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Dublin Region Water Services Strategic Plan - 2009 Volume 1/2
DUBLIN REGION WATER SERVICES
STRATEGIC PLAN - 2009
THIS DOCUMENT SUMMARISES THE CURRENT STRATEGIC PLAN IN PLACE FOR THE
DUBLIN REGION AND INCORPORATES THE OUTPUT FROM THE GREATER DUBLIN
STRATEGIC DRAINAGE STUDY AND 1996 WATER SERVICES STRATEGIC PLAN. IT ALSO
INCLUDES THE POLICIES IN THE EXISTING DEVELOPMENT PLANS COVERING WATER
SUPPLY, DRAINAGE AND FLOOD RISK MANAGEMENT.
Dublin Region Water Services Strategic Plan - 2009
TABLE OF CONTENTS (VOLUME 1)
1 INTRODUCTION AND SCOPE OF PLAN................................................................................. 1
1.1 INTRODUCTION ................................................................................................................ 1
1.2 W ATER SERVICES ACT, 2007........................................................................................... 5
1.3 RELEVANT LEGISLATION .................................................................................................. 7
1.4 W ATER SERVICES STRATEGIC PLAN – REPORTS ............................................................... 8
1.5 SCOPE OF W ATER SERVICES STRATEGIC PLAN................................................................. 8
1.6 SYNCHRONISATION WITH OTHER RELEVANT PLANS AND PROGRAMMES ............................. 9
1.6.1 Planning and Development .............................................................................. 9
1.6.2 Water and Environmental Quality Plans .......................................................... 9
1.6.3 Waste Management Plans ............................................................................... 9
2 WATER SUPPLY ..................................................................................................................... 10
2.1 WATER SUPPLY STRATEGIC PLAN - VISION ...................................................................... 10
2.2 W ATER SUPPLY - LEVELS OF SERVICE ............................................................................. 10
2.2.1 Statutory, Customer and Other Levels of Service.......................................... 10
2.2.2 Water Supply - Levels of Service ................................................................... 11
2.3 W ATER SUPPLY STRATEGIC PLAN - OBJECTIVES ............................................................. 12
2.3.1 Quality Objectives .......................................................................................... 12
2.3.2 Capacity Objectives........................................................................................ 13
2.3.3 Asset Management Sustainability Objectives ................................................ 14
2.3.4 Resilient Supply and Operational Flexibility Objectives ................................. 14
2.4 WATER SUPPLY STRATEGIC PLAN – DEMAND ................................................................. 14
2.5 W ATER SUPPLY - STRATEGIC MEASURES ....................................................................... 16
2.5.1 Asset Assessment and Options ..................................................................... 16
2.5.2 Water Services Operations – Strategic Measures ......................................... 17
2.5.3 Water Services Capital Investment – Strategic Measures ............................. 17
2.6 W ATER SUPPLY – WSSP IMPLEMENTATION & INVESTMENT PROGRAMME ........................ 18
3 DRAINAGE .............................................................................................................................. 19
3.1 STRATEGIC DRAINAGE PLAN - VISION .............................................................................. 19
3.2 STRATEGIC DRAINAGE PLAN - LEVELS OF SERVICE ........................................................... 19
3.2.1 Statutory, Customer and Other Levels of Service.......................................... 19
3.2.2 Foul, Combined and Stormwater Drainage.................................................... 19
3.2.3 Foul Sewerage Systems - Levels of Service.................................................. 20
3.2.4 Stormwater System – Levels of Service ........................................................ 24
3.3 STRATEGIC DRAINAGE PLAN - OBJECTIVES ..................................................................... 25
3.4 DRAINAGE - DEMAND FOR WATER SERVICES .................................................................. 26
3.5 DRAINAGE SERVICES – STRATEGIC MEASURES ................................................................ 26
3.5.1 Asset Assessment and Options ..................................................................... 26
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Dublin Region Water Services Strategic Plan - 2009
3.5.2 Foul Drainage Measures ................................................................................ 27
3.5.3 Storm Drainage Measures ............................................................................. 28
3.6 DRAINAGE - PLAN IMPLEMENTATION & INVESTMENT PROGRAMME .................................... 28
4 FLOOD RISK MANAGEMENT ................................................................................................ 30
4.1 FLOOD RISK MANAGEMENT – VISION .............................................................................. 30
4.2 FLOOD RISK IN THE DUBLIN REGION ............................................................................... 30
4.3 FLOOD RISK MANAGEMENT - LEVELS OF SERVICE ............................................................ 32
4.4 FLOOD RISK MANAGEMENT – OBJECTIVES ...................................................................... 33
4.5 FLOOD RISK MANAGEMENT – STRATEGIC MEASURES...................................................... 33
4.6 FLOOD RISK MANAGEMENT - IMPLEMENTATION ............................................................... 35
5 DUBLIN REGION WATER SERVICES STRATEGIC PLAN – DELIVERY ............................ 36
5.1 DELIVERY OF PLAN - CHALLENGES ................................................................................. 36
5.2 DELIVERY OF PLAN - INVESTMENT PROGRAMME .............................................................. 36
6 ENVIRONMENTAL CONSIDERATIONS ................................................................................ 38
6.1 THE W ATER FRAMEWORK DIRECTIVE ............................................................................. 38
6.2 THE SEA DIRECTIVE...................................................................................................... 38
6.3 SUMMARY OF ENVIRONMENTAL CONSIDERATIONS ............................................................ 39
LIST OF FIGURES
Figure 1.1: Greater Dublin Region……………………………………………………………………..………1
Figure 1.2: Greater Dublin Water Supply Area........................................................................................ 3
Figure 1.3: Greater Dublin Strategic Drainage Area ............................................................................... 4
Figure 1.4- Eastern River Basin District .................................................................................................. 6
Figure 1.5 Relevant Legislation ............................................................................................................... 7
Figure 2.1: Future Need Demand Review............................................................................................. 15
Figure 3.2: Foul/ Combined Sewer System........................................................................................... 23
Figure 3.3: Regional Policies –GDSDS................................................................................................. 25
Figure 4.1: Extent of Flooding on the River Dodder, Hurricane Charlie, 1986...................................... 31
Figure 4.2: Dublin Coastal Flooding Protection Project – Project Extent.............................................. 35
APPENDICES (VOLUME 2)
APPENDIX A: DUBLIN REGION WATER SERVICES INVESTMENT PROGRAMMES 2007-
2009
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Dublin Region Water Services Strategic Plan - 2009
1 INTRODUCTION AND SCOPE OF PLAN
1.1 INTRODUCTION
The Water Services Act 2007 provides for the preparation of Water Services Strategic Plans (WSSPs)
by Water Services Authorities and for their review at a minimum every 6 years. The Act provides that,
where appropriate, a number of Water Services Authorities may make a combined Plan for their areas
or parts of their areas where a common approach is required.
