Consistency of Reporting Performance Measures

Reference: 17/RG/04/5
ISBN: 1 84057 834 3
Published Date: 10/07/2017

Water companies have been working together, coordinated by Water UK and supported by Ofwat, to develop more consistent reporting methodologies for the measurement of leakage, supply interruptions and sewer flooding.

As part of this work Water UK requested UKWIR commission an independent review and challenge of the initial proposals, to provide assurance and to develop more detailed guidance.

UKWIR commissioned Atkins to carry out this review, working with company practitioner experts and a steering group including representation from companies, Ofwat,  the Environment Agency, the Consumer Council for Water and Water UK.

Ofwat has confirmed that the output of this project will not impact on PR14 PCs and ODIs. It is intended to form the basis of public reporting from 2020/21 and to inform the development of PR19 Business Plans, and the detailed reporting guidance documents are below.

This report can be downloaded free of charge by clicking here.

Price: £15  

Modelling Sludge Opex Efficiency

Reference: 11/RG/04/4
ISBN: 1 84057 590 5
Published Date: 23/05/2011

The main objectives of this project were to: understand the data and methodological issues that appear to have restricted previous attempts to model sludge operating costs, and; develop a robust approach to explain the variation in sludge operating costs across companies.
The first stage of the project provided recommendations to mitigate the issues identified with the data and approaches used in previous analysis. In the second stage, these recommendations were explored and econometric models for sludge expenditure were developed. These models demonstrate emperically that sludge volumes, landbank availability and population density are drivers of sludge expenditure. Data limitations have meant that it has not been possible to tackle all the issues identified in the project. However, the analysis does go some way to developing a robust econometric model for sludge costs that could be used as an alternative to the current Ofwat unit cost model.

Price: £13  

Application of Time Series Analysis to Relative Efficiency Assessment

Reference: 08/RG/04/3
ISBN: 1 84057 487 9
Published Date: 09/04/2008

Ofwat carries out relative efficiency analysis as part of its price control reviews. To date, Ofwat's analysis has focused on cross-sectional methods. A previous report for UKWIR, Review of the Approach to Efficiency Assessment in the Regulation of the UK Water Industry (07/RG/04/2), recommended the consideration of econometric modelling of time series panel data.

This report presents a series of time series panel data models for water service and sewerage service operating expenditure. It provides guidance on the specification and interpretation of time series models. It explains how these models could contribute to relative efficiency analysis for price control reviews.

The project also included the development of time series datasets and a software tool to specify and estimate time series models.

Price: £37