UK WATER INDUSTRY RESEARCH

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Topic catalogues

Topic catalogues list all of our reports published within each topic area / category with abstract and price. Please select a category to download the catalogue.

Water Mains & Services & Leakage

UKWIR maintains and is constantly adding to, an extensive library of reports which are deliverables from our research programme. Reports Catalogues are created to illustrate the reports that have been produced in each of UKWIR's research topic areas. These reports are freely available to UKWIR subscribers and they may be purchased from the UKWIR website by non-subscribers

 

Water Mains & Services & Leakage

Mains Cleaning Good Practice Report 

Ref: 18/WM/18/7            Price: £500
ISBN: 1 84057 858 0

The purpose of this UKWIR project was to gather information to identify and review the effectiveness of mains cleaning interventions and to develop evidence based best practice approaches to mains cleaning, inclusive of planning, design, costs, customer management, delivery and post-project assessment. The project produced:

(i) A Mains Cleaning Good Practice Guide document to provide guidance on the planning and implementation of mains cleaning strategies and interventions and a Decision Support Tool to assist users in selection of appropriate cleaning techniques and technologies for a particular application.

(ii) A Mains Cleaning Good Practice Report which presents the work that was carried out during this project and summarises the information gathered. The report provides conclusions and recommendations based on the finding of the project.

Non-destructive testing for plastic pipes 

Ref:             Price: £0
ISBN: 

Lifetime prediction of plastic pipelines is a critical aspect of any long term asset management programme. From the existing literature, material degradation, mechanical damage, fatigue, inherent flaws, operational pressure changes or welding defects are the most common reasons for failure in plastic water mains pressure pipes. Thanks to project sponsors, UK Water Industry Research (UKWIR) and the Engineering and Physical Science Research Council (EPSRC), this thesis will deliver some early stage research work needed to support any later development of a non-destructive or accelerated method to assist in predicting the lifetime expectancy and condition of PE pipes used in the water sector.

DOMS

DOMS - 15 Years on: Industry Workshop 1 Queen Anne's Gate London 8 July 2013

Ref: 13/WM/18/6            Price: £9
ISBN: 1 84057 694 4

The report contains the proceedings and output from a water industry workshop held in London on 8th July 2013.
The purpose of the workshop was to review companies' progress in implementing DOMS since the requirement was first introduced in 1998, to consider the implications of more recent developments such as Drinking Water Safety Plans, and to identify future challenges for the industry. Following an overview of the current state of regulation from the Drinking Water Inspectorate, six presentations on various aspects of DOMS implementation were given by water industry practitioners and these are included in the report.

Tools for the DOMS Forward-Looking Approach

Ref: 08/WM/18/5            Price: £28
ISBN: 1 84057 509 3

Previous studies to forecast discolouration potential of water networks have applied traditional statistical techniques such as regression analysis, and detailed process modelling. Such models have generally been hindered by insufficient data or quantification of the underlying processes and hence this project aimed to take a simpler approach that would work with current data and knowledge.
An index approach was developed, using data currently collected by water companies to generate three indices for water quality, vulnerability of the network, and hydraulic discolouration potential. A system discolouration index was calculated at water quality zone level, from the water quality and vulnerability discolouration indices, also including the hydraulic discolouration index when suitable data were available.
The index methodology was delivered in a spreadsheet tool, allowing users to set up the index calculation, import a range of data, and assess the discolouration potential of each zone or other area being studied. Individual zones may then be reviewed and interventions specified, with the tool compiling a list of zones, interventions, timings and costs.

Integrated Network Management Roadmap

Ref: 07/WM/18/4            Price: £14
ISBN: 1 84057 442 9

Water companies have long recognised that a more integrated approach to the management of distribution system functions could be beneficial but also that in practice it can be difficult to present the business case for integration initiatives.
This report provides a framework for water companies to consider Integrated Network Management (INM) approaches within water distribution network management. 
The framework provides the context in which INM should be considered through definitions, objectives and scope of INM with a common set of principles and components.  The remaining framework deliverables (a "Maturity Scale" and "Routefinder") allow companies to identify "Development Pathways" (DPs) towards INM best practice. Companies can develop their own DPs using the framework, and twelve key DPs are provided as appendices. The DPs indicate a vision for future INM practice and identify areas of further research.

DOMS - What Can We Learn? Research Report

Ref: 06/WM/18/3            Price: £27
ISBN: 1 84057 424 0

Existing water company Distribution Operation and Maintenance Strategies (DOMS) have been reviewed in order to identify current best practice and highlight areas where further development would be beneficial.

Research has been undertaken covering: 

  • the effect of mains bursts on iron concentrations and customer contacts regarding discolouration
  • the benefits of interventions such as systematic flushing and mains rehabilitation 
  • the design of cost-effective monitoring programmes
  • the quantification of costs associated with water quality service failures and capital and operational interventions.

A DOMS Guidance Manual (published separately) has been prepared providing comprehensive guidance on the development of a DOMS, addressing gaps or deficiencies in current practice. This Guidance Manual has been tested by water companies and modified as necessary to take account of practical findings and feedback.

DOMS Guidance Manual Volume 2: Guidance

Ref: 06/WM/18/2            Price: £27
ISBN: 1 84057 407 0

This Guidance Manual is intended to assist UK water companies in further developing their Distribution Operation and Maintenance Strategies (DOMS).

The purpose of a water company DOMS is to ensure customers are supplied with water of consistent or improving quality through appropriate operation and maintenance of the distribution system. This Guidance defines the scope and key concepts of DOMS and details an eleven-step development process, linked to the existing Common Framework Planning Process. Steps include addressing organisational issues, forward-looking analysis, site-specific studies, and feedback processes to ensure the DOMS is effective.

The Guidance Manual has been developed through consultation with water companies and Regulators, review of current DOMS and relevant literature, and analyses of company data including development and application of an approach for quantifying the benefits of interventions.

DOMS Guidance Manual Volume 1: Non-Technical Overview

Ref: 06/WM/18/1            Price: £10
ISBN: 1 84057 406 2

This document provides an overview in non-technical language of water company Distribution Operation and Maintenance Strategies (DOMS), expressed in a question and answer format. It is intended for water company managers and colleagues from outside the water quality arena.

The purpose of a water company DOMS is to ensure customers are supplied with water of consistent or improving quality, through appropriate operation and maintenance of the distribution system. The scope and key concepts of DOMS are summarised along with an eleven-step process for developing a DOMS. The latter is fully described in Volume 2 of the Guidance Manual.

The Guidance Manual has been developed through consultation with water companies and Regulators, review of literature, and analysis of water quality and associated data.

Flooding

A Risk Based Approach to Flooding

Ref: 11/WM/17/2            Price: £14
ISBN: 1 84057 591 3

This study has sought to develop a better means of setting priorities for investment to alleviate the risk of sewer flooding caused by hydraulic overloading. The methodology that has been developed aims to ensure that the risk of sewer flooding to customers is considered in a consistent manner, based on both the probability and consequence of flooding. It includes a 'two strand' approach, which considers acutal flooding incidents in conjunction with information on the potential risk of flooding in order to inform investment decision making. The report makes 15 recommendations for moving to a risk based approach and considers the implications for the regulatory framework. The main report is supported by 2 appendices: (i) a summary of the literature review carried out; and (ii) an assessment of data confidence.

UKWIR/FRMRC IUD Demonstration Projects

Ref: 10/WM/17/1            Price: £10
ISBN: 1 84057 552 2

New models developed by the Flood Risk Management Research Consortium were applied in selected drainage areas. The modelling contractors provided feedback that enabled the researchers to enhance their models. The experiences gained confirmed that 1D and 2D surface modelling techniques are complementary rather than competing. Although marginally more resource demanding at data preparation stage, the 1D approach is significantly less demanding than 2D modelling when it comes to file sizes and simulation time and enables rapid representation of options when developing responses to flooding problems. However, 2D surface modelling provides more effective graphical representation of flood pathways and receptors when carrying out a flood risk assessment. A conceptual model for integrated urban drainage modelling is presented.

Leakage

The Impact of Burst-Driven Mains Renewals on Network Leakage Performance

Ref: 18/WM/08/67            Price: £150
ISBN: 1 84057 863 7

A burst-driven renewal programme can achieve a reduction in burst frequencies leading to a reduction in the natural rate of rise (NRR) of leakage. This results in a reduction in the optimal survey frequencies, in turn reducing the costs of active leakage control (ALC) to maintain leakage at the current level. Understanding the full impacts on a range of key performance indicators (KPIs) for a DMA improves will help the industry to take a full totex view of benefits of future investment and allow existing asset management models to be calibrated appropriately.

This study assessed the historic impact of burst-driven mains renewal (mains only) on the operational costs of leakage management on DMA network performance. A representative industry dataset of 487 burst-driven mains renewal schemes from four Water Service Providers (WSPs) was included. Data was normalised to mitigate variation linked to operational, geographic, and climate differences between WSPs. The normalised dataset was used to build non-linear models to predict the performance of KPIs at the level of DMA based on DMA characteristics and current performance.

KPI performance was successfully modelled for each of NRR, total DMA mains repair numbers, mains repairs numbers of renewed sections, leakage, minimum achieved leakage, and supply interruptions.

This report details the new model development and approaches to quantify and optimise the targeting of burst-driven mains renewal programmes by application of individual company data sets. The findings have been incorporated into an Excel tool for ease of application to individual company data sets to support investment planning and optimisation.

Fast logging for improved estimation of household night use

Ref: 17/WM/08/66            Price: £200
ISBN: 1 84057 848 3

An important part of quantifying leakage using DMAs is removing the legitimate night use from the minimum night flow. Over recent years several water companies have been investigating the use of 'fast logging' techniques and their application to estimating night use.

The onjectives of this project were to review the various fast logging systems for estimating night use, demonstrate the effectiveness or performance of the techniques and to provide guidance on how to use and supply the methods.

The report provides guidance on how to use fast logging in small areas and in DMAs. Various factors impact how much of the toal night use can be detected with fast logging, and these are explained in the report. Guidance is also given on how to apply fast logging for consistent regulatory leakage reporting.

Achieving Zero Leakage by 2050: Water Accounting and Quantification Methods

Ref: 17/WM/08/65            Price: £18
ISBN: 1 84057 840 8

This project is one of five UKWIR projects that form a strategic research programme to address the question “How can we achieve zero leakage by 2050?”. It covers the subject of water accounting and quantification methods.

The project has considered the current sector knowledge in the UK and overseas relating to the quantification of leakage. A detailed technical review of the area, including each aspect of the ‘top down’ and ‘bottom up’ assessment of leakage estimates and all factors which comprise the reported leakage key performance indicator, has been undertaken.  

You can download this report FOC via the UKWIR website. 

Achieving Zero Leakage by 2050: Laying Leak Free New Networks

Ref: 17/WM/08/64            Price: £14
ISBN: 1 84057 839 4

This project is one of five UKWIR projects that form a strategic research programme to address the question “How can we achieve zero leakage by 2050?” The project aimed to identify what research and development will be required to facilitate the path to zero leakage.

The objective of this report is to identify the issues (design, materials and workmanship) that currently contribute to high leakage rates and to examine how changes to current installation practices or the need for new techniques are required to facilitate laying leak-free new networks.

You can download this report FOC via the UKWIR website. 

Achieving Zero Leakage by 2050: Leak Repair Techniques

Ref: 17/WM/08/63            Price: £13
ISBN: 1 84057 838 6

This project is one of five UKWIR projects that form a strategic research programme to address the question “How can we achieve zero leakage by 2050?” The project aimed to identify what research and development will be required to facilitate the path to zero leakage.

This report focuses on leak repair techniques and in particular no-dig solutions to water leakage.

You can download this report FOC via the UKWIR website. 

Achieving Zero Leakage by 2050: Leakage Detection and Location – Non-acoustic Methods

Ref: 17/WM/08/62            Price: £12
ISBN: 1 84057 837 8

This project is one of five UKWIR projects that form a strategic research programme to address the question “How can we achieve zero leakage by 2050?”. The project aimed to identify what research and development will be required to facilitate the path to zero leakage.

This report focuses on non-acoustic methods of leak detection and location. It is complemented by a review of acoustic methods that has been carried out by the Institute of Sound and Vibration Research at the University of Southampton (reported separately).

You can download this report FOC via the UKWIR website. 