In the Dublin Region, the four Dublin Local Authorities (Dublin City Council, Dun Laoghaire-Rathdown,
Fingal and South Dublin County Councils) adopt a co-ordinated approach to the delivery of water
services and this approach also applies to neighbouring areas in Counties Kildare, Meath and Wicklow
(Figure 1.1). It follows that an integrated Dublin Region Water Services Strategic Plan (DR-WSSP) is
appropriate to these areas and services.
Figure 1.1: Greater Dublin Region
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Dublin Region Water Services Strategic Plan - 2009
This document details strategic plans in respect of:-
• Water Supply; where the Dublin Region
Water Supply Area (DRWSA) is defined by
the combined areas served by the Dublin
Region Water Supply Schemes (Figure
1.2), namely,
o Liffey Water Treatment Plants at
Ballymore Eustace (Dublin City
Council) and Leixlip (Fingal County
Council)
o Vartry Plant at Roundwood (Dublin
City Council)
o Dodder Plant at Bohernabreena
(Dublin City Council)
o Bog of the Ring Groundwater
(Fingal County Council).
• Urban Drainage; where the Greater
Dublin Strategic Drainage Area (Figure
1.3) is comprising:
o Ringsend Wastewater Treatment
Works (WwTW) catchment,
including all of Dublin City and
South Dublin, significant parts of
Fingal and Dun Laoghaire-
Rathdown Counties, and an area
in South-East Meath including
Ashbourne, Dunboyne and Clonee
o Fingal County is also served by
WwTWs at Swords, Malahide,
Rush & Lusk, Balbriggan &
Skerries and Portrane;
o Southern Dun Laoghaire
Rathdown County and Bray /
Kilmacanogue in Co. Wicklow are
served by the Shanganagh-Bray
Scheme;
o North and mid-Kildare covered by
the Osberstown and Leixlip
Wastewater Treatment Schemes
• Flood Risk Management; whereby a co-ordinated approach is adopted across the areas
coinciding with the regional drainage catchment, including common policies for development
control and sustainable storm water drainage.
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Dublin Region Water Services Strategic Plan - 2009 Figure 1.2: Greater Dublin Water Supply Area MDW0326Rp0003 3 REV F02
Dublin Region Water Services Strategic Plan - 2009 Figure 1.3: Greater Dublin Strategic Drainage Area MDW0326Rp0003 4 REV F02
Dublin Region Water Services Strategic Plan - 2009
1.2 WATER SERVICES ACT, 2007
The Water Services Act, 2007, provides that each Water Services Authority make a Water Services
Strategic Plan (WSSP) with regard to the provision of water services in its functional area with three
primary objectives;
• Protection of human health and the environment
• Provision of sufficient water services
• Support proper planning and sustainable development.
The major legislative driver for action to improve water quality is the EU Water Framework Directive
(2000/60/EC), being implemented in the Eastern Region (Figure 1.4) by the Eastern River Basin
District (ERBD) Project. This project is developing measures to achieve “good” water quality in its
river, coastal and transitional waters, to be achieved by 2015 at the latest. The River Basin
Management Plans (RBMPs) being developed within the ERBD Project will be reflected in the
WSSPs.
Initially, the WSSP will be developed from available system knowledge, assisted by available technical
studies and having regard to current development policies and plans in the region. Arising from the
adoption of the WSSP, detailed monitoring will improve knowledge of the underlying condition and
performance of water services assets. As a result, periodic reviews of the WSSPs, within a maximum
6 year timeframe, will provide for more detailed “bottom up” assessment of strategic needs to provide;
• Review of actual versus forecast out-turn costs;
• Review of changes in standards and levels of service requirements;
• Review of demand forecasts;
• Prepare revised WSSP for approval.
In the case of the Dublin Region, this draft WSSP is prepared having regard to relevant major studies
undertaken, in particular the following;
• Water Supply; the Greater Dublin Water Supply Strategic Study (GDWSSS 1996 and 2000
Review), including revised assessments carried out in 2006 in the context of the Water Supply
Project- Dublin Region (WSP-DR), the Dublin Water Strategic Storage Study and other technical
studies, detailing the status and priority requirements for water supply across the region
• Urban Drainage; the Greater Dublin Strategic Drainage Study (GDSDS) completed in 2005 which
examined the foul and storm water drainage systems. The GDSDS outlined policies and future
requirements of the region for foul and storm water drainage for the medium to long term. One of
the key strategy recommendations of the GDSDS is the development of a regional wastewater
treatment plant on the Donabate and Portrane peninsula, along with the development of an orbital
sewer to transport wastewater to the regional plant. A Strategic Environmental Assessment (SEA)
on the GDSDS Strategy was completed in 2008, with Fingal County Council as the lead authority
• Flooding; the report of the Flood Policy Review Group (OPW), recommendations from the EU
Funded Strategies and Actions for Flood Emergency and Risk Management (SAFER) Project and
the Dublin Coastal Flooding Protection Project (DCFPP) completed in 2008 and the Catchment
Flood Risk Assessment and Management Studies (CFRAMS) being carried out for the Dodder
and Fingal-East Meath area and the INTERREG IVB Flood Resilien Cities (FRC) Project
addressing the pluvial flooding challenge.
