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The natural environment in port development: a ‘green handbrake’ or an equal partner?
Rapid urbanization of the coast, growing global trade, stakeholder emancipation and ongoing depletion of natural resources implies that ports can no longer operate and develop without acknowledging and incorporating societal and environmental considerations. Drawing primarily on first-hand experiences in South African ports, supplemented with learning taken from international literature, this paper proposes a conceptual change in the position of the natural environment in port development from that of a ‘green handbrake’ to ‘equal partner’. The argument for this conceptual change is developed in three stages. First, we merge two concepts emerging from the literature, namely natural capital (or natural infrastructure) and infrastructure systems, to embed the natural environment as an integral component or ‘equal partner’ in port development. We then identify practical avenues through which the profile (or value) of the natural environment can be enhanced in port development, drawing on concepts such as Building with Nature (BwN) and multi-use of natural capital. Finally, we build a framework for Integrated Port Management (IPM) by conceptually positioning and aligning environmental processes within the traditional port development cycle, as well as identifying the need for coordination across and continuity between individual environmental assessment processes. In essence, bridging the disconnect between natural environmental issues and port development requires early consideration of the natural environment in port development, and an acknowledgement of multi-use benefits from natural capital. Further, in the operations and maintenance phases, environmental management systems in ports should not only focus on environmental performance, but also embrace multi-use valuation of the natural environment (ecosystem services) to give purpose to the need for environmental protection. However, crucial to effective implementation of an Integrated Port Management (IPM) framework will be its integration in organisational processes, supported by collaborative institutional structures. Only then will the environment take its place as equal partner in port development.
The potential of nature-based flood defences to leverage public investment in coastal adaptation : cases from the Netherlands, Indonesia and Georgia
Nature-based flood defences (NBFD) are receiving considerable attention in the coastal adaptation field. Advocates of NBFD point to their cost-effectiveness, flexibility and the range of co-benefits they produce beside flood risk reduction. However, NBFD are not yet common practice. One reason for this may be found in financial barriers. To date, there has been little attention for financial aspects of NBFD, as the literature has focused on design, effectiveness and socio-economic impact of such projects. We address this gap by analysing the financial attractiveness of real-world NBFD from the perspective of the public actor. We address the following research questions: through which mechanisms can public investments in NBFD projects be leveraged? ; and what are the enabling conditions for these mechanisms? We find two types of revenue generating mechanisms: value capture, in which the public actor generates revenues from private beneficiaries through taxes; and co-investment, in which the project attracts in-kind or cash contributions from other actors. We illustrate the potential of these leveraging mechanisms in four case studies and find that NBFD can generate significant tax revenues in locations with high demand for certain co-benefits, whereas project size, type, timing and beneficiaries of co-benefits determine the potential for co-investment.
Environmental compensation for port extension : the case of Rotterdam harbor and nature compensation, policy and practice
The port of Rotterdam recently built a large extension, Maasvlakte 2. It was built in an area with valuable coastal ecosystems belonging to the EU Natura 2000 network of European conservation areas. The construction and use of Maasvlakte 2 causes considerable damage to existing Natura 2000 sites. According to EU regulations this damage should be compensated by creating new nature. In the case of Rotterdam, the compensation was twofold: a marine and a terrestrial part. The paper describes the design and the actual lay-out of the compensation works. It also reports on the monitoring that is ongoing to assess the damage to existing nature and the quality of the new (compensated) nature.
The Giving Delta : a "systems approach" to a consolidated and sustainable Lower Mississippi River Delta
While generating prosperity for many generations, more than a century of levees-only policy for the training of the Mississippi River to limit riverine flood risk, and river management designed to safeguard navigation, has resulted in massive land loss that threatens communities along the Gulf coast including New Orleans. It has long been recognised that this approach would need to be adjusted, since the consequences of the current strategy, for this and future generations, are increasingly apparent, with the negative impacts increasingly outweighing the positives. To this end, the "Changing Course Design Competition" was established reflecting a growing understanding of the scale and complexity of challenges we will face with increased sea level rise and climate change, both in Deltas and more generally across the globe. This paper outlines the Giving Delta response to the Changing Course Design Challenge, a framework developed by a partnership between US and European private sector, Academic Institutions and Centers of Excellence. Our “design-with nature” approach results in a radical retooling of the management of the Mississippi River and integrated investment strategy as the primary decision drivers. Instead of completely restoring the Mississippi Delta to its natural landscape, a bold, innovative “systems approach” was established in linking the specific needs of the region’s ecosystem, economy and community.