Achieving Zero Leakage by 2050: Leak Detection and Location Methods - Acoustic Leak Detection

Ref: 17/WM/08/61            Price: £10
ISBN: 1 84057 836 X

The work described in this report was undertaken under the UKWIR zero leakage 2050 programme. This report addresses Lot 2, Leak Detection and Location Methods, and focuses on addressing issues related to this area of work. In particular, research related to detection and location methods which exploit acoustics and/or vibration in some form is addressed. This includes, for example, correlation methods, acoustic emission methods and optical fibre sensing methods; thus the work extends beyond those methods which are traditionally thought to be “acoustic”. The work focuses on both potential enhancements to existing technologies and possibilities for novel techniques.

You can download this report FOC via the UKWIR website. 

Achieving Zero Leakage by 2050: Basic Mechanisms of Bursts and Leakage

Ref: 17/WM/08/60            Price: £17
ISBN: 1 84057 835 1

This project is one of five UKWIR projects that form a strategic research programme to address the question “How can we achieve zero leakage by 2050?”. This project covers the subject of the basic mechanisms that control bursts and leakage; these typically stem from the materials that are used in the various UK water networks and the manner in which they degrade over time.

You can download this report free of charge

Factors Affecting Minimum Achieved Leakage

Ref: 16/WM/08/58            Price: £200
ISBN: 1 84057 818 1

The Minimum Achieved Leakage (MAL) is the lowest level of leakage achieved over a specified period of time, under respective Active Leakage Control (ALC) policies. This report examines the relationship between MAL, calculated using a consistent methodology, and a range of physical and operational explanatory factors for 8 Water Service Providers (WSPs). 
  
Predictive functions have been developed which estimate MAL at District Metered Area (DMA) level in response to explanatory factors. Nationally representative functions can be applied for a range of MAL frontiers for comparative purposes. Functions can be calibrated to WSPs for ‘gap filling’ where calculation of DMA MAL has not been possible, and to estimate future changes in MAL due to ageing, pressure management, asset renewal, DMA size, and reported and detected leak repair frequencies for customer and company-side assets. Functions can also be used to integrate ALC, pressure management and infrastructure renewal interactions within leakage economic modelling.

Measuring the performance of leak detection technicians

Ref: 15/WM/08/57            Price: £350
ISBN: 1 84057 794 0

The project reviewed current practice and methods together with company views on their practicality and unintended consequences.

The project has resulted in the development of an expectation model for the find rate of leakage detection technicians. This provides the basis to take into account two primary explanatory factors in interpreting the data between different groups of technicians and between utilities and hence provides a basis to benchmark their performance.

The project has been unique in that it has included a pilot where a given DMA has been surveyed by different technicians immediately following each other. This has provided a significant insight into the leakage detection process, its difficulties and issues.

The pilot has given an initial indication of possible incentivisation techniques, their issues and benefits. This could provide the basis for more extensive trials within utilities.

The Economics of Supply Pipe Leakage

Ref: 15/WM/08/56            Price: £300
ISBN: 184057 763 0

This project has provided a methodology for assessing the most economic process for management of customer-side leakage, allowing the options for customer side leakage management to be considered alongside all other leakage management options in SELL models.

The economic policy is the least cost mix of repair / replace and the level of company contribution that results in the lowest overall sum of:

- Cost of lost water
- Cost of dealing with customers
- Cost of supply pipe repairs and / or replacements.

There are also a range of issues that can impact on both the level of supply pipe losses and the cost of the SPL policy. The frameworks allow companies to explore the impact of:

- Customer metering
- Separation of shared supplies
- Transfer of ownership.

The supplied MS Excel frameworks(s) and SELL integration module can be used to identify the economic level of supply pipe losses based on company specific information.

Software on CD: MS Excel 2010 & MS Excel Macro-Enabled Worksheet

Leakage Upstream of District Meters

Ref: 15/WM/08/55            Price: £200
ISBN: 1 84057 751 7

While there has been significant research on leakage within district meter areas, leakage on the part of the network between the distribution input and district meter is less well understood. Water losses from trunk mains and service reservoirs arise from a variety of sources that require different approaches to management. This has led to informal management of upstream leakage and limited development of overall strategy. The extent of data collection to support analysis varies significantly across the industry.

This project has provided a framework for the economic assessment of upstream leakage and identified the advantages and disadvantages of different Active Leakage Control options to managing upstream leakage. Comparison of capital-intensive approaches to management with increased operational expenditure is included, as is incorporation within Sustainable Economic Level of Leakage analysis. Case study applications of the framework have been developed to assist companies in understanding the economic calculations and tailor these to their own circumstances.

The Accuracy of District Meters

Ref: 15/WM/08/54            Price: £300
ISBN: 1 84057 750 9

District meters are essential to leakage management and increasingly used in pressure management and smart networks. Understanding their performance, therefore, is important. Currently the majority of district meters are turbine types but the proportion of electromagnetic meters is increasing. Data from many sources have been analysed to identify the influence of factors, including sizing, installation and age, on installed accuracy. Electronic verification maintains confidence in electromagnetic meters and hydrant meters used to check mechanical meters when problems are suspected. The uncertainties of individual meters should be evaluated when compiling bottom up leakage estimates. However, this process requires good asset records.

Improved Household Night Use Allowances

Ref: 14/WM/08/53            Price: £200
ISBN: 1 84057 738 X

The project investigated household night use and the factors that influence the night use. The study found that night use varies through the year, and between different geographic regions. However, most companies still apply a single value throughout the year and to all DMAs.

The day-to-day variability (as a proportion of the mean) in night use is much higher than that for daily consumption, whilst the seasonal variation is much lower. The study found that whilst it is extremely difficult to predict the variation in night use, it is possible to monitor the trend in night use through the year using a control group monitor.

Spatially, the study found that household night use can be estimated at DMA level, based on DMA and socio-demographic attributes. A set of normalised factors were developed that can be used to adjust night use across different DMAs in a company.

Quantification of Customer Supply Pipe Leakage - A Guide for Data Collection

Ref: 13/WM/08/52            Price: £12
ISBN: 1 84057 705 3

Understanding of the UK supply pipe asset base is limited. Although not owned by the water companies, the supply pipe is a source of leakage.

The report identifies the diverse industry drivers for greater understanding of supply pipe leakage (SPL). Factors such as increasing meter penetration affect SPL estimates significantly.

The current methodology for estimating supply pipe leakage lacks sufficient data in some areas to produce reliable results.

The report provides a specification for additional data collection that will allow improved estimates to be prepared. The data collection approach is independent of the SPL estimation methodology to be applied, allowing further development of the methodology to overcome current issues.

A national initiative is proposed that will enable water companies to collect data in a consistent manner. Following future collection of data, and collation of suitable existing data, improved analysis can be obtained from the pooled data resource.

Alternative Methods for the Quantification of Leakage

Ref: 13/WM/08/51            Price: £28
ISBN: 1 84057 697 9

Currently most UK water companies use the minimum night flow method for quantifying and reporting leakage levels. As companies' domestic and commercial meter penetration increases it should be possible to carry out DMA level water balances which will offer an alternative methodology for quantifying leakage. This project researched whether it was possible to build a generic model that would predict a meter penetration level at which the DMA level water balance could be considered more accurate. The project concluded that building such a generic model was not possible. It did, however, produce a model that can be used as a model for a single DMA. This model will determine which water balance, the traditional MNF or the alternative DMA level, would provide a more accurate determination of leakage at the DMA's current level of domestic meter penetration.

The model also indicates, at a company, WRZ or other level, the meter penetration point at which the alternative method would provide a higher proportion of more accurate estimates.

Effect of Weather on Leakage and Bursts

Ref: 13/WM/08/50            Price: £27
ISBN: 1 84057 683 9

Weather conditions have had a severe impact on bursts and leakage in recent years and water companies are seeking relationships to explain and predict this impact for severe weather events. This report explores available weather parameters and proposes models to identify the probability or severity of bursts or leakage exceedance above a threshold. Weather parameters derived fro measurements such as air temperature and soil moisture deficit are used. The influence of source watter temperature is identified; temperate borehole source water shows less reaction to weather extremes than open water or river sources. This effect, other local factors (eg soil type) and data limitations prevent the development of a more universal model. However, the report provides sample models that can be adjusted to accommodate these differences in the absence of specific modelling of the local company area.

Assessment of Low Flow Components of Night Use and the Water Balance

Ref: 12/WM/08/48            Price: £19
ISBN: 1 84057 646 4

The project investigated the effect of un-measured and under-registered low flows on night-use allowances in leakage calculations, and on estimates of household per-capita consumption.
The study found that the most significant contribution to un-measured and under-registered flows arises from the existence of continuous low flows. Night-use and per-capita consumption monitors need to be adjusted to compensate for the un-measured and under-registered part of this continuous low flow.
Best estimates of the volume flow rate of 'continuous' low flow have been derived during the study and these can be used to compensate for meter non-registration and meter under-registration. Guidance on how to apply these estimates to household night-use and PCC monitors is provided in the report.
The improved understanding of the effect of un-measured and under-registered low flows on night use, and hence leakage calculations, will help the industry to quantify, target and report leakage more effectively.

Leak Detection on Plastic Pipes

Ref: 12/WM/08/47            Price: £25
ISBN: 1 84057 647 2

Conventional leak detection techniques often prove ineffective in locating leaks accurately due to the poor acoustic properties in polyethylene pipe and issues such as highly attenuated leak signals, wave speed estimates, poor signal to noise ratios and the sensitivity of sensors.
The project included numerous controlled field tests to investigate and assess the effectiveness of current leak detection on plastic pipe by reviewing the most appropriate techniques, optimum leak noise correlation methodology and the effective range of existing techniques and also identifying opportunities to support innovation.

Best Practice for the Derivation of Cost Curves in Economic Level of Leakage Analysis

Ref: 11/WM/08/46            Price: £23
ISBN: 1 84057 613 8

Cost curves are required in economic level of leakage analysis to relate the total or marginal cost of leakage control to the level of leakage. This report reviews current methods for deriving cost curves and identifies changes that can be made to improve their robustness and accuracy. Issues such as the level of uncertainty, leakage control efficiency and impact of seasonal variations are also considered. The report identifies best practice for elements of current methods where this can be established and challenges current assumptions otherwise. The interactions with, and dependence on, other elements of the ELL calculation are noted: these include policy minimum, natural rate of rise and the cost of repairs. The report also provides direction for further method development aimed at improving cost curve derivation in a manner consistent with operational practice and investment strategy.

Managing Leakage 2011

Ref: 10/WM/08/42            Price: £550
ISBN: 1 84057 563 8

There are two versions of this report available. This version of the report includes seven reports on Managing Leakage, an executive summary, glossary and list of references.

The full priced version "Managing Leakage 2011 – References Included" also includes 20 original UKWIR reports on CD at a significantly discounted price compared to when buying the reports individually.

The original 'Managing Leakage' was published in 1994 by WRc in co-operation with the Water Services Association and the Water Companies Association. It fast became the definitive reference document for leakage control, not just in the UK but throughout the world, with the methodologies recommended in the document identified as best practice.

Since then, research and practice in leakage management has continued to develop with over thirty reports published by UKWIR alone on the subject and related topics. Although much of the original document is still relevant, more recent research has added to the knowledge in some areas, such as leakage economics, pressure management, asset management and leakage location technology.

Managing Leakage 2011 includes those parts of the original document which are still relevant but also more recent studies and developments with over 100 documents referred to and listed. In order to facilitate the use of the document, it has been produced in an electronic format.

Managing Leakage 2011 - References Included

Ref: 10/WM/08/42            Price: £3000
ISBN: 1 84057 563 8

There are two versions of this report available. This version of the report includes seven reports on Managing Leakage, an executive summary, glossary and list of references. It also includes electronic versions of over 20 previous UKWIR reports, which are referenced in the document and its Bibliography. Not only does this incur a saving of £1,630 compared to purchasing the reports individually, it also allows for much easier cross referencing of the documents.

The original 'Managing Leakage' was published in 1994 by WRc in co-operation with the Water Services Association and the Water Companies Association. It fast became the definitive reference document for leakage control, not just in the UK but throughout the world, with the methodologies recommended in the document identified as best practice.
Since then, research and practice in leakage management has continued to develop with over thirty reports published by UKWIR alone on the subject and related topics. Although much of the original document is still relevant, more recent research has added to the knowledge in some areas, such as leakage economics, pressure management, asset management and leakage location technology.

Managing Leakage 2011 includes those parts of the original document which are still relevant but also more recent studies and developments with over 100 documents referred to and listed. In order to facilitate the use of the document, it has been produced in an electronic format.