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Dublin Region Water Services Strategic Plan - 2009 Figure 1.4- Eastern River Basin District MDW0326Rp0003 6 REV F02
Dublin Region Water Services Strategic Plan - 2009
1.3 RELEVANT LEGISLATION
The key legislative provisions that specifically relate to water services strategic planning are as
follows;
• The Water Services Act (Act No. 30 of 2007): Sections 36, 37, 38 and 77 of the Act
legislate for the preparation, development, adoption, implementation and continuing review
of water services strategic plans
• The Water Framework Directive (2000/60/EC): established a framework for the protection
of all waters and their dependant wildlife/habitats under one piece of environmental
legislation
• The Planning and Development Act (Act No. 30 of 2000): is a major update and
consolidation of planning and development legislation, which provides for a proper planning
and sustainable development
• Strategic Environmental Assessment Directive (2001/42/EC): requires that the
environmental consequences of certain plans and programmes are identified and assessed
during their preparation and before their adoption. Such plans and programmes are those
that are likely to have significant environmental effects. The relevant arising national
legislation that impacts on water services strategic plans is the European Communities
(Environmental Assessment of Certain Plans and Programmes) Regulations, 2004 (S.I. No.
435 of 2004)
• The EU Floods Directive (2007/60/EC): This Directive requires Member States to assess if
all water courses and coast lines are at risk from flooding, to map the flood extent and
assets and humans at risk in these areas and to take adequate and coordinated measures
to reduce this flood risk.
Figure 1.5 outlines all the relevant legislation provisions at EU and National level that also impact on
water services planning in their requirements that have to be taken into account.
Other Relevant Main Legislation
Legislation
Shellfish
Shellfish Diirective
Diirective Water Services Act 2007
Shellfish Directive
Groundwater Directive
Urban Ww Treatment
Directive
Nitrates Directive Water Framework
Groundwater
Bio DiversityDirective
Groundwater Directives
Directive Directive
Drinking Water Directive
Bathing Water Directive
Water Services
Freshwater Fish Directive Strategic Plans
Water Pollution Acts & Planning & Development
Regs Act 2000
Urban
Urban Ww
Ww Treatment
Treatment
Waste Management Acts
Directive
Directive
Phosphorous
Regulations
Strategic Environmental
Assessment
Figure 1.5 Relevant Legislation
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1.4 WATER SERVICES STRATEGIC PLAN – REPORTS
The Water Services Strategic Plan (WSSP) is
covered in the following hierarchy of reports;
• High Level Executive Summary; summary Executive
statement for regional adoption and Summary
national planning
Strategic Plan
• Dublin Region Local Authorities Water
Services Strategic Plan (this document)-
Detailed plan for management purposes
by local authorities
Technical Reports
• Water Services Strategic Plan – Technical
Background Document; compiled from the
existing technical reports available for the
region, together with review and input from Support Data & Documentation
the individual Local Authority
organisations.
• Support Data & Documentation- Guidance on the Preparation of WSSPs
1.5 SCOPE OF WATER SERVICES STRATEGIC PLAN
In October 2008, Guidance on the Preparation of WSSPs was published by the Water Services
Network Training Group (WSNTG) and the Department of the Environment, Heritage and Local
Government (DEHLG).
For each of the three disciplines, water supply, drainage and flooding, the WSSP is developed under a
number of headings that correspond to the Guidance areas given, as follows:-
• Vision
• Outline Service Standards and Levels of Service
• Objectives
• Demand
• Strategic Measures
• Plan Implementation and Delivery.
These issues are addressed in the WSSP by reference to available reports and system information. A
key requirement of the WSSP would be for monitoring and reporting on system performance, condition
of the assets and security of the service at each review of the WSSP. In this way, the assumptions
would gradually become more robust, the investment needs would be more accurately defined and
investments prioritised and overall service standards improved.
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1.6 SYNCHRONISATION WITH OTHER RELEVANT PLANS AND
PROGRAMMES
Section 36 (6) of the Act identifies the main plans and programmes that water services authorities
should have particular regard to when preparing water services strategic plans (WSSPs). The plans
and programmes to which regard must be given when drafting a WSSP fall under three categories:
1. Planning and Development
2. Water Quality
3. Waste Management
1.6.1 Planning and Development
The relevant plans and strategies in the planning and development area, which should be taken into
consideration, are:
• National Plans and Strategies: Including the National Development Plan and the National
Spatial Strategy
• Regional Plans and Strategies: Including the Regional Planning Guidelines (RPGs) and
Integrated Planning Frameworks
• Local Plans and Strategies: Development Plans.
This DR-WSSP details the current City Plans and projects and is based on the Assessment of Needs
Report adopted by Dublin City Council following public consultation. This infrastructure is necessary to
provide for development of Dublin City as set out in the Development Plan and this document will be
incorporated into the SEA being carried out for the City Development Plan.
As soon as the relevant sections of the Water Services Act 2007 are enacted to prepare a Water
Services Strategic Plan a further SEA will be carried out as required for any additional elements not
included in this current plan.
1.6.2 Water and Environmental Quality Plans
The relevant plans include:
• Water Quality Management Plans
• River Basin District Management Plans and associated Programmes of Measures.
