Climate Change

A Scoping Study to Identify Research Requirements to Assist the UK Water Industry in Dealing with Changing Patterns of Drought

Ref: 00/CL/07/1            Price: £10

ISBN: 1 84057 187 X

The objective of this project was to determine the requirements for future research into the effects of changes in the occurrence of droughts across the whole range of water industry operations. The project was effected through a literature review and discussions with a range of experts and academics in the water industry. Fourteen action areas were identified where research is required.

Land Carbon Sequestration Tool and Tool Guidance Document

Ref: 22/CL/01/31-(1)            Price: £200

ISBN: 978-1-84057-941-3

The key aim of this work is to develop a user-friendly, best practice tool that becomes the UK water industry standard to support strategic carbon sequestration management; forming part of the answer to the UKWIR big question “How do we remove more carbon than we emit by 2050?”.

The project includes development of an industry standard tool for calculating net carbon sequestration across each water company’s land holding and / or the impact of a water company’s work on third party land (for example a catchment partnership project). The tool can be used to create scenarios for different land management strategies so that better decisions can be made regarding carbon emissions and associated land management activities. The tool is aligned with best practice carbon accounting standards and processes.

This report comprises the tool guidance document and the tool. There is a separately available report “Land Carbon Sequestration Tool Development” which details the development of the tool.

Land Carbon Sequestration Tool Development

Ref: 22/CL/01/31            Price: £10

ISBN: 978-1-84057-941-3

The key aim of this work is to develop a user-friendly, best practice tool that becomes the UK water industry standard to support strategic carbon sequestration management; forming part of the answer to the UKWIR big question “How do we remove more carbon than we emit by 2050?”.

The project includes development of an industry standard tool for calculating net carbon sequestration across each water company’s land holding and / or the impact of a water company’s work on third party land (for example a catchment partnership project). The tool can be used to create scenarios for different land management strategies so that better decisions can be made regarding carbon emissions and associated land management activities. The tool is aligned with best practice carbon accounting standards and processes.

This report does not include either the tool guidance document or the tool. There is a separately available report “Land Carbon Sequestration Tool and Tool Guidance Document” which includes the tool.

Renewable Energy in the Water/Wastewater Industries – from current lessons to future contributions

Ref: 15/CL/11/8            Price: £10

ISBN: 1 84057 800 9

Water companies must deliver potable water, treat wastewater, and adhere to quality standards, at a regulated price. There is conflict between these objectives and striving for a low carbon operation.

Whilst water companies can develop renewable energy projects that are considered to be within their regulated business, such as Combined Heat and Power, they are not permitted to develop other projects such as wind energy. Such renewable energy projects could also help maximise efficiency on site and reduce the need for grid electricity.

The aim of this project has been to assist water companies identify and implement renewable energy schemes through the development of a comprehensive techno-financial model to support decision-making, as well as case studies, which will help identify new project opportunities as well as mitigate risks.

Demand Side Energy Management

Ref: 15/CL/11/7            Price: £10

ISBN: 1 84057 782 7

Demand side responses to electricity supply are being incentivised by HM Government and the National Grid to manage restricted grid capacity. UKWIR investigated the potential for demand side energy management in the UK water industry and its challenges and constraints. The principal challenge to water companies in deploying demand side management is that diurnal peak demands for water and electricity coincide.

The UK Water sector needs to proactively pursue and systematically implement value recovery from power use to maximise benefits available. An estimate of benefits of demand management deployment based on interventions in water and wastewater tested in this study produced a sector benefit total of £84million per annum for England and Wales. This opportunity for TOTEX reduction for both water companies and the water sector will require a shift in priorities towards investment in improved flexibility, controllability and energy efficiency to optimise processes and plant.

The Links and Benefits of Water and Energy Efficiency Joint Working - Final Report

Ref: 12/CL/11/6            Price: £10

ISBN: 1 84057 661 8

This project was implemented to i) provide the water industry with firm estimates of the energy efficiency and carbon emission reductions associated with household water efficiency measures; and ii) identify how potential barriers to engagement with other stakeholders involved in promoting energy efficiency could be overcome, optimising benefits and minimising risks for all parties. A literature review identified evidence of measured water, energy and carbon savings associated with water efficiency activities. This evidence was used as the basis for modelling energy and carbon savings from retrofits of the most commonly installed water efficiency devices. Results are presented with confidence limits to reflect uncertainty. A stakeholder engagement exercise obtained feedback on the drivers, barriers and solutions associated with delivering joint water and energy efficiency initiatives. A number of specific recommendations are made based on the study findings that will help enable improved joint delivery of energy and water efficiency programmes.

Energy Efficiency in the Water Industry: A Compendium of Best Practices and Case Studies - Global Report

Ref: 10/CL/11/3            Price: £10

ISBN: 1 84057 571 9

Energy consumption by the water sector has increased considerably as a consequence of the implementation of new technologies to meet tightening potable water and effluent quality standards. The price of energy around the world has also substantially increased.
The objective of this research study was to develop a Compendium of world-wide best practice in the energy efficient design and operation of water industry assets.
The compendium records energy efficiency best practice across a matrix of the water cycle from abstraction, treatment and distribution to sewerage, treatment and disposal. The processes start with conservation and leakage, focus on pumping and aeration, and include sludge treatment. Relevant renewable energy applications are covered to reduce the net energy demand.
Best practices are established through Fact Sheets and illustrated by Case Studies from across the world linked to headings in the matrix. Conclusions on savings and technology are drawn and suggestions are made for future research and development.
The compendium allows easy assimilation of best practice to increase energy efficiency in the water industry for senior management, engineering, operation and maintenance personnel.

Energy Efficiency in the UK Water Industry: A Compendium of Best Practices and Case Studies

Ref: 10/CL/11/2            Price: £10

ISBN: 1 84057 559 X

Over the last decade, energy consumption by the water sector has increased considerably as a consequence of the implementation of new technologies to meet tightening potable water and effluent quality standards. The price of energy has also substantially increased.
The objective of this research study was to develop a Compendium of UK best practice in the energy efficient design and operation of water industry assets.
The compendium records energy efficiency best practice across a matrix of the water cycle from abstraction, treatment and distribution to sewerage, treatment and disposal. The processes start with conservation and leakage, focus on pumping and aeration, and include sludge treatment. Relevant renewable energy applications are covered to reduce the net energy demand.
Best practices are established through Fact Sheets and illustrated by Case Studies from across the UK linked to headings in the matrix. Conclusions on savings and technology are drawn and suggestions are made for future research and development.
The compendium allows easy assimilation of best practice to increase energy efficiency in the water industry for senior management, engineering, operation and maintenance personnel.

Workbook for estimating operational greenhouse gas emissions - version 18

Ref: 24/CL/01/43            Price: £200

ISBN: 978-1-83872-003-2

UKWIR has developed a standardised workbook for estimating operational greenhouse gas emissions, the Carbon Accounting Workbook (CAW), to bring consistency and accuracy to the reporting process across the water industry. The workbook has been in place since 2005 and is updated annually to reflect the needs of the industry, including changes in carbon accounting practices.

