerges from below ground and deposits calcium carbonate or ‘tufa’ on the ground surface. Tufa appears as a whitish, crunchy coating on plants and on the ground surface. It may become consolidated into a porous rock, often forming a cascade down a hillside.

2 Tufa Springs

2.1 Chemistry of Tufa formation There are various theories regarding the development of modern day petrifying springs. The most widely held view is that infiltrating groundwater passing through the soil zone becomes charged in carbon dioxide (CO2) which is well in access of that already available within the atmosphere. This output of CO2 in the soil zone is largely due to oxidation of reduced organic matter (e.g. CH2O) which is expected to be catalysed by micro-organisms (Andrews at al., 1996); (see (1) below). Further CO2 can be produced by plant root respiration, although this is a minor source (Freeze and Cherry, 1979).

(1) CH2O + O2 → CO2 + H2O

The CO2 produced combines with H2O to form carbonic acid (H2CO3) (see (2) below).

(2) CO2 + H2O ↔ H2CO3 When infiltrating water leaves the soil zone and enters the groundwater system it is then expected that weathering reactions associated with rock forming minerals will consume the carbonic acid. If carbonate minerals are present (such as calcium carbonate CaCO3) within the drift or bedrock these are normally dissolved to saturation levels. These weathering reactions consuming carbonic acid can act as a buffering mechanism on the pH value (see (3) below). Dissolved concentrations of calcium (Ca2+) and bicarbonate (HCO3-) are increased.

(3) CaCO3 + H2CO3 ↔ Ca2+ + 2 (HCO3-) If carbonate mineral dissolution occurs above the water table under conditions where abundant CO2 is present, the dissolution is referred to as taking place under open-system conditions. The more CO2 that is present, the greater the amount of carbonic acid is produced and the more CaCO3 can be dissolved. If the H2CO3 consumed by carbonate weathering is not replenished by the addition of further CO2, for example below the groundwater table, then the system is termed a closed system. When water saturated with calcium carbonate in equilibrium with carbon dioxide levels or partial pressures greater than atmospheric comes into contact with the atmosphere, CO2 diffuses out. This causes the solution to become supersaturated and precipitation of the carbonate, or ‘tufa’, previously dissolved with the ground may result (see (4)). At spring sources this adheres to the organic and inorganic substrate forming characteristic tufa mounds and cascades; upon and around which a distinctive habitat is known to flourish.

2015s2905 Tufa Springs survey OPW 2016 v1.1 1

(4) Ca(OH)2 + CO2 = CaCO3 + H2O The physical action, such as turbulent flow, in a stream or natural spring will speed the released of CO2. Supersaturation is also promoted by an increase in temperature as groundwater emerges at the surface, and by any increase in concentration brought about by potential evaporation at the surface. In addition to these physic-chemical processes, supersaturation may be promoted by biological influences such as photosynthesising of bryophyte species (mosses and liverworts and possibly algae) removing CO2 from solution, thereby upsetting the equilibrium in the same way as loss of CO2 to the atmosphere. Some plants such as stonewort alga, Chara, can also take up bicarbonate ions by active transport, resulting directly in the precipitation of calcite (Coxon 1994). Many of these elements driving precipitation are consistent with an increased productivity in summer months. The relative importance of physic-chemical and biological factors in the precipitation of calcium carbonate is less certain and likely varies between sites. However, loss of CO2 to the atmosphere is accepted as the major cause of carbonate precipitation in speleothems (e.g. stalactites’) (Holland et al., 1964), and has also been reported to play a major role in tufa deposition (Pentecost 1978 and 1981).