A Survey of Practices for the Detection and Location of Leaks

Ref: 11/WM/08/45            Price: £14
ISBN: 1 84057 592 1

The objective of this report is to provide guidance in the application of leak localising and detection techniques to individuals responsible for managing the leak detection process.
Implementing the recommendations should lead to more effective and consistent decision making in both the selection of detection methods and the organisation of leak detection operations.
The report includes a decision-making matrix (as a separate spreadsheet) as a guide to the selection of the most appropriate techniques for pinpointing leaks. The report also includes a set of recommendations about data requirements, target setting and training.
The recommendations are based on information obtained from interviews with leakage managers and leakage technicians in nine companies, and equipment suppliers, along with a review of case studies.

Long Term Leakage Goals

Ref: 11/WM/08/44            Price: £25
ISBN: 1 84057 583 2

Leakage targets in the UK water industry are meant to achieve the leakage level that produces the lowest overall cost for society. However there is inherent uncertainty about what these should be in the medium term (5 years) and even more so in the long term (25 years). This project aimed to assess what leakage level could be achieved in the long term, the actions required, technical constraints, critical factors, uncertainties and costs.
The work was carried out using two models of leakage processes, both calibrated to conditions in a typical UK water undertaking and based on real costs of leakage reduction. Projections were made for a range of strategies (including pressure management, active leakage control and renewal); asset deterioration rates and future operating conditions.
This report will be useful for water resource planning, leakage reduction strategies, leakage economics and to understand the impact of leakage reduction on customer's bills in the long term.

Leakage from PE Pipe Systems

Ref: 10/WM/08/43            Price: £34
ISBN: 1 84057 579 4

Polyethylene is now the preferred material for both new and rehabilitated distribution mains. There has been growing concern, however, surrounding PE pipe joint integrity. This UKWIR project was therefore initiated to quantify the scale of potential leakage problems on existing PE systems and drive improved design and construction methods for installing PE pipe.
As electrofusion joints have been found to be significantly more likely to fail than butt fusion and mechanical joints, this is where the focus of the project has been directed. Analysis of failure data and destructive electrofusion joint test records suggest that 20 percent of electrofusion joints will have a life span considerably less than the 50 year design life.
Recommendations from the project include: making changes to current standards for PE pipe installation; improved data capture, training and licensing of welders, and testing during installation; and the need to overcome issues associated with coiled pipes.

Factors Affecting the Natural Rate of Rise of Leakage

Ref: 09/WM/08/40            Price: £24
ISBN: 1 84057 530 1

 The natural rate of rise (NRR) in leakage relates to the underlying rate at which leakage increases within a system. This report examines the relationship between NRR, calculated using the UKWIR best practice methodology, and a range of network characteristics for 6 Water Service Providers (WSPs). Predictive funtions have been developed which estimate NRR at DMA level in response to variations in key chacteristics. Generic funtions can be applied or calibrated to WSPs to estimate future changes in NRR due to ageing, pressure management, mains renewal, DMA size, and network disruption. Functions can be used for 'gap filling' where calculation of DMA NRR has not been possible, and to integrate ALC, pressure management, and infrastructure renewal within leakage economic modelling. in addition a field study undertaken within 3 WSPs measures flow rates for a range of leak types over a 24 week period to assess the degree to which leaks grow.

Large Diameter Trunk Main Failures

Ref: 09/WM/08/39            Price: £31
ISBN: 1 84057 524 7

The failure of large diameter trunk mains, though rare, can be highly disruptive to both Water Company and the general public. Failures can have major consequences in terms of public safety, damage to property and interruptions to supply.
This project brings together knowledge and experience from across the UK to gain insights into the possible causes of failure in trunk mains. It has investigated historic trunk mains failure data from UK water companies and identified deficiencies in data quantity and quality. The project has focussed on pooling data from 13 water companies to support a statistical methodology for predicting trunk main failures. A modelling tool has been developed to support effective capital maintenance planning in the long term.
In addition, an accompanying data protocol has been produced, which, if adopted by the industry, will lead to better understanding and more robust modelling of trunk mains failures in the future.

Leakage in Trunk Mains and Service Reservoirs

Ref: 08/WM/08/38            Price: £23
ISBN: 1 84057 512 3

Distribution leakage has long been a focus for the UK water industry but as this element has been successfully reduced over recent years, other elements such as leakage from trunk mains and service reservoirs are assumed to be increasing their relative proportion of water loss. Consequently they are becoming an increasingly important and visible component of the water balance.
This report identifies the range of techniques in use across the UK water industry to quantify, locate and pinpoint leakage from trunk mains and service reservoirs. The report provides guidance on the effectiveness and appropriateness of different practices with respect to estimating and controlling leakage from trunk mains and service reservoirs and aims to provide companies with more information to help them deploy limited resources with more precision and effectiveness.

Separation of Customers Night Use from Leakage in Night Flow Analysis

Ref: 08/WM/08/37            Price: £19
ISBN: 1 84057 472 0

There is an increasing expectation that the district metered area (DMA) will provide a reliable measure of leakage for operational purposes. However, issues with DMAs are becoming increasingly apparent as DMA sizes decrease, leakage reduces and analysis is attempted over shorter time intervals.
To meet these expectations greater understanding is required of the nature of the flow components in a DMA to improve the separation of leakage and night use. The project develops further this understanding and provides an alternative methodology which accounts for the characteristics of predominantly household DMAs while also exploiting the potential in using recording intervals shorter than the 15-minutes conventionally used.
The methodology provides a sound basis for further development to account for more complex DMA configuration and composition (including non-households) beyond those DMAs already accommodated. Implementation in practice requires only minor changes to data loggers and receiving systems.

Managing Seasonal Variations in Leakage

Ref: 07/WM/08/35            Price: £27
ISBN: 1 84057 460 7

This project has improved the understanding of the range of seasonal variations in leakage around the UK and identified some of the underlying factors and the mechanisms. The study concluded that seasonal variations in leakage are common during the winter and characterised by an increase in leakage and bursts. Analysis and modelling suggests seasonal variations in leakage appear to be a function of the pipe temperature compared to its temperature during installation, variable ground support and movement and the degree of ground saturation. A number of recommendations have been made in the report to enable companies to manage seasonal variations in leakage.

A Comparison of Leakage Practice and Leakage Levels in the UK and Netherlands...

Ref: 06/WM/08/34            Price: £17
ISBN: 1 84057 405 4

This is a collaboration between the water industries of the UK and the Netherlands. It explored the differences in leakage levels and leakage control policies between the two countries and identified a number of physical factors which account for the differences in leakage. Three UK leakage detection teams went to Holland to evaluate UK leak detection techniques in the Dutch networks. The study showed that the 'top-down' leakage analysis method at DMA level is feasible, but only where a majority of the properties are metered. In these DMAs the method could be applied to routinely validate the 'bottom-up method'.

Towards Best Practice for the Assessment of Supply Pipe Leakage

Ref: 05/WM/08/32            Price: £14
ISBN: 1 84057 397 X

A supply pipe leakage estimate is required for regulatory reporting. However, a more detailed understanding of proportion of total leakage that is associated with supply pipes will also improve operational allocation of leakage reduction resources.

A methodology is proposed that is based on the bursts and background estimate (BABE) method modified for service pipes and will allow consistent inter- and intra-company comparisons. The methodology can be applied with only basic levels of available data, but results will become more representative as company-specific data are collected and applied to the analysis.

The proposed approach cannot yet be regarded as definitive best practice as there is only limited data and experience of its application. However the framework provided is sufficient to allow best practice to develop. Approaches to further data collection are detailed and further research is recommended.

Natural Rate of Rise in Leakage

Ref: 05/WM/08/33            Price: £12
ISBN: 1 84057 393 7

The natural rate of rise in leakage relates to the underlying rate at which leakage increases within a system. NRR is essential for determining the intensity of active leakage control that is required to maintain leakage at a specific level, and the range of methodologies for assessing leakage/cost relationships outlined in the Tripartite Report all rely on a robust assessment of NRR. As an indicator of asset condition, NRR is also central to mains replacement strategy.
This report examines and compares the theoretical and empirical attributes of the alternative NRR assessment methods, the 'burst frequency' and 'nightline' approaches, and provides a set of procedures which facilitate the derivation of consistent NRR assessments suitable for (i) area-level leakage management budgeting; (ii) targeting mains renewal; (iii) targeting active leakage control resources at DMA-level; and (iv) deriving leakage control cost curves for determining economic levels of leakage.

Cost Effective Leakage Survey Practice

Ref: 04/WM/08/31            Price: £21
ISBN: 1-84057-325-2

A framework has been developed for processing and analysing cost and effectiveness data for DMA prioritisation and leak detection techniques. Initial guidance on suitable assessment criteria is also presented in the report. The necessity for further data collection and field testing to develop comprehensive guidelines was highlighted in the project.

Background Leakage

Ref: 03/WM/08/30            Price: £13
ISBN: 1-84057 283 3

Background leakage is an important concept in leakage economics. This report assesses the methodologies available for investigating background leakage and recommends a best practice. The report also develops the understanding of the factors affecting background leakage and goes some way in explaining the differences between operating areas. The relationship between background leakage and the leakage policy adopted is investigated and a new term 'policy minimum' is suggested which is an assessment of the lowest level of leakage that can be attained for a given policy. Possible drivers which might determine a policy minimum are discussed.

Service Pipe Leakage

Ref: 02/WM/08/28            Price: £31
ISBN: 1-84057-278-7

Leaks from services pipes account for a significant proportion of unaccounted for water in UK water distribution networks. This report covers various aspects of the subject looking principally at detection and location methods. A comprehensive decision chart has been developed to aid the user in selecting the most likely lowest cost repair solution. A prototype twin wall insertion probe has been developed which enables the precise location of a service pipe leak to be determined. The bulk of the report is dedicated to the experiments conducted using neural networks to attempt to characterise service pipe leaks. The aim was to use the acoustic signals given off by a leaking pipe to determine the location and size of the leak as well as the material from which the pipe was made. Whilst some results are promising there is a considerable way to go before the recognition software would be of any commercial value.

Leakage Index Curve and the Longer-Term Effects of Pressure Management

Ref: 03/WM/08/29            Price: £14
ISBN: 1-84057-280-9

This project considers the various methods available of predicting both the short and long term effects of pressure management. The report concludes that there is little practical difference between the methods for the majority of conditions but some have advantages at the extremes and that there is a large variability in pressure-leakage relationships for individual zones. The main recommendation is that a linear pressure-flow relationship can be used in large zones, or where high precision of results is not a priority. There is no evidence of a relationship between pressure and mains repair frequency. Keywords: leakage management, pressure management

Household Night Consumption

Ref: 02/WM/08/27            Price: £21
ISBN: 1-84057-271-X

The implementation of the approach detailed in this report will provide companies with a robust statistical method for the estimation of household night consumption, which takes account of known property attributes for each area of application. An improved approach to night flow analysis has been provided which is consistent with the proposed night consumption modelling approach. Taken together, these two components will provide a statistically sound and unbiased approach to leakage estimation, allowing companies to place greater confidence in reported leakage figures. The use of area-specific household night consumption allowances will improve the targeting of leakage control resources.

A Review of Leakage - Updating Managing Leakage Methodology and Theory

Ref: 97/WM/08/10            Price: £11
ISBN: 1 84057 036 9

The first update of 'Managing Leakage', the 1995 water industry report. Economics of leakage methodology, both short and long term is developed in detail. There are case studies on whole- life costing. Seven key areas of UKWIR research are summarised including marginal costs, water balances, social and environmental costs, economics of supply pipe leakage and effects of mains rehabilitation.

Estimating Legitimate Non- Household Night Use Allowances

Ref: 99/WM/08/26            Price: £18
ISBN: 1 84057 165 9

This study has produced a robust and generalised methodology that can be used by individual companies to more accurately determine legitimate non-household metered use. This should improve the accuracy of regulatory reporting and of leakage monitoring and management. Tests indicated that division of the population into a set of groups on the basis of user- type can produce significant accuracy improvements in assessed allowances. The methodology therefore incorporates a user- type stratification design. Alternative design possibilities are also presented and examined in the report. The estimation approach relates individual meter night- use to average billed volume (ABV), for each user- type.

