As a part of the Design Study, ReDesigning Deltas organized four masterclasses, to give participants specialist knowledge input for their challenge. Topics included: the Dutch delta, international deltas, delta governance and delta economy. In the Dutch Delta, Deltares-specialists presented the state of the art regarding adaptation pathways, scalability, transport-corridor(s) and climate proof infrastructure, draught, subsidence, flood risk management, but also on the regional challenges of Limburg, Southwestern Delta, mouth of the Rhine-Meuse rivers and Limburg. The Dutch Delta Masterclass informed the societal challenges, that are the point of departure for sustainable spatial transformation envisioned by the design-teams in the Design Study. The societal challenges are organized in environmental (climate and biodiversity) and socio-economic drivers (housing, energy transition and new economy), that currently manifest as crises. Thus, the masterclass supported the teams with data (in particular on the climate crisis), that sketch the scope of the study in which response and vision to global warming is pursued, the driver that causes changes in the hydrological cycle, such as:

- several meters of sea level rise (3 meters above current level); as high impact, low likelihood scenario

- time horizon 100-120 years; because of the long-term impact of decisions/long term societal effect; considering years in between (-2070-2120)

- other climate extremes, precipitation / pluvial-fluvial flooding: extreme rainfall, high and low river discharge, temperature, drought; and impacts (considering the ‘Waterbom,’ and an extreme event every year in the Netherlands)

The four ‘Deltares strategies’ are presented as options on how the Netherlands can transform, but combinations of these strategies or new insights can also be a used.

To inspire the teams, the second masterclass international deltas was led by two prominent professionals from very different deltas. Dr. Atiq Rahman​, Executive Director Bangladesh Centre for Advanced Studies (BCAS), presented the Bangladesh delta, which the river remains dynamic, to bring fertility to the system. Dr. Sam Brody​, Professor of urban planning at Texas A&M (USA) presented a framework for design strategies with 4 flavors: avoidance, resistance, accommodation, and communication. The first strategy (avoidance) is about retreating and relocating people from flood zones; resistance (second) is about holding the water in place. Third, ‘accommodation’ through retention and detention reduces flood consequences with the additional benefit of living with the water. The fourth and final, ‘communication’ is about telling the story of risk, making it part of the daily life of people, officials, scientists, and decision makers.

In the masterclass delta governance, the speakers Jos van Alphen and Pieter Bloemen of the Delta Program explained how the Dutch Deltaprogramme aims to protect the Netherlands from high water and flooding, to ensure a sufficient supply of fresh water, and to contribute to rendering the Netherlands climate-proof and water-resilient. They provided insights in Adaptive Delta Management and on the research-program Increased Sea Level Rise. Geert Teisman, professor in Complex Decision Making and Process Management at the Department of Public Administration of Erasmus Universiteit, showed the potential and challenges around governance in the Dutch Delta. Teisman invited Guus van der Hoef of Zuid-Hollands Kustinitiatief, to present this initiative, and to highlight the contemporary challenges. Fabienne Bosschieter from the municipality Zuidplas talked about the integrated area development challenge in the Zuidplaspolder (Integrale Gebiedsopgave Middengebied Zuidplaspolder).

The delta economy masterclass was led by urban economist and professor at Erasmus University Rotterdam Frank van Oort. Van Oort explained the costs and benefits of urban deltas (such as agglomeration advantages), direct and indirect effects of flooding, value chains as part of interregional economic relations and urban resilience, the notion of broadly defined welfare, and studies that identify the value of density, nature, accessibility, spatial quality and water. Particularly inspiring for the case-studies was a diagram that attempts to weigh different elements of broad welfare in different flood protection alternatives such as retreat and protect.