Dublin City Council Comhairle Cathrach Bhaile Atha Cliath CLANMOYLE FLOOD ALLEVIATION SCHEME ENVIRONMENTAL REPORT Revision B - July 2012 Clanmoyle Flood Alleviation Scheme Environmental Report CONTENTS 1. INTRODUCTION 2 1.1 This Document 2 1.2 Wad Flood Relief Scheme – Project Overview 2 1.3 Planning and Regulatory Context 3 1.4 Project Context 7 2. RECEIVING ENVIRONMENT, IMPACTS AND MITIGATION 10 2.1 Introduction 10 2.2 Human Beings 10 2.3 Water Quality 15 2.4 Ecology 19 2.5 Geology and Hydrogeology 25 2.6 Noise and Vibration 28 2.7 Air Quality and Climate 31 2.8 Cultural Heritage 32 2.9 Landscape and Visual Assessment 33 3. ENVIRONMENTAL CONSIDERATIONS FOR MIDDLE WAD FLOOD ALLEVIATION SCHEME 39 4. CONCLUSION 41 Appendix A – Appropriate Assessment Stage 1 Screening Report Appendix B – Drawings Appendix C – Geophysical Survey Nicholas O’Dwyer Ltd. i July 2012 Clanmoyle Flood Alleviation Scheme Environmental Report 1. INTRODUCTION 1.1 This Document This Environmental Report has been prepared by Nicholas O’ Dwyer Ltd. on behalf of Dublin City Council (DCC). It supports the Part 8 Planning Application for the Clanmoyle Flood Alleviation Scheme, the first phase of the WAD Flood Alleviation Scheme. This Environmental Report constitutes an environmental assessment of the potential impacts of the proposed Clanmoyle Flood Alleviation scheme on the environment in general. Section 2 of this document addresses the main EIS themes, assesses any potential environmental effect of the scheme and proposes mitigation measures as appropriate. A brief appraisal of environmental considerations for Phase 2 the Middle WAD Flood Alleviation scheme is presented in Section 3 for completeness although Part 8 planning is not being progressed for this scheme at this time. 1.2 Wad Flood Relief Scheme – Project Overview The Wad River drains a catchment area of approximately 483 hectares, including parts of Ballymun, Santry, Donnycarney, and Killister to the seafront at Clontarf in North County Dublin. The Wad River, originally an open channel, has been completely replaced with culverts and pipelines of varying dimensions over the 6km route from Albert College Park Road to the seafront at Clontarf. There have been a number of historical flooding events reported within the Wad catchment area. Recent flooding events occurred in August 2008 and July 2009 as a result of extreme rainfall in the catchment. These events caused significant damage to property and as a result the Wad Catchment Study was initiated to recommend a scheme which would reduce the risk of flooding within the catchment. A further flood event in October 2011 compounded the need to progress suitable flood alleviation measures. The aim of the Wad Catchment Study was “to carry out a full catchment study of the River Wad from the source to the outlet at Clontarf”. The study was required to recommend a scheme which would reduce the risk of flooding within the catchment. Nicholas O’Dwyer Ltd. 2 July 2012 Clanmoyle Flood Alleviation Scheme Environmental Report The recommended flood alleviation scheme comprises three area based sub- schemes as follows  Sub Scheme 1: Clanmoyle Flood Alleviation Scheme  Sub Scheme 2: Middle Wad Flood Alleviation Scheme  Sub Scheme 3: Upper Wad Flood Alleviation Scheme. This Environmental Report supports Part 8 Planning Application for Sub Scheme 1, the Clanmoyle Flood Alleviation Scheme which is being progressed at this time. 1.3 Planning and Regulatory Context 1.3.1 Environmental Impact Assessment (EIA) The primary legislation governing EIA in Ireland is the Local Government (Planning and Development) Regulations 2001 and the European Communities (Environmental Impact Assessment) Regulations 1989 to 2006. Projects requiring EIA are listed under Annex I and II of the 2001 Regulations. Though Flood Relief Works are listed under Annex II, Section 10; “Canalisation and flood relief works, where the immediate contributing sub- catchment of the proposed works (i.e. the difference between the contributing catchments at the upper and lower extent of the works) would exceed 1,000 hectares or where more than 20 hectares of wetland would be affected or where the length of river channel on which works are proposed would be greater than 2 kilometres” This project does not qualify under these criteria as the entire catchment area of the WAD River is only 483 hectares, no wetland is affected and there is no existing river channel on which works are proposed. The Planning and Development (Strategic Infrastructure) Act 2006, provides for the making to An Bord Pleanala of applications for planning permission in respect of certain proposed developments of strategic importance, and for certain other amendments to the Planning and Development Acts 2000-2004. Though canalisation and flood relief works are listed under Schedule 7 of this Act, the criteria for making an application to the Bord are identical to the criteria in the Nicholas O’Dwyer Ltd. 3 July 2012 Clanmoyle Flood Alleviation Scheme Environmental Report Local Government (Planning and Development) Regulations 2001 (listed above) and therefore an application to the Bord is not necessary. 