Best Practice for Unmeasured Per Capita Consumption Monitors

Ref: 99/WM/08/25            Price: £21
ISBN: 1 84057 162 4

Within the annual water balance, water companies have to estimate unmeasured per capita consumption (PCC) for which various methods are available. The primary project objective was to develop best practice for estimating unmeasured PCC. Other objectives were to identify explanatory factors for regional variation in PCC, to assess the benefits of adopting a per household measure and to undertake a feasibility study for a national micro- component monitor. The report contains detailed descriptions of best practice for estimating unmeasured PCC and guides the reader through the steps for designing or reviewing PCC monitors. Conclusions for the other objectives are also given.

The Environmental and Social Value of Leakage Reduction

Ref: 99/WM/08/24            Price: £15
ISBN: 1 84057 161 6

This research develops a methodology for incorporating environmental and social costs and benefits into the evaluation of water management options. Approaches to valuing changes in external costs are developed. In addition, the methodology provide an approach to updating historical estimates of cost, taking account of existing interventions aimed at internalising external costs, and allowing for sunk capital. The methodology is illustrated with representative case studies.

A Manual of DMA Practice

Ref: 99/WM/08/23            Price: £15
ISBN: 1 84057 160 8

The manual provides guidance to staff engaged in managing district meter areas (DMAs). It guides the practitioner through the stages of :
1.  setting up and maintaining districts,
2 monitoring leakage,
3 selecting leak detection equipment,
4 directing leak detection staff,
5 pressure management,
6 dealing with problem DMAs,
7 using DMA data for other purposes.
The manual is intended as a guide for staff of varying experience in managing DMAs. It provides references to various techniques, but recognises the very variable circumstances across the water industry.

The Natural Rate of Rise in Leakage

Ref: 99/WM/08/22            Price: £16
ISBN: 1 84057 159 4

This research examines the theoretical and empirical determinants of the natural rate of rise in leakage (NRR) over time, in order to advance the development of an 'NRR Equation' which can be used to produce reliable estimates of the NRR over a wide variety of different DMA conditions. Once derived from a sound empirical basis, such a specification might not only be utilised to determine optimal DMA intervention and exit times and the unit costs of leakage control, but might also be appropriately calibrated in order to produce a measure for asset condition and deterioration.

Leakage Estimation from Night Flow Analysis

Ref: 99/WM/08/21            Price: £12
ISBN: 1 84057 158 6

Existing methods for providing leakage estimates for reporting purposes, using data from continuously monitored areas are reviewed. Analysis concentrated on night use allowances and 15 minutes flow sampling intervals using standard meters and loggers It is recommended that reported leakage is based on a rolling 7 day 20 percentile using the minimum rolling hour each night. The method will give a leakage estimate for each day. Monthly and annual estimates should be based on the average of available data for the relevant period.

Maintenance

Benefits and Disadvantages of Using 'No-Disruption' Repair Techniques

Ref: 14/WM/12/33            Price: £200
ISBN: 1 84057 734 7

Water companies are coming under increasing pressure to ensure that interruptions to water supplies are prevented or minimised as far as possible. This has resulted in increasing use of 'no disruption' repair techniques for leaks and bursts. This research project undertook a technical appraisal of water company experience of pipeline repair using a range of techniques, covering traditional ('disruptive') and 'no disruption' repair, with the aim of assessing the impact of the method selected on short and long-term network performance and on the consequent service to customers.

The Contractor, CH2M HILL, has analysed the data from a number of water companies within the United Kingdom to assess the impact of different network repair technologies on subsequent performance of the water distribution network. A Decision Support Tool was developed to enable water companies to select the best technique to use in various circumstances.

Locating Underground Plant and Equipment - Costed Proposals for a Research Programme

Ref: 03/WM/12/5            Price: £12
ISBN: 1-84057

There is no abstract for this report.

Deterioration Rates of Long-life, Low Probability of Failure Assets: Project Report

Ref: 11/WM/13/2            Price: £23
ISBN: 1 84057 609 X

Several asset groups within the water industry can best be described as long life, low probability, extreme consequence of failure assets. Inclusion of these assets within company investment plans requires consideration of the probability and consequences of asset failure in the future. Where failure probabilities are low, few historical failure data will be available for analysis. Therefore, failure probability must be estimated using alternative methodologies. Nonetheless, if a robust justification for capital maintenance is to be made, these methodologies must be objective, evidence based and capable of external audit. With this objective in mind, the study has undertaken the development of deterioration models based upon sound science and technology. A toolbox has been developed covering key asset groups and failure modes which also includes worked examples and case studies which demonstrate a range of real life scenarios.
The study considered the model outputs in the context of a wider risk-based process, which couples the consideration of failure consequence with the deterioration models in order to support sound intervention planning.

Deterioration Rates of Long-life, Low Probability of Failure Assets: Literature Review

Ref: 11/WM/13/1            Price: £14
ISBN: 1 84057 608 1

Several asset groups within the water industry can best be described as long life, low probability, extreme consequence of failure assets. Inclusion of these assets within company investment plans requires consideration of the probability and consequences of asset failure in the future. Where failure probabilities are low, few historical failure data will be available for analysis. Therefore, failure probability must be estimated using alternative methodologies. Nonetheless, if a robust justification for capital maintenance is to be made, these methodologies must be objective, evidence based and capable of external audit.
Before deterioration models and an overall approach were developed for the different asset types, an extensive literature review was carried out to identify how the problem is approached worldwide, both in the water industry and elsewhere.

Minimising Street Works Disruption: An Overview of the VISTA Project

Ref: 10/WM/12/28            Price: £16
ISBN: 1 84057 567 0

VISTA is a four year joint project with a consortium of partners. UKWIR is the lead co-ordinating partner with Leeds and Nottingham Universities providing the reserach input. In addition there are over 20 utility and other sector partners. The object of the project was to 'research techniques to enhance and integrate existing legacy asset information, together with dynamically acquired accurately geo-referenced data in the street and develop novel techniques to display the resulting knowledge to digging teams and network planners appropriately'. This report describes work carried out by the two main research oorganisations; the School of Computing at the University of Leeds and the Institute of Engineering Surveying and Space Geodesy (IESSG) at the University of Nottingham as well as the field trials of the outputs, and provides an overview of the project.

Smart Sensors for Buried Utility Location and Performance Monitoring

Ref: 09/WM/12/26            Price: £20
ISBN: 1 84057 546 8

The Smart Pipes project was initiated in order to start developing pipes which could provide information about their performance, so called 'smart pipes'. Research was conducted at the University of Birmingham between 2006 and 2009 and aimed to prove the concept of a remotely-interrogated 'smart' water pipe. Large numbers of small sensors (or sensor circuits) are incorporated into (or near to) the pipe and associated communication systems are deployed in order to montor the condition or status of the pipe and /or its contents. The project culminates in the design, assembly and burial of a 'smart' pipe demonstration unit, comprising a length of standard water pipe, with sensors and a Smart Server prototype positioned along its length. The Smart Server transmitted the sensor signals to the surface-level monitoring equipment, whereupon the expected responses were obtained to changing conditions, eg temperature, force and acceleration.

National Underground Assets Group: Defining the Technological Capability Necessary for Sharing and Displaying Asset Information - User Requirements

Ref: 08/WM/12/23            Price: £15
ISBN: 1 84057 507 7

This report sets out the validated User Requirements for Sharing and Displaying Asset Information through a web-based service as part of the proposed NUAG Approach. It has been produced by the National Underground Assets Group (NUAG), an organisation representing all key stakeholder groups, including appropriate Government departments, and is based on an extensive Focus Group exercise involving experts representing utility, highway, contractor and surveyor organisations.
The NUAG Approach, described in the NUAG Report: A national approach for capturing, recording and sharing underground asset information (07/WM/12/19), forms the basis of a national high-level framework to deliver a set of minimum performance standards, all based on identified stakeholder requirements described in the NUAG Report: Capturing, recording, storing and sharing underground asset information, A review of current practice and future requirements (06/WM/12/13).

Mapping the underworld: Sensor Technologies - Review and Progress

Ref: 08/WM/12/21            Price: £20
ISBN: 1 84057 477 1

Mapping The Underworld is an EPSRC funded programme consisting of 4 projects and a dissemination network, which was originally initiated by UKWIR under the 'Minimising Streetworks Disruption' programme. One of the projects, running for a year, investigated the feasibility of new approaches to locating buried assets. These approaches included different configurations for GPR and acoustic technologies as well as new electro-magnetic technology. The report details the findings during the year and includes proposals for futher work to develop a test location for buried asset location equipment as well as plans to develop the technology to a prototype machine.

Minimising Street Works Disruption: Data Integration and Display - Mapping the Underworld Seminar April 17th 2007

Ref: 08/WM/12/22            Price: £13
ISBN: 1 84057 476 3

Mapping The Underworld is an EPSRC funded programme consisting of 4 projects and a dissemination network, which was originally initiated by UKWIR under the 'Minimising Street Works Disruption' programme. The dissemination network was set up with the intention of holding workshops every 6 months to disseminate the output from the research programme and identify directions for future research. The third workshop was held in April 2007 and focussed on the work done in one of the projects and the related DTI funded 'VISTA' project. This work is investigating ways to integrate the wide variety of utilities' data and display it in a readily understandable format. The report gives details of the presentations and subsequent discussions from that workshop.

Minimising Street Works Disruption: Mapping Technologies for Buried Asset Location - Mapping the Underworld Seminar September 14th 2006

Ref: 08/WM/12/20            Price: £11
ISBN: 1 84057 478 X

Mapping The Underworld is an EPSRC funded programme consisting of 4 projects and a dissemination network, which was originally initiated by UKWIR under the 'Minimising Streetworks Disruption' programme. The dissemination network was set up with the intention of holding workshops every 6 months to disseminate the output from the research programme and identify directions for future research. The second workshop was held in September 2006 and focussed on the work done within one of the projects and the related Dti funded 'VISTA' project to investigate new and improved techniques to map buried assets. This report gives details of the presentations and subsequent discussions from that workshop.

National Underground Assets Group: A National Approach for Capturing, Recording, Storing and Sharing Underground Asset Information

Ref: 07/WM/12/19            Price: £25
ISBN: 1 84057 454 2

This report sets out a new common approach to capturing, recording, storing and sharing underground asset information that offers significant benefits to all stakeholders.  It has been produced by the National Underground Assets Group (NUAG), an organisation representing all key stakeholder groups, including appropriate Government departments.  The approach has been developed by experts representing utility companies, highway authorities, contractors, surveyors and IT specialists, based on regular and extensive stakeholder engagement.
The NUAG Approach forms the basis of a national high-level framework to deliver a set of minimum performance standards, all based on identified stakeholder requirements described in the NUAG Report: Capturing, recording, storing and sharing underground asset information, A review of current practice and future requirements, published in September 2006

Outcomes of the ORFEUS Questionnaire

Ref: 07/WM/12/18            Price: £14
ISBN: 1 84057 452 6

The European Commission has recognised the potential for plant location technology to safeguard the environment and, under the Sixth Framework Programme (Global Change and Ecosystems), is supporting the ORFEUS project (Optimising Radar to Find Every Utility in the Street) which aims to improve the performance of surface deployed GPR, and develop a new radar to provide a look-ahead capability for Horizontal and Directional Drilling equipment.  This report describes the process used, and results from, a stakeholder survey designed to ensure the development of a Specification for new technologies that most closely meets the requirements of users of location technologies and services.

Minimising Street Works Disruption: GPR In Sewers

Ref: 07/WM/12/16            Price: £15
ISBN: 1 84057 448 8

Within the 'Minimising Street Works Disruption' programme one project, (C2) identified that a possible way to capture buried asset information was utilise GPR within buried conduits such a sewers. A project was therefore initiated to trial the use of GPR within sewers. The trial was not successful due to the problems of locating a suitable sewer and providing a GPR unit which complied with the heath and safety regulations. Nevertheless valuable information was collected about the feasibility of such an approach. This report details the procedures followed to attempt the trial and the information collected as a result.

Minimising Street Works Disruption: Sensors for Buried Asset Location - Mapping the Underworld Seminar, April 26th 2006

Ref: 07/WM/12/15            Price: £13
ISBN: 1 84057 447 X

Mapping The Underworld is an EPSRC funded programme consisting of 4 projects and a dissemination network, which was originally initiated by UKWIR under the 'Minimising Street Works Disruption' programme. The dissemination network was set up with the intention of holding workshops every 6 months to disseminate the output from the research programme and identify directions for future research. The first of these workshops was held in April 2006 and focussed on the work done within one of the projects to carry out feasibility studies of new and improved techniques to locate buried assets. This report gives details of the presentations and subsequent discussions from that workshop. 