1.6.3 Waste Management Plans
Regard has to be given to the relevant local authority Waste Management Plans and their associated
Sludge Management Plans.
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2 WATER SUPPLY
2.1 WATER SUPPLY STRATEGIC PLAN - VISION
The vision for water supply services in the Dublin Region is:
“To supply adequate drinking water to meet present and future demand in a sustainable
manner to appropriate quality standards to all customers within the region”.
There are three primary objectives to be considered:
• Quality; to meet all of the requirements set out in National
and EU Standards for wholesome safe drinking water
• Quantity; To provide sufficient water to meet domestic and
non-domestic requirements, including allowance for peak
demand at present and into the future
• Sustainability; To be environmentally sustainable such that
demands can be met without compromising “good” water
quality of sources while minimising general environmental
impact.
2.2 WATER SUPPLY - LEVELS OF SERVICE
2.2.1 Statutory, Customer and Other Levels of Service
The principal legislation in Ireland applicable to the delivery of safe drinking water is the European
Communities (Drinking Water) (No. 2) Regulations 2007 - SI No. 278 of 2007. The principal
compliances are that:-
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• Water supplied is wholesome and clean in that it is free from any micro-organisms and
parasites and from any substance in concentrations that constitute a potential danger to
human health
• It meets the microbiological and chemical water quality parametric value standards set out in
the Schedule to the Regulations
• Parameters are to be analysed and minimum frequency of check and audit monitoring for
each supply to be carried out in accordance with provisions in the Schedule to the
Regulations.
While the provision of clean and wholesome water is assured through legislative requirements,
customers also expect a continuous supply at adequate pressures and expect prompt response to
supply interruptions and queries. To ensure customer satisfaction, the following core customer
services standards are identified in the WSSP:-
• Capacity
• Supply Pressure
• Supply Interruptions.
2.2.2 Water Supply - Levels of Service
In developing the WSSP, consideration has been given to current service standards and to good
practice levels of service by reference to international experience. These standards include
fundamental requirements for delivery of quantity and quality but also include reliability of supply,
response time to customer complaints or operational contingency.
The following service standards have been considered in the WSSP together with the levels of service
to be achieved:
• Water Quality; Monitoring indicates that the minimum statutory water quality standards
are generally complied with in the supply. The WSSP requires Local Authorities to aim for
recommended Guideline Standards set out in the Regulations, representing good practice
operating standards, which provide an acceptable margin against failure of mandatory
standards
• Capacity; The WSSP envisages target capacity standards to cater for normal operational
and peak demands. This includes variation over a 24 hour day (morning and afternoon
peaks), seasonal variations and provision for development. As far as practicable, the
system should also meet fire flow requirements while maintaining a basic capacity for
average demand
• Supply Pressure; In general, the WSSP targets a minimum pressure at the supply pipe of
15 metres residual head. It also provides that negative pressures should not occur under
peak conditions as a protection against groundwater entering the network
• Supply Interruptions; Burst rate data is maintained for the network together with other
unplanned interruptions to supply. The age of the network means that a guaranteed
minimum frequency of interruptions would be difficult to achieve in the short term.
However, Local Authorities are using burst rate data to target mains for rehabilitation and
endeavour to provide a minimum response time and maximum outage period, in response
to contingencies causing supply failure. Burst data should be maintained by all Local
Authorities in order to adequately manage supply interruptions.
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These are the basic service standards targeted by the WSSP. Local Authorities also endeavour to
meet good practice standards in terms of response to consumer complaints, advice to consumers on
water conservation and demand management and advice to householders where chronic service pipe
leakage is identified.
The information systems in place across the Dublin Region should be used to evaluate service
performance against these standards on an ongoing basis as demand increases and the system
evolves. The strategic planning function should analyse and evaluate this performance in the
formulation of strategic measures to be implemented.
2.3 WATER SUPPLY STRATEGIC PLAN - OBJECTIVES
Delivery of water to the levels of service identified will require that a number of objectives are satisfied
in respect of the following:
• Water Quality Management (protection of raw water sources)
• Sustainable availability of adequate quantity
• Management of Water Supply Assets
• System Resilience and Operational Flexibility.
2.3.1 Quality Objectives
The management of water quality, for the purposes of meeting drinking water quality standards in a
sustainable manner, requires in the first instance that a holistic catchment based management
approach is taken to protecting water resources, minimising risk of pollution and enforcing appropriate
planning control of development. This requires a coordinated approach between the different local
authorities given that the local authority managing the drinking water facility has little or no control over
the catchment providing the raw water source. This requires that the concept of ‘source to tap’ water
quality management is delivered in terms of:
• Best practice water resource management of the catchments as the primary means of
protecting drinking water quality and reducing risk to public health
• Effective treatment of drinking water at each of the region’s drinking water production
facilities by expanding and operating the facilities in accordance with best practice. This
requires:
o Liffey works at Ballymore Eustace; To complete the upgrading of this plant to
achieve sustainable output of 318Ml/day (at construction stage)
o Liffey works – Leixlip; To upgrade this plant to produce a sustainable
215Ml/day (works at tender stage)
o Vartry works at Roundwood; To complete the refurbishment and maintain
high-quality operation of these works for the maximum sustainable output of
the Vartry source (80Ml/day)
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o Dodder works – Bohernabreena; To complete the refurbishment of these
works and to maintain satisfactory operation for their maximum sustainable
output (18Ml/day)
o Groundwater sources; To continue to develop and protect groundwater
potential in Fingal and Kildare, including monitoring of water quality and water
treatment
• Distribution System; To protect water quality in distribution by an extensive ongoing
monitoring programme and gradual reduction in risk factors in the supply system, in
particular:
o Eliminating uncovered storage in the supply through the provision of covered
reservoirs at Stillorgan and Ballyboden
o Monitoring pressure and avoiding as far as possible low service pressures,
particularly where there is significant leakage risk
o Gradual rehabilitation of old cast-iron mains, lead service pipes and antique
Victorian mains, prioritising areas where monitoring indicates a risk of
pollution to the water, elevated lead or iron concentrations.