Woods versus waves: wave attenuation through non-uniform forests under extreme condition
Worldwide, communities are facing increasing flood risk, due to more frequent and intense hazards and rising exposure through more people living along coastlines and in flood plains. Nature-based Solutions (NbS), such as mangroves, and riparian forests, offer huge potential for adaptation and risk reduction. The capacity of trees and forests to attenuate waves and mitigate storm damages receives massive attention, especially after extreme storm events. However, application of forests in flood mitigation strategies remains limited to date, due to lack of real-scale measurements on the performance under extreme conditions. Experiments executed in a large-scale flume with a willow forest to dissipate waves show that trees are hardly damaged and strongly reduce wave and run-up heights, even when maximum wave heights are up to 2.5 meters. It was observed for the first time that the surface area of the tree canopy is most relevant for wave attenuation, but that the very flexible leaves hardly add to effectiveness. Overall, the study shows that forests can play a significant role in reducing wave heights and run-up under extreme conditions. Currently, this potential is hardly used but may result in considerable cost savings in levee designs.
Shifting the discharge mind-set from harmful to habitat : exploring inventive designs and benefits of underwater discharge structures
With the aim to protect the marine environment, regulations have been set to regulate the brine discharges, and defining environmental criteria in the area close to the outfall. It was however noted, that such criteria are often adopted from generic benchmarks and sometimes from unadoptable locations. Robust and in situ research on the effects of the brine effluent on the marine environment is also lacking. Recent surveys however suggest that the ecological impact of brine outfalls can be very limited or even result in an improvement of biodiversity and marine abundance on the outfall structure. Such observations suggest that some environmental criteria may be archaic, which may result in needlessly expensive outfall designs.
Tubifex worms improve densification rates and the strengthening of soft sediments and mine tailings
Laboratory tests on oil-sand fluid fine tailings proved that Tubifex worms improve densification by up to 60%. This nature-based technology represents a potential alternative to chemical additives such as flocculants. The potential applications of Tubifex augmentation include tailings basin closure, land reclamation and flood defence projects.
Opzet monitoringsplan voor ecologische meerwaarde van het Wervenpark in Dordrecht
Het Wervenpark in Dordrecht wordt ontwikkeld volgens de principes van Bouwen met de Natuur (Building with Nature). Dit voormalige bedrijventerrein wordt ingericht als getijdenpark waar een natuurlijke dynamische intergetijdenzone wordt gerealiseerd. In dit rapport wordt beschreven hoe de effecten van een dergelijke inrichting in zoetwatergetijdengebied op de ecologie kunnen worden gemonitord en gewaardeerd. De generieke opzet van een monitorsplan wordt weergegeven. Achtereenvolgens worden de verschillende stappen besproken: beschrijving van de maatregel en verwachte effecten; monitoringsvragen; te monitoren parameters; monitorprogramma; optimalisatie monitorprogramma en kostenafweging monitorprogramma. Hierna wordt nader ingegaan op de waardering van de resultaten, en wordt specifiek behandeld hoe het begrip 'connectiviteit' beoordeeld kan worden.
Deformations and damage to buildings adjacent to deep excavations in soft soils : literature survey F531
Vegetation modelling to assess the development and performance of nature-based flood defences
The assessment of the performance and development of nature-based flood defences and natural/semi-natural systems requires efficient quantitative tools. Drawing on experience with these systems and software, we developed an open source tool for biophysical modelling based on Python, Delft Flexible Mesh and XBeach.