2.2 Ecology of Petrifying Springs with Tufa formation (Cratoneurion)

2.2.1 Habitat Description The European description of this habitat is as follows: Annex I Habitat 7220 * Petrifying springs with tufa formation (Cratoneurion) Hard water springs with active formation of travertine or tufa. These formations are found in such diverse environments as forests or open countryside. They are generally small (point or linear formations) and dominated by bryophytes (Cratoneurion commutati). Plants: Arabis soyeri, Cochlearia pyrenaica (in sites with heavy metals), Pinguicula vulgaris, Saxifraga aizoides. Mosses: Catoscopium nigritum, Cratoneuron commutatum, C. commutatum var. falcatum, C. filicinum, Eucladium verticillatum, Gymnostomum recurvirostrum. In the Boreal region also Carex appropinquata, Epilobium davuricum, Juncus triglumis, Drepanocladus vernicosus, Philonotis calcarea, Scorpidium revolvens, S.cossoni, Cratoneuron decipiens, Bryum pseudotriquetum.

2.2.1.1 Corresponding categories United Kingdom classification: "M37 Cratoneuron commutatum-Festuca rubra spring community" and "M38 Cratoneuron commutatum-Carex nigra spring community". German classification: "220102 kalkreiche Sicker- und Sumpfquelle", "220302 kalkreiche Sturzquelle", "220402 kalkreiche, temporäre Sicker- und Stumpfquelle", "220502 kalkreiche, temporäre Sturzquelle". Nordic classification: "3521 Philonotis-typ" and "3522 Cratoneuron-typ". Can form complexes with transition mires, fens, chasmophytic communities of cold and humid environments and heaths and calcareous grassland (Festuco-Brometalia). In order to preserve this habitat of very limited expanse in the field, it is essential to preserve its surroundings and the whole hydrological system concerned. Malmer, N. (1971). Förslag till riktlinjer för en enhetlig klassificering av myrvegetation i Norden. In: IBP i Norden 7. Universitetsforlaget, Oslo, pp. 45-58. (European Commission, 2007) In Ireland this habitat is classified Fossitt (2000) under Springs – Calcareous Springs FP1. Petrifying springs (petrify: to become like stone) form due to the encrustation of twigs, mosses, leaves etc. which over time can either become replaced with calcite, retaining physical structure, or be preserved in a casing of calcite (tufa).

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Water also appears to ‘turn to stone’ when depositing tufa in waterfalls. ‘Cratoneurion’ is the scientific name given to the vegetation of a classic tufa-forming spring. It refers to the moss species Cratoneuron commutatum (now named Palustriella commutata) that, along with only a few other species, is usually abundant at these sites1. These mosses encourage the precipitation of tufa on their leaves and continue to grow away from it. This moss cover is the basis for the development of complex and specialised biological habitat on what was originally a completely inorganic substrate (i.e. the tufa). The habitat often remains lacking in soil or peat development (Heery, 2007).