• Water Safety Plans; in accordance with the World Health Organisation, will be developed.
2.3.2 Capacity Objectives
The provisions of sustainable quantities of water for present and future needs will be delivered through
the following planned objectives:
• Promoting maximum demand
management and leakage reduction
including pressure management,
leak detection/repairs and priority
mains replacement, allied to
practical measures to promote
demand reduction by consumers
• Completion of upgrading of existing
plants to maximise the sustainable
yield from existing sources. These
works are in tandem with the
upgrading required to ensure
satisfactory water quality
• Strengthening of the distribution network including adequate storage where necessary, to
ensure that adequate capacity can be delivered to all points in the network, including
provision for development needs in accordance with the Local Authority Development
Plans
• Identification and advance planning for new water supply resources for the Dublin Region
to ensure that the medium-to-long term needs of the region can be provided for,
consistent with the National Spatial Strategy and the Water Framework Directive
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2.3.3 Asset Management Sustainability Objectives
Achievement of capacity and quality objectives requires satisfactory performance of the water supply
infrastructure. The WSSP objectives, therefore, include proposals with respect to asset infrastructure:
• To maintain accurate and up-to-date records of system assets and performance, covering
the necessary information required to measure services standards and to identify
deficiencies
• To maintain a programme of asset improvements sufficient to ensure the continued
satisfactory performance including treatment plants, storage reservoirs, trunk and delivery
mains and public supply pipes
• To maintain and update Regional GIS, Regional Telemetry and Regional Water Models to
ensure most up to date data is used
• To provide for effective asset management of water supply infrastructure to include
maintaining up to date information systems (GIS watermains system records) and system
models capable of evaluating capacity and performance. To utilise these systems to
develop asset management plans to maintain satisfactory performance of the assets
• To maintain and upgrade the Regional Telemetry System, facilitating better management
and operation of assets.
2.3.4 Resilient Supply and Operational Flexibility Objectives
The DR-WSSP aims to achieve a level of redundancy within the water supply system whereby an
adequate level of resilience exists to cope with normal operational contingencies. This will be
addressed through:
• Adequacy of treatment capacity to cater for water
source contamination or treatment plant breakdown.
• Adequacy of treated water and supply side storage to
protect against short term interruptions to supply
(system failure, pump or treatment breakdown) and to
meet short term peak demands on the system.
• To be capable of meeting reasonable requirements for
fireflows throughout the network, taking account of the
nature of development and local fire risk categories
and the need to maintain water supply to customers.
2.4 WATER SUPPLY STRATEGIC PLAN – DEMAND
Predicting growth in the demand for water services is based on how demographic, economic and
social factors change in the forthcoming years.
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The Greater Dublin Water Supply Strategic Study (GDWSSS) 1996 contained demand projections for
the period 1996 – 2016. Detailed projections for 2000-2021 were prepared during the subsequent
review of GDWSSS96 in 2000. These projections were updated during the Water Supply Project-
Dublin Region (WSP-DR) Feasibility Study in 2004/5 and again as part of the current WSP-DR
(Preliminary Report) studies in 2007/8.
The process for estimation of future potable water demand for the Dublin Region involved:
• Review of all relevant reports
• Analysis of trends over the 1996 to 2007 period
• Local Authority Consultations.
The total demand is arrived at by consideration of a number of sub-components and preparing
projections for each to arrive at an overall total. The demand sub-components are as follows:
• Domestic Consumption
• Non Domestic Consumption
• Customer Side Leakage
• Distribution Network Leakage
• Headroom (peak/security of supply/contingency/climate change).
Growth in water demand is primarily driven by population increases which result directly in increased
personal consumption and also indirectly in increased industrial / commercial consumption. Economic
growth rates, leakage management performance and water conservation performance are also
contributory factors in demand growth. Average demand in the Dublin Region is expected to increase
from approx 540Mld (2008) to 800Mld (2031). Figure 2.1 summaries demand growth and the Dublin
Regions future needs.
Average Demand Growth Sustainable Production from Existing Source
850
800
Demand Projections
Average Demand
750
New Source Required
700
Ml/d
650
Planned Sustainable Production
600
550
Kildare
(Barrow)
500
450
2003 2005 2007 2009 2011 2013 2015 2017 2019 2021 2023 2025 2027 2029 2031 2033
Year
Figure 2.1: Future Need Demand Review
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Demand figures have been revisited due to the current economic slowdown and the possible effects
on population growth. The overall trend in the forecasting is not thought to be significant. However it
could result in the timeframe for implementing the new water source being extended by one or two
years.
2.5 WATER SUPPLY - STRATEGIC MEASURES
2.5.1 Asset Assessment and Options
In order to plan for the delivery of a water supply, water services authorities shall identify when
infrastructure has to be renewed, replaced or upgraded to meet existing and future customer demands
to the levels of service outlined previously. Asset capacity assessment needs can then be carried out,
i.e. assessing the potable water capacity and any shortfalls in, for example, the:-
o Source and intake
o Raw water mains
o Treatment plants
o Pumping stations
o Trunk/rising mains
o Storage reservoirs
In addition to capacity shortfalls, future changes to legislation relating to water supply (eg. more
stringent drinking water regulations) may generate other shortfalls. Planning for future legislation is
difficult to take account of until such time as the legislation is enacted, whereas higher levels of
customer service expectation can be dealt with through review of the WSSP.