This report sets out the changes that have been made in producing version 18 of the CAW. 

The greenhouse gas emissions of nature-based solutions for wastewater treatment

Ref: 24/CL/01/42            Price: £10

ISBN: 978-1-83872-000-1

Using a systematic global literature review, factors were collated that increased or decreased emissions from methane, nitrous oxide and carbon from various typologies of constructed wetland, enhanced septic tank-nature-based solutions (NBS) and stabilisation ponds.  Responses were gathered from water companies, NBS installers and regulators specific to the UK and Irish context, on their interest and monitoring of greenhouse gases (GHGs) in these systems. Most research on this topic has been undertaken in Asia with few published findings for the UK. Most studies compared the GHG emissions from different types of constructed wetland, rather than comparing them to a conventional wastewater treatment plant. No factor was consistent across the three GHGs; what caused a decrease in methane often caused an increase in nitrous oxide, and vice versa. There is a need for long-term monitoring over the lifespans of nature-based wastewater treatment systems combined with consideration of the system’s operation, maintenance and plant-life. 

WWTWs' Process Emissions: Optimisation of Current Processes

Ref: 24/CL/01/41            Price: £10

ISBN: 978-1-84057-999-4

The water industry is committed to reducing its greenhouse gas (GHG) emissions. Through Water UK, the industry published a Net Zero 2030 Routemap. The Scottish Government’s Programme for Government for 2019-20 commits Scotland to net zero by 2045 (in line with the recommendation of the Committee on Climate Change) and includes a specific section on Scottish Water’s commitment to net zero by 2040, including both operational and capital investment GHG emissions. There are similar ambitions and commitments in other parts of the UK. In 2019, the government of Ireland introduced the Climate Action Plan. Irish Water is investigating, with the Irish government, net zero carbon by 2050.

One of the ‘Big Questions’ posed by UKWIR to help inform the strategic programme of research is: How do we remove more carbon than we emit by 2050?  This directly responds to the recent expectations of UK and devolved administrations, and industry commitments. To achieve these, we must develop a better understanding of all GHG emissions.

The first phase of UKWIR’s research on process emissions from WWTWs suggested that they are currently underestimated, particularly in relation to nitrous oxide (N2O). Phase two tested this through UK-based monitoring, and the accumulating evidence is that process emissions are likely the largest part of water sector operational emissions.

This current research project has, therefore, focussed on the practical opportunities to reduce, control, and mitigate nitrous oxide and methane emissions at wastewater treatment works. The report describes the approach taken, including: development and implementation of multi-criteria assessments on more than 400 practical mitigation measures and potential combinations, the creation of a short-list of options, and detailed assessments that consider key criteria under the headings of Overall Sustainability and Ease of Implementation.

Supporting whole life carbon reduction

Ref: 24/CL/01/40            Price: £10

ISBN: 978-1-84057-997-0

There is growing scrutiny of our embodied / scope 3 emissions: the quantum, our management of them, inclusion in business plans and annual reporting. The objectives of this research were to work on particular elements (e.g. emission factors) that sit within the overall framework and to expand our evidence base of wholelife carbon reductions / avoidance achieved in real world cases.

This report has enabled carbon reduction in the water industry to take several steps forward towards achieving rigorous whole life carbon assessments. The rationalisation and consolidation in the meta-database update, coupled with the common supplier protocol and the carbon model templates provide an updated framework to promote greater consistency and transparency in how companies undertake whole life carbon assessments.

Biosolids to land - carbon emissions and carbon capture

Ref: 23/CL/01/38            Price: £10

ISBN: 978-1-84057-979-6

Biosolids recycling to agricultural land is considered the Best Practicable Environmental Option providing a valuable source of nutrients and organic matter.

These nutrients also offset greenhouse gas emissions produced during artificial fertiliser manufacture.

Knowledge of carbon storage and the factors controlling GHG emissions following biosolids recycling to agricultural land is required. Available literature was reviewed to investigate biosolids and to review Emission Factors.

An overview of soil carbon storage was also carried out to: support sustainable use of biosolids: inform water company business plans: review GHG emission factors. An international seminar also allowed intelligence gathering.

Organic material composition of biosolids influence both SOC retention and N2O loss. Soil carbon retention rates appear much lower for biosolids with a high fraction of easily decomposable carbon. Emisssion Factors tended to be low for biosolids with dry matter of >30%, C:N ratio of >12 or <15% of total N as ammonium-N.

Air pollutant emissions across wastewater operations

Ref: 23/CL/01/37            Price: £150

ISBN: 978-1-84057-977-2

The UK government’s 2019 Clean Air Strategy aims to reduce emissions of five of the most damaging air pollutants:  ammonia (NH3), non-methane volatile organic compounds (NMVOCs), nitrogen oxides (NOx), Particulate Matter (PM2.5) and sulphur dioxide (SO2). Wastewater and bioresources treatment have been identified as potential sources of emissions, however, there is little data available to quantify how significant these emissions are. As an initial step towards achieving the Clean Air Strategy, UKWIR commissioned Atkins Ltd to carry out a study to establish the potential sources of the five pollutants and quantify the impact at both a local and national level. This report presents the main findings of this study: quantification of the current emissions associated with wastewater and bioresources treatment; key areas for further investigation; potential mitigation measures and delivery of the first Air Emissions Accounting Workbook.

Workbook for estimating operational GHG emissions – CAW version 17

Ref: 23/CL/01/36            Price: £200

ISBN: 978-1-84057-976-5

UKWIR has developed a standardised workbook for estimating operational greenhouse gas emissions, the Carbon Accounting Workbook (CAW), to bring consistency and accuracy to the reporting process across the water industry. The workbook has been in place for over ten years and is updated annually to reflect the needs of the industry, including changes in carbon accounting practices.

This report sets out the changes that have been made in CAW version 17 (CAW 17).

Implementing Ecosystem Services and Natural and Social Capital Accounting Approaches - Phase 1

Ref: 17/CL/04/15            Price: £10

ISBN: 978-1-84057-894-2

Companies have taken numerous initiatives to better integrate natural and social capital assets into their business planning (e.g. treatment wetlands, payments for ecosystem services, and encouraging pro-environmental behaviours). An Accounting Tool, accompanying guidance document, and project report with two case studies have been developed to support such initiatives. The Tool helps focus on the long-term management of assets and facilitates better investment cases for options that enhance natural and social capital. The Tool produces two outputs: a balance sheet (showing the value of assets and maintenance cost liabilities) and an appraisal summary table (costs and benefits of individual options). The structure and transparency of the Tool respond to the expectations of the (economic and environmental) regulators for more systematic approaches to manage natural and social capital. While for PR19, application could be for pilots, further versions of the Tool can be an integral part of the preparation for PR24.

