South Eastern CFRAM Study HA12 Hydraulics Report Wexford Model DOCUMENT CONTROL SHEET
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South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL South Eastern CFRAM Study HA12 Hydraulics Report Wexford Model DOCUMENT CONTROL SHEET Client OPW Project Title South Eastern CFRAM Study Document Title IBE0601Rp0014_HA12 Hydraulics Report Model Name Wexford Rev Status Author(s) Modeller Reviewed by Approved By Office of Origin Issue Date . D01 Draft T.Carberry C.Neill I.Bentley G.Glasgow Limerick/Belfast 23/05/2014 F01 Draft C.Neill C.Neill K.Smart G.Glasgow Belfast Final F02 Draft C.Neill C.Neill K.Smart G.Glasgow Belfast 13/08/2015 Final IBE0601Rp0014 Rev F02 South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL Table of Reference Reports Report Issue Date Report Reference Relevant Section South Eastern CFRAM Study November IBE0601 Rp0001_Flood Risk Review_F01 N/A Flood Risk Review 2011 South Eastern CFRAM Study July 2012 IBE0601Rp0007_HA 11, 12 and 13 4.3.2 Inception Report UoM11, 12 & 13 Inception Report_F02 South Eastern CFRAM Study February IBE0601Rp0012_HA11, 12 & 4.8, 6.2, Hydrology Report UoM11, 12 & 2014 13_Hydrology Report_F02 6.3.2 South Eastern CFRAM Study January IBE0601Rp0016_South Eastern CFRAMS N/A HA11 -17 SC4 Survey Contract 2014 Surv ey Contract Report_F01 4 Hydraulic Model Details.................................................................................................................... 1 4.10 Wexford model......................................................................................................................... 1 4.10.1 General Hydraulic Model Information .............................................................................. 1 4.10.2 Hydraulic Model Schematisation ..................................................................................... 2 4.10.3 Hydraulic Model Construction ........................................................................................ 12 4.10.4 Sensitivity Analysis ........................................................................................................ 26 4.10.5 Hydraulic Model Calibration and Verification ................................................................. 26 4.10.6 Hydraulic Model Assumptions, Limitations and Handover Notes .................................. 48 IBE0601Rp0014 Rev F02 South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL 4 HYDRAULIC MODEL DETAILS 4.10 WEXFORD MODEL 4.10.1 General Hydraulic Model Information (1) Introduction: The South Eastern CFRAM Flood Risk Review report (IBE0601 Rp0001_Flood Risk Review_F01 ) highlighted Wexford in the Slaney catchment as an AFA for coastal and fluvial flooding, along with flooding from mechanism 2 wave overtopping, based on a review of historic flooding and the extents of flood risk determined during the PFRA. The Wexford model is located on the River Slaney as it makes the transition from Upper to Lower Slaney Estuary and on to Wexford Harbour. It is tidally influenced along its length. Additional HPWs directly affecting Wexford AFA are also part of the Wexford model (Model 5). These include: an urban watercourse originating in Hayestown which joins the Slaney at Ferrycarrig Bridge; two small urban watercourses at Carricklawn which enter the Lower Slaney Estuary directly; the Bishops Water which flows through Wexford town and enters the Lower Slaney Estuary; and three small relatively steep watercourses to the south of the AFA at Latimerstown, Sinnottstown and Coolballow. The Sinnotstown watercourse enters Lower Slaney Estuary approximately 1km north of Wexford Harbour. There are no gauging stations with available flow data located on the watercourses within the Wexford model. Gauging station 12064 at Ferrycarrig Bridge is tidal with only water level data available. The total contributing catchment area at the downstream limit of the Slaney portion of the model is 1,753km 2, which includes the entire Slaney catchment. The individual watercourses which directly affect the AFA all have catchment areas of less than 10km 2. There are four models located upstream of the Wexford model – Enniscorthy and Environs (Model 4), Bunclody (Model 3), Tullow (including Tullowphelim) (Model 2) and Baltinglass (Model 1). All watercourses in this model have been identified as high priority watercourses, and so have been modelled as 1D-2D using the MIKE suite of software. (2) Model Reference: HA12_WEXF5 (3) AFAs included in the model: WEXFORD (4) Primary Watercourses / Water Bodies (including local names): Reach ID Name 12SLAN SLANEY 1 12HTWN HAYESTOWN 12LAWN CARRICKLAWN IBE0601Rp0014 4.10-1 Rev F02 South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL 12COTS COOLCOTS 12BISH BISHOPS WATER 12OTTS SINNOTTSTOWN 12LATI SINNOTTSTOWN 12KILN KILEENS 