2.2.1.2 Vegetation of Petrifying Springs The very common feature of various accounts is the abundance and dominance of bryophytes (mosses and liverworts) at the point at which tufa is most actively forming. This may be as much to do with the constantly wet, spongy nature of the substrate as with the extremely calcareous nature of the water and the tufa itself. Rodwell’s (1995) National Vegetation Classification (NVC), for Britain, includes two categories of vegetation that are associated with tufa formation: M37 Cratoneuron commutatum–Festuca rubra springs. These are ‘classic’ tufa springs with the Cratoneuron moss dominant “in large swelling masses”. Although there are 41 vascular herbs listed, each individual site was poor in species, which often occurred as a few scattered individuals. Interestingly, Equisetum telmateia was not recorded. M38 Cratoneuron commutatum–Carex nigra springs. These are richer in both bryophytes and vascular plants, and may sometimes come to resemble a rich fen. They are usually found on gently sloping firmer ground than M37 and are grazed by sheep and deer. Kelly and Cross (2003) describe a wet woodland category – C3 Alder-ash woodland with giant horsetail (Equiseto-telmatejae-Fraxinetum association). They describe it as: “…rather open woodland, on slopes flushed with calcareous groundwater, characterised by beds of giant horsetail Equisetum telmateia, which grow up to 1 m high but collapse and die down in winter. Trickles and runnels support swards of a golden-green moss with feather-like branching, Cratoneuron commutatum. Old shoots of this moss frequently become covered by a whitish crust of calcium carbonate – literally petrified! Soils are constantly wet and are saturated with lime (pH 7.7-8.2); sometimes a hard crust of tufa covers the soft mud beneath”. White and Doyle (1982) also cite the presence of greater horsetail Equisetum telmateia as indicating a calcareous spring (Cratoneurion). Equisetum telmateia was also included in the CORINE description of hard water springs Cratoneuron (tufa and calcareous), quoted in Foss (2007). 'The Flora and Conservation Status of Petrifying Springs in Ireland' is a PhD research study which investigates the diversity of flora and the contributing environmental factors in a wide range of petrifying spring sites throughout the country (unpublished). The PhD surveys constitutes the first comprehensive field survey of this habitat and provides a baseline for future monitoring of the habitat. The surveys form one of the main supporting sets of data for the Article 17 Report. The following habitat description is taken from Ireland's Article 17 Report to the EU 2013: Petrifying Springs with Tufa Formation (Cratoneurion) have been defined as springs and seepages where tufa is actively deposited and where characteristic species of bryophytes are dominant or abundant. Characteristic bryophyte species are Palustriella commutata, P. falcata, Eucladium verticillatum, Pellia endiviifolia, Cratoneuron filicinum, Bryum pseudotriquetrum and Didymodon tophaceus. Characteristic vascular plants are Festuca rubra, Carex panicea and Equisetum telmateia. Petrifying springs may occur as (i) clearly defined spring heads with consolidated tufa, (ii) spring heads with an associated tufaceous flush, or (iii) seepage areas with tufa formation. The last-named type often occurs within alkaline fens and the vegetation forms a continuum between the two habitat types so that petrifying springs are not clearly demarcated from the surrounding fen vegetation. Three Subtypes of petrifying spring vegetation can be distinguished depending on

1 However, it must be noted that Palustriella commutata etc are not confined to tufa-forming situations and can occur in more normal base-rich springs and seepages.

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the setting of the spring: Woodland springs; Coastal springs; and Springs of inland, open habitats. Springs occurring on the Benbulbin Range constitute a distinct group of high conservation value. Description of the vegetation of two Irish sites follows, one is upland at Slieve Bloom and the other forms part of the Ryewater Valley/Carton SAC at Leixlip within the survey area for this report. Given the time of year of the current survey, it was not a suitable time of year for a flora survey in early March.

2.2.1.3 Fauna of petrifying springs Tufa-forming springs are known be a habitat for a specialised fauna – tufobiont species-adapted to an environment that has very many unusual features compared to surrounding habitats. In simple terms, among the most immediately apparent special conditions are: a constant, but often low, water flow of even temperature; a constantly wet, but essentially terrestrial, open mossy substrate; almost complete lack of peat or soil development; an (over) abundance of accreting calcium and other water chemistry aspects. Organisms with non-emergent life styles such as crustaceans (ostracods) and molluscs are said to be more at home here than insects. Crustaceans have an obvious use for excess calcium in shell building, and constant temperatures mean the possibility of year round reproduction. There are, however, some insect species adapted to these places (Heery, 2007). Caddis fly larvae, chironomids (non-biting midges) and beetles were sampled at Pollardstown Fen tufa springs (Murray, 1996 quoted in Otte, 2003). Furthermore, these species, which are relatively high on the food chain, are living off myriad lower forms that also need to be specially adapted. “Larger petrifying springs form tufa cones that constitute singular habitats with several interacting plant and animal communities” (CORINE, 1994). “It was soon established that the specialised physio-chemical environment was home to a great diversity of plants and animals with some peculiar adaptations to a rapidly depositing environment. Rocky, soil free surfaces are not usually recognised for their richness of the biota. Plants have few opportunities to root. But few rocks match travertine in the range of hardness and texture, and the source of water is chemically diverse. Consequently, active travertine surfaces often support a surprising biota which in turn influence the deposition” (Pentecost, 2005). Moorkins carried out a molluscan survey as part of Heery’s study at Slieve Bloom. 31 snail species were recorded, including common species and “a number of rare and one legally protected species”. There was a remarkable diversity of molluscan species found during the short survey, including a number of rare and one legally protected species. While the last tufa site surveyed had the largest area of Cratoneuron commutatum, it had the smallest species diversity. Similarly, the dry beech litter without the influence of the spring had a low species diversity with common species only present. The sites that had the combination of tufa spring with other supporting habitats have yielded both high diversity and high quality indicator species, making them hot-spots of molluscan interest and are very likely to also be hot-spots for other invertebrate groups. The shaded spring sites on valley slopes with mixed woodland have an excellent mix of wet woodland mollusc fauna, including two nationally rare species, Spermodea lamellate and Zenobiella subrufescens.