National Underground Assets Group: Capturing, Recording, Storing and Sharing Underground Asset Information - A Review of Current Practice and Future Requirements

Ref: 06/WM/12/13            Price: £25
ISBN: 1 84057 422 4

The National Underground Assets Group is sponsoring the National Referencing Standards Project, Phase 1 of which aims to develop methodologies, standards and best practices that address the short-term standardisation needs to 2008, for capturing, recording, storing and sharing underground asset information. This report makes a series of recommendations for a mandatory revised Records Code of Practice, and a mandatory national standard high-level framework to enable effective deployment of the new Code, based on a User Survey of a representative sample of utilities and highway authorities.

The Implications of the Traffic Management Act

Ref: 06/WM/12/12            Price: £10
ISBN: 1 84057 413 5

This project reviewed the impact of the Traffic Management Act (TMA) on water companies and identified ways to mitigate its impact and prepare for discussions with Ofwat. The report provided an overview of the TMA and its secondary legislation at the time of writing and will assist utilities with the substantial effort in preparing for the implementation of the TMA.

It has identified a range of measures to mitigate the impact of the Act and laid the essential groundwork that will facilitate any approach to regulators.  It will allow organisations to make a local assessment of the most serious impacts of the TMA and benchmark themselves against the impact on the water industry nationally as described in the report.

Minimising Street Works Disruption: Progress 2002 - 2006

Ref: 06/WM/12/10            Price: £11
ISBN: 1 84057 410 0

The Minimising Street Works Disruption programme, consisting of 15 projects valued at £10 million, was developed following a 2 day seminar attended by representatives from a wide variety of utilities from the UK, US and Netherlands. Since that time, there has been progress with all but 2 of the projects. This report details that progress and the status of the different projects.

Minimising Street Works Disruption: Buried Asset Data Collection and Exchange Field Trials

Ref: 06/WM/12/9            Price: £14
ISBN: 1 84057 409 7

The Minimising Street Works Disruption programme identified 15 projects under four overall headings, the first of which looked at how work could be improved just by making better use of current technology. Within this group of projects, one project was identified to look at best practice for existing buried asset location technologies.

This report details the results of trials in North London and Yorkshire which trialled the various methods of data capture for buried assets including traditional methods such as tape measures and trundle wheels as well as the latest satellite survey equipment. It also looks at the current methods of exchanging and collating utility asset data used by contractors to the water industry.

Minimising Street Works Disruption: The Real Costs of Street Works to the Utility Industry and Society

Ref: 05/WM/12/8            Price: £16
ISBN: 1 84057 408 9

The Minimising Street Works Disruption programme identified 15 projects under four overall headings, the first of which looked at how work could be improved just by making better use of current technology. Within this group of projects, one project was identified to develop a better understanding of what street works cost the utility industry and what they cost society in general.

This report details the results from that project. It reviews literature on the subject and endeavours to estimate both the direct cost of street works to utilities and the costs of street works to society. It identifies the ways in which these costs can be minimised as well as gaps in knowledge requiring further research.

Underground Asset Location: Review of Current Technology

Ref: 05/WM/12/7            Price: £10
ISBN: 1-84057-369-4

This report presents high-level requirements for underground asset location and summarises the current state of the art in the location of underground assets. It recognises that the majority of effort in this area is focussed on the optimisation of these technologies and that there is little innovation in terms of new sensors and therefore reviews other disciplines as diverse as medicine, defence, archaeology and space to identify a broad spectrum of new technologies which could potentially be harnessed to address this issue.

Minimising Street Works Disruption Stakeholders Forum 21 June 2004

Ref: 04/WM/12/6            Price: £10
ISBN: 1-84057-337-6

There is no abstract for this report.

Locating Underground Plant and Equipment - Proposals for a Research Programme

Ref: 03/WM/12/4            Price: £11
ISBN: 1-84057

Following research in the UK and US that indicated shortfalls in performance of current technologies, and the need for improvements, an international workshop attended by a group of experts from the UK, US and the Netherlands, representing utilities, contractors, manufacturers, research organisations and academia, identified potential research opportunities to address identified problems, shortfalls and needs. These have been developed into a research programme. This report details the proposals for this research programme.

Locating Underground Plant and Equipment - Overview of Proposals for a Research Programme

Ref: 03/WM/12/3            Price: £10
ISBN: 1-84057

Following research in the UK and US that indicated shortfalls in performance of current technologies, and the need for improvements, an international workshop attended by a group of experts from the UK, US and the Netherlands, representing utilities, contractors, manufacturers, research organisations and academia, identified potential research opportunities to address identified problems, shortfalls and needs. These have been developed into a research programme. This report provides an overview of this research programme.

Multi-Utility Buried Pipes and Appurtenances Location Workshop, London, 29-31 May 2002

Ref: 02/WM/12/2            Price: £14
ISBN: 1-84057-282-5

This report describes a workshop, sponsored jointly by UKWIR and AwwaRF, held on 29th to 31st May 2002, that addressed the issues surrounding the location of multi-utility buried pipes and appurtenances. The workshop culminated in a set of sixteen detailed research proposals with plans for their further development.

Report on Asset Location and Condition Assessment

Ref: 02/WM/12/1            Price: £24
ISBN: 1 84057 274 4

This report reviews the techniques that are currently available for underground asset location and for the condition assessment of the buried infrastructure.  It has been produced following significant revision and expansion of a review produced as part of the EPSRC Engineering Programme Network in Trenchless Technology (NETTWORK).  NETTWORK aims to bring all relevant UK academics and industrialists together to synthesise knowledge in the broad field of trenchless technologies, agree the research needs, disseminate this information as widely as possible and formulate research proposals to address these needs (NETTWORK, 2001).

This review of pipeline location technology and condition assessment aims to provide details of the essential technology that is currently available for use in practice, as opposed to citation of case histories of the use of the technology.

Maintenance continuing serviceability

Treated Water Storage Assets: Good Practice for Operation & Management Version 2

Ref: 19/RG/05/50            Price: £150
ISBN: 978-1-84057-871-3

The purpose of this project is to provide water companies with good practice guidance for the whole life management of the construction, refurbishment, repair, operation and maintenance of treated water storage assets. Such guidance is mapped to the UKWIR Framework for Expenditure Decision Making in order to help asset managers, operators and capital investment planners better inform investment decisions to manage water quality risks.

The project was developed in conjunction with significant industry engagement, through two industry workshops involving representatives from UK Water Companies, Regulators, Academia and Industry, and five water company interviews. 

The project deliverables consist of:

  • a guidance document summarising good practices for the inspection, operation, maintenance, refurbishment, repair and new construction of treated water storage assets; and
  • a complementary spreadsheet toolkit illustrating a process to support investment planning activities for treated water storage assets through a condition assessment, deterioration and risk modelling approach.

Please note that this report – ‘Treated Water Storage Assets: Good Practice for Operation and Management – Version 2’, reference number - 19/RG/05/50 replaces the previous version (17/RG/05/48). The majority of the revisions made are to the sections on ‘external roof membranes (section 10.11)’ and ‘intelligent membranes (section 13.4.4)’ plus the associated table in Appendix 5. Please destroy or delete any copies of the previous version of the report that you have.

We apologise for any inconvenience this may cause.

Metering

The Effect of Pressure on Meter Accuracy

Ref: 00/WM/10/3            Price: £12
ISBN: 1 84057 179 9

A number of small diameter revenue meters have been tested to ascertain if pressure has any influence on meter accuracy. A selection of new meters were tested over a range of flows and pressures. No evidence could be found in the limited number of tests undertaken that there is any relationship between pressure and meter accuracy between 1 bar and 10 bar.

Pipeline Innovation

A Review of Wastewater Instrumentation, Automation and Control

Ref: 14/WM/02/21            Price: £100
ISBN: 1 84057 740 1

Water companies face ongoing pressures to improve operational and asset management efficiencies and deliver the same service for less cost. Equally, ever tightening regulations and wastewater compliance requirements mean water companies may need to improve treatment processes and ensure more consistent outputs. Instrumentation, process controls and data and information management could play a key role in achieving this.

With plans to invest circa £500m during AMP6, companies need to invest wisely in instrumentation and avoid legacy problems. The objectives of the study included developing an understanding of the industry's long term drivers and objectives; an evaluation of the state of the industry in terms of instrumentation, process control and automation; and an evaluation of what is available on the market such that the gaps between these can be identified.

This study is based on a series of interviews with key stakeholders within water companies and the supply chain.

Strategic Lead Communication Pipe Replacement: Initial Review of Water Company Pilot Trials

Ref: 05/WM/02/20            Price: £13
ISBN: 1-84057-376-7

This report summarises the results from five pilot studies to develop and test methodologies for strategic lead communication pipe replacement programmes. The studies are the first of 12 which were agreed with DWI and initiated during the AMP3 period. The sources of information were reports on each of the studies produced by the companies Anglian Water, United Utilities and Yorkshire Water. It is hoped that   this summary report will enable the learning gained from the studies to be  widely disseminated at the earliest opportunity and used to inform the further development of company strategies.

Understanding Burst Rate Patterns of Water Pipes

Ref: 01/WM/02/16            Price: £16
ISBN: 1 84057 242 6

A range of different water companies have supplied UKWIR with their pipe burst data for the last few years and these have been combined into one �national� database. The level of detail in some of the data from smaller companies is very good and this has combined well with the large numbers of bursts recorded by the big PLCs.

Plastics Pipeline Systems - Pipeline Innovation

Ref: 97/WM/02/3            Price: £36
ISBN: 1 84057 031 8

The programme in 1996/1997 has address a wide range of issues relating to the design and specification of new plastics pipes and fittings which now form the basis of new distribution mains and rehabilitation techniques. By virtue of new work, the highly conservative surge and fatigue design criteria have been relaxed for tough PE materials and de-ratings for all other materials have been established. Tests have been conducted on a range of new PE materials to allow for greater competition and thus reduce pipe costs. The performance criteria for the specification of PE pipes and electrofusion fittings have been developed and work has been carried out on the impact criteria for structured wall sewer pipes. It has been shown that it is possible to use recycled material from surplus pipe from construction sites to make new wastewater systems. A failure analysis service has been operated which has led to the early identification of potential future problems - largely with fittings. Actions to rec

Rehabilitation Strategy

Ref: 01/WM/02/18            Price: £16
ISBN: 1 84057 244 2

Since 1989, Water Mains Rehabilitation Strategy in the UK has been predominantly focussed on meeting regulatory targets in the area of water quality. Renovation technique selection has been driven mainly by price and politics rather than robust engineering.

Evaluation of Welding & Jointing of Plastic Pressure Pipes

Ref: 01/WM/02/15            Price: £15
ISBN: 1 84057 240 X

Welding criteria for PE systems have been evaluated by analysis of thermal data to try to reduce heating/cooling cycles and thus speed up jointing where butt fusion is used. A new harmonised set of welding conditions have been evolved which should allow the same conditions to be used for both gas and water pipe installations. Also, the new ‘Fastweld’ process which allows for reduced has been thoroughly investigated and new conditions devised to allow reduced cycle welds to be made with the same physical conditions as standard joints. Welds made in a full range of PE80 and PE100 pipes from 90mm to 400mm diameter have been tested at both 20°C and –5°C. The toughness of welds has been found to be satisfactory for all wall thicknesses up to 30mm. A full assessment of the welding properties of ‘Profuse’ PE pipe with an external PP skin has been made. Jointing of the pipe has been found to be totally satisfactory by both butt fusion and electrofusion welding. With electrofusion fitti

The Residual Structural Properties of Cast Iron Pipes – Structural and Design Criteria for Linings for Water Mains

Ref: 01/WM/02/14            Price: £20
ISBN: 1 84057 239 9

The options for relining of old cast iron water mains depend crucially on the perceived condition of the old pipe. All the pipe condition databases which are known to exist in the UK have been combined to give an appreciation of the rates of internal and external corrosion of old cast iron pipes. Also, pipe burst databases have been analysed to check on the prime modes of pipe failure. From these analyses, it is concluded that the growth of corrosion pits to cause holes to develop in the wall of the pipe is not the prime cause of failure. Rather old iron pipes fail when there are ground movements which cause bending moments to be applied which then cause the pipe to crack. The origins of the cracks are corrosion pits which act as stress concentrations. These pits need not necessarily have grown all the way through the pipe wall. In such cases, the projected residual lifetimes based on simple wall penetration will be optimistic. The other major problem in forecasting lifetimes based on corrosion growth is that

Plastics Pipeline Systems Evaluation of Long- term Performance – The Behaviour of Buried Pipes

Ref: 97/WM/02/5            Price: £10
ISBN: 1 84057 038 5

Details the loads, temperatures and effects of the soil on two sections of 250mm continuously monitored PVCu pipe and assesses the changes in performance of an exhumed MDPE pipe. Indicates that design criteria are conservative and recommends that the conclusions should be included in installation specifications.

