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Water Mains & Services & Leakage 

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

Reference: 18/WM/08/67
ISBN: 1 84057 863 7
Published Date: 23/11/2018

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.

Price: £150  

Fast logging for improved estimation of household night use

Reference: 17/WM/08/66
ISBN: 1 84057 848 3
Published Date: 28/03/2018

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.

Price: £200  

Measuring the performance of leak detection technicians

Reference: 15/WM/08/57
ISBN: 1 84057 794 0
Published Date: 23/12/2015

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.

Price: £350  

Assessing the Structural Condition of PVC Pressure Mains

Reference: 15/WM/04/11
ISBN: 1 84057 786 X
Published Date: 26/08/2015

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.

Price: £350