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ABSTRACTMore than a decade has passed since the International Panel on Climatic Change began to study (in depth) the possibility that the global climate was changing. Increasing attention is also being paid to the impact of such changes on society in general, and on the planning and management of water resources. Not least among the water resources planning problems is the estimation of the changes which might occur in public water‐supply demands. Such changes are notoriously difficult to evaluate, particularly in the UK where most domestic premises remain un‐metered. Elsewhere, econometric models involving climatic parameters as independent variables have had some success, but a recent application of this approach in the UK was unable to identify particular parameters which had a consistent influence over the summer period. This lack of success might be partly caused by the public reaction to summer conditions being a complex function of several parameters, such as duration of sunshine, temperature and rainfall. This complexity has already been recognised by climatologists, who have devised forms of summer indices involving weighted combinations of climatic variables to determine how 'good' or 'bad' a particular period might be perceived by the general public. The use of one such summer index to explain the variations in an index of demand for public water supply in the London supply area has shown that simple and consistent relationships can be derived. Application of these relationships to scenarios of changes in temperature, sunshine duration and rainfall totals for the year 2050 shows an increase of 0.6‐ 2.9 index points in water‐supply demand over the 1950‐1990 period average.

AbstractThe estimation of water demand is fundamental to effective water resource management. Water supply is measured at district level but true demand is not, and therefore studies of water‐pricing relations are limited and mass‐balance based assessment of leakage, illegal use, meter inaccuracies etc., are compromised. This paper describes the value and limitations of existing geodemographic methods, and an alternative technique widely used in other fields, microsimulation, is proposed. It is shown that geographic stability in demand relations is not found in all consumer commodities and cannot be assumed for water. Sampled data for Leeds, West Yorkshire, are used to construct a microsimulation model, and the results of that model are applied to the city of Leeds at ward level. Applicability is also demonstrated at enumeration district level.

PurposeThe water sector is set to continue to face severe challenges in meeting the financial requirements for maintaining, extending and upgrading new and ageing water systems in the face of growing water scarcity, stricter regulatory requirements and competition for capital. The gap between the required financing and the projected financing is said to be growing but there are no good estimates available. The purpose of this paper is to present a recent analysis of the investment requirements of the water sector in OECD countries, Brazil, Russia, India and China up to 2030, taking into account the likely impact of socio‐economic trends, internal politics, environmental challenges and technological change.Design/methodology/approachIn order to estimate the required financing, present expenditures as a percentage of GDP were analysed. Estimates of projected annual GDP growth coupled with an evaluation of the impact of country specific socio‐economic, political, environmental and technological trends were used to derive projections for future investment needs.FindingsThe estimated level of infrastructure investment requirements to 2030 as determined by this study is considerably higher than had been expected and higher than for the energy, telecommunications and transport infrastructure sectors.Practical implicationsThe findings have enormous implications in terms of the ability of service providers for their business models and in raising the necessary finances.Originality/valueThis is one of a very few studies to report on the potential scale of the overall future investment requirements of the water sector that has been undertaken. Previous works have focused mainly on sub‐sectoral goals such as meeting the Millennium Development Goals and so have under‐reported the scale of the financing problem.

The Angolan State&rsquo ; s post-war center-piece reconstruction program, to provide the human right to &lsquo ; Water to All&rsquo ; remains incomplete. The majority of Angola&rsquo ; s peri-urban communities still use the informal market to fill the gap. Water selling is the largest sub-sector of Luanda&rsquo ; s extensive informal economy, involving extractors, transporters and retailers. Negotiating for water at the local household level involves significant trading in social capital. Communities in Angola&rsquo ; s musseques have built on neighborhood solidarity to manage the supply of water themselves. The article is drawn from the authors&rsquo ; experience in practice to examine the complexity of Angola&rsquo ; s informal water economy and local-level innovative responses. The Government has drawn on these lessons and adopted the community management model MoGeCA (the Portuguese language acronym for Model of Community Water Management)to help address the shortfall. The article is written from a practitioner's point of view, based on more than a decade of experimentation in practice and support from USAID and UNICEF in taking community management to the national scale.

This paper examines water consumption in group‐metered households. A utility‐maximising model is developed in which the marginal price schedule is approximated by a polynomial function of water consumption. The model is modified to allow for an incentive for group‐metered households to consume more water than if they were separately metered. This occurs if households do not expect their own increase in water consumption to be matched by other households sharing the meter, so that part of the marginal cost of water is shifted to other households. Estimates using Western Australian data are, however, unable to detect any significant effect of this kind, perhaps because the price response itself is small.