Implementing Ecosystem Services and Natural & Social Capital Accounting Approaches – Testing & Evaluation

Ref: 20/CL/04/17            Price: £10

ISBN: 978-1-84057-895-9

This project trialled the UKWIR Natural and Social Capital Accounting Tool on case studies with six water companies. The trials helped identify options on the further development of the Tool. The recommended approach is to: provide pre-tool guidance, such as on identifying suitable data; improve functionality, such as tailoring the Tool to different spatial uses; and add extra features, such as space for Defra Biodiversity Metric scores. These improvements to the Tool should be supported by wider communication of the Tool's purpose and function, including through online demonstrations and engagement with regulators and other stakeholders.

The steps and approaches set out in the UKWIR Natural & Social Capital Accounting Tool and associated guidance are consistent with the guidance in the Defra online resource "Enabling a Natural Capital Approach" (ENCA) published in January 2020.

Climate Change Modelling and the WRMP

Ref: 18/CL/04/16            Price: £10

ISBN: 1 84057 862 9

This Guidance reviews current climate change evidence and methodologies and proposes a new approach for WRMP 2024 designed to be used with the forthcoming UKCP18 climate projections. The existing 'top-down' approach to climate change is resource intensive and has led to significant investment to understand how systems respond to different climate exposures. In advance of WRMP 2024, this project has sought to build upon this understanding and has developed a 'bottom-up' approach framed in the context of system resilience to droughts. An online tool accompanies the Guidance to enable practitioners to apply the approach to quickly evaluate new climate change evidence and identify any scenarios for subsequent analysis, where appropriate. Using ten contrasting case studies, the Guidance demonstrates how the approach and tool can be used to assess new climate change evidence in a proportionate, targeted and system specific manner and communicate the results to stakeholders.

Implementing Ecosystem Services and Natural and Social Capital Accounting Approaches - Phase 1

Ref: 17/CL/04/15            Price: £10

ISBN: 978-1-84057-894-2

Companies have taken numerous initiatives to better integrate natural and social capital assets into their business planning (e.g. treatment wetlands, payments for ecosystem services, and encouraging pro-environmental behaviours). An Accounting Tool, accompanying guidance document, and project report with two case studies have been developed to support such initiatives. The Tool helps focus on the long-term management of assets and facilitates better investment cases for options that enhance natural and social capital. The Tool produces two outputs: a balance sheet (showing the value of assets and maintenance cost liabilities) and an appraisal summary table (costs and benefits of individual options). The structure and transparency of the Tool respond to the expectations of the (economic and environmental) regulators for more systematic approaches to manage natural and social capital. While for PR19, application could be for pilots, further versions of the Tool can be an integral part of the preparation for PR24.  

Benefits and limitations of integrating Natural Capital Accounting (NCA) and Ecosystem Services Assessment (ESA) into water company activities

Ref: 16/CL/04/14            Price: £10

ISBN: 1 84057 821 1

This project considers the opportunities and barriers to the introduction of Natural Capital Accounting (NCA) and/or Ecosystem Services Assessment (ESA) into water company business planning. The application of NCA and ESA in the UK is still at a relatively early stage, but it is becoming increasingly prominent as interest increases in the natural capital and ecosystem services which companies draw on. Evidence suggests these approaches are beneficial, though risks and uncertainties remain which have not yet been fully explored.  In order to help the industry, overcome some of these the project outlines a number of recommendations including: further research to provide consistent evidence that allows organisations to decide whether the approaches are right; a programme of engagement with regulatory experts; the development of tools and guidance; and pilot studies to ensure that these approaches work for water companies and that the regulatory community accepts the methods and findings.

Planning for, and Responding to, the Mean and Extremes of Weather - Technical Report

Ref: 15/CL/01/23            Price: £10

ISBN: 1 84057 779 7

This project sought to establish quantifiable links between extreme weather events and their impact on operations and assets in relation to service. Following a series of consultation exercises, literature review and voting, 15 perceived linkages between weather and performance were analysed.

Of the 15 linkages analysed, 13 demonstrated that the hypothesis of weather impacting performance was true, 8 resulted in the development of algorithms and 1 resulted in an algorithm with good predictive potential without further analysis. All linkages would benefit from further analysis with more data (performance and weather), and further investigation into weather-driven and non-weather-related causal factors for the responses.

Correlations have been compared with climate change projections from the latest available science to provide an indication of how the performance in these linkages might change in the future. For one linkage, a worked example has been prepared that illustrates how the predictive model can be used to make estimates of energy costs in the future using the UKCP09 Weather Generator.

Climate Change - A Programme of Research for the UK Water Industry: Volume 2 - Technical Report

Ref: 08/CL/01/8            Price: £10

ISBN: 1 84057 514 X

This report provides a first climate-related snapshot looking across the UK water industry and out to 2100. It identifies where significant uncertainties in the climate science remain, the nature and extent of impact and business risks, adaptation options, and where there are critical knowledge gaps and capactiy within the industry.
A long term, integrated, forward looking programme of climate change research needs is recommended that will allow the industry to put in place a sustrainable response to adapting to climate change and for the industry to develop a 'one voice' approach that will underpin the development of strategies by individaul companies.
The report is in two volumes: a summary report (Volume 1) of the issues and the proposed programme of research needed to meet those issues; and this detailed technical report (Volume 2) which is attached to Volume 1 on CD-ROM.

Impact of Climate Change on Water Demand - Main Report

Ref: 13/CL/04/12            Price: £10

ISBN: 1 84057 684 7

This project assessed the impact of climate change on water demand for use by water companies in their demand forecasts.
Five case studies were analysed to derive relationships between water use and variations in weather. These relationships were then used with UKCP09 climate projections to derive estimates of the impact of climate change on household water demand for each UK River Basin District.
The results suggest that climate change will cause annual average UK household demand to increase by about 0.6% between 2012 and 2040 with largest increases expected in the South of England.
No significant effect was found for non-household demand, except for agriculture and horticulture in the Kent case study.
This report and the accompanying Excel-based look-up tables provide water resources planners with empirical estimates of the impact of climate change for their area, supply the evidence for the predictions, and enable water resources planners to update their 2014 WRMPs.

This report is supplied and sold as a set with 13/CL/04/13 for £500.

Practical Methodologies for Monitoring and Responding to the Impacts of Climate Change on Industry Treatment Processes

Ref: 13/CL/01/20            Price: £10

ISBN: 1 84057 682 0

This study provides companies with a mechanism by which critical climate-sensitive treatment process thresholds may be established, monitored and assessed. As such it facilitates the development of an evidence base from which adaptation actions may be taken that will be justifiable to the regulators and other stakeholders. The study produced a short-list of water and wastewater process thresholds from previous UKWIR projects reported in 11/CL/08/2,3,4 and 12/CL/12/1 respectively, and these were screened for effectiveness and efficiency in terms of monitoring climate impacts. A comparison was made with the typical monitoring that companies already undertake, and recommendations were made for further monitoring both withiin water and wastewater treatment works and the wider catchment (surface waters, collection systems). A process for identifying and attributing trends in threshold exceedance is provided.

