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Deltares, spring 2020 6 To close the gap between strategic and investment planning, Deltares developed the Financing Framework for Water Security. It guides actors in the planning process through the various stages of the Theory of Change towards a win-win situation for the economy and the environment. The result is a phased investment portfolio in which the most promising clusters of measures are developed into deals that are attractive for public and/or private investors. The Water as Leverage for Resilient Cities Initiative enabled us to develop a proof of concept for the city of Semarang, Indonesia. We demonstrated to multilateral development banks and climate funds the transformative potential of this new approach, which is centred around the water cycle dynamics and the scale of the river basin. With the introduction of this 'cascading' approach, we have developed five urban solutions: Spongy Mountain Terrace, Micro-Interventions, Rechanneling the City, Feeding the Industry and Recharging the Aquifer. They all lead to increases in the storage and utilisation of surface water which are needed to safeguard city livelihoods. For more information: monica.altamirano@deltares.nl Cascading Semarang: steps to inclusive growth Underwater dunes in big rivers reveal secrets Underwater dunes and sand ripples make up an invisible but dynamic landscape. An article was published in January 2020 in Nature Geoscience (Thaiënne van Dijk of Deltares was one of the co-authors) describing these structures in five big rivers worldwide and in the Waal in the Netherlands. The analysis is based on multi-beam field measurements of, among other rivers, the Mekong, Amazon and Mississippi by thirteen inter­ national research institutes. The beds typically have low- angle slopes, with the steepest slopes often being at the base of the downstream slope. It also emerged that these underwater dunes are often lower than previously observed in relation to water depth. This provides new insights into the functioning of complete river systems, and in particular currents and sediment transport. River managers will benefit: an exact picture of bed morphology and dynamics (and therefore water depths) is crucial for the management of a primary shipping route such as the Dutch Waal. More accurate input about bed roughness in river systemmodels provides more accurate results.