Post on 27-May-2020
2 Rogans Court Patrick Street, Dun Laoghaire County Dublin, Ireland Email: info@eireng.ie www.eireng.com
Directors: T. Sheehan, J. Lamb Registered in Ireland Company Registration No. 501522 Tel: +353 (1) 6638957
181307
Omni Living,
Swords Road,
Santry,
D09 C623
Site Specific Flood Risk Assessment
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 2 of 22
Document Control:
Revision Status Date Prepared Checked Approved
PL1 Issued for ABP Pre-Planning 11/10/2019 JC ED JL
PL2 Updated to Pre-Planning Comments 20/03/2020 JC ED JL
PL3 Issued for Planning 23/03/2020 JC ED JL
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 3 of 22
Table of Contents:
1.0 Introduction ................................................................................................................................ 4
2.0 Site Layout and Location ............................................................................................................. 5
2.1 Site Location .................................................................................................................................. 5
3.0 Site Geology ................................................................................................................................ 6
4.0 Flood Risk Identification .............................................................................................................. 7
4.1 Available Flood Studies and Information ...................................................................................... 7
4.2 Historical Flooding (floodmaps.ie) ................................................................................................ 8
4.3 Catchment Flood Risk Assessment and Management Study (CFRAM) (2016) ............................. 8
4.4 Dublin City Development Plan 2016-2022 Strategic Flood Risk Assessment (2016) .................... 9
4.5 FloodResilienCity Project (2012) ................................................................................................. 10
4.6 FloodResilienCity Interim Review October 2011 (2012) ........................................................... 11
4.7 OPW Preliminary Flood Risk Assessment (2011) ........................................................................ 12
4.8 GDSDS Mapping (2005) ............................................................................................................... 12
5.0 Flood Risk Assessment and Mitigation Measures ..................................................................... 14
5.1 Coastal ......................................................................................................................................... 14
5.2 Fluvial .......................................................................................................................................... 14
5.3 Pluvial .......................................................................................................................................... 15
5.4 Groundwater ............................................................................................................................... 15
5.5 Public Sewer ................................................................................................................................ 15
5.6 Flood Risk Summary .................................................................................................................... 16
5.7 Proposed Flood Mitigations Measures ....................................................................................... 16
6.0 Conclusion ................................................................................................................................. 18
Appendix A – Floodmaps.ie Historical Flooding Report........................................................................ 19
Appendix B – Record Drainage Mapping .............................................................................................. 20
Appendix C – Overland Flow Routes ..................................................................................................... 21
Appendix D – Proposed Surface Water Drainage Network .................................................................. 22
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 4 of 22
1.0 Introduction
This report forms part of a Planning Application for a proposed Strategic Housing Development (SHD)
scheme located at Omni Living, Swords Road, Santry, D09 C623.
This report provides an assessment of the subject site for the fluvial, coastal, pluvial, groundwater and
public sewer flood risk for the proposed development.
The layout of the proposed development is detailed in the series of planning drawings by KMD
Architects submitted with this application.
This report should be read in conjunction with EirEng Consulting Engineers drawings.
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 5 of 22
2.0 Site Layout and Location
2.1 Site Location
The location of the proposed development is identified in red in Figure 1 below.
Figure 1 - Subject Site Location
The existing site is located on the Swords Road, Santry, D09 C623. The site is bounded on the north
by an existing industrial estate, on the east by the Swords Road, on the south by an existing petrol
station/fast food outlet and on the west by existing commercial units. The site sits higher than the
adjacent Swords Road which falls away from the site in both the north and south direction.
The proposed development involves the demolition of an existing commercial building and the
construction of three residential apartment blocks, one of which also includes an aparthotel. An
underground basement will provide car parking as well as plant rooms and lifts to service the
development.
Access to the site will be from the existing private industrial road which runs along the northern
boundary of the site. Access for set down areas located on the south of the site will be provided via
the existing Omni Shopping development.
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 6 of 22
Figure 2 - Local Geological Conditions
3.0 Site Geology
Geological Survey Ireland was consulted to determine the geological conditions of the site and the
surrounding area.
The sub-soil on the site is identified as “Made Ground” which would be typical for an urban
environment. The underlying bedrock on the site is identified as dark limestone and shale and part of
the Lucan Formation. The formation comprises of dark-grey to black, fine-grained, micritic limestones
with interbedded dark-grey calcar.
The groundwater vulnerability for the site is classified as low and no karst features are identified within
the surrounding area.
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 7 of 22
4.0 Flood Risk Identification
An assessment of flood risk for the site has been undertaken in accordance with the 2009 DEHLG/OPW
Guidelines on Flood Risk Management.
The objectives are to:
• Identify potential sources of flood risk
• Confirm the level of flood risk and identify key hydraulic features • Assess the impact the proposed development has on flood risk • Develop appropriate flood risk mitigation and management measures which will allow for
the long-term development of the site.
The relevant components to be considered in the identification and assessment of flood risk are as
per Table A1 of the 2009 DEHLG/OPW Guidelines:
• Coastal – flooding from high sea levels
• Fluvial – flooding from water courses
• Pluvial – flooding from rainfall / surface water
• Ground Water – flooding from springs / raised ground water
• Public Sewer – flooding from public sewers
Each component will be investigated and an assessment of the likelihood of a flood occurring will be
undertaken as well as the possible consequences of a flood event.
