Search results for "Sewerage"
showing 10 items of 13 documents
Financial winners and losers since the privatization of the English and Welsh water and sewerage industry: a profit decomposition approach
2020
Evaluating changes in profit, price and productivity over time can be of great importance for regulated water industries. We investigate the drivers of profit, price (capital, labour and other inputs) and productivity change (cost efficiency change, technical change and scale effect) and the recipients of productivity change (consumers, the business itself, employees and other resource suppliers) of the English and Welsh water and sewerage companies over the period of 1995–2016. The results indicate that the profit decreased over time due to the negative quantity effect, which offset the positive price effect. A further decomposition of the quantity effect illustrates the negative impact of…
American cockroach control assays in the municipal sewerage system of Valencia (Spain)
2013
ABSTRACT Several insecticides (including different active substances and formulations) were applied to sewer shafts to control Periplaneta americana (LINNAEUS, 1758) populations in Valencia (eastern Spain). Results show that the best products for cockroach control were the paints (with and without insecticide), which provided an optimal reduction of P. americana populations for up to three months (P < 0.001). Therefore, it is important to note that the reduction of cockroach populations as well as the persistence of the insecticide effect in sewers was similar in both types of paints. A product combining two pyrethroids (Tetramethrin and Alfacipermetrin) and piperonyl butoxide also gave …
Performance assessment of water companies: A metafrontier approach accounting for quality of service and group heterogeneities
2021
Abstract The assessment of water companies’ efficiency, productivity and quality of service is part of the process to set water tariffs and therefore, is relevant for regulators and customers. However, the water industry involves several heterogeneous water companies. Following a pioneering approach, this study estimates productivity change and its drivers considering the non-homogeneous nature of the water companies and incorporating quality of service variables as undesirable outputs. In doing so, the metafrontier Malmquist Luenberger productivity index was estimated for a sample of English and Welsh water and sewerage companies (WaSCs) and water only companies (WoCs) over the years 2001–…
Assessing the productivity change of water companies in England and Wales: A dynamic metafrontier approach
2017
The assessment of productivity change and its drivers across water companies and over time is a powerful tool for both regulators and companies when setting water tariffs. Water and sewerage companies (WaSCs) and water only companies (WoCs) provide different services. Hence, their productivity change cannot directly be evaluated jointly. In this paper and for the first time, we provide a pioneering approach to assess and compare the dynamics of productivity change of WaSCs and WoCs. To achieve this, both the traditional Malmquist productivity index and the metafrontier Malmquist productivity index and its components are computed to assess the productivity change for a sample of English and …
Dual Multilevel Urban Drainage Model
2005
In urban areas, when heavy rains occur, the discharge capacity of sewers is usually unable to transport the effective rainfall reaching the streets. When the runoff flow rate exceeds the capacity of the storm sewer system, the excess flow is conveyed through the street network as overland flow. A dual model is proposed for modeling the system as a double network, formed by an upper network of open channels (street gutters) and a lower network of closed conduits (sewer pipes). What is new in this model is its capacity to take into account the hydrodynamic relationship between the flows in the upper and lower networks. The model is applied to computing the response of a real monitored basin; …
The impact of privatization approaches on the productivity growth of the water industry: A case study of Chile
2015
Abstract The water industry faces the challenge of implementing privatization reforms. This process mainly adopts the following two approaches: the privatization of public water and sewerage services (WSS) and the privatization of water companies’ ownership. This paper investigates the impact of both privatization approaches on changes in productivity in the water industry. In doing so, the Luenberger productivity indicator (LPI) was computed for a sample of Chilean water and sewerage companies (WaSCs) for the period 1997–2013. Unlike the most commonly applied index (Malmquist productivity index), the LPI simultaneously takes into account output expansion and input contraction. The results …
Assessing the marginal cost of reducing greenhouse gas emissions in the English and Welsh water and sewerage industry: A parametric approach
2021
Abstract Reducing greenhouse gas (GHG) emissions involves effort from different sectors of the economy, including the water and sewerage industry. This study estimates the marginal cost of curtailing GHG emissions in the water and sewerage industry using stochastic frontier analysis techniques for a sample of ten English and Welsh water and sewerage companies over the 2010–2019 period. Results illustrated that the average marginal cost of reducing GHG emissions was 0.181 £/Kg CO2 equivalent. The marginal cost estimated notably differs across companies and over time. Findings further illustrate the impact of water companies' operating characteristics on the marginal cost of reducing carbon e…
Profit change and its drivers in the English and Welsh water industry: is output quality important?
2014
Abstract The assessment of profit change over time and its drivers is essential to analyse firms' financial performance. This paper investigates profit change and its components for the 10 English and Welsh water and sewerage water companies over the period 1991–2008 and for three regulatory sub-periods. Profit changes and their drivers are computed following two approaches, namely: without controlling for water and sewerage quality issues, and after decomposing the output effect into high quality and low quality output effect. In both cases, profit change is decomposed into various factors such as quantity and price effect, technical change, efficiency change, resource mix, product mix, an…
Drivers of productivity change: a comparison of English and Welsh water only and water and sewerage companies
2021
In regulated industries, such as the water industry, it is of great significance to estimate productivity change as it helps policy makers to evaluate the effectiveness of regulatory regime and ind...
Accounting for service quality to customers in the efficiency of water companies: evidence from England and Wales
2015
This paper investigates the role of service quality to customers in the efficiency assessment of water companies in England and Wales. To achieve this, data envelopment analysis techniques are employed to compute the technical efficiency of the water companies following two approaches: (i) traditional assessment based on quantity variables (without the inclusion of service quality variables) and (ii) alternative assessment considering quantity and service quality variables as undesirable outputs. The analysis covers 22 water and sewerage companies and water only companies providing drinking water services. The results indicate that the traditional efficiency assessment reveals a high level …