12COOL COOLBALLOW 12SINN SINNOTTSTOWN NORTH (5) Software Type (and version): (a) 1D Domain: (b) 2D Domain: (c) Other model elements: MIKE 11 (2012) MIKE 21 - Flexible Mesh (2012) MIKE FLOOD (2012) 4.10.2 Hydraulic Model Schematisation (1) Map of Model Extents: Figure 4.10.1 and Figure 4.10.2 illustrate the extent of the modelled catchment, river centrelines, HEP locations and AFA extents as applicable. The Wexford model contains one gauging station HEP (12064) at Ferrycarrig Bridge, along with eight Upstream Limit HEPs, five Downstream Limit HEPs, no Intermediate HEPs and seven Tributary HEPs. IBE0601Rp0014 4.10-2 Rev F02 South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL Figure 4.10.1: Map of Model Extents Figure 4.10.2: Map of Model Extents including River Slaney IBE0601Rp0014 4.10-3 Rev F02 South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL (2) x-y Coordinates of River (Upstream Extent): River Name x y 12SLAN SLANEY 1 297791 134684 12HTWN HAYESTOWN 301716 119753 12LAWN CARRICKLAWN 302867 122095 12COTS COOLCOTS 303542 122022 12BISH BISHOPS WATER 302098 119904 12OTTS SINNOTTSTOWN 303330 118653 12LATI 12KILN KILEENS 303067 119488 12COOL COOLBALLOW 304207 118922 12SINN SINNOTTSTOWN NORTH 304122 118260 (3) Total Modelled Watercourse Length: 32.8 km (4) 1D Domain only Watercourse Length: 0 km (5) 1D-2D Domain 32.8 km Watercourse Length: (6) 2D Domain Mesh Type / Resolution / Area: Flexible / 5-160 metres / 126 km 2 (approx.) A smaller mesh size was used in areas of greatly varying topography and adjacent to all 1D-2D connections. Larger cells were used in flatter areas and in the bay area towards the boundary. (7) 2D Domain Model Extent: Figure 4.10.3 and Figure 4.10.4 illustrate the modelled extents and the general topography and bathymetry of the modelled catchment. IBE0601Rp0014 4.10-4 Rev F02 South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL Figure 4.10.3: 2D Domain Model Extent IBE0601Rp0014 4.10-5 Rev F02 South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL Figure 4.10.4: 2D Domain Model Extent - Detail in AFA vicinity Figure 4.10.5 and Figure 4.10.6 illustrate the 1D model cross section and structure locations. Figure 4.10.5 and Figure 4.10.6 below show overview drawings of the model schematisation. Figure 4.10.7 to Figure 4.10.9 show detailed views. The overview diagram covers the model extents, showing the surveyed cross-section locations, AFA boundary and river centre line. It also shows the area covered by the 2D model domain. The detailed areas provided are samples of where there is the most significant risk of flooding. These diagrams include the surveyed cross-section locations, AFA boundary and river centre. They also show the location of the critical structures as discussed in Section 4.10.3, along with the location and extent of the links between the 1D and 2D models. For clarity in viewing cross-section locations, the detailed diagram shows the full extent of the surveyed cross-sections. Note that the 1D model considers only the cross-section between the 1D-2D links. IBE0601Rp0014 4.10-6 Rev F02 South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL Figure 4.10.5: Overview of Model Schematisation (Including River Slaney) Figure 4.10.6: Overview of Model Schematisation IBE0601Rp0014 4.10-7 Rev F02 South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL Figure 4.10.7: Model Schematisation of Coolcots and Carricklawn Rivers Figure 4.10.8: Model Schematisation of Hayestown and Bishops Water Rivers IBE0601Rp0014 4.10-8 Rev F02 South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL Figure 4.10.9: Model Schematisation of Hayestown River Figure 4.10.10 illustrates the extents of the specific 2D domain used during model runs to analyse mechanism 2 wave flooding at the Wexford AFA. There are four distinct ICWWS CAPO Prediction Locations within the Wexford AFA, two of which have been subject to modelling. These are labelled as B and C1/C2 in the diagram (Due to the orientation of the shoreline, for modelling purposes, it was necessary to split Location C into two sections of different lengths, C1 and C2). It should be noted that this mesh is considerably smaller than the overall mesh for analysing fluvial and mechanism 1 tidal flooding as the area of interest is much more localised. IBE0601Rp0014 4.10-9 Rev F02 South Eastern CFRAM Study HA12 Hydraulics Report - DRAFT FINAL B C1 C2 Figure 4.10.10: 2D Domain Model Extent - Wave overtopping (8) Survey Information (a) Survey Folder Structure: First Level Folder Second Level Folder Third Level Folder CCS_S12_M05_12HTWN_Final_WP3_130 12HTWN_Data files 424 South Slobs 12HTWN_Drawings CCS: Surveyor Name 12HTWN_GIS S12: South Eastern CFRAM Study Area, Photos (Naming Hydrometric Area 12 convention is in the M05: Model Number 05 format of Cross-Section 12HTWN: River Reference