1.3.2 Sub Threshold EIA Article 120(1) of the Regulations 2001 states that “where a local authority proposes to carry out a sub-threshold development, and where it considers that the development would be likely to have significant effects on the environment, it shall prepare, or cause to be prepared, an EIS in respect thereof. Guidance as to how the local authority determines if the project is likely to have a significant effect on the environment is contained in Environmental Impact Assessment (EIA) Guidance for Consent Authorities regarding Sub-threshold Development (DEHLG, August 2003). There is a requirement for account to be taken of the;  Characteristics of the proposed development;  Location of the proposed development; and  Characteristics of potential impacts As of the 13 June 2011, the Planning Department of Dublin City Council considers the Clanmoyle Flood Relief Scheme ‘sub threshold’ for the purposes of EIA and considers that the impacts are unlikely to be sufficient to warrant preparation of a full EIS. Notwithstanding the above and following consultation with the Planning Department it has been determined that in the interest of observing best practice it would be prudent to prepare an Environmental Report1 addressing the main EIS themes to assess any potential environmental effects of the scheme. 1.3.3 Appropriate Assessment Irrespective of the need for an EIA, due to the Natura 2000 site designations within the Tolka Estuary and Dublin Bay, Dublin City Council must take into account Regulation 29 of the Natural Habitats Regulations S.I. No. 94/1997 which outlines the obligations of the competent authority to undertake an Appropriate Assessment where a development is likely to have potentially significant effects, 1 Ref. Guidelines on the information to be contained in Environmental Impact Statements EPA (2002) - sections 2.4.4 & 2.4.7 Nicholas O’Dwyer Ltd. 4 July 2012 Clanmoyle Flood Alleviation Scheme Environmental Report either individually or in combination with other developments on a Natura 2000 site i.e. a Special Area of Conservation (SAC) or a Special Protected Area (SPA). In accordance with the Habitats Directive S.I. No. 94/1997 any plan or project that has the potential for a significant effect on an SAC or SPA must be screened in order to determine whether an Appropriate Assessment is required. The recommended Wad Flood Alleviation Scheme drains directly to the Sandymount Strand/Tolka Estuary SPA (Site Code 004024) and is within 5km of a number of other Natura 2000 sites including the South Dublin Bay SAC (Site Code 000210), the North Dublin Bay SAC (Site Code 000206), and the North Bull island SPA (Site Code 004006). Therefore the scheme must be screened to determine if an Appropriate Assessment is required. A Stage 1 Screening Report was prepared in December 2011 by Nicholas O’ Dwyer Ltd. on behalf of Dublin City Council to assess the potential impacts of Sub Scheme 1, the Clanmoyle Flood Alleviation Scheme and Sub Scheme 2, the Middle Wad Flood Alleviation Scheme on Natura 2000 sites. This document is included in Appendix A. It concluded that there would not be significant impacts from Sub Scheme 1 and 2 on Natura 2000 sites. 1.3.4 Dublin City Development Plan 2011-2017 Development in the Wad catchment area is governed by Dublin City Council (DCC). TheDublin City Development Plan states that ‘The active pursuit of flood risk management strategies and sustainable urban drainage systems also enables the city to adapt to climate change.’ The implementation of the Wad Catchment Study recommendations is an essential element for providing adequate drainage infrastructure to the area. The sustainable development of the area cannot progress without the necessary infrastructure and services. Therefore the recommended scheme not only complies with the requirements of the area development plan but is fundamental to its success. Nicholas O’Dwyer Ltd. 5 July 2012 Clanmoyle Flood Alleviation Scheme Environmental Report 1.3.5 Part 8 The Wad Flood Alleviation Scheme is subject to an accompanying application for consent under Part 8 of the Planning and Development Regulations 2001 (S.I. 600 of 2001). Part 8 Planning Permission is currently being sought for the various elements of the Sub Scheme 1, the Clanmoyle Flood Alleviation Scheme. This