4.1 Available Flood Studies and Information
The area surrounding the site has been subject to several indicative flood mapping and modelling
studies. The studies examined as part of this flood risk assessment are detailed below:
• Historical Flooding – Floodmaps.ie (1965)
• Catchment Flood Risk Assessment and Management Study (CFRAM) (2016)
• Dublin City Development Plan 2016-2022 PFRA (2016)
• FloodResilienCity Project (2012)
• FloodResilienCity Interim Report October 2011 (2012)
• OPW Preliminary Flood Risk Assessment (2011)
• GDSDS Sewer Flood Maps (2005)
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 8 of 22
Figure 3 Floodmaps.ie Record Flood Events
4.2 Historical Flooding (floodmaps.ie)
Floodmaps.ie was consulted to identify any historical flooding within the vicinity of the site. A flood
event identification node is located adjacent to the site but actually relates to a flood event of the
River Wad in 1965. This event occurred approximately 550m south of the site at the point where the
river is culverted underneath the Swords Road.
The Floodmaps.ie historical report is included in Appendix A.
4.3 Catchment Flood Risk Assessment and Management Study (CFRAM) (2016)
The National CFRAM study involved detailed hydraulic modelling of river bodies and coastal areas and
is the most detailed flood mapping undertaken in the Dublin region. The project commenced in June
2011 with final flood maps issued during 2016.
The CFRAM flood maps do not cover the area of the site and as such do not identify any flood risk for
the site. The nearest available map is located approximately 1km from the site, where limited fluvial
and no coastal flooding is indicated.
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 9 of 22
Figure 4 Santry CFRAMS Flood Mapping (2016)
4.4 Dublin City Development Plan 2016-2022 Strategic Flood Risk Assessment (2016)
The Dublin City Development Plan 2016-2022 Strategic Flood Risk Assessment (SFRA) was prepared
to provide an area-wide assessment of all types of significant flood risk to inform strategic land use
planning decisions. As part of the SFRA a number of predictive flood maps as well as historical
flooding information was analysed to create a composite flood map.
The SFRA flood maps do not cover the area of the site and as such do not identify any flood risk for
the site. The nearest available map is located approximately 1km from the site where limited fluvial
and no coastal flooding, pluvial or groundwater flooding is indicated.
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 10 of 22
Figure 5 Dublin City Development Plan 2016-2022 PFRA (2016)
4.5 FloodResilienCity Project (2012)
As part of a European wide programme, Dublin city was included in a collaboration with other EU
authorities to share knowledge and experience in relation to flood risk.
The main output of the project was a citywide pluvial flood risk map which was developed from a
detailed hydraulic model based on the 180mm (1% AEP) event.
As can be seen in Figure 6 below a portion of the site is identified as having a risk of pluvial flooding.
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 11 of 22
4.6 FloodResilienCity Interim Review October 2011 (2012)
Following on from the FloodResilienCity study a report was commissioned to analyse the fluvial and
pluvial flooding events which occurred across Dublin city due to an extreme rainfall event on the 23rd
and 24th October 2011. These extreme rainfall events have been estimated to be between a 1 in 50
and 1 in 100 year event across the majority of Dublin.
As part of the report a series of detailed maps identifying areas that flooded and their cause was
created. As can be seen in Figure 7 below there was no pluvial or fluvial flooding recorded on or
adjacent to the site during the October 2011 event.
Figure 7 FloodResilientCity Interim Review October 2011 (2012)
Figure 6 FloodResilienCity Pluvial Flood Maps (2012)
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 12 of 22
4.7 OPW Preliminary Flood Risk Assessment (2011)
The OPW Preliminary Flood Risk Assessment (PRFA) was a national screening study which identified
areas that may be at a significant risk associated with flooding. As such it was not a detailed
assessment of flood risk but rather an indicative study with the majority of the fluvial and coastal
information contained within the report since being superseded by the national CFRAM study.
However, the PFRA also contains useful pluvial and groundwater flooding information which was
reviewed as part of this FRA. As can be seen in Figure 8 below there is no pluvial or groundwater
flooding identified on or adjacent to the proposed site.
Figure 8 OPW PFRA (2011)
4.8 GDSDS Mapping (2005)
The Greater Dublin Strategic Drainage Strategy (GDSDS) was completed in 2005 and involved the
mapping and modelling of major sewer lines in the greater Dublin area. From the recommendations
of the report policies were implemented to ensure a consistent approach to drainage infrastructure,
planning, design, construction and operation. As part of the study maps were produced for the future
2031 scenario showing sewer lines at risk of surcharging and flooding.
As can be seen in Figure 9 below the public surface water sewers located in the Swords Road adjacent
to the site were not modelled as part of the study. The nearest public surface water sewers identified
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 13 of 22
on the GDSDS flood maps are located in the adjacent Magenta Hall housing estate and approximately
200m south of the site in the Swords Road. Both public surface water sewers are identified as flooding
less than 5m3 volume for the 5 year return period event, while the downstream 225mm sewer is
identified as flooding for a 30 year return period or less.
Record drainage mapping information is included in Appendix B.
Figure 9 GDSDS Sewer Flooding Maps (2005)
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 14 of 22
5.0 Flood Risk Assessment and Mitigation Measures
5.1 Coastal
As detailed previously the national CFRAM study did not identify any coastal flood risk for the site.
The nearest available map is approximately 1km from the site and identifies no coastal flooding.
Floodmaps.ie was also checked to identify any past coastal flooding events within the vicinity of the
site and none were found.
Based on the above information and given that the Irish Sea lies approximately 6km from the subject
site, and the site level is 56m above sea level the site is considered to be at low risk of coastal flooding.
5.2 Fluvial
The Santry River lies approximately 1km north of the site and the River Wad lies approximately 550m
south of the site.
As detailed previously the national CFRAM study did not identify any fluvial flood risk for the site. The
nearest available map is approximately 1km from the site and identifies limited fluvial flooding from
the Santry River.
As the Santry River is a significant distance from the site and as the site is approximately 10m higher
than the Santry River, it is not considered to pose a flood risk to the site.
