A systematic design approach for objectifying Building with Nature solutions

Hydraulic engineering infrastructure is supposed to keep functioning for many years and is likely to interfere with both the natural and the social environment at various scales. Due to its long life-cycle, hydraulic infrastructure is bound to face changing environmental conditions as well as changes in societal views on acceptable solutions. This implies that sustainability and adaptability are/should be important attributes of the design, the development and operation of hydraulic engineering infrastructure. Sustainability and adaptability are central to the Building with Nature (BwN) approach. Although nature-based design philosophies, such as BwN, have found broad support, a key issue that inhibits a wider mainstream implementation is the lack of a method to objectify BwN concepts. With objectifying, we mean turning the implicit into an explicit engineerable ‘object’, on the one hand, and specifying clear design ‘objectives’, on the other. This paper proposes the “Frame of Reference” approach as a method to systematically transform BwN concepts into functionally specified engineering designs. It aids the rationalisation of BwN concepts and facilitates the transfer of crucial information between project development phases, which benefits the uptake, acceptance and eventually the successful realisation of BwN solutions. It includes an iterative approach that is well suited for assessing status changes of naturally dynamic living building blocks of BwN solutions. The applicability of the approach is shown for a case that has been realised in the Netherlands. Although the example is Dutch, the method, as such, is generically applicable

Objectifying Building with Nature strategies: Towards scale-resolving policies

By definition, Building with Nature solutions utilise services provided by the natural system and/or provide new opportunities to that system. As a consequence, such solutions are sensitive to the status of, and interact with the surrounding system. A thorough understanding of the ambient natural system is therefore necessary to meet the required specifications and to realise the potential interactions with that system. In order to be adopted beyond the pilot scale, the potential impact of multiple BwN solutions on the natural and societal systems of a region need to be established. This requires a ‘reality check’ of the effectiveness of multiple, regional-scale applications in terms of social and environmental costs and benefits. Reality checking will help establish the upscaling potential of a certain BwN measure when addressing a larger-scale issue. Conversely, it might reveal to what extent specific smaller-scale measures are suitable in light of larger regional-scale issues. This paper presents a stepwise method to approach a reality check on BwN solutions, based on the Frame of Reference method described in a companion paper (de Vries et al., 2020), and illustrates its use by two example cases. The examples show that a successful pilot project is not always a guarantee of wider applicability and that a broader application may involve dilemmas concerning environment, policy and legislation

Ecological impact of land reclamation on Jiangsu coast (China):A novel ecotope assessment for Tongzhou Bay

China's continuous and rapid economic growth has led to the reclamation of large sections of the intertidal mud coast in combination with port construction, such as that of the proposed Tongzhou Bay port on the Jiangsu coast. These reclamations threaten the local ecosystem services. An ecotope distribution map was created and a hydrodynamic numerical model of Tongzhou Bay was set up to quantify the impacts of reclamation on the ecosystem. Based on the field data and model results, several abiotic features were classified into 11 ecotopes and visualized in an ecotope map of the Tongzhou Bay ecosystem. Validation with spatial distributions of two threatened shorebird species (bar-tailed godwit and great knot) showed confirmation with the mid-range and low-range littoral zones (inundated from 40% to 100% of a tidal cycle), indicating the importance of the areas with these conditions to these populations. Overlaying the ecotope map with recent and proposed land reclamation schemes revealed a loss of ecotopes, composed of the high-range (42%), mid-range (48%), and low-range (38%) littoral habitats, corresponding to a 44%–45% loss of the most important ecotopes for bar-tailed godwit and great knot (mid-range and low-range littoral zones). These results confirm the applicability of the novel ecotope assessment approach in practice

Building for nature:Preserving threatened bird habitat in port design

The fast economic development of the People's Republic of China has created an increasing demand for usable land, resulting in large-scale land reclamations along the coastal zone. One of these regions is Tongzhou Bay (Jiangsu coast), a region characterized by large intertidal mudflats and deep tidal channels with potential for the development of agri-aquaculture and the construction of a deep-sea port. However, these intertidal mudflats also provide vital ecosystem services and support many wildlife species, including several endangered migratory shorebirds within the East Asian-Australasian Flyway. With increasing realization of the importance of maintaining such ecological values, a more integrated coastal development strategy is needed. This study aims to develop a sustainable integrated design for the Tongzhou Bay port, following a "Building with Nature" approach. We use a morphodynamic model to compute habitat suitability for two shorebird species (Great KnotCalidris tenuirostrisand Bar-tailed GodwitLimosa lapponica). Several port configurations were developed on the basis of three design criteria: (1) create area for future port development, whilst (2) preserving existing high-value ecotopes for shorebirds and (3) enhance the natural accretion rate of such ecotopes. Simulation results showed a clear difference in siltation patterns, preservation and enhancement of preferred ecotopes. This work therefore demonstrates the potential and importance of morphological and habitat suitability modelling when designing large-scale reclamations and port constructions, especially in dynamic areas such as Tongzhou Bay

ICON.NL: coastline observatory to examine coastal dynamics in response to natural forcing and human interventions

