This opinion paper reflects on the current challenges facing urban drainage systems (UDS) research, along with solutions for fostering sustainable development. Over the course of a year-long project involving 92 participants aged 24-38, including PhD candidates, post-doctoral researchers, and early-career academics, we identified critical challenges and opportunities for the sustainable development of UDS. Our exploration highlights four key challenges: limited public visibility leading to resource constraints, insufficient collaboration across subfields, issues with data scarcity and data sharing, and geographical specificities. We emphasise the importance of raising public and political awareness regarding UDS's vital role in climate adaptation and urban resilience, advocating for blue-green infrastructure and open data practices. Additionally, we address systemic academic barriers that hinder innovative research. We call for a shift away from metrics that prioritise quantity over quality. We recommend establishing stable career pathways that empower early-career researchers. This paper aims to catalyse a broader community dialogue about the future of UDS research, uniting voices from various career stages. By presenting actionable recommendations, we aim to inspire fundamental changes in research conduct, evaluation, and sustainability, ensuring the field of UDS is prepared to meet pressing urban water management challenges worldwide.

Blue green infrastructure (BGI) is widely implemented as an adaptive stormwater management measure at the household level to reduce flood risk. However, more greenery also raises water demand during droughts due to higher evapotranspiration. This study examines the impact of 14 commonly used BGI types on household water balance under climate projections in the Netherlands. Several scenarios were modeled, from a ‘Grey’ setup with no BGI to a ‘Greenest’ option with an intensive green roof, facade, and orchard. Intermediate configurations were also analyzed, representing more common household configurations. On a typical 100 m2 household plot, the ‘Greenest’ option results in an extra demand of 154.3 L/day. This exceeds the current average daily indoor water use of a typical household of 129 L/day. In contrast, intermediate setups with a native plant garden or fully grassed garden and a gray roof require 8.4 and 9.9 L/day, respectively. To meet 80% of the projected additional external water demand from intensified greenery, intermediate setups need up to 2.3 m3 of rainwater tank. The ‘Greenest’ option requires 14.9 m3 of water storage to achieve the same coverage, underscoring the challenge of balancing space for water harvesting systems and intensified greenery within a limited household plot.