Floodmaps.ie was also checked to identify any past fluvial flooding events within the vicinity of the
site. A flood event identification node was found to be located adjacent to the site which related to
an event that occurred in 1965 from the River Wad.
The event occurred approximately 550m south of the site at the point where the river is culverted
underneath the Swords Road. As the event occurred a significant distance from the site and as the
site is approximately 10m higher than the River Wad, it is not considered to pose a flood risk to the
site.
As detailed previously the Dublin City Development Plan SFRA flood maps did not identify any flood
risk for the site. The nearest available map is approximately 1km from the site and identifies limited
fluvial flooding.
The FloodResilienCity Interim Review October 2011 mapping did not identify any fluvial flooding on
the site.
Based on the above information the site is considered to be at low risk of fluvial flooding.
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 15 of 22
5.3 Pluvial
Pluvial flooding is the result of rainfall-generated overland flows which arise before run-off can enter
a watercourse or sewer. It is usually associated with high intensity rainfall and typically occurs in the
summer months.
As detailed previously the FloodResilienCity pluvial flood maps have identified a portion of the site at
risk of pluvial flooding.
It is worth noting that the modelling for the pluvial flood map was based on a relatively broadscale
digital terrain model which did not include small scale (less than 2m2) features, walls or other barriers
to flow and is intended to indicate the potential for pluvial risk.
The FloodResilienCity Interim Review October 2011 mapping did not identify any pluvial flooding on
the site.
Floodmaps.ie was used to identify any past pluvial flooding events within the vicinity of the site and
none were found. There is also no anecdotal evidence of any historic pluvial flooding within the site.
Based on the above information, and primarily on the FloodResilienCity flood maps, the site is
considered to be at risk of pluvial flooding.
5.4 Groundwater
As detailed previously the OPW PRFA flood maps do not identify any groundwater flood risk for the
site.
The GSI groundwater vulnerability classification for the site is low and there are no karst features
located in the area surrounding the site.
Floodmaps.ie was used to identify any past groundwater flooding events within the vicinity of the site
and none were found.
Based on the above information the site is considered to be at low risk of groundwater flooding.
5.5 Public Sewer
As detailed previously GDSDS sewer flood mapping for the area does not cover the public surface
water sewer located in the Swords Road adjacent to the site.
The nearest public surface water sewers identified on the GDSDS flood maps are located in the
adjacent Magenta Hall housing estate and approximately 200m south of the site in the Swords Road.
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 16 of 22
Both public surface water sewers are identified as flooding less than 5m3 volume for the 5 year return
period event, while the downstream 225mm sewer is identified as flooding for a 30 year return period
or less.
The public surface water sewer in the Swords Road mapped as part of the GDSDS is located
approximately 200m south of the site and at a ground level approximately 4m lower than the subject
site.
Given the height difference between the existing public surface water sewers and the proposed
development, and the overland flow paths leading away from the site, the site is considered to be at
low risk of public sewer flooding.
5.6 Flood Risk Summary
Based on the information detailed above the site is considered to be at low risk of flooding from
coastal, fluvial, groundwater and public sewer sources.
The site is considered to be at risk of flooding from pluvial sources.
In accordance with the Department of Environment, Heritage and Local Government and the Office
of Public Work’s jointly published Guidance Document for Planning Authorities - The Planning System
and Flood Risk Management – the site is located within Flood Zone C and no justification test is
required.
As such the proposed development for the site is appropriate for the level of flood risk subject to
mitigation measures being implemented to account for the pluvial flooding risk. The proposed
mitigations measures are detailed in the following section.
5.7 Proposed Flood Mitigations Measures
As detailed previously the site is considered to be at risk of pluvial flooding based on the
FloodResilienCity pluvial flooding maps. The following section details flood risk management
strategies which will be implemented to mitigate the risk of pluvial flooding.
The finished floor level of the proposed development is at a level of 56.400m which provides a
freeboard of between 0.700m – 1.250m above Swords Road. A topographical survey of the site and
surrounding areas including Swords Road was undertaken and it was identified that the site is located
at a high point along Swords Road with the road falling away from the site to the north and to the
south.
Overland flow routes will also be incorporated into the development with any overland flows directed
towards the central landscaping areas located between each apartment block and with a flow pathway
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 17 of 22
provided through the external hardstanding areas of the site. A sketch detailing the overland flow
routes , including existing overland flow routes, is included in Appendix C.
Localised ramping (in accordance with Building Regulations Part M) will provide a threshold of at least
50mm at the entrance to all ground floor doorways to provide protection during extreme rainfall
events.
A surface water drainage system with SUDS features will be incorporated into the development to
positively drain the entire site and to manage surface water run-off from the site. Significant blue and
green sedum roof extents as well as planting and landscaping at surface level will capture the first
flush of intense rainfall events. All surface water flows will be conveyed to a storm water attenuation
tank. The attenuation tank is designed to accommodate the 1 in 100 year flood event plus an
additional 20% for climate change. The outflow from the attenuation tank will be limited to 2 l/s/ha.
A maintenance schedule will be established by the management company for the development to
ensure the surface water drainage network undergoes regular maintenance. The surface water
drainage network will also be inspected after extreme weather events to check for damage and
blockages. The proposed surface water drainage network and SUDS features are detailed on EirEng
drawing 181307-C002 included in Appendix D.
Site access to the development is to be provided from the industrial access road to the north which
links the adjacent industrial/commercial units with Swords Road. The proposed basement access
ramp to the underground car parking area connects into the existing industrial road which runs along
the northern boundary of the site and is located at a high point on the site. The ramp sits outside the
extents of the pluvial flooding shown on the FloodResilienCity maps.