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3 Petrifying Springs Survey 2016 The Petrifying Springs survey was carried out by two JBA ecologists on March 16th 2016. Prior to the survey a desktop study was carried out to examine the geology, hydrogeology and groundwater quality of the area. In particular, evidence of seeps, flushes, cascades and streams were searched for to form a baseline to the survey work. The importance of groundwater and surface water quality to the Priority Annex I Habitat of tufa springs has been highlighted in the draft NIS for this site.

3.1 Current Conservation Status - Petrifying Springs with Tufa Formation (Cratoneurion) As there is no evidence of decline, Range and Area are assessed as ‘Favourable’. Plant species composition, environmental variables and threats and pressures were investigated across a wide range of sites (76% of the total area). Structure and Functions were assessed as ‘Unfavourable Inadequate’ as a small proportion of sites (6.7% of the area assessed) had been damaged by drainage or other inappropriate forms of management. Future prospects are assessed as ‘Unfavourable Inadequate’ in view of agriculture-related pressures of land reclamation, unsuitable grazing levels, pollution and water abstraction as well as more isolated instances of road drainage and outdoor leisure pursuits pressures. Education of landowners was identified as a means of promoting conservation of the habitat. Differences between the present assessment and the 2007 submission are due to improved knowledge of the habitat rather than a real change in its conservation status. (NPWS, 2013)

3.2 Hydrogeology Information obtained from the GSI website (Figure 3-1 and Figure 3-2) indicate that the areas surrounding the Ryewater in the Study Area largely comprises tills and gravels derived from limestones. The northern bank of the Ryewater consists of a glaciofluvial terrace with some meltwater channels flowing down the terraces into the Ryewater channel. A report for KCC noted the following: An unusual feature of the groundwater regime in Co. Kildare is the formation of warm springs that occur in a syncline in the Lucan-Celbridge area. The Leixlip Spa is considered a hydrogeological feature of particular importance in the zone of influence of the Ryewater drainage scheme. Leixlip Spa forms part of a seam of hot springs that extend from Co. Kildare to Co. Meath. Warm springs occur in a syncline in the Lucan-Celbridge area, which allows warmer water to the reach the surface. The Leixlip Spa is located close to the Celbridge Syncline. The Leixlip Spa comprises a wetland area including the petrifying springs, which has developed on five distinct terraces on shallow bedrock. A complex groundwater system is understood to be present at Leixlip Spa and comprises the following, which is supported by the different hydrochemical signatures of the groundwater.  A deeper, older, warmer groundwater system, which discharges to the spa well. The groundwater is highly mineralized and iron rich. This groundwater system is considered the main source of groundwater at the spa;  A more recent, shallow groundwater system that flows through conduits in the karstified limestone bedrock and discharges near the spa. Groundwater from the shallow system discharges near rock faces and there is understood to be lateral flow toward the River Rye; and  Deeper older groundwater that flows through a younger groundwater system and mixes with it.