PE Pipes for Contaminated Land

Ref: 99/WM/02/9            Price: £13
ISBN: 1 84057 152 7

The permeation resistance of the new “twin walled” PE/ Aluminium or PE/ polyamide pipes and the effect of organics on various rubbers have been investigated. A polyamide outer layer extruded over standard PE pipe can reduce permeation of solvents but will not be effective in all situations. Inclusion of an aluminium layer into the main PE wall structure prevented the permeation of unleaded fuel through the PE pipe. Thus, this type of pipe provides a solution for cases where the contamination is severe (or unknown). A testing protocol for the assessment of the barrier characteristics to ‘unknown solvent cocktails’ has been developed. The behaviour of elatomeric seals for pipes joined by socket and spigot systems needs consideration if pipe is laid in contaminated land. In laboratory tests, Viton rubber has been found to be the most resistant to diesel and unleaded fuels, but nitrile rubber can be effective in some circumstances.

Performance of Fast Butt Fusion Jointing

Ref: 99/WM/02/7            Price: £10
ISBN: 1 84057 150 0

A high productivity butt fusion welding process has been developed by Fusion Group. The process was evaluated on PE80 and PE100 pipe materials in sizes up to 400mm and compared against butt fusion joints prepared under conventional Water Industry conditions. It was found that there was a threefold increase in productivity with all joints failing in a totally acceptable ductile manner. However, the short soak time of the process resulted in significantly reduced weld beads and it was felt there was less scope for pushing out potential contamination from the weld interface. Modified conditions were developed for PE80 pipe that combined the productivity benefits with the weld bead sizes and performance characteristics of conventional butt fusion joints. Similar modified welding conditions were applied to PE100 pipe but this found to be less successful.

Performance of Access Chambers

Ref: 99/WM/02/13            Price: £12
ISBN: 1 84057 156 X

Plastic materials are increasingly being offered as alternative materials to concrete for manufacturing chamber units for the installation of valves and hydrants. The units vary in size and construction but ultimately their virtue lies in their lightweight nature and simplicity of installation. An appraisal of the structural integrity of plastic access chambers has been conducted in laboratory and site monitored tests with a view to extend their range of application to highways. The performance of the units to imposed vertical and lateral loadings was evaluated. From the results of extensive tests, the long term design limits for each type of construction has been defined. It was found that only the stiffest plastic units based on the thicker sections were capable of withstanding the effects of large wheel loads of highway traffic.

Evaluation of Long Term Performance the Behaviour of Buried Pipes

Ref: 99/WM/02/12            Price: £11
ISBN: 1 84057 155 1

Monitoring of buried PVCu and thin wall biaxially oriented pipe at Chorley and York has shown that loads and deformations of the pipe are predominately generated during installation and that subsequent transient traffic loads produce no permanent changes. Measurements of backfill temperatures have shown long time lags between changes in surface temperature and those at pipe depths. Data from monitoring pipe laid at shallow depths and from laboratory tests have demonstrated that water temperature dominates the pipe environment. The site measurements show no evidence of freezing in mains laid with 750mm cover. Projections show that very prolonged periods of cold weather would be required to freeze water in plastics mains. The behaviour of shallow service pipes is being monitored.

Evaluation of the Resistance to Collapse of Thin Walled Liners

Ref: 99/WM/02/11            Price: £12
ISBN: 1 84057 154 3

In the design of thin walled liners, the resistance to external pressure resulting from internal vacuum or external water table must be considered. It is the primary design criterion for thin-wall cured-in-place sewer linings. Laboratory tests on four different types of pipe material have demonstrated that the collapse pressures for unrestrained pipe are accurately predicted by the standard analytical solution. There is considerable enhancement of the collapse pressure in liners constrained from deformation by a host pipe. The degree of enhancement is dependent on the SDR of the pipe and is markedly affected by the presence of small folds or annular gaps between liner and host pipe. Excellent agreement has been obtained between predictions of the effects of gaps on collapse using a computer model and tests on PVCu and PE liners inside steel pipe. Design tables for common in- service situations have been produced.

Performance of Electrofusion Joints for PE Pipes

Ref: 99/WM/02/10            Price: £10
ISBN: 1 84057 153 5

The large number of service failures of electrofusion joints remains of prime concern to UK water industry. This investigation combines the findings of two year's work looking at the effects of site conditions, joint preparation and fitting type on joint performance. A large round robin exercise was conducted with the involvement of all manufacturers to look at the effects of wet wipes on joint performance. Different wipe formulations were compared and it was found that their effects were negligible relating only to the rate of evaporation from the cleaned surface The tolerance to contamination test developed for couplings was extended for large diameter couplings and modified for tapping tees. A performance variability between manufacturers to overcome the effects of joint contamination clearly exists.

Pipeline Innovation - Final Report - 1995/ 96

Ref: 96/WM/02/2            Price: £20
ISBN: 1 84057 114 4

Summarises the 1995/ 96 developments in pipeline innovation. Includes identification of the main causes of plastic pipe failures from a new national database. Reports research progress on design against surge and fatique, interaction of pipe and backfill, use of thin walled pipes for relining and polyethylene pipe recycling. Assesses site pressure tests, performance of electrofusion fittings and new high performance pipes.

Pipeline Technology

Assessing the Structural Condition of PVC Pressure Mains

Ref: 15/WM/04/11            Price: £350
ISBN: 1 84057 786 X

The water industry has a significant stock of PVC-U, PVC-O and PVC-A pressure mains some of which are now approaching the end of their 50 year design life. Additionally, early generation PVC-U mains have been shown to have a higher failure rate than anticipated.

This report sets out a description of the failure mechanisms of PVC pipes, reasons for their premature failure and describes the various methods of testing the mechanical characteristics of existing PVC pipe materials.

The report also investigates the various NDT methods that could be used to assess the condition of these pipes and provides guidance on future avenues of research that could be pursued in this area.

Air Valve Management

Ref: 13/WM/04/10            Price: £32
ISBN: 1 84057 703 7

Techniques for Preventing Interruptions to Customer Water Supplies

Ref: 12/WM/04/9            Price: £13
ISBN: 1 84057 630 8

Customer expectations in terms of quality of service are rising; as such, customers are increasingly intolerant of interruptions to their water supplies. This increasing expectation is reflected in the introduction of the Service Incentive Mechanism and the requirement for more detailed reporting of interruptions to Ofwat. The water industry has developed a number of methods for working on mains under pressure to prevent interruptions, but there is a wide difference in the application of these techniques across the industry. This report evaluates the under pressure techniques that are currently available to the water industry, as well as reviewing those used in the Oil and Gas industry to assess what new techniques could be developed. A Decision Support Tool has also been developed to assist the practitioner in determining the relative cost effectiveness of under pressure techniques versus conventional methods, taking into account the impact of causing interruptions.

The Effect of Pressure Reduction on Burst Frequency

Ref: 12/WM/04/8            Price: £12
ISBN: 1 84057 618 9

This project investigated the effect of pressure reduction on repair rates by looking at historical data on a DMA basis.
It was concluded that implementation of pressure management generally results in a reduction in the number of repairs in subsequent years by up to 15%. Pressure management is most likely to be beneficial in terms of repair rate when the pre management rate is greater than 1.1 repairs/km/year. The results of this work are consistent with the IWA 'tipping point' hypothesis.

Fire Hydrants & Fire Fighting Supplies

Ref: 10/WM/04/7            Price: £22
ISBN: 1 84057 565 4

Issues surrounding fire hydrants and fire fighting systems have been a long-standing concern to water companies, Fire & Rescue Services and the sprinkler industry. This project's objectives were to identify potential improvements to national guidance documents and establish how existing protocols and funding arrangements for hydrant provision, safeguarding, repair and removal could be improved. An integrated consultation and communications strategy and programme was devised and implemented.
The National Liaison Group on Fire Fightling Activities (NLG) will be requested to oversee the implementation work, retaining overall control but delegating some of the practical work to relevant organisations. There are 4 strategic and 22 detailed recommendations for implementing the outcomes of the research project. The strategic recommendations are: that the NLG be invited to take overall responsibility for the implementation of the recommendations and actions contained in the report; production of a short briefing paper for government outlining the consultation, issues and proposed solutions; meetings with departmental contacts at CLG and Defra; ministerial and political briefing papers and meetings.

21st Century Distribution Networks

Ref: 10/WM/04/6            Price: £29
ISBN: 1 84057 551 4

The water industry, in contrast with other utilities, has a significant number of very long-life assets. This project looks at drivers which will affect the design of distribution systems over the next 70 years as this represents a period of time over which a radically different water distribution system could evolve.
A 'scenario planning' approach is used with a range of alternative futures considered; each of these futures requires differing responses in order to ensure a sustainable water distribution service is delivered. Importantly, through direct discussions and project workshops, the major stakeholders in the water sector helped shape the outputs of the project. The result is a 'wide ranging' review of the water distribution service to help the industry focus on standards, operational approaches, technologies and structures which may be required to meet the challenges arising over the next 70 years. Short, medium and long term issues have been considered with recommendations for research.

Code of Practice for Self-laying Water Mains and Services - Final Report

Ref: 04/WM/04/3            Price: £10
ISBN: 1 84057 366 X

Summarises the work carried out under the UKWIR project 'Code of Practice for self-laying water mains and services'. The report describes the drafting and consultation processes in developing the Code.
The Code of Practice is to be published by WRc. Recommendations are made for its ongoing maintenance, the use of a website to hold company-specific addenda to this Code and guidance for the preparation of such an addendum.

Mains Location Equipment A State Of The Art Review and Future Research Needs - Final Report

Ref: 01/WM/06/1            Price: £16
ISBN: 1 84057 233 7

The report examines the equipment currently used for the location of utility buried services and reports upon performance, based upon a limited assesment carried out on two trials sites. The actual performance achieved is compared with the expressed requirements of the water utilities. The need for performance specifications and a better understanding of the limitations of current equipment are identified, together with the needs for future research and development.

Pipe Isolation Techniques : Cost Benefit Assessment of Available Methods

Ref: 96/WM/04/1            Price: £14
ISBN: 1 84057 115 2

Isolation of pipelines can reduce cost and customer disruption compared to conventional valve closures. Using a theoretical cost model, estimates the costs of isolation systems, such as pipe freezing, pipe squeezing and line stopping. Compares costs with the expected valve closure method. Reviews equipment available and methods of use and reports water company attitudes.

Guidance for the Selection of Water Supply Pipes to be used in Brownfield Sites

Ref: 10/WM/03/21            Price: £50
ISBN: 1 84057 569 7

With an increasing number of brownfield sites being used for development, it is important that appropriate water supply pipes are selected to provide long term protection to both water quality and structural integrity of pipes. The focus of this project is the development of clear and concise procedures which provide consistency in the pipe selection decision process. Published data and water industry experience on the impacts of different contaminants on pipe materials have been used to provide guidance that can be used by relevant parties to ensure compliance with current regulations; and to prevent water supply pipelines failing prematurely due to the presence of contamination.

Managing the Risks Presented by Pipeburst, Redundant and Live Asbestos Cement Pipe Water Distribution Mains: Estimation of the Costs Associated with Different Rehabilitation Techniques

Ref: 04/WM/03/19            Price: £10
ISBN: 1-84057-382-1

The objective of this study was to estimate the relative costs of each rehabilitation option in order that all acceptable options (with respect to risk) can be compared financially.

Standard Ofwat costs (benchmark and mid point) were used to determine the relative costs of five rehabilitation techniques. These costs were for all materials, consequently, additional costs specific to asbestos cement pipes were identified and listed.

The costs given are the lowest value due to the nature of the Ofwat costs, and are likely to underestimate the true costs. Conclusions and recommendations are also made.

 

Managing the Risks Presented by Pipeburst, Redundant and Live Asbestos Cement Pipe Water Distribution Mains: Condition Assessment Methodology for Asbestos Cement Pipes

Ref: 04/WM/03/18            Price: £16
ISBN: 1-84057-381-3

The objective of this study was to develop a methodology for predicting the condition of AC water pipes and identify how GIS could be used to report this information.