A localised shallow ramp at the access connection point into the existing industrial road will provide a
passive threshold of 100mm to protect the basement from potential overland flow routes from the
existing roadway. This passive protection will consist of a raised footpath crossing the access ramp
entrance which will also have the benefit of providing pedestrian priority. The existing industrial
roadway connects into the Swords Road at a steep gradient and as such falls away from the site at a
significant fall, directing any overland flows onto the Swords Road and away from the site.
The combination of significant freeboard above the Swords Road level, the boundary treatment, the
localised ramping at ground floor entrance doorways to provide a threshold, overland flow routes
directed away from the buildings and a surface water drainage network including attenuation storage
designed to best practice guidelines is considered to be sufficient mitigation measures to provide
protection to the development from the potential pluvial flooding risk.
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 18 of 22
6.0 Conclusion
Having reviewed the available information the site is considered to be at low risk of coastal and fluvial
flooding and therefore in accordance with the Department of Environment, Heritage and Local
Government and the Office of Public Work’s jointly published Guidance Document for Planning
Authorities - The Planning System and Flood Risk Management – is located within Flood Zone C.
The site is also considered to be at low risk of ground water and public sewer flooding.
The site is considered to be a risk of pluvial flooding based on the FloodResilienCity mapping. Several
mitigation measures including significant freeboard above the Swords Road level, the boundary
treatment, the localised ramping at ground floor entrance doorways to provide a threshold, overland
flow routes directed away from the buildings and a surface water drainage network including
attenuation storage designed to best practice guidelines is considered to be sufficient mitigation
measures to provide protection to the development from the potential pluvial flooding risk.
As the site will be positively drained, with the proposed SUDS measures reducing the outflow from
the site to 2 l/s/ha, and as the existing overland flow routes are within the Swords Road falling away
from the site, the proposed development will have no measurable increase on the flood risk to
neighbouring lands.
As a result of the analysis, design and mitigation measures the proposed development is considered
to be in line with the core principles of the Planning Guidelines and Objective outlined in the Dublin
City Development Plan 2016-2022.
Under the Planning Guidelines the site is therefore considered suitable for development of
commercial and residential land uses.
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 19 of 22
Appendix A – Floodmaps.ie Historical Flooding Report
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 20 of 22
Appendix B – Record Drainage Mapping
Legend
dR Unknown Meter ; Other Meter
c Sluice Valve Open
f Sluice Valve Closed
Water Hydrants
Hydrant Function
© Fire Hydrant
±
Cap
! Other Fittings
Water Distribution Mains
Owned By
Irish Water
Private
Irish Water
Sewer Manholes
Manhole Type
! Standard
Gravity - Foul
Storm Manholes
Manhole Type
! Standard
Surface Gravity Mains
1:1,000
Dublin City
SO16398504CL 54.4IL 52.93
SO16397604CL 56.84IL 54.6
SO16397506CL 56.37IL 54.37
SO16397605CL 56.41IL 55.35
SO16398603CL 55.04IL 53.47
SO16397504CL 56.05IL 53.87
SO16397503CL 53.86IL 52.85
SO16397704CL 54.96IL 53.83
SO16398403CL 53.95IL 52.54
SO16397502CL 54.96IL 53.91
SO16397603CL 55.56IL 54.08
SO16398505CL 54.81IL 53.29
SO16397507CL 56.48IL 53.81
SO16398501CL 54.47IL 51.61
SO16397402CL 53.59IL 51.15
SO16397505CL 56.06IL 53.39
SO16398503CL 54.28IL 51.44
SO16397601CL 55.28IL 51.94
SO16398601CL 55.14IL 52.14
SO16398605CL 55.26IL 53.42
SO16397701CL 55.01IL 52.11
225mm Concrete
225m
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4 Unknown 19556 Unknown 1955
4 u
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6 uPVC 1965
150mm uPVC 1989
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150
mm
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6 uPVC 1965
4 uPVC 1965
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150mm uPVC 1989150mm uPVC 1989
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4 uPVC 1965
4 uPVC 1965
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4 uPVC 1965
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Ordnance Survey Ireland 2018
´
1. No part of this drawing may be reproduced or transmitted in any form or stored in any retrievalsystem of any nature without the written permission of Irish Water as copyright holder except asagreed for use on the project for which the document was originally issued.
2. Whilst every care has been taken in its compilation, Irish Water gives this information as to theposition of its underground network as a general guide only on the strict understanding that it is based on the best available information provided by each Local Authority in Ireland to Irish Water. Irish Water can assume no responsibility for and give no guarantees, undertakings or warrantiesconcerning the accuracy, completeness or up to date nature of the information provided and doesnot accept any liability whatsoever arising from any errors or omissions.This information should notbe relied upon in the event of excavations or any other works being carried out in the vicinity of theIrish Water underground network. The onus is on the parties carrying out excavations or any otherworks to ensure the exact location of the Irish Water underground network is identified prior to excavations or any other works being carried out. Service connection pipes are not generally shown but their presence should be anticipated.
© Copyright Irish Water
Reproduced from the Ordnance Survey Of Ireland by Permission of the Government. License No. 3-3-34
a3 - Scale
0 2512.5
Meters
Date: 07/02/2019
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 21 of 22
Appendix C – Overland Flow Routes
ST
AIR
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FF
L +
58.619
FF
L +
59.519
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56.38
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56.40
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56.
