ABSTRACT

The water and sewerage industry in England and Wales had undergone several reforms since its privatization. To evaluate to what extent they had impacted on the performance of water companies, an input distance function and its derived cost share equations was estimated. This allowed measuring technical efficiency, economies of scale and cost complementarities between water and sewerage services over the period 1991–2016. The results indicate that an average water and sewerage company (WaSC) reported a technical efficiency score of 0.731 which means that its inputs could be reduced by 26.9% over time. It is also shown that an average WaSC operated under decreasing economies of scale. Cost complementarities between water and sewerage connected properties were found. This implies that WaSCs could benefit from remaining integrated, i.e. providing both water and sewerage services.

摘要

英格兰和威尔士的供水和污水处理行业自私有化以来经历了多次改革。为了评估它们对供水公司业绩的影响程度，我们估计了输入距离函数及其派生的成本份额方程。这允许衡量 1991 年至 2016 年期间供水和污水处理服务之间的技术效率、规模经济和成本互补性。结果表明，平均供水和污水处理公司 (WaSC) 报告的技术效率得分为 0.731，这意味着随着时间的推移，其投入可以减少 26.9%。还表明平均 WaSC 在规模经济递减的情况下运行。发现水和污水连接属性之间的成本互补性。这意味着 WaSC 可以从保持整合中受益，即