In the case of the Dublin Region, the WSSP is prepared having regard to the aforementioned Greater
Dublin Water Supply Strategic Study (GDWSSS 1996 and 2000 Review), including revised
assessments carried out in 2006 in the context of the ongoing Water Supply Project – Dublin Region
and other technical studies, detailing the status and priority requirements for water supply across the
region.
The options available to deal with asset capacity shortfalls and to deliver the required capacity are
summarised as follows:-
• Adjust current operational practice
of the existing asset
• Rehabilitate or renew the asset
• Upgrade or replace the existing
asset
• Augment the existing capacity to
the required level.
A more detailed methodology on the assessment of assets and identifying options, to solve emerging
shortfalls is given in section 4 of the Guidance on the Preparation of Water Services Strategic Plans,
WSNTG and DEHLG, October 2008.
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2.5.2 Water Services Operations – Strategic Measures
The measures proposed in this WSSP involve a combination of capital and operational steps.
In terms of operations, Water Services Authorities shall provide for the following:
• Effective monitoring and management of water supply operations to verify compliance with
the specified standards of service and progress towards achieving overall objectives of the
WSSP
• Promotion of demand management to encourage best practice water management in new
development and optimum water conservation among existing domestic and non-domestic
users. This involves the provision of information and appropriate technical assistance for
consumers, based on best practice. Pilot projects shall be promoted to target grey water
re-use, use of water saving devices and rainwater recovery reducing water demand by
consumers. Water Conservation Bye-Laws are in place in Dublin City Council, Fingal
County Council and South Dublin County Council
• Maintenance and where necessary upgrading of water conservation and leakage control
systems and resources towards achievement of the medium-term goal of overall regional
water losses of 25% (of water into supply) and long-term 20 year goal (from now) of
achieving a 20% maximum rate of losses across the region
• Promotion of cost effective management of all aspects of the water supply service, from
source to tap, through appropriate input to the Development Planning Process and the
River Basin Management Plans (RBMPs), a representative sampling and analytical
programme, constant review and where appropriate, improvements in the management
and resourcing of water services
• Maintain and upgrade the existing Regional Telemetry, GIS and Network Modelling
Systems.
2.5.3 Water Services Capital Investment – Strategic Measures
Measures involving capital investment are required in accordance with current plans and programmes.
These include:
• Current and planned projects to upgrade water abstraction and treatment, upgrading of
storage, transmission and distribution systems to meet short and medium term supply
needs. This includes projects to upgrade existing treatment, covered reservoir and new
reservoir storage
• Major investment in water mains renewal (€108
million in current contracts) focussed on leakage
reduction as a priority using the most cost-effective
means to upgrade leaking pipes, optimise supply
pressures and reduce unnecessary water use.
There comes a point where reducing leakage below
a certain level (approx 20%) is not economically
viable for networks of this nature – this is known as
the “economic level of leakage” below which
increasing levels of expenditures are required for
ever decreasing leakage reductions
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• Upgrading of Regional Telemetry, GIS and Network Modelling Systems to keep them in
line with modern standards.
In addition to delivering this programme of works targeted at short to medium term needs, the Dublin
Region Water Services Authorities will expedite the planning of new major water resources for the
Dublin Region to meet the long term needs (20 to 25 years and beyond). This involves technical,
environmental and socio-economic assessment of long terms strategic options including possible
abstractions from the River Shannon, in conjunction with dry weather storage options, sea water
abstraction and treatment by desalination and/or measures having regard to development
requirements and climate change. These options are currently being examined through Strategic
Environmental Assessment (SEA).
2.6 WATER SUPPLY – WSSP IMPLEMENTATION & INVESTMENT
PROGRAMME
The delivery of the objectives of the DR-WSSP requires a coordinated approach by the Dublin Region
Water Services Authorities. This is achieved through strategic management and technical
committees, coordinating delivery of capital and operational programmes, subject to the overall
approval of the Department of the Environment, Heritage and Local Government (DEHLG). This
includes:
• Integrated laboratory analysis, flow and pressure measurement and asset management
information systems on behalf of the Authorities in the Region
• Delivery of a capital programme of works estimated to cost approx €500 million during the
lifetime of the WSSP, covering the investment needs for the short to medium term
together with essential planning of long term strategic measures required to meet the
needs beyond the period of the WSSP.
More detailed information on capital expenditure for Water Services within the four Dublin Local
Authorities (Dublin City Council, Dun Laoghaire-Rathdown, Fingal and South Dublin County Councils)
is contained in Section 5 of this WSSP.
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3 DRAINAGE
3.1 STRATEGIC DRAINAGE PLAN - VISION
The vision for drainage services for the Dublin Region is to provide adequate drainage collection and
treatment facilities to meet the present and future demands, while ensuring and maintaining “good
status” of all receiving waters in the Dublin Region into the future.
This is consistent with the objectives of the Water Framework Directive and requires that the
collection, transport and disposal of both foul and stormwater drainage flows are managed effectively
to achieve this purpose.
3.2 STRATEGIC DRAINAGE PLAN - LEVELS OF SERVICE
3.2.1 Statutory, Customer and Other Levels of Service
The principal legislation in Ireland applicable to discharge standards for wastewater schemes is the
Waste Water Discharge (Authorisation) Regulations 2007 – S.I. No. 684 of 2007. Also applicable are
any requirements included in the Programme of Measures within the River Basin Management Plan
for the River Basin to which the waste water scheme discharges – arising from the EU Water
Framework Directive. The compliance requirements will vary depending on the overall impact on, and
the designation of, the water body and the specific requirements of the licensing authority - the
Environmental Protection Agency (EPA).