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56.40
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falls 1/60
falls 1/60
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6200
PROPOSED SITE
OVERLAND FLOW
ROUTES
EXISTING OVERLAND
FLOW ROUTES
181307 Omni Living, Swords Road, Santry, D09 C623 23-03-20 Site Specific Flood Risk Assessment Page 22 of 22
Appendix D – Proposed Surface Water Drainage Network
STATOIL
McD
ON
ALD
S
Y
IE
L
D
EX
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W
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W
EX
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EXSMH
CL 55.560
IL 54.080
EXSMH
CL 54.980
IL 53.820
EXSMH
CL 56.050
IL 53.870
EXSMH
CL 56.370
IL 54.370
EXSMH
CL 53.960
IL 52.850
EX
-S
W
EX
-S
W
EX
-S
W
EX
-S
W
EX
-S
W
EX
-S
W
EXSMH
CL 56.840
IL 54.600
E
X
-
S
W
E
X
-
S
W
EXSMH
CL 55.520
IL 53.940
EXSMH
CL 55.050
IL 52.700
E
X
-
S
W
E
X
-S
W
E
X
-S
W
EXSMH
CL 55.840
IL 54.340
E
X
-S
W
E
X
-S
W
E
X
-S
W
300Ø
225Ø
X
X
X
X
X
X
X
X
X
X
EX
-SW
EX
-SW
SW
SW
SW
SW
SW
SW
SW
SW
SW
SW
SW
SW
SWMH 1.0
CL - 57.000
IL - 55.530
225Ø
@
1:225
225Ø @1:225
SWMH 2.0
CL - 56.350
IL - 55.230
PROPOSED AQUACELL GEOCELLULAR ATTENUATION TANK OR
SIMILAR APPROVED TO PROVIDE 454m3 OF ATTENUATION STORAGESWMH 11.0
CL - 56.100
IL - 53.350
SWMH 4.1
CL - 56.000
IL - 54.615
SWMH 9.0
CL - 56.200
IL - 54.370
150m
m @
1:150m
m S
LU
NG
150m
m @
1:150m
m S
LU
NG
SWMH5.0
CL - 56.100
IL - 54.472
SWMH6.0
CL - 56.100
IL - 54.425
225m
m
@
1:225m
m
S
LU
NG
SW
S
W
S
W
S
W
S
W
SW
SW
SW
SW
SW
SW
SW
SW
SWMH 3.0
CL - 56.120
IL - 55.191
SWMH 9.1
CL - 56.100
IL - 54.625
SWMH 8.0
CL - 56.200
IL - 54.425
225Ø
@
1:225
3
0
0
Ø
@
1
:2
2
5
IL 53.000
CONNECTION INTO
EXISTING SURFACE WATER
MANHOLE WITH 300mm
BACKDROP CONNECTION
EXISTING MANHOLE TO BE
RECONSTRUCTION AS REQUIRED
TO MATCH NEW INVERT LEVELS
150m
m @
1:150m
m S
LU
NG
150m
m @
1:150m
m S
LU
NG
225m
m @
1:225m
m S
LU
NG
225m
m @
1:225m
m S
LU
NG
225m
m @
1:225m
m S
LU
NG
225m
m @
1:225m
m S
LU
NG
150m
m @
1:150m
m S
LU
NG
SWMH 7.0
CL - 56.100
IL - 54.465
150Ø
@
1:100
SWMH 12.0
CL - 56.100
IL - 53.135
EXISTING PRIVATE
SURFACE WATER
SEWER TO BE MADE
REDUNDANT
SW
EXISTING PRIVATE SURFACE
WATER SEWER TO BE RELAID
ALONG SAME ROUTE AT A
LOWER INVERT LEVEL
150Ø@
1:100
SW
R
G
R
G
SWMH4.0
CL - 56.100
IL - 54.502
N
O
W
A
I
T
I
N
G
I
N
T
H
I
S
A
R
E
A
RWP
RWP
RWP
RWP
RWP
RWP
S
P
R
I
N
K
L
E
R
P
U
M
P
R
O
O
M
EXTENT OF CONCRETE
IN SERVICE CORRIDOR
EXTENT OF TARMAC IN
SERVICE ROAD
S
E
R
V
I
C
E
R
O
A
D
S
P
R
I
N
K
L
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R
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RD
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IC
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A
D
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RV
ICE
YA
RD
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IC
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A
D
TRO
LLEY
S
RWP
SE
RV
IC
E E
NT
RA
NC
E.
UN
IT 1
/2
UN
IT 5
UN
IT 6
UN
IT 7
UN
IT 1
5
UN
IT 1
6
UN
IT 1
7
UN
IT 1
8
UN
IT 1
9
UN
IT 2
0/2
1
UN
IT 2
2
UN
IT 2
3
UN
IT 2
5
UN
IT 2
6
UN
IT 2
7
UN
IT 2
8
UN
IT 2
9
UN
IT 3
0
UN
IT 3
1/3
2
UN
IT 3
3
UN
IT 3
4
UN
IT 3
5
UN
IT 3
6
UN
IT 3
7
UN
IT 3
8
UN
IT 3
9
UN
IT 4
0
UN
IT 4
1
UN
IT 4
2
UN
IT 4
3
UN
IT 4
4
UN
IT 4
5
UN
IT 4
6
UN
IT 4
7
SE
RV
ICE
YA
RD
RE
ST
AU
RA
NT
CE
NT
RA
L P
LA
ZA
UN
IT 4
8
UN
IT 4
9
UN
IT 5
0
SE
RV
IC
E C
OR
RID
OR
4
SE
RV
IC
E
CORRIDOR 6
S
P
R
I
N
K
L
E
R
P
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M
P
R
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S
E
R
V
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C
O
R
R
I
D
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R
7
SERVICE CORRIDO
R 8
SERVICE CORRIDOR 9
S
E
R
V
I
C
E
C
O
R
R
I
D
O
R
1
0
ST
AIR
2
S
T
A
I
R
3
STAIR 4
STAIR 5
S
E
R
V
I
C
E
C
O
R
R
I
D
O
R
1
1
UN
IT 4
8A
R
E
F
R
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G
E
R
A
T
I
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N
R
O
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B
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I
L
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R
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/ UN
IT 5
1
L
I
N
E
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F
M
E
Z
Z
A
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A
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L
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C
.
