Operational decision-making for sewer asset management has hardly been empirically analysed, hampering the current challenge for cost-effectiveness in the urban drainage sector. This paper analyses how decisions for sewer replacement are actually made and to what extent complexity of the decision-making environment is addressed. Decision argumentation of 150 sewer replacement projects in the Netherlands was obtained by interviews. The decision process was analysed by the rational and streams model. The decision argumentation is a relatively wide variety of information sources, of which the majority is case-specific. Yet, decision-making does not rely purely on data analysis; it also includes negotiations between involved infrastructure managers. Then, replacement planning of a sewer asset manager depends on other public works. Consequently, individual cost-effectiveness as an evaluation criterion should be expanded to include group utility.

Decision-making for sewer asset management is inherently complicated, because of limited data and interaction with multiple actors, making it neither transparent nor reproducible, mostly based on intuition. It is unclear which and how information sources and intuition are used for sewer pipe replacement decisions. Therefore, this study assesses the use of information and intuition in decision-making for replacement decisions. Next to that, the success of the intuitive decisions is addressed. Interviews were conducted at seven municipalities in the Netherlands, combined with analyses of their strategic municipal sewerage plans. Content analysis identified twenty-one information sources used in intuitive risk analyses considering the following five aspects: pipe collapse, insufficient hydraulic performance, nuisance to citizens and related reputation of the organization, traffic disruption, costs for excavation and costs for surface level reconstruction. Given the complex context of sewer asset management and limited data, intuitive decision-making is favoured, but is however not skilled.

Operational decision-making processes for networked infrastructure management often occur as a multiactor planning problem, implying these are based on negotiations between different stakeholders in addition to available system quality information. As such, does more accurate data about actual structural condition lead to other or better decision-making? A serious game is introduced, Maintenance in Motion, aiming at investigating the influence of information quality on rehabilitation decisions, for single-and multi-actor decision-making. Players manage drinking water, gas, sewer and street infrastructures. They are to balance their individual goal, cost-effectiveness, with their team utility, increasing overall infrastructure quality to minimise failure while minimising overall public costs. The game design, calibration and solution space are presented. this is an Open access article distributed under the terms of the creative commons attribution-noncommercial-noderivatives License (http://creativecommons.org/ licenses/by-nc-nd/4.0/), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way.

Decision-making for sewer asset management is partially based on intuition and often lacks explicit argumentation, hampering decision transparency and reproducibility. This is not to be preferred in light of public accountability and cost-effectiveness. It is unknown to what extent each decision criterion is appreciated by decision-makers. Further insight into this relative importance improves understanding of decision-making of sewer system managers. As such, a digital questionnaire (response ratio 43%), containing pairwise comparisons between 10 relevant information sources, was sent to all 407 municipalities in the Netherlands to analyse the relative importance and assess whether a shared frame of reasoning is present. Thurstone's law of comparative judgment was used for analysis, combined with several consistency tests. Results show that camera inspections were valued highest, while pipe age was considered least important. The respondents were pretty consistent per individual and also showed consistency as a group. This indicated a common framework of reasoning among the group. The feedback of the group showed, however, the respondents found it difficult to make general comparisons without having a context. This indicates decision-making in practice is more likely to be steered by other mechanisms than purely combining information sources.

The influence of information quality on decision-making for networked infrastructure management Wouter van Riel a , Jeroen Langeveld a,b , Paulien Herder c and François Clemens a,d a faculty of civil engineering and geosciences, Section Sanitary engineering, delft university of technology, delft, the netherlands; b Partners4urbanWater, nijmegen, the netherlands; c faculty of technology, Section energy and Industry, Policy and Management, delft university of technology, delft, the netherlands; d deltares, delft, the netherlands ABSTRACT Operational decision processes for networked infrastructure management often occur as a multi-actor planning problem, implying these are partly based on negotiations between different stakeholders. The starting point for negation for each stakeholder is the available information about the structural condition of his infrastructure. In this respect, this leads to the question: 'does more accurate data about actual structural condition lead to other or better decision-making?' A serious game is introduced, 'Maintenance in Motion' , aiming at investigating the influence of information quality about structural condition on replacement decisions, for single and multi-actor decision-making. Players are challenged to balance their individual goal, cost-effectiveness, with their team utility, increasing overall infrastructure quality to minimise failure while minimising overall public costs. Results show that if players are presented with perfect instead of imperfect information, in a single player environment, they played more cost-effectively. The availability of perfect instead of imperfect information about object state hardly changes game outcome in terms of team utility. It means collaborative choices for team utility are primarily based on negotiations that lead to compromises, instead of analytical reasoning as a group. This indicates that efforts in improving decisionmaking by improving information quality are only partly effective.