Strategic Flood Risk Assessment (SFRA)

Open11 Nov, 2022, 9:00am - 22 Dec, 2022, 12:00pm

Proposed Amendments:


PA SFRA 1: Section 2.2 Coastline and Watercourses, page 4

Amend Section 2.2 (Coastline and Watercourses) of the SFRA as follows:

Fingal CC have provided a GIS shapefile of watercourses within the County as shown in Figure 2.2. The dataset has been compared to EPA watercourse and OPW FSU data and the Fingal CC information has been found to be consistent and more comprehensive than both. However, it is acknowledged that the Fingal CC watercourse dataset is not intended to be exhaustive and does not capture all open waterbodies within the County as there are minor streams and ditches which will not have been captured / included. The mapped watercourses do capture all watercourses with sufficient catchments to be included on Flood Zone datasets (refer to Section 4.2) and as such omission of minor watercourses from the mapped dataset is not a material consideration in terms of establishing flood zones.


PA SFRA 2: Section 2.2.2 Watercourses, page 4

Amend title of Figure 2.2 of the SFRA as follows:

Map of Fingal County Council Watercourse Datas in Fingal


PA SFRA 3: Section 2.2.2.1 List of Watercourses, page 4

Amend Section 2.2.2.1 (List of Watercourses) of the SFRA as follows:

A list of named watercourses in Fingal is provided in Table 2.1. While the list is not exhaustive, it gives an indication of the extent of the river and stream network in the County. Watercourse names are generally as per Environmental Protection Agency (EPA) designations; it is acknowledged that some of the streams listed may be known locally by other names. Watercourse names are shown on flood mapping included as Appendices to the SFRA. It is noted that not all watercourses shown in Figure 2.2 are named so may not be included in Table 2.1 and SFRA flood maps.


PA SFRA 4: Section 2.4 Existing Land Use Zonings, page 7

Amend Chapter 2 (Plan Area), Section 2.4 Existing Land Use Zonings of the SFRA as follows:

The current County Development Plan sets out 21 different land use zonings and zoning objectives, as shown in Table 2.2. The Flood Zone maps included in Appendix A were prepared to assist with future land use zoning decisions in areas that have been assessed as being at risk of flooding.

Land use zoning for the Fingal Development Plan 2023-2029 have been overlain with Flood Zone mapping and Section 5 presents Justification Tests where required.

It is envisaged that an updated set of Zoning Objectives for the Fingal Development Plan 2023 – 2029 will be provided prior to the final version of the SFRA.


PA SFRA 5: Section 4.2 Primary Sources of Flood Risk Information, page 20

Amend Table 4.1 (Sources of Primary Flood Information Summary) of the SFRA as follows:

Information Source

Year Published

Flooding Type

Used for Flood Zone Mapping?

Past Flood Events Mapping

Historical / Ongoing

Various

No

River Tolka Flooding Study

2003

Fluvial

No

Greater Dublin Strategic Drainage Study (GDSDS)

2005

Foul and drainage surface water drainage

Yes (See section 4.2.2) No

Preliminary Flood Risk Assessment (PFRA)

2012

Coastal, fluvial, pluvial, groundwater

Yes

Irish Coastal Protection Strategy Study (ICPSS)

2013

Coastal

No

Fingal East Meath Flood Risk Assessment and Management Study (FEM FRAMS)

2014

Coastal, fluvial

Yes

Catchment Flood Risk Assessment and Management (CFRAM) Study

2015 / 2016

Coastal, fluvial

Yes

GSI Groundwater Flooding

2020

Groundwater

No

National Indicative Fluvial Mapping (NIFM)

2021

Fluvial

Yes

National Coastal Flood Hazard Mapping (NCFHM)

2021

Coastal

Yes

Local Area Plans (LAPs) / Masterplans

Various

Various

Varies
 (see Table 4.5)

River Tolka Flood Study for Fingal CC SFRA (2023-2029)

2022

Fluvial

Yes


PA SFRA 6: Section 4.2.1 Past Flood Event Mapping, page 21

Amend Section 4.2.1 (Past Flood Event Mapping) of the SFRA as follows:

The OPW has recorded and mapped ‘Past Flood Events’ based on available information including flood reports, news articles, photos, Council meeting minutes and other archived information. The record is not an exhaustive record of all flooding that has occurred in Fingal and historic flood events will have occurred that are not captured by this dataset. These records have been reviewed as part of the SFRA along with historic flood event records provided by Fingal CC.