S
W
I
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C
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R
O
O
M
TOWER 2
RESTAURANT OVER
UN
IT 13 / 14
UN
IT 1
1
UN
IT 1
2
UN
IT
10
DU
CT
DU
CT
DU
CT
H'CAP
PU
BLIC
FEMALE
PU
BLIC
STAFF
FE
MA
LE
STAFF
M
ALE
MALE
ORATO
RY
CRECHE
SERVICE CORRIDO
R 5
/UN
IT 2
4
ST
AIR
7
YA
RD
SE
RV
ICE
S
E
R
V
IC
E
R
O
A
D
UN
IT 8
/9
SERVICE
K1
K2
K3
K4
K5
K6
K7
K8
K9
K10
K11
SE
RV
ICE
YA
RD
ST
OR
E
8823 50432/S
PJS
15 6 92
1:50
PJS
15 6 92
1:50
PR
OT
EC
TE
D C
OR
RID
OR
S
T
A
T
I
O
N
S
U
B
-
U
P
A
.
T
.
M
MA
LL
DE
PA
RT
ME
NT
ST
OR
E
ST
OR
AG
E 5
00 S
Q M
TS
FF
L +
53.2
75
FF
L +
53.2
75
UN
IT 5
3
UN
IT 5
3A
FF
L +
53.2
75
KIOSK UNIT
KIOSK UNIT
7.84 sq.mts
7.84 sq.mts
14A
OF
FIC
E
NE
W M
ALL
MU
LT
I-ST
OR
EY
CA
RP
AR
K
EX
IS
TIN
G
CA
R P
AR
K
LP
FF
L +
59.519
FF
L +
58.619
R=
180.6
mm
G=
250m
m
ST
AIR
S 1
SO
IL &
VE
NT
P
IP
E
SO
IL &
VE
NT
P
IP
E
CO
MP
AC
TO
R
RW
P
UN
IT
4
N.
Dry Riser
Inlet
Dry Riser to
rise to 1st Floor
RW
P
SO
IL &
VE
NT
P
IP
E
2500
EXSMH
CL 55.050
IL 52.700
E
X
-S
W
E
X
-
S
W
E
X
-
S
W
E
X
-
S
W
E
X
-
S
W
E
X
-
S
W
E
X
-
S
W
E
X
-
S
W
E
X
-
S
W
E
X
-
S
W
E
X
-
S
W
EX
-SW
EX
-SW
EX
-SW
EX
-S
W
EX
-S
W
EX
-S
W
EX
-SW
EX
-SW
EX
-SW
E
X
-
S
W
E
X
-
S
W
E
X
-
S
W
E
X
-
S
W
E
X
-
S
W
S
W
FA
ST
FIT
pedestrian lin
k
between U
nit 7
& car parking
100 EXISTING ADJACENT
EXCESS CAR S
PACES
ASSIGNED TO PROPOSED
RETAIL IN SUBJECT
APPLICATION
59 PUBLIC C
AR
PARK SPACES
8242
8233
SWMH 1.0
CL - 57.000
IL - 55.530
EXISTING PRIVATE SURFACE
WATER MANHOLE AND
UPSTREAM OMNI SHOPPING
CENTRE CAR PARK DRAINAGE
NETWORK TO BE RETAINED
EXISTING PRIVATE SURFACE WATER
SEWER TO BE REROUTED AND
RELAID AT A LOWER INVERT LEVEL.
ALL EXISTING CONNECTIONS TO BE
MAINTAINED
SWMH 10.0
CL - 56.000
IL - 53.510
FLOW CONTROL MANHOLE
TO LIMIT OUTFALL FLOW
RATE TO 2.3L/S
General
1. If this drawing has been received electronically it is the
recipients responsibility to print the document to the
correct scale.
2. All dimensions are in (mm.) unless otherwise noted.
3. All levels are in meters above datum unless otherwise
noted.
4. This drawing is to be read in conjunction with all the
relevant Engineers', Services Engineers, Manufacturers
& Architects drawings and specifications.
PROJECT TITLE
DRAWING TITLE
CLIENT
SCALE
DRAWING NUMBERREVISION
STATUS
REVISIONS
REV DATE DESCRIPTIONBY
JOB NO.
DRAWN BY
ENG CHECK
EIRENG CONSULTING ENGINEERS
c
This drawing and any design hereon is the copyright of the Consultants
and must not be reproduced without their written consent. All drawings
remain the property of the Consultants.
Figured dimension only to be taken from this drawing. All
dimensions to be checked on site. Consultants to be informed
immediately of any discrepancies before work proceeds.
DATE
DATE
APPROVED DATE
A1/A3
SHEET
2 Rogan's Court, Patrick Street,Dun Laoghaire, Co.Dublin, Ireland.
Tel: +353 1 6638957 Email: info@eireng.ie
CONSULTING ENGINEERS
I
Aprvd.