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Groundwater is known to occur close to surface in some parts of the terraces and this provides the possibility of tufa springs occurring in the Study Area additional to that previously indicated on the Site Synopsis for the Ryewater Valley/Carton SAC at Leixlip SPA. Given the presence of underlying limestone and source of calcium carbonate the conditions are suitable for tufa forming springs. The GSI maps indicate that Groundwater Vulnerability is considered High in the study area with Extreme/Rock at or near Surface in on the north eastern bank where groundwater flows overground on the terraces (Figure 3-3). Figure 3-1: Study Area at Sandsford Bridge to Aqueduct

Figure 3-2: Quaternary Map for the Study Area (GSI, 2016)

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Figure 3-3: Groundwater Vulnerability (GSI, 2016)

3.2.1 Vegetation Survey of Leixlp Spa (Lyons, 2009) One part of the Study Area was studied in detail at Leixlip SPA in 2009 by Lyons. The site consists of a series of terraces descending to the Rye Water River. Lime-rich water seeps from the underlying limestone bedrock via a number of springs and flows slowly overland towards the Rye Water. Tufa formation (the deposition of calcium carbonate on the ground surface) occurs where the spring water emerges from below ground. This is a characteristic feature of the priority habitat. These tufa-covered areas are overlain by shallow water and contain scant vegetation. The predominant species are the moss Palustriella commutata, the stonewort Chara hispida and the vascular plants Eleocharis quinqueflora, Eriophorum angustifolium and Triglochin palustre. The springs are surrounded by flush vegetation classified as PF1 Rich Fen and Flush (Fossitt, 2000). PF1 flush vegetation is species-rich and forms an integral part of the calcareous spring system. Mosses are abundant. The dominant species is Drepanocladus cossonii, accompanied by Palustriella commutata and Calliergonella cuspidata. Vascular plants include Carex dioica, C. viridula subsp. bra chyrrhyncha, Anagallis tenella, Parnassia palustris, Pinguicula vulgaris, Crepis paludosa, Lychnis flos-cuculi, Valeriana officinalis, Succisa pratensis, Equisetum palustre, Briza media and the orchids Gymnadenia conopsea, Dactylorhiza incarnata and D. fuchsii. Flush vegetation is surrounded by Wet Grassland (GS4) in open areas and by Tall Herb Swamp (FS2) in shady places. Species of note present within areas of tufa deposition include Carex viridula subsp. brachyrrhyncha, Eleocharis quinqueflora, Triglochin palustre and the moss Palustriella commutata. These are typical species of base rich fens and flushes.

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3.3 Survey Results 2016 A survey of the Study Area in March 2016 indicates that there is an additional tufa forming habitat and a number of streams/flushes along the Ryewater behind Intel on the southern bank of the Ryewater and on the northern bank running from the Shaughlin's Glen. Given the time of year it was not the appropriate time for a vegetation survey. Given the close interconnection between groundwater features and the terrestrial habitats along this stretch of river, it will be important that any proposed works and also the design an access track carefully to avoid any direct and indirect impacts on the surface and groundwater and the habitats which they support. The area is noted as showing high vulnerability in terms of groundwater. Given a number of sensitive ecological features along the Ryewater at this stretch, the area should be treated as highly sensitive. Figure 3-4 shows the location of the tufa springs, waterfalls, flushes and streams associated with the Ryewater in this area. Figure 3-4: Tufa springs survey map

3.4 Recommendations Observation of the channel conditions and hydromorphology during the survey and previous site visits has identified that this reach of the Ryewater is self-cleansing and does not require maintenance, other than specific tree removal as identified in the NIS. Upstream flow and level is controlled by the number of weirs and channel and vegetation maintenance would provide any extra drainage benefits to land upstream. At present the establishment of a machine maintenance access corridor is not necessary. Ongoing inspection of the channel on an annual basis is recommended to monitor the condition of the watercourse and identify the need for maintenance in the future. The results of this report will feed into the NIS for the Arterial Drainage Maintenance activities in order to complete the NIS. Between Sandsford Bridge and Louisa Bridge we specifically recommend that no maintenance work is undertaken (other than specific tree removal) and a maintenance access corridor is not established This is in line with the OPW standard operating procedures to skip maintenance on the most sensitive channel reaches.