PA SFRA 7: Section 4.2.2 River Tolka Flooding Study, page 22

Amend Section 4.2.2 (River Tolka Flooding Study) of the SFRA as follows:

An updated Flood Study intended to supersede the 2002 study, including new hydrological analysis and hydraulic modelling, has been undertaken to supplement and inform the SFRA and is described in Section 4.2.11. Flood data from the 2002 study therefore is not used for development of Flood Zone mapping as part of this SFRA.

It is noted that strategic level hydraulic modelling of the River Tolka is ongoing and flood extents will supersede the River Tolka Flooding Study at a later stage in the SFRA process.


PA SFRA 8: Section 4.3.7.2 Reservoirs and Dams, page 30

Amend Section 4.3.7.2 (Reservoirs and Dams) of the SFRA as follows:

Potential impounding (storage) reservoirs and service reservoirs either in Fingal or that drain into Fingal were identified using Ordnance Survey Ireland (OSI) mapping and the EPA’s Water Framework Directive dataset of lake segment polygons. Figure 4.3 shows a map of those reservoirs assessed as being potential sources of flood risk in the event of an uncontrolled release of water due to infrastructure failure. Table 4.6 lists these reservoirs in Fingal within the Fingal area.


PA SFRA 9: Section 4.3.7.2 Reservoirs and Dams, page 31

Add title to Figure 4.3 of the SFRA as follows:

Figure 4.3: Map of Reservoirs / Impounded Lakes in Fingal


PA SFRA 10: Section 4.3.7.2 Reservoirs and Dams, page 31

Update Table 4.6 (List of Impounded Lakes / Reservoirs in Fingal) of the SFRA as follows:

ID

Location / Name

Location / Description

Ownership

1

South-west of Garristown

Service reservoir

TBC

2

Naul / Lecklinstown Reservoir and Dam

Impounded Reservoir

TBC

3

Wavin Lakes (south-west of Balbriggan)

Impounded Reservoir

TBC

4

Jordanstown

Service reservoir

TBC

5

Thomastown Service Reservoir

Service reservoir

TBC

6

Portraine Asylum Reservoir and Dam

Impounded Reservoir

TBC

7

Swords Celtic Football Club

Service reservoir

TBC

8

Westereave Lake

Impounded Reservoir

TBC

9

River Santry at Swords Road, Santry Park

Impounded Reservoir

TBC

10

Luttrellstown Golf Course Lakes

Impounded Reservoir

TBC

11

Leixlip Reservoir and Hydro Dam

Impounded Reservoir

TBC

12

Delvin River in Naul

Service reservoir

TBC


PA SFRA 11: Chapter 5 Stage 2 – Initial Flood Risk Assessment and SFRA Maps

Amend Chapter 5 (Stage 2 – Initial Flood Risk Assessment) of the SFRA as follows:

Initial Flood Risk Assessment section to be updated as part of the new Justification Tests for any proposed new zoning, including the overlaying of land zoning and flood zoning. Amend SFRA mapping (mapping sheets 18-21) to include updated Tolka datasets including climate change. Amend mapping sheets 1 – 26 to include all climate change scenarios and improved background mapping detail.


PA SFRA 12: Section 6.6 Drainage and Surface Water Management, page 66

Amend Chapter 6 (Development Management), Section: 6.6 Drainage and Surface Water Management of the SFRA as follows:

All development proposals shall carry out a surface water and drainage assessment and shall be compliant with the following to ensure that drainage from the site is managed sustainably:

  • Department of Housing, Local Government and Heritage ‘Nature Based Solutions to the Management of Rainwater and Surface Water Runoff in Urban Areas, Water Sensitive Urban Design Best Practice Interim Guidance Document’ (2021)
  • Fingal County Council Green / Blue Infrastructure for Development Guidance Note (2021)
  • CIRIA SuDS Manual C753 (2015)
  • Greater Dublin Regional Code of Practice for Drainage Works (2012)
  • Greater Dublin Strategic Drainage Study (GDSDS) (2005)

It is noted that updates to the above documents and / or new published documents during the lifetime of the SFRA are to be implemented as part of Development Management where appropriate.

 

 

 

Submissions

Contents

Home