In times of increasing pressures on water resources, the integrated management of the resource is a central policy objective. While there exists encompassing research about the concept of integrated water resources management (IWRM), much remains to be studied regarding the integration of water-related policies. Water resources management profits when policy actors coordinate their demands and actions across policy sectors, territorial entities, and decision-making levels within a water basin. However, actors are bound by the policy framework, which organizes water resources management in defined sectors and, over time, develop into independent and specialized policy pillars. A growing number of policies increases the need to integrate those policies over time following the institutional resources regime (IRR) framework. However, an increasing number of policies also proves challenging in establishing an integrated, coherent regime compliant with IWRM. In this study, we analyze flood risk management policies and find an almost exponential increase in policies over time, while flood risks and damage have not decreased in parallel. We address this empirical puzzle with an in-depth analysis of the design of Swiss flood risk management policies over time. To this end, we survey the opinion of 146 flood experts on the importance of ten policy design indicators in three flood-prone regions in Switzerland. Flood risk management experts attribute particular importance to policy designs characterized by integration, a sufficient budget for policy implementation, and coercive instruments and sanctions. We then compare survey results to the ways in which Swiss policies have been designed in legislation across policy sectors related to flood risk management over the last 169 years. We find that policy designs follow a national policy style. Placing these results in local contexts, we explain why the design of policies represents both a challenge and opportunity for policy-makers involved in flood risk management.