Strategic Flood Risk Assessment for Draft Carlow County Development Plan 2022-2028 Technical Report July 21 2019s1485 JBA Project Manager Ross Bryant 24 Grove Island Corbally Limerick Ireland Revision History Revision Ref / Date Issued Amendments Issued to S3-P01 - 5 May 2021 Initial version Carlow County Council S3-P02 - 24 May 2021 Updated Carlow County Council A3-C01 - 24 May 2021 Further adjustments Carlow County Council A3-C02 - 8 July 2021 Further adjustments Carlow County Council Contract This report describes work commissioned by Carlow County Council. Carlow County Council’s representative for the contract was Anita Sweeney. Caoimhe Downing and Ross Bryant of JBA Consulting carried out this work. Prepared by .................................................. Caoimhe Downing BEng MSc Assistant Engineer Reviewed by ................................................. Ross Bryant BSc MSc CEnv MCIWEM C.WEM Principal Analyst Purpose This document has been prepared as a Strategic Flood Risk Assessment for Carlow County Council. 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 Carlow County Council. Copyright © JBA Consulting Engineers and Scientists Limited 2021 3a. SFRA i Contents 1 Introduction ............................................................................................................ 1 1.1 Terms of Reference ........................................................................................................... 1 1.2 Report Structure ................................................................................................................. 1 2 Carlow Study Area ................................................................................................. 2 2.1 Planning Policy................................................................................................................... 4 3 The Planning System and Flood Risk Management ............................................. 6 3.1 Introduction ........................................................................................................................ 6 3.2 Definition of Flood Risk ...................................................................................................... 6 3.3 Likelihood of Flooding ........................................................................................................ 6 3.4 Consequences of Flooding ................................................................................................ 7 3.5 Definition of Flood Zones ................................................................................................... 7 3.6 Objectives and Principles of the Planning Guidelines ........................................................ 8 3.7 The Sequential Approach & Justification Test .................................................................... 8 3.8 Scales and Stages of Flood Risk Assessment ................................................................... 9 4 Data Collection and Review .................................................................................. 11 4.1 Overview ............................................................................................................................ 11 4.2 Flood Zone Mapping .......................................................................................................... 16 4.3 Historic Flood Review ........................................................................................................ 16 4.4 Sources of Flooding ........................................................................................................... 19 5 Flood Risk Management Policy ............................................................................. 23 5.1 Surface Water .................................................................................................................... 23 5.2 Flood Risk Management .................................................................................................... 24 6 Development Management and Flood Risk .......................................................... 25 6.1 Requirements for a Flood Risk Assessment ...................................................................... 25 6.2 Drainage Design ................................................................................................................ 25 6.3 Development Proposals in Flood Zone C ........................................................................... 26 6.4 Applications for Developments in Flood Zone A and B ...................................................... 26 6.5 Key points for FRA for all types of developments............................................................... 27 6.6 Incorporating Climate Change into Development Design ................................................... 28 6.7 Flood Mitigation Measures at Site Design .......................................................................... 29 6.8 Green Corridor ................................................................................................................... 31 7 Settlement Zoning Review ..................................................................................... 32 7.1 A Strategic Approach to Flood Risk Management .............................................................. 32 7.2 Ardattin ............................................................................................................................... 34 7.3 Ballinabrannagh ................................................................................................................. 35 7.4 Ballinkillen .......................................................................................................................... 36 7.5 Ballymurphy ....................................................................................................................... 37 7.6 Bennekerry ......................................................................................................................... 39 7.7 Ballon ................................................................................................................................. 41 7.8 Bilboa ................................................................................................................................. 43 7.9 Borris .................................................................................................................................. 44 7.10 Carrickduff .......................................................................................................................... 46 7.11 Carlow ................................................................................................................................ 48 7.12 Clonegal ............................................................................................................................. 50 7.13 Clonmore ........................................................................................................................... 52 7.14 Drumphea .......................................................................................................................... 53 7.15 Garryhill .............................................................................................................................. 54 7.16 Glynn .................................................................................................................................. 55 7.17 Grange ............................................................................................................................... 57 7.18 Fennagh ............................................................................................................................. 58 7.19 Hacketstown....................................................................................................................... 60 7.20 Kildavin .............................................................................................................................. 62 7.21 Leighlinbridge ..................................................................................................................... 64 7.22 Myshall ............................................................................................................................... 66 3a. SFRA Contents 7.23 Newtown ............................................................................................................................ 67 7.24 Newtown Fennagh ............................................................................................................. 68 7.25 Nurney ............................................................................................................................... 69 7.26 Old Leighlin ........................................................................................................................ 70 7.27 Palatine .............................................................................................................................. 72 7.28 Rathanna ........................................................................................................................... 74 7.29 Rathoe ............................................................................................................................... 75 7.30 Rathvilly ............................................................................................................................