OMNI PARK SHOPPING CENTRE
CONSORTIUM
OMNI LIVING, SWORDS ROAD, SANTRY, D09 C623
PROPOSED EXTERNAL SURFACE
WATER AND BASEMENT SLUNG
DRAINAGE LAYOUT
L. Lonergan 26-08-19
J. Cunniffe26-08-19
E. Deasy 26-08-19
PLANNING
181307 C002 PL2
N
E
S
W
EIRENG CONSULT ENG Ltd.ORDNANCE SURVEY IRELANDLICENCE NO. EN0073620 CORDNANCE SURVEY IRELAND
SW
PROPOSED EXTERNAL
SURFACE WATER SEWER
PROPOSED SURFACE
WATER MANHOLE
EX-SW
LEGEND:
PROPOSED SURFACE WATER
SLUNG DRAINAGE PIPE
SWH1.0
SW
EX-SW
EXISTING PUBLIC SURFACE
WATER SEWER
EXISTING PRIVATE SURFACE
WATER SEWER
PROPOSED SEDUM GREEN ROOF
EXTENTS
PROPOSED BLUE ROOF EXTENTS
PROPOSED BUILDING EXTENTS
EXISTING ROAD SURFACE WATER
DRAINAGE NETWORK AND OUTFALL
TO BE RETAINED ALONG PRIVATE
INDUSTRIAL ROAD
PROPOSED BASEMENT OUTLINE
PL1 11.10.19 LL ED PLANNING ISSUE
1:500 A1 - 1:1000 A3
EXISTING PRIVATE SURFACE WATER
SEWER CONTINUES SOUTH THROUGH
OMNI SHOPPING CENTRE DEVELOPMENT
BEFORE CONNECTING INTO AN EXISTING
7500mm DIAMETER PUBLIC SURFACE
WATER SEWER ON SHANLISS ROAD
NOTE:
ALL SURFACE WATER DRAINAGE WITHIN
THE BASEMENT EXTENTS WILL BE SLUNG
AND CONNECT INTO THE PROPOSED
EXTERNAL SURFACE WATER NETWORK
NOTE:
COMBINED BLUE ROOF AREAS WILL
PROVIDE APPROXIMATELY 149m3
OF ATTENUATION STORAGE.
OUTLINE OF
BASEMENT BELOW
OUTLINE OF
BASEMENT BELOW
EXISTING PRIVATE
SURFACE WATER
SEWER
EXISTING PUBLIC
750Ø SURFACE
WATER SEWER
OMNI CENTRE
CARPARK
SURFACE WATER OUTFALL ROUTE
SCALE 1:1000@A1
1:2000@A3
EX SMH
EX-SW
EXISTING PRIVATE SURFACE
WATER SEWER MANHOLE
EXISTING PRIVATE SURFACE
WATER SEWER TO BE REMOVED
EX-SW
EX-SW
XX
EXISTING PUBLIC SURFACE
WATER SEWER MANHOLE
EX SMH
EX SMH
EX SMH
EX SMH
EX SMH
300Ø
375Ø
450Ø
525Ø
5
2
5
Ø
5
2
5
Ø
CONNECTION OF EXISTING PRIVATE
SURFACE WATER SEWER INTO
EXISTING 750mm PUBLIC SEWER
PL2 23.03.20 LL ED PLANNING ISSUE
PROPOSED TRAPPED ROAD
GULLY
RG
SW
1/ ALL DIMENSIONS ARE IN (mm.) UNLESS OTHERWISE NOTED.
CONTRACTOR SHALL BE RESPONSIBLE FOR SETTING OUT JUNCTION BOXES, CHAMBERS,
MANHOLES, GULLIES TO ENSURE NO CLASHES WITH SERVICE DUCTS AND PIPES.
2/ ALL LEVELS ARE IN METRES ABOVE DATUM UNLESS OTHERWISE NOTED.
3/ THIS DRAWING SHOULD BE READ IN CONJUNCTION WITH ALL
RELEVANT ARCHITECT'S, ENGINEER'S AND MANUFACTURERS'
DRAWINGS AND SPECIFICATIONS.
4/ ALL PIPE DIAMETERS ARE NOMINAL.
5/ THE CONTRACTOR MUST CONTACT THE RELEVANT AUTHORITIES
PRIOR TO CONSTRUCTION WORK, AND SATISFY HIMSELF IN
RESPECT TO THE LOCATION OF ALL EXISTING SERVICES.
7/ ALL ROAD GULLY DRAINS ARE 150mm.
8/ 600mm MAX. LENGTH ROCKER PIPES ARE TO BE PROVIDED
ON SEWERS WHERE:
(A). A PIPE ENTERS A MANHOLE OR PUMPING STATION.
(B). A PIPE LEAVES A MANHOLE.
(C). A PIPE ENTERS CONCRETE ENCASEMENT.
(D). A PIPE LEAVES CONCRETE ENCASEMENT.
(E). ANY OTHER LOCATION AS DIRECTED BY THE ENGINEER.
9/ ALL SEWER ROCKER PIPES ARE TO BE FORMED BY CUTTING
AND TRIMMING A LENGTH OF SPIGOT & SOCKET PIPE TO FORM
A SPIGOT AT THE CUT END, THEREBY FORMING SPIGOT & SOCKET
JOINTS AT BOTH ENDS OF THE ROCKER PIPE.
10/ ALL ROCKER PIPES SHALL BE NO MORE THAN 150mm FROM THEIR
ASSOCIATED MANHOLE, PUMPING STATION, CONCRETE ENCASED SECTION
OR VALVE CONNECTION.
11/ WHERE SEWER PIPES, RISING MAINS OR ROAD GULLY DRAINS
CROSS EXISTING ROADS, THE CONTRACTOR IS REQUIRED TO:
(A). CONTACT THE RELEVANT AUTHORITIES PRIOR TO COMMENCING
WORK.
(B). MAKE GOOD THE EXISTING ROAD TO ITS ORIGINAL SPECIFICATION
AS APPROVED BY THE ENGINEER.
(C). UNDERTAKE WORK TO THE STANDARDS OF THE RELEVANT LOCAL AUTHORITY
SPECIFICATION.
16/ CCTV SURVEY TO BE CARRIED OUT ON ALL NEW DRAINAGE RUNS
& CCTV SURVEY INTERPRETIVE REPORT & DRAWINGS TO BE ISSUED TO
ENGINEERS WITH 3No ADDITIONAL COPIES FOR THE LOCAL AUTHORITY
& SAFETY FILE.