Environmental Report supports the Part 8 Planning Application for this scheme. The design and scope of works for Sub Scheme 2, the Middle Wad Flood Alleviation Scheme and Sub Scheme 3, the Upper Wad Flood Alleviation Scheme have yet to be finalised. Part XAB Part XAB is a new provision of the Planning & Development Acts, 2000-2010, which places a greater emphasis on the impacts a plan or project may have on sites or species of a particular ecological value (Part XAB refers to new provisions within Part X of the amended legislation). Every land-use plan prepared by Local Authorities, on its own or in combination with other plans or projects, must be screened to determine if any significant effects are likely to arise on the integrity of the Natura 2000 Network (Appropriate Assessment Screening Report). Following the screening procedure, it may be determined that a Natura Impact Report (NIR) is required to be prepared. The NIS would need to be compiled for submission to An Bord Pleanala and the procedure as per Section 177AE of Part XAB, inserted after Part X by Section 57 of the Planning and Development Act. As the Stage 1 Screening Report for Appropriate Assessment for the proposed scheme completed in December 2011 determined that there would be no significant impact on Natura 2000 sites from the proposed works, the normal Part 8 procedure is followed, save that the screening report completed by the Planning Department shall be placed on display with the Part 8 documentation in Accordance with Article 83 and 249 (6) of the Planning and Development (Amendment) Act 2010. 1.3.6 Foreshore License A Foreshore License is required for the outfall at Clontarf. The Foreshore Acts (1933-2005) require that a lease or license must be obtained from the Minister for the Environment, Heritage and Local Government for the carrying out of works or placing structures or material on, or for the occupation of or removal of material from the foreshore. Dublin City Council submitted a foreshore license application Nicholas O’Dwyer Ltd. 6 July 2012 Clanmoyle Flood Alleviation Scheme Environmental Report for the Clontarf outfall to the Department on the 27th May 2010. As of the 18th of June 2012 a Foreshore License has yet to be granted by the department. 1.4 Project Context 1.4.1 The Need for Flood Alleviation Measures Flooding events occurred in August 2008, July 2009 and October 2011 as a result of extreme rainfall in the catchment. These events caused disruption to road and rail traffic, significant damage to property and posed a significant risk to public safety. The Wad Flood Alleviation Scheme is required in the interest of public safety and to reduce the risk of future damage and disruption from flooding within the Wad catchment. 1.4.2 Description of WAD Flood Alleviation Scheme A description of the key components of the Wad Flood Alleviation Scheme is outlined below. The locations of individual components of the scheme are presented in Figure 1.1 overleaf. Sub Scheme 1: Clanmoyle Flood Alleviation Scheme  Construction of a flood routing culvert from Clanmoyle (A) to Clontarf Golf Club (B)  Attenuation storage in Clontarf Golf Club (C) Sub Scheme 2: Middle WAD Flood Alleviation Scheme  New Culvert from Collins Park to Clontarf Golf Club (D)  New culvert across the Howth Road (E)  A new outfall culvert to the sea in Clontarf (F). This outfall will be located less than 20 metres to the West of the existing outfall. Sub Scheme 3: Upper WAD Flood Alleviation Scheme  Localised works will be required to the west of the M1 in order to alleviate the risk of flooding Nicholas O’Dwyer Ltd. 7 July 2012 Clanmoyle Flood Alleviation Scheme Environmental Report Clanmoyle Flood Alleviation Scheme Figure 1.1 Location of key components of the proposed Middle Wad and Clanmoyle Flood Alleviation Schemes 1.4.3 Description of Clanmoyle Flood Alleviation Scheme A detailed description of the key components of Clanmoyle Flood Alleviation Scheme is outlined below. The locations of individual components of the schemes are presented in the appended drawings. This proposal forms the first phase of a wider proposal to address the flooding issues experienced in the Wad catchment. The overall scheme will provide an additional tunneled culvert from Collins Park to the Clontarf Golf Club, the tunneled upgrade of the culvert capacity at Howth Road and an additional outfall to the bay. The layout of the scheme is detailed on drawing numbers 20446-PP- 01 to 07. The Clanmoyle Flood Alleviation scheme for which this permission applies affords protection to the houses in Clanmoyle who have experienced flooding as a result of extreme rainfall events in recent years. The proposal provides for an inlet Nicholas O’Dwyer Ltd. 8 July 2012