Updating the UK Water Industry Climate Change Adaptation Framework - UKWIR Climate Change Adaptation Framework Handbook

Ref: 12/CL/01/18            Price: £10

ISBN: 1 84057 665 0

This project was commissioned to update the previous Water UK framework in order to take account of recent developments in UKWIR projects and other research. The main changes in this updated framework are the greater consideration of the interdependencies, understanding barriers and consideration of climate sensitivities, thresholds and risks and how these may affect levels of service. It aims to provide an over-arching approach to adaptation that is incorporated into more detailed planning and business processes. The framework supports the improvement of resilience and adaptive capacity within water companies.
The main themes of the framework are 'understanding', 'planning' and 'managing'. The activities within these themes take place within an iterative cycle. There are four elements that are relevant across all activities; risks and adaptation actions, adaptive capacity, interdependencies and enablers and barriers.

A Framework for Accounting for Embodied Carbon in Water Industry Assets

Ref: 12/CL/01/15            Price: £10

ISBN: 1 84057 644 8

The purpose of this document is to provide clear and consistent guidelines for UK water companies to: estimate the carbon embodied in constructing and maintaining capital assets using recognised sources of information; carry out 'whole life' carbon accounting for investment selection; and develop strategies for carbon reduction.
The document constitutes an update from previous guidelines in the light of developments in the field. Specifically, (i) the boundaries within which companies should assess their carbon emissions have been changed to match recent Government guidance, (ii) the approaches for embodied carbon and whole life carbon accounting/costing have been revised to support decision-making for low carbon capital investment and (iii) a meta-database of sources of carbon emission factors has been developed to facilitate their common use across the water industry.
Guidance is provided to help companies select accounting boundaries and emission factors expressed in metrics most appropriate to the type of assessment undertaken.

Impact of Climate Change on Asset Management Planning

Ref: 12/CL/01/16            Price: £10

ISBN: 1 84057 625 1

Climate change has the potential to impact asset performance and hence the levels of service provided by the Water Industry. These impacts may significantly affect the capital maintenance or operational expenditure needed to maintain levels of service, mainly because of assets deteriorating at different rates as the long-term mean climate variables change. This project provides a methodology for assessing these impacts and where possible quantifying them. The methodology consists of a sequence of steps for specific mechanisms and asset types. The key concept is that a series of models is needed to establish serviceability or risk change and estimate the funds needed to restore the previous situation - some of these models exist whilst others have yet to be developed.
The report includes a review of literature and consultation with the industry, description of the methodology, and training using four worked examples. Issues identified during development are discussed in detail.

Assessment of the Significance to Water Resource Management Plans of the UK Climate Projections 2009

Ref: 09/CL/04/11            Price: £10

ISBN: 1 84057 547 6

This report provides a 'rapid assessment' of the UK Climate Projections 2009 (UKCP09), published on June 2009, to determine the headline impacts of river flows and any immediate implications for water company Water Resources Plans (WRPs). It builds on previous work published by UKWIR assessing the impacts of climate change based on global climate change models (UKWIR 07/CL/04/10). The study has developed novel methods for using probabalistic information but otherwise uses a similar modelling approach to provide comparative data and an indication of the impacts of probabalistic projections on future rivers flows. Based on this work a number of research recommendations into the use of UKCP09 have been formulated that will form the basis for developing guidelines and methods for use in future Water Resources Plans.

Carbon Accounting in the Water Industry: Non-CO2 Emissions

Ref: 09/CL/01/10            Price: £10

ISBN: 1 84057 532 8

In 2004, UKWIR developed a workbook to support a standardised approach to the quantification of GHG emissions arising from operational activities of UK water companies. Developing the workbook involved selecting GHG estimation methodologies and Emission Factors (EFs). In doing so, it was noted that estimates of non-CO2 emissions were subject to high levels of uncertainty.
This report identities that EFs associated with methane (CH4) and nitrous oxide (N2O) emissions from wastewater and sludge management dominate the overall uncertainty and true values might be up to 3 times higher or lower than the estimate.
It also examines experimental work that is currently ongoing in this field, and estimates the cost of additional experimental work to produce better methodologies/EFs for the most important remaining sources of uncertainty; those research programmes could cost up to £250,000.
The project has identified new EFs relating to sludge which will improve accounting and has highlighted how downstream emissions might be better accommodated. Some changes to the CAW are recommended and these have been implemented in the latest version, Report Ref No 09/CL/01/9.

Climate Change - A Programme of Research for the UK Water Industry: Volume 1 - Summary Report

Ref: 08/CL/01/7            Price: £10

ISBN: 1 84057 513 1

This report provides a first climate-related snapshot looking across the UK water industry and out to 2100. It identifies where significant uncertainties in the climate science remain, the nature and extent of impact and business risks, adaptation options, and where there are critical knowledge gaps and capactiy within the industry.
A long term, integrated, forward looking programme of climate change research needs is recommended that will allow the industry to put in place a sustrainable response to adapting to climate change and for the industry to develop a 'one voice' approach that will underpin the development of strategies by individaul companies.
The report is in two volumes: this summary report (Volume 1) of the issues and the proposed programme of research needed to meet those issues; and a detailed technical report (Volume 2) which is attached to Volume 1 on CD-ROM.

Effect of Climate Change on River Flows and Groundwater Recharge, A Practical Methodology: Synthesis Report

Ref: 07/CL/04/10            Price: £10

ISBN: 1 84057 443 7

This report provides a synthesis of the research outputs of the UKWIR and Environment Agency research project 'Effects of climate change on river flows and groundwater recharge'. A 'Guidelines Report' described a framework and practical methods for use by water companies and the Environment Agency. This 'Synthesis Report' provides an overview of research outputs followed by recommendations for further work to support water companies, 'prepare the ground' for the UKCIP08 scenarios and research studies that continue to improve our understanding of the impacts of climate change on river flows and groundwater recharge.

Effect of Climate Change on River Flows and Groundwater Recharge, A Practical Methodology: Recharge and Groundwater Level Impact Assessment

Ref: 07/CL/04/9            Price: £10

ISBN: 1 84057 439 9

This report provides tools and guidance on how to estimate changes in recharge and regional groundwater levels based on changes in precipitation and potential evaporation.  The report provides a framework for assessing the impacts of climate change on groundwater recharge using three approaches with varying levels of complexity, and provides worked examples of these methods.

In summary these approaches are:
GR1 - Based on a relationship between antecedent precipitation conditions and minimum groundwater levels at a particular location.
GR2 - A spreadsheet model which undertakes lumped calculations of recharge and groundwater level.
GR3 - Utilising existing regional groundwater models.

The methods presented here should enable companies to identify appropriate analytical approaches to assess the impact of climate change. These approaches consider uncertainty and can be used for the PR09 Draft Water Resources Plans.

Effects of Climate Change on River Flows and Groundwater Recharge: Guidelines for Resource Assessment and UKWIR06 Scenarios

Ref: 06/CL/04/8            Price: £10

ISBN: 1 84057 431 3

This report provides technical guidelines for the assessment of the impacts of climate change on average monthly river flows and recharge in UK catchments for the 2020s based on scenarios derived from six Global Climate models. It builds on previous guidance published by UKWIR for 'rapid determination of the effects of climate change', based on the UKCIP02 climate change scenarios and provides a flexible set of methods for considering the impacts of climate change in Water Resources Plans.