While the provision is made for the environment with regard
to allowable waste water discharges through legislative
requirements, customers also expect prompt response to
(for example) sewer flooding, environmental concerns and
queries. To ensure customer satisfaction, the following core
customer services standards are identified in the WSSP:-
• Waste Water Treatment Capacity
• Asset Condition
• Sewer Network Capacity/Flooding Risk
• Sewer Infiltration
• Overflows to Receiving Waters
3.2.2 Foul, Combined and Stormwater Drainage
The existing drainage infrastructure comprises foul sewerage infrastructure (Figure 3.1 and Figure
3.2) including pipe network, pumping stations, treatment plants and overflow structures which relieve
overloading in times of heavy rainfall.
In older areas, combined sewers collect both stormwater and foul flows in a common pipe and rely on
combined sewer overflows (CSO’s) to divert excess flows to receiving rivers and streams when the
MDW0326Rp0003 19 REV F02Dublin Region Water Services Strategic Plan - 2009
downstream capacity of the pipe system is exceeded. Where such systems have become overloaded,
there is a potential for pollution at CSO’s.
At treatment plants, foul flows are treated having regard to prescribed effluent standards, while
additional stormwater flows due to rainfall in the first instance overflow to storage for later treatment or
when they exceed the storage capacity discharge directly to receiving waters.
Stormwater drainage provides for the collection of stormwater flows primarily from paved areas (roofs,
roadways, paths etc) and these are generally conveyed to streams, rivers or coastal waters. Such
systems have the potential to collect significant polluting matter which, when discharged, can cause
environmental degradation in the receiving water environment.
3.2.3 Foul Sewerage Systems - Levels of Service
Detailed studies of the existing Dublin region foul sewerage systems have highlighted a number of
difficulties in terms of service standards. These include:
• Quality; all existing treatment plants are undergoing or will require upgrading to provide
adequate capacity for medium term development needs. While most plants are operating
satisfactorily, there is generally a capacity shortfall for projected short term needs and in some
instances tighter effluent standards are required to meet water quality objectives, for example
at Osberstown (Naas). In addition, excessive overflows are occurring in the combined sewer
systems (city and town centres and older urban areas) which result in occasional pollution of
the receiving environment
• Capacity; the foul sewer network modelling has indicated significant surcharge and localised
flood risk on a number of trunk sewers. When additional development is considered in the
models, additional flood risk potential has been identified, generally associated with rainfall
events and associated runoff to the sewer system. In addition, most of the treatment plants will
require capacity upgrading for the additional volumes of sewage arriving at the works, in
addition to treatment of organic and nutrient loadings
• Asset Condition; sewer surveys have identified areas of operational deficiency in the network
in terms of;
- Limited sections of sewers and culverts which are considered structurally deficient.
These can be verified by CCTV surveys and analysis
- Localised blockages and accumulation of sediment debris in foul sewers as identified
by CCTV and hydraulic surveys is prevalent in many areas of the network and reflects
unsatisfactory pipe gradients, artificial obstructions or inadequate maintenance. A
continuing programme of CCTV surveys is required in order to maintain up to date
asset condition records.
Level of service standards have been identified in the GDSDS studies and form the basis of this Water
Services Strategic Plan for foul drainage systems. Key levels of services criteria are:
• Wastewater discharge standards to comply with the requirements
of the Water Framework Directive (WFD) and the specific
requirements of the licensing authorities (EPA)
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• All new non domestic discharges to the foul sewer network to be pre-treated where necessary
to characteristics similar to or less than normal domestic sewage
• For overflows to the receiving water, standards are required to be site specific and involve the
following criteria:
- to provide for a minimum retained flow in the foul sewer to
ensure that any discharges are sufficiently diluted
- to provide a minimum standard of screening to prevent an
aesthetic nuisance (typically 6mm)
- to provide a maximum predicted frequency of spill
appropriate to the receiving waters (for example, 3 times in a
bathing season for bathing waters)
- to provide for appropriate limitations on spill volume and
associated organic and nutrient loadings for discharges to
sensitive waters
• Flooding risk from foul or combined sewers should be extremely low, not less than once in 20
years for on- street flooding and once in 30 years for property flooding
• Maintenance of sewerage systems to avoid excessive silt and debris retention, avoid stagnant
flows and provide for acceptable health and safety conditions for maintenance
• For pumping stations, to ensure appropriate standby equipment, ensure adequate wet well
capacity, control and automation to protect performance in the event of an item of plant failure
and for emergency call-out response in appropriate circumstances.
The information systems in place across the Dublin region should be used to evaluate service
performance against these standards on an ongoing basis as demand increases and the system
evolves. The strategic planning function should analyse and evaluate this performance in the
formulation of strategic measures to be implemented.
MDW0326Rp0003 21 REV F02Dublin Region Water Services Strategic Plan - 2009 Figure 3.1: Existing Foul Sewer Treatment WWTW MDW0326Rp0003 22 REV F02
Dublin Region Water Services Strategic Plan - 2009 Figure 3.2: Foul/ Combined Sewer Systems MDW0326Rp0003 23 REV F02
Dublin Region Water Services Strategic Plan - 2009
3.2.4 Stormwater System – Levels of Service
Stormwater drainage comprises pipe networks, culverts and open channels required to convey runoff
principally from paved areas to local watercourses following rainfall. Historically, such systems were
designed for efficient transfer of rainfall runoff to the receiving environment by the shortest route.