Each of the factors affecting condition of pipes are identified and a model developed to predict degradation. The model is correlated against field samples tested at WRc using phenolphthalein tests and crush tests.

The study concluded that the strength of an AC pipe can be correlated to wall thickness. Maximum observed rates of internal and external degradation are calculated.

 

Managing the Risks Presented by Pipeburst, Redundant and Live Asbestos Cement Pipe Water Distribution Mains: Risk Assessment of Asbestos Fibre Release During Rehabilitation of Asbestos Cement Water Ma

Ref: 04/WM/03/17            Price: £17
ISBN: 1-84057-380-5

The objective of this study was to derive quantitative values for asbestos fibre concentrations released by a range of rehabilitation options and a range of conditions. These data would be incorporated into the qualitative risk assessment model developed during an earlier UKWIR project 'Risk assessment for the replacement of asbestos cement water distribution pipes' (ref no 02/WM/03/8) to validate the conclusion reached in that report that decommissioning and pipe bursting represent lower risk options than removal.

Air monitoring at two pipe bursting sites was undertaken and the concentration of respirable asbestos fibres released was measured. Also, samples of asbestos cement pipes were crush tested and the concentration of asbestos fibres released was measured.

Quantitative values for respirable asbestos fibre release were incorporated into a quantitative risk assessment model to estimate the comparative respirable asbestos fibres release concentrations for the decommissioning, pipe bursting and open-cut removal techniques.

The study concluded that the open-cut removal technique demonstrates a higher risk of respirable asbestos fibre release than the decommissioning and pipe bursting techniques.

 

Managing the Risks Presented by Pipeburst, Redundant and Live Asbestos Cement Pipe Water Distribution Mains: Project Summary Report

Ref: 04/WM/03/16            Price: £10
ISBN: 1-84057-379-1

The objective of this report was to summarise the work carried out in the complete project and update the water industry on legislation. This report provides a useful introduction to the 3 more detailed reports from this project covering:
 - Field trials
 - Risk Assessment
 - Condition Assessment
 - Cost of rehabilitation options

 

Risk Assessment for the Replacement of Asbestos Cement Water Distribution Pipes

Ref: 02/WM/03/8            Price: £18
ISBN: 1 84057 418 6

This report assesses the impact of Regulations on working with asbestos cement pipe, the risks associated with the various options for rehabilitation or replacement, and the impact on the environment (groundwater and landfill) of the various options. Legislation with respect to Health and Safety and the disposal of waste conflict in their requirements on dealing with asbestos-containing products. Consequently, the choice of abandonment (leading to the creation of hazardous waste) or removal (creating airborne fibres and the problem of a significant reduction in the number of available landfill sites) needs to be assessed against the risks.

Epoxy Resin - Blistering of Linings

Ref: 01/WM/03/6            Price: £10
ISBN: 1 84057 232 9

A range of laboratory tests have been conducted to assess the propensity of current epoxy resins to form blisters and establish the cause(s) of such blistering when used to line cast iron pipes. Although the results of such trials were inconclusive, the tests investigated most of the factors believed to cause blistering and demonstrated that there is no mechanism that can consistently be shown to be the cause. A Code of Practice highlighting improvements to the current regulatory documentation and instigating best working practice has been drafted, and will form the basis for a new Operational Guidelines and Code of Practice document that will be published in Autumn 2001.

Epoxy Resin Linings - Development of a Water Industry Specification for Epoxy Resin LiningMaterials

Ref: 97/WM/03/1            Price: £18
ISBN: 1 84057 118 7

Gives the test results of five types of epoxy resin lining, with standard mis and /- 10% hardness. The tests are for long- term durability, salt spray, water erosion/ standard abrasion, blistering, shrinkage and efficiency of cure at low temperature. The suitability of the tests for inclusion in a Water Industry Standard (WIS) is discussed. Includes sixteen illustrative photographs.

Blistering of Linings

Ref: 01/WM/03/5            Price: £15
ISBN: 1 84057 218 3

PDL have conducted the first major study to investigate the causes of blistering by considering the fundamentals of the blistering phenomenon and conducting methodical investigation in the laboratory. The work has provided a far greater understanding of the blistering phenomenon including: · Better surface preparation improves adhesion and reduces blistering. · Faster curing resin may reduce blister size. · Some resin formulations are prone to gas evolution that may cause blistering. Further investigation of blistering in general or isolated service problems will benefit from the approach adopted and techniques developed by PDL.

Epoxy Resin - Small diameter distribution mains: Cutting, Drilling and Tapping

Ref: 97/WM/03/2            Price: £15
ISBN: 1 84057 009 1

Assesses three epoxy resin linings during various cutting, drilling and tapping operations on an in-situ water main. Demonstrates the inspection and assessment methods and records material performance. Evaluates and recommends working practices.

Epoxy Resin: Cleaning Large Diameter Pipelines for Epoxy Resin Lining

Ref: 97/WM/03/4            Price: £22
ISBN: 1 84057 033 4

Evaluates methods for cleaning large diameter pipelines in preparation for epoxy resin linings with regard to ease of use, practicality, cost and ability to improve adhesion and the potential to reduce blister formation. Recommends suitable cleaning methods and practices. Includes illustrative photographs of site trials.

Reinstatement

Re-use of Excavated Material in Trench Reinstatements in the Highway

Ref: 95/WM/01/9            Price: £11
ISBN: 1 84057 108 X

The policy and practice of material re-use for highway reinstatement are investigated.  Although, in some cases, cost savings can be obtained through greater material re-use this needs to be considered against possible premature failure.  Approaches to the use of such material are described.  The report provides a basis for water companies to review the use of excavated material and consider whether changes would be beneficial.

Re-use of Excavated Material

Ref: 96/wm/01/20            Price: £13
ISBN: 1-84057

Examines the processing methods at reinstatement sites for excavated material.  Cohesive, granule and cohesive/granule materials were prepared with a range of moisture content, varying the quantity of added quicklime.  These were tested using two types of rotovation equipment.  Details re-use compaction and re-processing costs as well as the overall economics.  Discusses health and safety aspects.

Shallow Installation of Water Pipelines

Ref: 97/WM/01/38            Price: £16
ISBN: 1 84057 117 9

Considers the advantages of shallow burial of water mains and service pipes. Investigates the effect of frost penetration on reduced cover depth. Gives potential cost savings of shallow burial and observes the effect of shallow installation on other services within the footpath.

Cold- Lay Material Compaction: Final Report

Ref: 97/WM/01/37            Price: £17
ISBN: 1 84057 023 7

Investigates the effectiveness of permanent cold-lay surfacing materials for reinstatement of highway openings. Assesses the suitability of a range of compaction equipment around surface boxes for both cold-lay basecourse and wearing course surface materials.

Reinstatement of Road Markings

Ref: 97/WM/01/35            Price: £15
ISBN: 1 84057 021 0

Examines road-marking products, their cost and whether they meet the current performance specifications on erosion, spread, skid resistance value, luminance factor and retro-reflectivity. Assesses how they perform at the end of the two or three year guarantee period.

Performance of Edge Cutting and Sealing Methods

Ref: 98/WM/01/41            Price: £14
ISBN: 1 84057 143 8

A review was made of the edge cutting and sealing methods currently in use for the reinstatement of vertical edges of highway openings. The Norton Clipper wet floor saw and the Stihl hand-held saw were shown to be more effective than the other cutting methods used. The TRL trial showed that the cold and spray applied edge sealing products were fast and easy to use and produced a good quality finish. The tensile and shear bond strength of the sealants were tested in a controlled laboratory environment. These tests indicated that the sealants fail in different ways so care must be taken when selecting a sealant for use.

Performance of Foamed Concrete

Ref: 96/WM/01/19            Price: £9
ISBN: 1 84057 082 2

Forty five trench reinstatement sites were identified where foamed concrete had been used as sub- base, roadbase or a combination in the reinstatement. Describes the data collection exercise from utilities and highway authorities. No current problems were identified. Describes future work including further visits to sites and the establishment of a database.

Properties of Foamed lean Concrete

Ref: 96/WM/01/18            Price: £12
ISBN: 1 84057 081 4

Literature review of foamed concrete containing mixed aggregate. Gives the results of laboratory investigations on two trial mixes with four different densities. Analyses compressive strength/ density, development of compressive strength and, finally, durability through fifty 24 hour freeze/ thaw cycles.

Performance of Cold- Lay Surfacing Materials

Ref: 96/WM/01/17            Price: £11
ISBN: 1 84057 085 7

Reports on seven sites using cold- lay surfacing materials and also on twenty four panels on a test trrack, using four basic types of basecourse and wearing course materials. Gives information compliance with specifications to BS 4987. Gives elastic stiffness performance, over time, against HAUC Code of Practice target values.

Bituminous Reinstatements in Small Openings : Performance of Compaction Equipment

Ref: 96/WM/01/16            Price: £12
ISBN: 1 84057 109 8

Lists the compaction equipment available following a water industry survey and literature searches. Results are given for seven basecourse material compactors and three wearing course compactors using an in- house trial road. Gives details of ease of use and costs.

Bedding and Backfill for Small Excavations

Ref: 96/WM/01/15            Price: £11
ISBN: 1 84057 079 2

The HAUC Specification for reinstatement recognises the need for good compaction of backfill. However, standard GSB Type 1 contains large particules up to 37.5mm in size which prevent effective compaction in small openings. The aims of this project were to: investigate the performance of granular materials which could be used as both bedding and backfill in small excavations; develop a purchasing specification for these materials; and consider methods for testing the material on site to ensure that it meets the material description. A suitable material was identified which required less compaction than GSB Type 1, and a prototype specification is given. The study of test methods concluded that there are no simple on- site tests to confirm that a granular material complies with its specification, other than a visual assessment. The Dynamic Cone Penetrometer appears to offer a reliable way of assessing the compaction of granular material as it is being installed.

The Cost of Foamed Concrete and Grouts

Ref: 95/WM/01/8            Price: £10
ISBN: 1 84057 107 1

This report considers the initial costs of foamed concrete and cementitious grouts. It concludes that foamed concretes are economically available in all parts of the United Kingdom. Cementitious grouts are unlikely to be an economic alternative and have not progressed beyond the trial stage as reinstatement materials. Foamed lean concrete could be more economic to use than traditional foamed concrete, and the properties of foamed lean concrete need to be investigated.

The Specification of Foamed Concrete

Ref: 95/WM/01/7            Price: £10
ISBN: 1 84057 078 4

This report assesses users' views of foamed concrete as a reinstatement material, and aims to produce a workable specification for its use. Three areas of concern were expressed: the cost of the material, safety aspects immediately after laying, and the maximum permitted strength in the HAUC specification. It is recommended that the maximum permitted strength should be reduced. The notes for guidance presented in the report should be used for quality control purposes. The long- term performance of foamed concrete should be investigated.

Cold Laid Surfacing for Reinstatements

Ref: 95/WM/01/6            Price: £14
ISBN: 1 84057 106 3

This report describes trials of promising, cold- lay bituminous materials to evaluate and develop their suitability for water industry permanent reinstatement applications. The trials indicate that better quality control is required in the manufacture of cold- lay materials in order to ensure the consistent delivery of suitable material from a given supplier. The evidence is mixed regarding the stockpile life of the materials studied. The tests of the engineering properties have yet to be completed. If the performance of the materials warrants it, work may be needed on a new specification (other than the HAUC specification) particularly for elastic stiffness.

Damage to Highways by Leaks and Bursts

Ref: 95/WM/01/5            Price: £9
ISBN: 1 84057 077 6

Leaks and bursts can damage highways, and there are no procedures agreed by the water utilities and the highway authorities for assessing this damage. This project set out to review the legislation relating to damage caused to highways, and to develop procedures to assess this damage. It concluded that, under the New Roads and Street Works Act (NRSWA), it is no longer necessary to prove the water undertaker negligent before claims of compensation can be made. However, there have been few, if any, disagreements over damage to highways since the introduction of the NRSWA. There is a potential for idsputes to arise, so recommendaitons are given as to what information should be recorded in the event of a burst.

Delayed Backfill

Ref: 95/WM/01/4            Price: £9
ISBN: 1 84057 076 8

This project studied the effect of leaving excavations open longer than 24 hours. It was considered that excavations left open and unsupported might lead to subsidence and consequent damage to the road surface around the excavation. Water utilities were contacted regarding their policy on reinstatement, and a literature search conducted. It was found that water utilities are moving away from the practice of delayed reinstatement, so that it should not be a cause for concern in future.