Effect of Climate Change on River Flows and Groundwater Recharge, A Practical Methodology: Interim Report on Rainfall-Runoff Modelling

Ref: 06/CL/04/7            Price: £10

ISBN: 1 84057 421 6

This report presents interim results on the impacts of climate change on average monthly river flows and recharge in the UK. It is based on rainfall-runoff modelling of 27 catchments for the 1961-1990 period and for the 2020s and one climate change emissions scenario (A2). This report demonstrates the operation of the methodology for dealing with the uncertainty related to different Global Climate Models (6 GCMs) and hydrological models (2 model structures and large numbers of parameter sets). The modelling results indicate increases in winter flows and reductions in summer flows in the 2020s.

Effect of Climate Change on River Flows and Groundwater Recharge, A Practical Methodology: A Strategy for Evaluating Uncertainty in Assessing the Impacts of Climate Change on Water Resources

Ref: 05/CL/04/6            Price: £10

ISBN: 1 84057 396 1

This report develops a strategy for evaluating uncertainties related to assessing the impacts of climate change on river flows and groundwater recharge. The strategy considers the use of different climate models, hydrological models and methods for translating changes at the global scale to catchment scale changes in river flow and recharge. The approaches discussed in the report are being developed further as part of the on-going research project and will form the basis of a practical framework and 'tool-kit' to help water companies and the Environment Agency assess the potential impacts of climate change.

Climate Change Uncertainty in Water Resource Planning

Ref: 05/CL/04/4            Price: £10

ISBN: 1 84057 389 9

The project investigates uncertainty in the impact of climate change on river flows and water resource. Three sources of uncertainty were considered:

• Uncertainty in climate change projections, due to Global Climate Models (GCM), emission scenarios and downscaling techniques
• Uncertainty in climate variability, including natural variability and reproduction of current climate
• Uncertainty in hydrological modelling, including model parameters and model structure uncertainty

The impact of these uncertainties on the river flow regimes was assessed on thirteen catchments of Britain. Results showed that:

• For the 2020s, uncertainty due to emissions of greenhouse gases is small
• GCM uncertainty is the biggest source of uncertainty. Full impact studies should always consider a range of GCMs
• Downscaling uncertainty is significant but not as great as GCM uncertainty
• Hydrological uncertainty can be significant.

Effect of Climate Change on River Flows and Groundwater Recharge, A Practical Methodology: Trends in UK River Flows 1970-2002

Ref: 05/CL/04/5            Price: £10

ISBN: 1-84057-387-2

Since the late 1980s the UK climate has suffered from a series of dry periods, such as the 1995 drought, and a number of severe floods, such as the flash flooding in Boscastle in August 2004. These events have raised concerns that climate change is causing an increase in the frequency and magnitude of extreme hydrological conditions.

The main objective for this report was to detect trends in river flows for the period 1970 to 2002. The report describes an analysis of 47 river flow records and 10 groundwater observational wells that aimed to detect any early signals of climate change due to changes in the seasonal water balance. Some short to medium term upward trends in autumn and winter river flow were identified but it is not possible, at this stage, to attribute these changes to climate change rather than natural climate variability.

The main benefit of the study is that it provides a framework for the water industry to periodically review trends in river flow and compare these with a range of possible future climate scenarios.

Effect of Climate Change on River Flows and Groundwater Recharge, A Practical Methodology: Use of Climate Change Scenario Data at a Catchment Level

Ref: 05/CL/04/3            Price: £10

ISBN: 1-84057-373-2

This report provides background information on using the United Kingdom Climate Impacts Programme (UKCIP02) climate scenarios (Hulme, et al., 2002) and catchment scale climate scenario data developed as the deliverable from Task 1of  this research project.

An Excel spreadsheet accompanies the report and provides monthly temperature, rainfall and potential evapotranspiration (PET) factors for 190 individual or groups of river catchments in the UK. The catchment boundaries used were Catchment Abstraction Management Strategy (CAMS) areas in England and Wales and Water Framework Directive (WFD) sub-basins in Scotland and Northern Ireland.

The major benefit of the Excel spreadsheet is that it removes the need for individual water resources studies to interpolate the UKCIP02 50km2 data to derive catchment rainfall and PET climate change factors. It also provides a consistent data set that can be used by UK Water Service Providers and Regulators.

Effect of Climate Change on River Flows and Groundwater Recharge UKCIP 02 Scenarios

Ref: 03/CL/04/2            Price: £10

ISBN: 1-84057-286-8

This report presents a procedure for the rapid determination of the effects of climate change by the 2020s on mean monthly runoff and average annual groundwater recharge for strategic scale assessments. The procedure uses three core UKCIP02 scenarios, together with two scenarios characterising the effects of uncertainty and two representing natural climatic variability. Three approaches to translating these scenarios into changes in runoff and recharge are proposed. The report also gives examples of the effect of climate change on Q95, the flow exceeded 95% of the time, for a number of case study catchments.

Effects of Climate Change on River Flows and Groundwater Recharge: Guidelines for Resource Assessment

Ref: 97/CL/04/1            Price: £10

ISBN: 1 84057 010 5

Examines the impacts of four climate scenarios on six climatic regions of the UK. Changes in weather parameters such as rainfall, temperature, potential evaporation are given together with the resulting changes in monthly river flows and in groundwater recharge by the 2020s. The results act as an input to the assessment of reliable yields.

Climate Change Rainfall for use in Sewerage Design - Design Storm Profiles, Antecedent Conditions, Red-Up Tool Update and Seasonality Impacts

Ref: 22/CL/10/19            Price: £250

ISBN: 978-1-84057-956-7

With the first round of the Drainage and Wastewater Management Plans (DWMPs) being produced and increasing industry attention on storm overflows it is important to include the latest climate science in predictions of future rainfall intensities and patterns. This is so that the operators of urban drainage systems can predict and plan for future flooding and pollution risks. The water industry needs updated tools and specific guidance on how to apply this information in readiness for the PR24 planning (in England and Wales) and likely mandatory second cycle DWMPs.

This UKWIR project led by JBA Consulting with Stantec and Newcastle University has developed:

• an updated version of the RED-UP tool, a time series perturbation tool that allows historic rainfall data to be perturbed to be representative of future climate. This version of RED-UP (3.0) supersedes the previous version developed in 2019.
• six experimental new profiles for design rainfall.
• a method of calculating catchment specific future design NAPI values using a climate perturbed rainfall time series together with projected potential evapotranspiration data for the corresponding climate epoch.

