Royal HaskoningDHV Inc.

In recent years, municipalities have been recognised for their crucial role in protecting cities from climate change impacts by adopting mitigative and adaptive strategies to enhance climate resilience. However, anchoring these strategies demands multiple interventions, which are often hindered by the current siloed organization of departments and disciplines. An integrated infrastructure design approach (IIDA) can co-create a process that converges sectors, disciplines, and actors’ interests to tackle this challenge. To this end, this research explores how municipalities can effectively implement IIDA to enhance climate-resilient infrastructures. The city of Rotterdam served as a case study involving a thematic analysis of 21 interviews with internal actors of the municipality. This study identified 19 key factors influencing a municipality’s effectiveness in using an integrated design approach to enhance climate resilience. These influential factors belong to six different dimensions: Human Capacity, Organisational Culture, Governance, Communication, Project Development Process and Finance. The findings suggest that it is essential that actors within municipalities have soft skills such as proactivity and open-mindedness for collaboration. Furthermore, it is necessary to foster an innovative and collaborative culture to enable the development of pilot projects. This, in turn, helps update standards and scale up implementation by aligning integration at the three management levels: strategic, program, and project. Based on the findings, we recommend establishing a multi-dimensional baseline, setting up a communication strategy and tools, build human and institutional capacity through pilots and living labs. This can help municipalities implement an integrated infrastructure design in their organisation, offering a promising future in designing climate-resilient infrastructures.

This study evaluates the impact of varying bedrock depths on local site amplification factors and their consequent influence on the vulnerability of buildings under seismic actions. An index-based methodology is implemented to analyze the seismic vulnerability of old masonry buildings in the historic center of Galata, İstanbul. As part of a site-specific analysis, soil models are developed to replicate a dipping bedrock at six different depths varying between 5 and 30 m beneath the ground surface. Consequently, potential damage scenarios are generated employing a seismic attenuation relation and damage distributions are compared for the cases with/without amplification effects. The findings point out that, the structural response undergoes the greatest amplification at a bedrock depth of 20 m, exceeding 1.6 and attaining its maximum value of 2.89 at the structural period of 0.22 s. The maximum shift in damage grades occurs for buildings with natural periods between 0.16 and 0.20 s on 15 m bedrock depth, whereas, for longer periods, the greatest increase occurs at 20 m bedrock depth compared to the scenarios without site amplification. As a result, this study emphasizes the significance of site-specific conditions that might amplify structural response and consequently, increase the seismic damage level in assessing the vulnerability of built heritage. By integrating geo-hazard-based evaluation into the large-scale seismic assessments, this study offers a framework for more accurate damage forecasting and highlights the need to include local site amplification effects in seismic risk mitigation plans, enhancing strategies for preserving built heritage.

The challenges of providing sustainable drinking water are growing due to resource mismanagement, contamination threats and rising demand, which are further intensified by climate change. This further underscores the need for building-in resilience in existing extraction points to gain flexibility against uncertain and unforeseen developments. Although invisible, groundwater is a key drinking water source globally, including in the Netherlands, where over 60% of drinking water comes from it. The Dutch regulations, limited space and competition for water require adaptive strategies that enhance sustainability in water provision. Here, we identified and categorised various groundwater and surface water extraction archetypes in the Netherlands based on land use, extraction depth and local geology, assessing their susceptibility to contamination and operational challenges. Then, we evaluated four solution concepts to enhance sustainability in drinking water supply: the Water Battery (large-scale managed aquifer recharge), Fresh/Salt extraction (mitigated coastal salinisation), Switching between extractions (balancing demands in space) and Resource City (promoting circularity in urban water supply). Practical examples are already in place in the Netherlands as the Epe Water Battery shows successful infiltration and storage of groundwater to meet local demands and avoid undesirable low groundwater levels. We also explore the legal and operational challenges, emphasising stakeholder collaboration, proactive policies and the need for strategic investments in water quality improvement for a resilient, sustainable water supply in the face of climate change.

Internal phosphorus (P) loading is a main cause for persistent eutrophication of shallow freshwater systems and can delay restoration for decades. Iron (Fe) amendment is often used to enhance P binding in the sediment and reduce benthic P fluxes. However, sufficient dosing using Fe salts is challenging due to acidification. Fe-rich water treatment residuals (Fe-WTR) are an attractive alternative, but their behavior in aquatic sediments is poorly studied. In this field study, a ditch in a peat polder was treated with 2.5 kg Fe/m2 using Fe-WTR. Sediment porewater and solid phase analyses, including sequential Fe extraction, showed that the added Fe-WTR significantly increased the reactive Fe reservoir of the surface sediment. Sediment incubation experiments and surface water monitoring for one year indicated an efficient reduction of internal P loading. Redox cycling was found to redistribute the added Fe both laterally across the ditch and vertically towards the sediment surface. Reactive Fe phases were thus continuously replenished in the surface sediment and available for P retention via co-precipitation and adsorption, potentially increasing the longevity of the treatment. Loss of the added Fe to sulfidation was limited due to the large excess of available Fe. However, the initial P-content of the Fe-WTR also increased the sediment P reservoir by 10