Compaction around Narrow Trenches and Boxes

Ref: 95/WM/01/2            Price: £12
ISBN: 1 84057 105 5

This report investigates the overall performance of reinstatements around boundary boxes, valve chambers and within narrow trenches using various backfill and bedding materials. The project has demonstrated that: - It is possible to achieve satisfactory reinstatement of these features using currently available materials and equipment. Pneumatic pole tampers have been found to be particularly effective in restricted areas around boundary boxes. Foam concrete as the backfill material minimises the chance and magnitude of settlement of the reinstatement. The performance of reinstatements using granular backfill material depends upon the compaction achieved, the bedding material used and the way it is installed. The widely held assumption that pea gravel is self- compacting is incorrect.

A Guide to the Assessment of Road and Footway Condition for Reinstatement Purposes

Ref: 95/WM/01/14            Price: £13
ISBN: 1 84057 075 X

Effective site monitoring would enable utilities to identify and correct defects before the reinstatement is inspected by highway authorities. The objectives of this research therefore were (a) to provide guidance on the assessment of road and footway condition prior to trench excavation; and (b) to provide details of portable condition monitoring equipment so that non destructive test (ndt) methods can be utilised to determine construction depths. The research showed that there was a lack of knowledge of, and shortage of suitable equipment for reinstatement assessment.

Overbanding Materials for Trench Reinstatements

Ref: 95/WM/01/12            Price: £16
ISBN: 1 84057 104 7

Overbanding, whilst not a statutory maintenance treatment is important for two reasons: (a) to seal the material near the edge where it is difficult to achieve compaction; and (b) to prevent joint edge deterioration of new and existing materials. This research included supervised site trials to assess the effectiveness of various overband treatments. Objectives of the research were to examine whether the HAUC performance criteria could be achieved in practice. Other objectives concerned working practices, methods of trench reinstatement and the type of bituminous bound material used. From the preliminary results of the trials, all the binder only based products did not meet the current HAUC minimum skid resistance value (SRV). After six months, all the overbands which either contained grit (slurry seal) or had grit added to them maintained SRVs greater than 60. Further work is needed to determine whether the HAUC performance criteria can be maintained during the guarantee period.

A Supervisors Guide to Conventional Black Top Material Site Testing

Ref: 95/WM/01/10            Price: £12
ISBN: 1 84057 103 9

Guidelines and recommendations are provided for improving compliance and on- site acceptability for black- top materials at the point of delivery. By following such recommendations this Supervisor's Guide forms a reference document intended to provide an operational check- list for site testing and guidance to ensure common standards and good quality assurance are achieved.

Conventional Backfill - Final Report

Ref: 95/WM/01/1            Price: £9
ISBN: 1 84057 074 1

Foam concrete and grouts are now available to the water industry as an alternative to conventional backfill material. It is claimed that these new materials can achieve more reliable reinstatement, with less need to return and repair. The objectives of this project were therefore: to compare failure rates of conventional backfill with those of foam concrete and grouts; to produce a cost effective strategy for slecting backfill materials. Typical failure rates for reinstatement were not available. However, discussions with utilities that have used foam concrete indicate that reinstatements made with this material are less likely to fain than conventional backfill materials. The material costs for foam concrete are generally higher than for conventional backfill. However, cost savings can be made due to the reduced need to revisit reinstatements made with this material. Other cost savings may be achievable with foam concrete due to the reduced time of installation and therefore reduced labour costs.

The Performance of Foamed Concrete Reinstatements

Ref: 97/WM/01/36            Price: £15
ISBN: 1 84057 022 9

Assesses the performance of foamed concrete for reinstatements that have been in place over a number of years. Describes the establishment of a database of information on 65 sites from six utilities. Gives the results of an analysis of the data and discusses the implications. Lists the amendments to HAUC advice note 4.

Re- use of Excavated Material

Ref: 97/WM/01/29            Price: £29
ISBN: 1 84057 014 8

Builds on earlier UKWIR work (96/ WM/ 01/ 20) in developing a cost benefit analysis for comparing the processing of excavated material both on- site and at depots. Uses data from a water industry questionnaire. Gives the details of equipment available and describes and illustrates four depot demonstrations.

A Guide to Reinstatement Best Practice

Ref: 98/WM/01/40            Price: £44
ISBN: 1 84057 139 X

This document and its accompanying CD Rom bring together all the practical lessons learned from the UKWIR three year reinstatement research programme carried out by the Transport Research Laboratory (TRL). Written in simple "bullet point" form and illustrated with photographs, the Supervisors Guide is published in A5 format making it ideal for carrying in vans as a handy reference document for supervisors and operatives. The CD Rom version contains the same information and is ideal as a training tool.

Non- destructive in- situ Measurement of the Thickness & Density of Reinstatements – Final Report

Ref: 98/WM/01/39            Price: £10
ISBN: 1 84057 138 1

A review was made of NDT methods for the measurement of the thickness and density of reinstatement materials. Ground Penetrating Radar and Nuclear Density Gauges were considered to have considerable potential but are currently expensive and require further development. The most suitable technique currently available is the relatively inexpensive 'Staveley Test Kit' marketed by Errut Products Limited which removes small diameter cores from which the thickness and density of the surfacing material can be determined.

Highway Reinstatement : Barrier Systems

Ref: 96/WM/01/28            Price: £11
ISBN: 1 84057 085 7

Details the performance aims and desirable properties, current operational shortcomings and performance ratings of barriers from the results of a questionnaire to fifty two utilities, contractors and suppliers. Discusses and details Chapter 8 of the New Roads and Street Works Act compliance. Gives a prototype performance specification and an outline design together with diagrams and costings.

Highway Reinstatement - Temporary Hole Covers

Ref: 96/WM/01/27            Price: £10
ISBN: 1 84057 113 6

Surveys the performance of current temporary hole covers for small excavations in footpath and highways giving performance ratings and operational shortcomings. Gives a prototype performance specification and sets out the design. Considers costs and suitability for mechanical/ manual handling.

Shallow Installation of Water Pipelines

Ref: 96/WM/01/25            Price: £13
ISBN: 1 84057 084 9

This report examines the likely depth of frost penetration in the UK and the influence this may have on water mains and service pipes installed at 750 mm and 600 mm cover respectively. It also considers the effect of reduced cover depth on both standard fittings and other services within the footpath. Some of the conclusions the report draws are that: - It is not possible to predict with any certainty whether pipes will freeze at 600 mm or 750 mm because there is insufficient temperature information below 300 mm. The soil type and composition has an influence on the penetration of frost, but due to the variations in soil type and structure found in the UK, it is not possible to generalise on the depths to which frost might reach. Polyethylene pipes have a much slower rate of heat loss than equivalent iron and copper pipes and will therefore perform more favourably in severe winter conditions. It is possible for service pipes to be connected to the side of water mains, which will afford a better f

Reinstatement of Road Markings

Ref: 96/WM/01/24            Price: £14
ISBN: 1 84057 112 8

Assesses alternative products as to whether they meet current performance specifications and are likely to perform satisfacorily at the end of the guarantee period. Reviews UK practice associated with the small scale application of permanent road markings. Materials used for small scale reinstatements and their costs are assessed in laboratory scale and in- road site trials.

Overbanding Materials for Trench Reinstatements : Results after 12 months

Ref: 96/WM/01/23            Price: £11
ISBN: 1 84057 111 X

Gives results of twelve months monitoring at two sites using overbanding, a treatment for sealing joints around trench reinstatements and for sealing cracks. Considers the measurement of skid resistance value, texture permeability and the profile together with visual assessments. Reports the survey of current overbanding policy and practice by water companies. Discusses performance against HAUC specifications and gives interim guidance.

Deep Excavations: Compliance with the HAUC Specification and Long- Term Monitoring

Ref: 96/WM/01/22            Price: £10
ISBN: 1 84057 083 0

Gives details on the practice, including the permanent surfacing, at five deep excavation sites. Reports on their compliance with HAUC specifications. Describes the long term monitoring of these and five additional new sites and discusses reasons for non- compliance.

A Supervisor?s Guide for the Re- Use of Excavated Material

Ref: 96/WM/01/21            Price: £12
ISBN: 1 84057 110 1

Gives an operational checklist of the re- use of excavated material. Specifies the HAUC classes of material (granular, cohesive and granular/ cohesive) and gives the HAUC field identification tests. Identifies and describes typical problems giving options for dealing with material that is too dry or too wet.

A Code of Practice for Permanent Cold- Lay Surfacing Materials (PCSMs)

Ref: 97/WM/01/31            Price: £12
ISBN: 1 84057 017 2

Produces an operational check list of procedures that a supervisor should follow. Describes the background to PCSMs, lists typical problems encountered and sets out the HAUC requirements. Finally details the material sampling and the procedures involved in reinstatement.

Performance of Cold- Lay Surfacing Materials

Ref: 97/WM/01/30            Price: £12
ISBN: 1 84057 116 0

Builds on earlier UKWIR work (97/WM/01/17) in assessing the quality and suitability of cold-lay surfacing materials. Gives results of tests on four material types for material strength, permanent deformation and void content. Compares the results with HAUC Advice note 3. 40

A Code of Practice for Overbanding Treatments

Ref: 97/WM/01/34            Price: £11
ISBN: 1 84057 020 2

Produces an operational check list of procedures a supervisor should follow. Describes the background to overbanding treatments and lists typical problems encountered. Gives details of the equipment used, the preparation and the laying methods.

Deep Excavations: Compliance with the HAUC Specification

Ref: 97/WM/01/32            Price: £12
ISBN: 1 84057 018 0

Gives details on the practice of deep excavations, including the permanent surfacing, at five sites. Reports on their compliance with HAUC specifications. Examines the relationship between compliance and actual performance.

Overbanding Materials for Trench Reinstatements: Results after 30 months

Ref: 97/WM/01/33            Price: £12
ISBN: 1 84057 019 9

Analyses the results of thirty months of monitoring at two sites using overbanding, a treatment for sealing joints around trench reinstatements and for sealing cracks. Monitoring includes the measurement of skid resistance value, texture permeability and the profile together with visual assessments. Discusses performance against HAUC specification.

Sewer Engineering

Test Protocol to Determine the Flushability of Disposable Products, Review of the Manufacturers 3rd Edition Guidance Document

Ref: 14/WM/07/17            Price: £10
ISBN: 1 84057 706 1

in 2012, the report Test Protocol to Determine the Flushability of Disposable Products, 12/WM/07/16, was published by UKWIR. This report is supplementary to the 2012 report and is a review of the manufacturers 3rd edition guidance document which is not available at the time of publication of this UKWIR report.

The review document gives the Water Industry a far clearer understanding of the similarity (or not) between the tests and pass/fail criteria specified in the 3rd Edition Manufacturers Guidance and Water UK/UKWIR Flushability Protocol. In particular any risks brought about by the 3rd Edition Manufacturers Guidance becoming an accepted standard are brought to the attention of the Water Industry.

The review provides information that would be necessary for the Water Industry to further engage with various stakeholders, particularly INDA/EDANA, regarding their latest guidance document.

Test Protocol to Determine the Flushability of Disposable Products

Ref: 12/WM/07/16            Price: £14
ISBN: 1 84057 636 7

The flushing of disposable products has increased significantly during the last two decades. Unfortunately, many of the most commonly available products are unsuitable for disposal to sewer and are suspected of being the cause or component part of many sewer blockages, pump clogs and an increase in the volume of screenings removed at WwTW inlets.
The main objective of this project was to produce a 'Protocol to Assess the Flushability of Disposable Products' (the 'Flushability Protocol'). A series of practical and understandable tests is specified, which products should be able to satisfy before being regarded as suitable for disposal to sewer. This document is largely based on an earlier water industry protocol and guidance developed by manufacturers of disposable products.
The project, through working with product manufacturers, has enabled the water industry to be in a position to begin influencing the manufacturers' product research, customer communications and product labelling.
In 2014, a supplementary report, 14/WM/07/17, was published by UKWIR. This is a review of the manufacturers' 3rd edition guidance document. It provides information that would be necessary for the Water Industry to further engage with various stakeholders, particularly INDA/EDANA, regarding their latest guidance document. The report is entitled 'Test Protocol to Determine the Flushability of Disposable Products, Review of the Manufacturers' 3rd Edition Guidance Document' and is available for £25.

Sewerage