Rainfall Intensity for Sewer Design - Technical Guide

Ref: 15/CL/10/16-1            Price: £10

ISBN: 184057 771 1

UK water and sewerage companies do not have a way of assessing the growing risk of customer flooding and pollution from CSOs. Previous research for UKWIR used UKCIP02 and UKCP09 projections and data. However, short-period rainfall statistics used to assess existing and new sewer systems are largely the result of convective rainfall.  Convective rainfall processes are not well simulated by Regional Climate Models (used in UKCP09 and predecessor projections).
Addressing this issue, this project has produced estimates of rainfall intensity change over different parts of the UK using a combination of climate analogue data and a high-resolution (1.5km) climate model developed by the UK Met Office both approaches capturing or resolving convective rainfall events. The resultant rainfall intensity change estimates are, in general, higher than existing UK guidance suggests.

Sewer flooding frequency and volume, and frequency of pollution events are also investigated for five locations; indicating that these are also likely to increase in the future. It is recommended that further work is undertaken to add confidence to the results produced and to inform future UK guidance.

Climate Change Modelling for Sewerage Networks

Ref: 10/CL/10/15            Price: £10

ISBN: 1 84057 573 5

The study provides guidance on incorporating climate change impacts into the modelling of sewerage networks. It is aimed at UK sewerage undertakers and their modelling consultants and is relevant for performance assessments and design.
The report acts as a stand-alone guide for which no detailed knowledge of climate change science is required. It provides a toolkit of approaches based on the use of the UK Climate Projections 2009 (UKCP09) weather generator, guiding the user through its application for including the impact of climate change on extreme rainfall for design storms and timeseries modelling. Twelve example case studies are presented from across the United Kingdom demonstrating the application of the methodology.
Software accompanying the report is provided to facilitate the selection and extraction by the user of data from the UKCP09 Weather Generator.

Climate Change and the Hydraulic Design of Sewerage Systems Volume IV: Associated Topics; IVB - International Drainage Practices

Ref: 03/CL/10/11            Price: £10

ISBN: 1 84057 365 1

This report is part of a major study on the impact of climate change on sewerage hydraulic design The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include, a summary of international drainage practice and predicted changes in sea levels and river flows.

This report is one of 13 documents collated in 4 volumes. This document is one of four in volume IV - Associated Topics.

The other reports in volume IV cover:

• An evaluation of the different parameters used in FSR and FEH and their implications with regard to sewerage system design and simulation
• An overview of high intensity spatial rainfall and the issues relating to climate change and drainage system evaluation

This report provides a summary of current best drainage practices and the possible future direction that drainage design might take is considered.

Climate Change and the Hydraulic Design of Sewerage Systems Volume III: Sewerage System Modelling; IIIC - Changes in River Levels and Flows around the UK

Ref: 03/CL/10/8            Price: £10

ISBN: 1 84057 364 3

This report is part of a major study on the impact of climate change on sewerage hydraulic design The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include a summary of international drainage practice and predicted changes in sea levels and river flows.

This report is one of 13 documents collated in 4 volumes.

This document is one of four in volume III – Sewerage System Modelling.

The other reports in this volume cover:

• Evaluation of the changes in the performance of sewerage systems due to climate change using 5 models of selected drainage systems applied to 4 climate regions
• Use of simple models to evaluate changes in runoff and water quality for 7 climate regions
• A summary of the predicted changes in sea level over the next century

This report summarises the information currently available on the probable changes to river flows over the coming century. It recommends that sensitivity analysis should be applied to sewerage design when the river characteristics are important due to the uncertainty of the flow rate changes. Emphasis is placed on the likely water quality impact due to the prediction of drier summers and reduced flows in rivers.

Climate Change and the Hydraulic Design of Sewerage Systems Volume III: Sewerage System Modelling; IIIB - Changes in Sewerage Run-off and Water Quality

Ref: 03/CL/10/7            Price: £10

ISBN: 1 84057 363 5

This report is part of a major study on the impact of climate change on sewerage hydraulic design The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include a summary of international drainage practice and predicted changes in sea levels and river flows.

This report is one of 13 documents collated in 4 volumes.This document is one of four in volume III - Sewerage System Modelling.

The other reports in volume III cover:

• Evaluation of the changes in the performance of sewerage systems due to climate change using 5 models of selected drainage systems applied to 4 climate regions
• A summary of the predicted changes in river flows over the next century
• A summary of the predicted changes in sea level over the next century

This report documents the use of the time series rainfall data produced for present and future rainfall from 7 sites across the UK to look at the performance of overflow structures (spill frequency and volume) and water quality impact of spills in rivers using simple simulation models. Annual and seasonal runoff was also assessed. The rainfall data was also evaluated and certain modelling parameters quantified.

Climate Change and the Hydraulic Design of Sewerage Systems Volume III: Sewerage System Modelling; IIIA - Changes in the Performance of Sewerage Networks

Ref: 03/CL/10/6            Price: £10

ISBN: 1 84057 362 7

This report is part of a major study on the impact of climate change on sewerage hydraulic design The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include a summary of international drainage practice and predicted changes in sea levels and river flows.This report is one of 13 documents collated in 4 volumes. This document is one of four in volume III - Sewerage System Modelling.  The other reports in volume III cover:Use of simple models to evaluate changes in runoff and water quality for 7 climate regions

• A summary of the predicted changes in sea level over the next century
• A summary of predicted changes to river levels and flows around the UK.

This report summarises the results from using 5 quality assured drainage models run with both present and future rainfall for 4 representative regions across the UK.

The work involved looking at the change in flooding response and the extent of the drainage system modifications needed to return the performance of the systems to their present day performance.  In addition to flooding, the performance of overflows and the change in river water quality were also investigated. The report resulted in a number of suggestions where current practice and criteria might need to be changed.

Climate Change and the Hydraulic Design of Sewerage Systems: Summary Report

Ref: 03/CL/10/0            Price: £10

ISBN: 1 84057 361 9

This report provides an overview of the findings from this major study on the impact of climate change on sewerage hydraulic design. In addition to this Summary Report there are 12 other reports collated in 4 volumes.

The investigations ranged widely, but with a principle focus on the performance of sewerage systems to future (year 2080) rainfall and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include, a summary of international drainage practice and predicted changes in, sea levels and river flows.

The findings of the project as a whole were that, while there are significant uncertainties in the prediction of changes in rainfall over the next century the analysis carried out under this project indicates that for many areas of the UK rainfall events are likely to become more extreme. This would result in a significant reduction in sewerage systems performance particularly in respect of flood protection and CSO discharges and suggests the need for changes in the design of sewerage systems.

A set of national rainfall maps in digital or and paper form have been produced to present the results of the rainfall analysis and illustrate the differences between FSR to FEH and the possible changes to extreme rainfall over the coming century.

Climate Change and the Hydraulic Design of Sewerage Systems Volume IV: Associated Topics; IVC - Spatial High Intensity Rainfall

Ref: 03/CL/10/12            Price: £10

ISBN: 1-84057-346-5

This report is part of a major study on the impact of climate change on sewerage hydraulic design The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include a summary of international drainage practice and predicted changes in sea levels and river flows. This report is one of 13 documents collated in 4 volumes. This document is one of four in volume IV - Associated Topics. The other reports in volume IVcover: - An evaluation of the different parameters used in FSR and FEH and their implications with regard to sewerage system design and simulation - A summary of drainage design practices and the future direction of drainage This report addresses the difficult issue of the limited spatial extent of extreme rainfall and the likely increase of more extreme rainfall events in the future. The report highlights the limitations of current practice in this area.

