Access to safe drinking water is one of the most important preconditions for a society. A lack of clean water constitutes a serious threat in many respects. Even where there is no direct scarcity of water it is necessary to prevent and manage risks such as the consequences of climate change or bacteria in the water sources, as well as inferior infra-structure or poor maintenance. Most risks are transboundary, meaning that they are not limited to a jurisdictional or geographical area. In order to manage risks, it is therefore necessary that the decision makers (often local governments) are willing to collaborate and support each other rather than acting out of self-interest. But local politicians must have support from the citizens to find legitimacy for such collective action. In this study, we investigate if and to what extent citizens in Swedish municipalities are willing to support collective action concerning drinking water risk management. Are citizens willing to pay higher fees in order to prevent risks that threatens drinking water safety? Are citizens willing to pay higher fees even if the risks emanate from another municipality than their own? We use the case study of the Göta River water system in Sweden, that serves as drinking water supply for 700.000 people in several local municipalities. This water system provides a paradigmatic case of transboundary risk. We use an innovative method consisting of survey experiments in order to frame drinking water risks in different ways. We provided all respondents with information concerning that several risks threaten drinking water. Further, we framed the issue as an upstream-downstream problem by providing the experiment group with information concerning that risks are transboundary, and that incidents upstream may affect downstream municipalities as well. The preliminary results show that respondents living downstream in the experiment group are less willing to pay higher fees to prevent risks than downstream residents in the control group. We interpret this as that citizens’ support for collective action when it comes to drinking water risk management is limited. This may have consequences for the possibilities to manage transboundary risks in an effective way.