17/ ALL COVERS OF EXISTING MANHOLES TO BE BUILT TO FINAL FINISHED
PAVEMENT OR DRAINAGE LEVELS.
18/ COVER LEVELS DETAILED ARE INDICATIVE. COVER LEVELS TO TIE IN
FLUSH WIT PROPOSED PAVEMENT & LANDSCAPING LEVELS.
19/ INTERNAL DRAINAGE TO ARCHITECT & M&E DETAILS
20/ GULLY LAYOUT TO BE CONFIRMED WITH ARCHITECT PRIOR TO DETAILED
DESIGN
21/ RODDING EYES REQUIRED ON ALL SUSPENDED DRAINAGE RUNS AT MAX
22m INTERVALS AND AT ALL JUNCTIONS OR CHANGES IN PIPE DIRECTIONS.
22/ LEVELS ON ALL EXISTING DRAINAGE TO BE CONFIRMED ONSITE.
23/ ALL EXISTING DRAINS TO BE INVESTIGATED FOR LIVE CONNECTIONS PRIOR
TO CONSTRUCTION. LIVE CONNECTIONS TO BE MAINTAINED TO SEWERS
6/ ALL STORMWATER PIPES TO BE POLYPIPE RIGIDRAIN OR SIMILAR APPROVED.
ALL FOUL PIPE TO BE UPVC PIPES BY WAVIN OR SIMILAR APPROVED TO
WIS 4-35-01 and IS EN 13476.
12/ ALL EXISTING FOUL & SURFACE WATER RUNS SERVING THE BUILDING
THAT BECOMES REDUNDANT DUE TO THE NEW DEVELOPMENT TO BE BROKEN
OUT AND TRENCH/MANHOLES TO BE BACKFILLED WITH CL16/20 LEAN MIX CONCRETE
13/ WHERE PIPES PASS UNDER FOUNDATIONS PIPE TRENCH TO BE BACKFILLED TO
FORMATION LEVEL WITH CL16/20 CONCRETE.
14/ WHERE PIPES ARE LOCATED WITHIN 3m OF PAD FOUNDATIONS CONCRETE SURROUND
CL16/20 REQUIRED TO A LEVEL ABOVE THE PAD FOUNDATIONS. WHERE PIPES PASS
UNDER FLOOR SLABS, PIPES TO BE SURROUND WITH 150mm CONCRETE +50mm
COMPRESSIBLE FILL BOARD/SAND SHOULD DIVIDE UNDERSIDE OF SLAB & TOP OF
CONCRETE SURROUND (DETAIL TO BE AGREED WITH STRUCTURAL ENGINEER)
15/ ALL EXISTING MAIN SEWER RUNS TO BE JETTED TO REMOVE BLOCKAGES/DEBRIS, ALL
EXISTING DRAINAGE RUNS & MANHOLES TO BE CLEARED OF DEBRIS, CLEANED, JETTED
AND CCTV CARRIED OUT. INTERPRETIVE REPORT, DVD & DRAWINGS TO BE INCLUDED &
ISSUED TO DESIGN ENGINEER PRIOR TO CONSTRUCTION.
DRAINAGE NOTES
26/ CONTRACTOR TO PROVIDE IL, PIPE DIAMETER AND DIRECTION OF
FLOW IN EXISTING MANHOLE ON COMMENCEMENT OF THE WORKS
TO DESIGN ENGINEER.
24/ ALL SURFACE WATER MANHOLE COVER TO BE SQUARE IN SHAPE.
ALL FOUL WATER MANHOLES TO BE CIRCULAR IN SHAPE.
25/ CONTRACTOR TO COORDINATE ALL ROOF DRAINAGE AND
DOWNPIPES LOCATIONS TO BE AGREED WITH THE ENGINEER AND
ARCHITECT.
27/ ALL SLUNG GRAVITY DRAINAGE PIPEWORK TO WIS 4-35-01 AND IS EN 13476.
28/ PUMPED RISING MAIN TO BE DUCTILE IRON PIPE WORK AND FITTINGS
TO BE IN ACCORDANCE WITH IS EN 598
29/ FOUL SEWER MANHOLES TO BE PRE-CAST, ALL SURFACE WATER
AND COMBINED MANHOLES TO BE BLOCKWORK AS PER GDSDS V6.0
30. ALL MANHOLE COVERS LOCATED IN PAVING AREAS TO BE RECESSED
TYPE WITH GALVINISED STEEL TRIMMING ALLOWING FOR PAVING
INSERTS TO LANDSCAPE ARCHITECTS DETAIL. MANHOLE COVER
LOADINGS TO COMPLY WITH RELEVANT MANHOLE BUILDUP.
31/ ALL DRAINAGE PIPEWORK & MANHOLE CONSTRUCTION TO BE WATERTIGHT
AND ALL MANHOLE LIDS TO BE DOUBLE SEALED. ALL PIPEWORK MUST BE
TESTED TO THE APPROPRIATE AIR TIGHTNESS TEST AND TEST RESULTS
SUBMITTED TO ENGINEER FOR APPROVAL.
SLUNG DRAINAGE, PROPRIETARY CONNECTIONS, SEALING AND FIXINGS
TO BE DESIGNED BY OTHERS TO MANUFACTURERS REQUIREMENTS.
DETAILS TO BE SUBMITTED TO ENGINNER FOR APPROVAL PRIOR TO
WORKS COMMENCING.
NOTE:
IT IS NOT PROPOSED THAT ANY OF THE
PROPOSED SURFACE WATER DRAINAGE
NETWORK WILL BE TAKEN IN CHARGE BY
THE LOCAL AUTHORITY