Climate Change and the Hydraulic Design of Sewerage Systems Volume III: Sewerage System Modelling; IIID Increase in Mean and Extreme Sea Levels around the UK

Ref: 03/CL/10/9            Price: £10

ISBN: 1-84057-345-7

This report is part of a major study on the impact of climate change on sewerage hydraulic design The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include a summary of international drainage practice and predicted changes in sea levels and river flows.

This report is one of 13 documents collated in 4 volumes. This document is one of four in volume III  Sewerage System Modelling. The other reports in volume III cover: 

• Evaluation of the changes in the performance of sewerage systems due to climate change using 5 models of selected drainage systems applied to 4 climate regions
• Use of simple models to evaluate changes in runoff and water quality for 7 climate regions
• A summary of the predicted changes in river flows over the next century.

This report reviews the available information on mean and extreme sea levels around the UK and the potential impacts of climate change on design conditions for sewerage systems.

Climate Change and the Hydraulic Design of Sewerage Systems Volume IV: Associated Topics; IVA - A Comparison between SOIL and HOST; Implications for Urban Drainage Design

Ref: 03/CL/10/10            Price: £10

ISBN: 1-84057-331-7

This report is part of a major study on the impact of climate change on sewerage hydraulic design The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include, a summary of international drainage practice and predicted changes in, sea levels and river flows. This report is one of 13 documents collated in 4 volumes. This document is one of four in volume IV - Associated Topics. The other reports in volume IVcover: - A summary of drainage design practices and the future direction of drainage - An overview of high intensity spatial rainfall and the issues relating to climate change and drainage system evaluation This report addresses the issue of urban runoff models being based on FSR and the implications of the trend to using FEH. Recommendations are made as to how to apply current tools using FEH descriptors. In general this is not seen as causing a major difficulty for sewerage design and simulation tools.

Climate Change and the Hydraulic Design of Sewerage Systems Volume II: Rainfall Data Production & Analysis; IIB - Time-Series Rainfall - Disaggregation

Ref: 03/CL/10/5            Price: £10

ISBN: 1-84057-330-9

This report is part of a major study on the impact of climate change on sewerage hydraulic design The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include a summary of international drainage practice and predicted changes in sea levels and river flows. This report is one of 13 documents collated in 4 volumes. This document is one of two in volume II - Rainfall Data Production & Analysis. The other report in volume II covers: - The development and evaluation of a time series rainfall tool to produce future rainfall using data from the Hadley model. 100 years of present and future data were produced for 7 regions across the UK. This report covers the work carried out on developing a tool (Cascade) for use in producing high resolution rainfall data from a time series. This tool uses various measures of rainfall characteristics to produce representative rainfall through the seasons. The tool was compared favourably to StormPac which is the only available tool currently available on the market.

Climate Change and the Hydraulic Design of Sewerage Systems Volume II: Rainfall Data Production & Analysis; IIA - Time-Series and Design Event Update

Ref: 03/CL/10/4            Price: £10

ISBN: 1-84057-329-5

This report is part of a major study on the impact of climate change on sewerage hydraulic design The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include a summary of international drainage practice and predicted changes in sea levels and river flows. This report is one of 13 documents collated in 4 volumes. This document is one of two in volume II - Rainfall Data Production & Analysis. The other report in volume II covers: - The development and evaluation of a disaggregation tool to produce high resolution data from an hourly or other coarser resolution series. This report covers the work carried out on developing a tool (Balerep) for use in generating future rainfall. 100 year time series data output was generated for the present day and 2080 - 2100 Medium-High scenario. Seasonal characteristics of rainfall were considered important to be represented accurately. The use of design storms and the profile to be used for future rainfall is also covered.

Climate Change and the Hydraulic Design of Sewerage Systems Volume I: Climate Change Effects on Rainfall; IC - Seasonality Study

Ref: 03/CL/10/3            Price: £10

ISBN: 1-84057-328-7

This report is part of a major study on the impact of climate change on sewerage hydraulic design The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include, a summary of international drainage practice and predicted changes in sea levels and river flows. This report is one of 13 documents collated in 4 volumes. This document is one of three in volume I - Climate Change Effects on Rainfall. The other reports in volume I cover: - A sensitivity analysis of the differences between the predictions of the UKCIP98 models and the UKCIP02 models. - A report summarising the work carried out by the Met Office in producing predictions for extreme rainfall of the future based on the UKCIP98 Medium-High Scenario and the production of present day and future rainfall maps. Comparison of rainfall from FSR and FEH methods was also carried out. This report extends the work carried out comparing the UKCIP98 and UKCIP02 rainfall data breaking the information down into seasons. This was needed due to the major differences in seasonal rainfall patterns that the later model predicts and the importance of seasonal issues in sewer system performance.

Climate Change and the Hydraulic Design of Sewerage Systems: Volume I - Climate Change Effects on Rainfall; IB Sensitivity Report: Validation of HadRM3 and Comparison with HadRM2

Ref: 03/CL/10/2            Price: £10

ISBN: 1-84057-327-9

This report is part of a major study on the impact of climate change on sewerage hydraulic design The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include, a summary of international drainage practice and predicted changes in sea levels and river flows. This report is one of 13 documents collated in 4 volumes.This document is one of three in volume I - Climate Change Effects on Rainfall. The other reports in volume I cover: - A report summarising the work carried out by the Met Office in producing predictions for extreme rainfall of the future based on the UKCIP98 Medium-High Scenario and the production of present day and future rainfall maps. Comparison of rainfall from FSR and FEH methods was also carried out. - A seasonality study on the differences between the rainfall output from UKCIP98 and UKCIP02 models. This report extended the work carried out on processing rainfall data covered by report IA in assessing the differences between the predictions from the HADRM2 model (the UKCIP98 output) and the HADRM3 model (the UKCIP02 output). The findings indicated that the changes in the future may be less extreme in terms of rainfall, but that both models should be considered as realistic scenarios for the future climate in the UK.

Climate Change and the Hydraulic Design of Sewerage Systems - Volume I: Climate Change Effects on Rainfall; IA - Climate Change and the Production of FSR, FEH and Year 2080 Rainfall Maps

Ref: 03/CL/10/1            Price: £10

ISBN: 1-84057-360-0

This report is part of a major study on the impact of climate change on sewerage hydraulic design.  The project was wide ranging, but with a principle focus on the performance of sewerage systems under future (year 2080) rainfall conditions and what changes might be needed in the hydraulic design of sewerage systems to address any problems that climate change might pose. Other issues include, a summary of international drainage practice and predicted changes in sea levels and river flows.

This report is one of 13 documents collated in 4 volumes. This document is one of three in volume I - Climate Change Effects on Rainfall. The other reports in volume I cover:

• A sensitivity analysis of the differences between the predictions of the UKCIP98 models and the UKCIP02 models
• A seasonality study on the differences between the rainfall output from UKCIP98 and UKCIP02 models.