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3.5 Possible Route for Access Corridor Figure 3-5 shows a possible access route for future maintenance to minimise the potential impacts on the highly sensitive tufa springs. The route will need to be reviewed by the OPW for health and safety and operational matters prior to establishment. A final design would need to be considered in the context of sensitive ecological receptors such as Badger Sett, Woodland area, Otter holt, Springs, Tufa Springs etc. Therefore, the final design would require both a Screening for AA as a minimum and also an assessment of impact and avoidance of sensitive ecological receptors that are not part of the SAC but occur along the proposed access route. Figure 3-5: Possible access route

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References EPA (2015). EPA Maps. [ONLINE] Available at: http://gis.epa.ie/Envision. [Accessed May 2016]. Commission of the European Communities. (2007) Interpretation manual of European Union habitats: EUR 27. Brussels: European Commission DG Environment. NPWS (2013). The Status of Protected EU Habitats and Species in Ireland. Overview Volume 1. Unpublished Report, National Parks & Wildlife Services. Department of Arts, Heritage and the Gaeltacht, Dublin, Ireland. Editor: Deirdre Lynn. NPWS (2015). National Parks and Wildlife Service. [ONLINE] Available at: http://www.npws.ie/protected-sites/sac/002298. [Accessed 08 September 15].

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References Department of Environment, Heritage and Local Government (2009) Appropriate Assessment of Plans and Projects in Ireland - Guidance for Planning Authorities. Fossitt, J.A. (2000) A Guide to Habitats in Ireland. The Heritage Council, Dublin. JBA Consulting (2014) Hazelhatch (Shinkeen) Arterial Drainage Scheme: Stage 1 Appropriate Assessment Screening. Unpublished Report. Kelleher, C. and Marnell, F. (2006) Bat Mitigation Guidelines for Ireland. Irish Wildlife Manuals, No. 25. National Parks and Wildlife Service, Department of Environment, Heritage and Local Government, Dublin, Ireland. NPWS (2015) Conservation objectives for Rye Water Valley/Carton SAC [001398]. Generic Version 4.0. Department of Arts, Heritage and the Gaeltacht. NPWS (2014) Rye Water Valley/Carton SAC Natura 2000 - Standard Data Form. http://www.npws.ie/sites/default/files/protected-sites/natura2000/NF001398.pdf [date accessed 11th August 2015]. NPWS (2013a) Rye Water Valley/Carton SAC Site Synopsis. http://www.npws.ie/sites/default/files/protected-sites/synopsis/SY001398.pdf [date accessed 11th August 2015]. NPWS (2013b) Cummeen Strand/Drumcliff Bay (Sligo Bay) SAC (site code 627) Conservation objectives. http://www.npws.ie/sites/default/files/protected- sites/conservation_objectives/CO000627.pdf [date accessed 11th August 2015] NPWS (2011) River Barrow and River Nore SAC Conservation Objectives. http://www.npws.ie/sites/default/files/protected-sites/conservation_objectives/CO002162.pdf [date accessed 11th August 2015]. OPW (2014) The Office of Public Works Arterial Drainage Maintenance Activities 2014: Killimor Arterial Drainage Scheme Natura Impact Statement (NIS). Unpublished Report. OPW (2011a) Arterial Drainage Maintenance and High Risk Channel Designation Programme 2011-2014 Habitats Directive Assessments. Environment Section Engineering Services Office of Public Works. Unpublished Report. OPW (2011b) Arterial Drainage Maintenance Service Environmental Management Protocols and Standard Operating Procedures. Unpublished Report. Ryan Hanley (2014a) Office of Public Works Arterial Drainage Maintenance Environmental Services 2013. Stage 1: Appropriate Assessment Screening Methodology for the Maintenance of Arterial Drainage Schemes. Methodology. Unpublished Report. Ryan Hanley (2014b) Office of Public Works Arterial Drainage Maintenance Environmental Services 2013. Stage 1: Appropriate Assessment Screening Methodology for the Maintenance of Arterial Drainage Schemes. Moy Validation Report. Unpublished Report. Ryan Hanley (2014c) Office of Public Works Arterial Drainage Maintenance Service 2014-2018. Source > Pathway > Receptor Chains for Appropriate Assessment. Unpublished Report.

2015s2916 Ryewater Natura Impact Statement v8.0 I

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