The thesis deals with residential water demand management measures and to what extent such measures can provide benefits for Hamburg and increase the circularity of Hamburg’s water system. The city of Hamburg and in particular Hamburg's water sector present the case for this thesis. Climate change and a growing water demand, due to population growth and a slight increase in the per capita water consumption, pose challenges to Hamburg’s water sector, requiring reactions. Against this background, water demand management measures for households are considered throughout the thesis.
Following a case study research design, reviewing literature, and conducting semi-structured interviews serve as the research methods. Complemental to this, the concept of circular water economy and transition theory constitute the theoretical background for this thesis.
The specific extent of water demand management measures related to circularity and provision of benefits could not be determined. However, the thesis outlines the variety of benefits such measures may bring to Hamburg. These include climate mitigation, climate resilience, contributing to a secure water supply, and potentially offsetting the need to build new infrastructure to meet growing water demand. Furthermore, such measures may close the identified gap of measures, that aim to avoid and reduce water consumption in the Hamburg water sector and thereby, represent important means to increase its circularity.
Limiting the potential and the value of residential water demand measures for Hamburg is an identified path dependence between the pipe infrastructure and a specific needed amount of water consumption. Moreover, a dominating mindset in the water utility has been identified that focuses on supply-oriented solutions and neglects the multitude of benefits of reducing water consumption. Similarly, the concept of circular water economy is mainly perceived with regard to the recovery of materials and recycling of water. Therefore, to promote residential water demand management measures, this thesis argues for a mindset change that acknowledges the value of such measures for circularity and considers the full benefits they may provide.