This report covers the work carried out on processing rainfall data from the Hadley RCM models and producing climate change maps for the predicted change in extreme rainfall for various durations and return periods. The work was based on the Medium-High scenario UKCIP98 models available at the start of the study. Also available in association with this report are sets of maps to illustrate the differences between FSR and FEH rainfall and the uplift due to climate change. All maps are available as rastser (JPG) images included with the printed document.

Digital images (suitable for ArcView) are available separately.

Climate Change Implications for Water Treatment:Volume I - Overview Report

Ref: 11/CL/08/2            Price: £10

ISBN: 1 84057 610 3

This study assesses the impact of climate change on source water quality and its implications for the treatment of drinking water. It provides a framework for assessing potential risks to treatment processes and identification of adaptation responses.
The focus of the work has been to use existing data and the inland river and catchment water quality models, SIMCAT, ILC and INCA, to estimate potential changes in raw water quality due to climate change. A sensitivity-led approach has been developed assessing experiences during extreme weather and identifying design thresholds and climate related tipping points for treatment technologies. Assessments of potential changes in raw water quality and whether thresholds might be reached under a range of climate scenarios to the 2050s have been made.
Many impacts on source quality could be offset by integrated catchment management (controls on point and diffuse inputs). Otherwise, a range of water treatment risks and potential adaptation responses are presented and tested through case studies.
Generic risks to water treatment and uncertainties are considered. Site specific factors will be important in determining both raw water qualtiy and treatment risks and the report sets out a framework that companies can apply to:
- identify assets/processes at risk;
- define modelling/monitoring requirements; and,
- provide a risk-based assessment supporting investment.
The report is presented in two volumes. Volume 1 is an overview of the research and findings and Volume 2 consistes of two detailed technical reports. The first technical report sets out the modelling approach and projections of potential changes in raw water quality due to climate change. Current technologies are reviewed to determine those that would be most vulnerable to the specific changes identified. The second technical report analyses those vulnerable treatment processes to provide an understanding of potential implications using industry standard design models and case studies for specific sites.

Flow modelling of urban water distribution systems using water conservation fittings

Ref: 18/CL/12/3            Price: £10

ISBN: 1 84057 849 1

The aim of this work was to assess the impact of water conserving fixtures and fittings on UK building drainage (wastewater collection) systems of up to 100mm diameter, ranging from the point where the appliance discharges into the collection drain to the connection to the common sewer.

Climate Change Implications for Wastewater Treatment

Ref: 12/CL/12/1            Price: £10

ISBN: 1 84057 634 0

The project aims to identify: the likely impacts of cliimate change on the quantity and quality of wastewater within networks and hence the influent to treatment works; the extent to which climate changes will 'challenge' the operation of treatment works; and potential adaptation measures.
The approach taken differs from many as the starting point is the identification of 'system' design and/or performance thresholds; weather related changes driven by climate change factors are then used to assess the potential for exceedance of these thresholds. Where impacts have been identified, example adaptation measures and the capex/opex implications have been considered.
Having identified those processes/assets at risk, an adaptation framework has been developed that will provide companies with a mechanism to formulate their own adaptation strategies with a view to establishing, through monitoring, an evidence base for future investment.

Uncertainty & Risk in Supply/Demand Forecasting - Volume A

Ref: 03/CL/09/1            Price: £10

ISBN: 1-84057-284-1

Two Volume Report (Volume B supplied free of charge with Volume A) The report presents guidelines on how uncertainties in the individual elements of supply and demand can be brought together in an integrated way. The guidelines offer a hierarchical approach that allows the practitioner to select the most appropriate method for a given spatial area. At the simplest level the approach uses data from standard Water Resource Plan Tables, becoming progressively more complex requiring Monte Carlo simulation and then full simulation of the supply-demand balance at a weekly time step. The report also reviews the economic literature and provides guidance on how to interpret uncertainties and improve the process by which investment decisions are made.

Climate Change, the Aquatic Environment and the Water Framework Directive

Ref: 07/CL/06/5            Price: £10

ISBN: 1 84057 434 8

This project examined the likely effects of climate change on UK water industry compliance with the Water Framework Directive (WFD), set in the context of other expected changes, such as demographic shifts or changes in land-use.

A range of other drivers were identified - changes in energy prices, new regulatory targets for energy efficiency, water conservation and flooding, demographic and land use changes, and new environmental legislation that are likely to directly or indirectly affect the water industry.

The report proposes a Conceptual Assessment Framework to identify linkages between different drivers and industry operations and specific aspects of performance. The framework of drivers and effects was then used to assess the effects of the WFD, climate change and other drivers, which, with further development, could be used by water companies to identify appropriate responses.

Effects of Climate Change on River Water Quality

Ref: 05/CL/06/4            Price: £10

ISBN: 1 84057 402 X

The potential impact of predicted climate change on water quality in UK rivers, and its implications to the UK water industry, was investigated using a newly developed, fully distributed catchment-scale hydrological and water quality model, CAS-Hydro.  The model has been developed at the landscape scale, allowing an improved representation of how material is processed and transported across the landscape and into the river channel network.

Modelling of the River Derwent (Yorkshire) and a simulated catchment in southern England demonstrated a risk of climate-induced hydrological and water quality impacts on UK rivers, for the UKCIP 1998 medium-high emissions scenario in the 2080s.

Effects of Climate Change on River Water Quality Phase 3 - Scoping Study

Ref: 03/CL/06/3            Price: £10

ISBN: 1-84057-290-6

This is a scoping study for the third phase of investigations into the effects of climate change on river water quality. It firstly investigates what water quality parameters are of concern to the water industry, how they may be affected by climate change, and if this subsequent impact would then be significant. Consideration is then given to modelling approaches, including data issues, that would be needed to develop catchment based water quality models to represent the above, along with identification of catchments on which a completed modelling framework can be used.

Modelling the Effects of Climate Change on Water Quality in Rivers and Reservoirs

Ref: 01/CL/06/2            Price: £10

ISBN: 1 84057 247 7

Models of 5 rivers and 1 reservoir were used to determine whether they are capable of assessing changes in water quality under likely climate change scenarios. All of the models used suggest that no significant effects on water quality would result. However, it is not valid to conclude that significant effects will not occur. The reasons are found in the nature of the models used, in the way changes were assumed to happen and in the nature of the climate change scenarios themselves.

Review of River and Reservoir Water Quality Models for Predicting Effects of Climate Change

Ref: 00/CL/06/1            Price: £10

ISBN: 1 84057 188 8

A review was carried out of existing calibrated water quality models of rivers and reservoirs. A number of river models were identified as suitable candidates to predict the impact of climate change on water quality. these included Thames, Trend, Aire, Wharfe, Wye and Almond. Few reservoir quality models have been applied to UK reservoirs. The only models identified as suitable candidates to predict the impact of climate changes were two models of Wraysbury Reservoir: SULIS to predict water quality and PROTECH to predict any changes in dominant algae.