In the light of challenges raised by a changing climate and increasing population pressure in coastal regions, it has become clear that theoretical models and scattered experiments do not provide the data we urgently need to understand coastal conditions and processes. We propose a Dutch coastline observatory named ICON.NL, based at the Delfland Coast with core observations focused on the internationally well-known Sand Engine experiment, as part of an International Coastline Observatories Network (ICON). ICON.NL will cover the physics and ecology from deep water to the dunes. Data will be collected continuously by novel remote sensing and in-situ sensors, coupled to numerical models to yield unsurpassed long-term coastline measurements. The combination of the unique site and ambitious monitoring design enables new avenues in coastal science and a leap in interdisciplinary research

Creating and rehabilitating salt marshes through Building with Nature: more than just compensation. A contractors perspective

Salt marshes have a variety of functions including ecosystem support, flood protection, water quality improvement and habitat enhancement. Depending on the goal of the project, the design and construction focuses on one or more of these functions. By using the concept of Eco System Services (ESS), the added value for the entire project can be evaluated. In the past years, several pilots and projects have been carried out in which the natural function of the (salt) marsh / wetlands is combined with flood protection and ecosystem enhancement. The aim was to search for a design that integrated hydraulics, morphology and ecology from the start and could subsequently fulfill more goals at a lower cost. In addition, the design focused on the utilization of the strengths and materials present in the natural system thereby effectively integrating the final project into the local surroundings. Design and subsequent implementation were achieved following the principles of Building with Nature. The presentation provides a brief overview of the Building with Nature approach used, and then describes how it is implemented in practice using several case studies. In the case studies, it zooms in on which designs were considered and used, how they integrate the functions and importantly how the projects were constructed. Examples include: Sand engine project (the Netherlands): using the natural forces of the coastal system to ensure long term maintenance of the Dutch Coast at lower cost Houtribdijk pilot project (the Netherlands): investigating various foreshore designs and materials (including vegetation) to effectively protect existing of new dikes Cliff Pools bird sanctuary project: large scale pilot Wetland restoration/development using dredged material along the coast of the UK Markerwadden (the Netherlands) large scale wetlands creation using soft materials for nature and recreation development Pilot projects creating natural reefs and breakwaters using natural materials that are integrated into the (ecological) design (3D printed reefs, oysters, sand berms, etc) Wetland creation as an integral part of project design thus allows for beneficial re-use of dredged materials, hence contributes importantly to the sustainable development of marine infrastructure projects

The influence of the Sand Engine of the Delfland coastal cell

The Sand Engine is an example of a feeder nourishment that is intended to nourish coastal systems. This strategy is based on placing sediments highly concentrated at one location, from which it is expected to spread alongshore over large distances on decadal timescales. Here the morphological development of the Sand Engine mega feeder nourishment and the adjacent coastal sections is presented. This study is based on 37 high-resolution topographical surveys, spanning a coastal cell of 17 km alongshore. These data are explored to examine the alongshore spreading in the first five years after construction in 2011, as well as the response at different depth contours in the coastal profile. The analysis shows that the highly concentrated nourishment supplies sediment to a stretch of coast that is several times the initial length of the nourishment, as the size of the Sand Engine peninsula increased from 2.2 to 5.8km alongshore. The plan-form shape of the peninsula is found to gradually extend alongshore, while reducing in cross-shore extent. This behaviour is found to vary strongly with depth contours. The strongest response was found around the mean sea level iso-bath in contrast to the deeper parts and Aeolian parts of the Sand Engine. This variability in response over depth results in different profile slope development in accretive and erosive areas. In coastal sections which are eroding the sub-tidal slope decreases, while accretive profiles experience a profile slope increment over time. The cross shore extent of the morphologic response shows limited morphodynamic activity below the -8m NAP depth contour and confirms earlier assessments of closure depth at this coast. The current findings at the Sand Engine imply that mega feeder nourishments can be beneficial to the sediment budget of a larger coastal cell. However, volumes that are deposited around or below the depth of closure (around 15 % for the Sand Engine) may react on much longer time-scales than intended. Therefore, the feeding characteristics of mega feeder nourishments on time-scales of years should be assessed using the nourished volumes above the depth of closure rather than the total volume.Abstract to the presentation held on the NCK days 2018 in Haarlem, the Netherlands.status: publishe

A six month high resolution 4D geospatial stationiary laser scan dataset of the Kijkduin beach dune system, The Netherlands

In Kijkduin (The Netherlands) a Riegl terrestial laserscanner on top of a building has surveyed a kilometer of beach and dune from November 2016 to May 2017. More than 4000 hourly and daily scans were obtained during this period containing between 1 and 10 million points per epoch with a decimeter order point spacing and centimeter order vertical accuracy. The dataset was collected within the CoastScan project (Vos et al., 2017) which aims to study the natural variability and resilience of the coast and the use of near-continuous laserscanning to study various spatiotemporal processes simultaneously. The dataset contains 4082 individual scans with supporting files to obtain georeferenced and time corrected point clouds in the Dutch national coordinate system