However, they suffer a number of disadvantages:
• As development extends, the rate of runoff from paved areas is generally much greater than
from undeveloped lands with the result that downstream flows increase and flooding can
occur. This phenomenon is evident throughout the network
• Storm drainage systems have often developed in an adhoc fashion, with the result that pipe
and culvert sizes may be inadequate for the ultimate extent of the development. This can give
rise to local obstructions and blockage risks which can increase flooding
• High intensity storm events following a dry spell result in suspension and transport of detritus
and floating debris in pipes, culverts and channels. This gives rise to blockages particularly at
screens or entrances to culverts and bridges, causing flooding. These historic stormwater
systems convey significant polluting matter from streets and other pavements to the
watercourses. As a result, all of the streams in the Dublin conurbation exhibit disimprovement
of quality from undeveloped catchment to developed catchment. This is evident in:
- sediment covering the stream bed, causing loss of ecology
- limited ecological species in the water environment indicative of occasional pollution
shock loadings. This is indicated by the quality “Q” rating system of the EPA whereby
Q1 is highly polluted and Q5 is pristine. In general, urban streams receiving significant
stormwater drainage discharges are Q2 or Q3 at best. These fall well short of the
“good” water quality target set by the Water Framework Directive
- As flows increase, it becomes necessary to upgrade the hydraulic capacity of stream
channels with the result that they are frequently canalised or culverted, with complete
loss of riparian ecology.
In respect of existing storm drainage systems, the criteria for flood risk management are similar to
those applicable to foul sewer systems, namely a minimum of 1 in 20 year protection from street
flooding and 1 in 30 year protection from property flooding. The modelling studies carried out in the
GDSDS study demonstrated local areas at risk throughout the catchments. Site specific risk
assessments are required at these locations to determine the likely risk to property and the
corresponding need for relief measures. In all cases the design criteria should future proof for climate
change and the latest predictions.
The storm sewerage system data is to be accommodated in the same regional information system
(GIS) containing foul sewerage data. The WSSP supports a common database and strategic
evaluation of this information to assess performance and determine priority measures to meet the
objective service standards.
MDW0326Rp0003 24 REV F02Dublin Region Water Services Strategic Plan - 2009
3.3 STRATEGIC DRAINAGE PLAN - OBJECTIVES
The principal objectives for drainage services can be summarised as follows:
• To provide and maintain satisfactory drainage infrastructure having regard to new
development. This requires that drainage system capacity is provided to meet future
development needs while catering satisfactorily for existing load conditions
• To ensure that planning policies are adopted which are consistent with the WSSP. These
policies provide for best practise design, management and operation of drainage services as
developed in the Greater Dublin Strategic Drainage Study (GDSDS) and adopted in the
Development Plans for the Dublin Region Local Authorities (Figure 3.3)
• To provide for effective wastewater treatment for present and future needs, to comply with
requirements of the licensing authorities and in accordance with the water quality criteria set
for the receiving waters. As part of this objective, to provide that new non domestic discharges
(following appropriate treatment at source where necessary) should be at or below the
standard equivalent to domestic sewage
• To provide for sustainable urban drainage systems (SuDs) for all future stormwater drainage
for new development with the objective of ensuring that stormwater discharges from such
developments correspond in respect of both quality and quantity with the equivalent values
from the undeveloped greenfield site
• To provide for effective asset management of drainage infrastructure to include maintaining up
to date information systems (GIS sewerage system records) and system models capable of
evaluating capacity and performance. To utilise these systems to develop asset management
plans to maintain satisfactory performance of the assets
• To maintain and upgrade the Regional Telementry System, facilitating better management
and operation of assets.
New Development
Environmental Management of
SuDS
Receiving Waters
Climate Change
Rising Sea Water Levels
Existing Drainage Infrastructure
Basements
Continuous Discharges
At Risk from
Sewer Flooding Overflows
Inflow / Infiltration / Exfiltration
Figure 3.3: Regional Policies –GDSDS
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3.4 DRAINAGE - DEMAND FOR WATER SERVICES
Predicting growth in the demand for water services is based on how demographic, economic and
social factors change in the forthcoming years.
The GDSDS Final Strategy Report 2005 defined the existing and future drainage requirements of the
Dublin Region using three planning scenarios: years 2001, 2011 and 2031. The 2002 scenario
represented the existing situation during the study, incorporating the 2002 Census results. The 2011
scenario corresponds to the planning horizon of the Regional Planning Guidelines (incorporating the
National Spatial Strategy), which have been reflected by local authorities in their current Development
Plans. The 2031 scenario is a long-term horizon reflecting regional planning policy and drivers.
The GDSDS proposed that the combination of increasing population and decreasing household size
will give rise to a significant increase in numbers of household units in the long term. The increase in
population predicted for the Dublin Region to 2011 has been witnessed over recent years and has
confirmed the urgent need for new drainage infrastructure. The increasing demand places greater
pressure on Dublin’s existing drainage and treatment systems, and in turn has resulted in a drainage
and waste water treatment arrangement in the Dublin Region that is not sustainable.
3.5 DRAINAGE SERVICES – STRATEGIC MEASURES
3.5.1 Asset Assessment and Options
In order to plan for the delivery of a sustainable drainage system, water services authorities shall
identify when infrastructure has to be renewed, replaced or upgraded to meet existing and future
customer demands to the levels of service outlined previously. Asset capacity assessment can then be
carried out, i.e. assessing the drainage network and wastewater treatment capacity and any shortfalls
in, for example, the:-
o Sewers
o Sewer structures
o Sewage pumping stations
o Rising mains
o Waste water treatment plants
o Sea Outfalls
o Sludge Treatment
o Management systems.
In addition to capacity shortfalls, future changes to legislation relating to waste water discharges and
environmental quality of receiving waters may generate other shortfalls. Planning for future legislation
is difficult to plan for until such time as the legislation is enacted, whereas higher levels of customer
service expectation will be dealt with through review of the WSSP.
In the case of the Dublin Region, the DR-WSSP is prepared having regard to the Greater Dublin
Strategic Drainage Study 2005 and other technical studies, detailing the status and priority
requirements for drainage across the region.
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