Intertwining uncertainty analysis and decision-making about drinking water infrastructure

Intertwining uncertainty analysis and decision-making about drinking water infrastructure

Meijer, H.M.

Thissen, W.A.H. (promotor)

Technology, Policy and Management

2007-10-29

Infrastructures, generally designed to have a long service life, are particularly vulnerable to long term changes that can influence their functioning. Therefore it is important that uncertainties are taken into account as much as possible from the beginning of the planning process of infrastructures. This thesis focuses on drinking water infrastructure. This type of infrastructure is characterized by a long life expectancy. Changes in the supply of materials (for instance source water, energy, space for building underground networks), technology, and demand for the end product can be expected, but are difficult to predict. These changes can lead to high cost for society when they lead to system failure or obsoleteness of the existing infrastructure. The main objective of the research was to answer the following question: Can the identification and handling of uncertainties in the Dutch drinking water infrastructure planning process be improved? And if so, how? To answer this question, first a literature study was performed, which was used as a basis to develop both a descriptive and a normative framework for the analysis of case studies. These frameworks then were used to analyze four case studies ex post. Finally, a workshop was used to discuss the overall results with representatives from the drinking water field. The descriptive framework is based on an approach in which a system is described as well as the influences on that system. These influences can come from external variables that cannot be influenced by a decision-maker and from tactics that a decision-maker can use. The effect of both on the system can be observed in changes in the outcomes of interest that a decision-maker has. The normative framework was developed to evaluate the success of drinking water companies in their efforts to deal with uncertainty. It is based on a causal chain of actions in a planning process that should lead to successfully dealing with uncertainty. It was chosen to use indicators of success within the causal chain as proxies for the overall success of a drinking water company in dealing with uncertainty. For each step in the causal chain a indicator of successfully performing this step was identified. The idea was that if each step is performed well, overall success in dealing with uncertainty will follow. Four cases were studied in retrospect, of which three were recent and one was further in the past. The most important conclusion of the cases was that drinking water companies are very aware of uncertainties and a lot of action is taken to handle them. However, some suggestions can be made to improve the analysis and handling of uncertainties. Firstly, the case studies showed that not all potential critical external influences received the same amount of attention. Political, social en technological considerations were found the most crucial in the cases that were studied. Political and social influences were also found to be most difficult to handle. Secondly, some external influences were recognized in the cases, but were not included in the analysis, because not enough was known about them. For instance in the case of the success of drinking water saving actions this external variable showed to be critical. If this influence would have been considered in more detail maybe other decisions would have been made. Thirdly, the cases showed that assumptions were made more explicit after they had failed. If they had been made more explicit beforehand maybe decisions to change policy could have been made sooner.

uncertainty analysis
drinking water infrastructure
planning

http://resolver.tudelft.nl/uuid:62f4868a-7a2e-4e28-aa87-a036915bf55a

978-90-9022350-6

Institutional Repository

doctoral thesis

(c) 2007 M.H. Meijer