Nature-based solutions (NBS) bieden veel kansen om de waterveiligheid te verhogen en tegelijkertijd natuurwaarden te versterken. In dit artikel worden zowel een aantal ecologische en juridische aspecten besproken als de consequenties van NBS in voorlanden tussen dijk en water, ten behoeve van het overstromingsrisicobeheer.
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Stormwater runoff can contain high amounts of Potential Toxic Elements (PTE) as heavy metals. PTE can have negative and direct impact on the quality of surface waters and groundwater. The European Water Framework Directive (WFD) demands enhanced protection of the aquatic environment. As a consequence, the WFD requires municipalities and water authorities to address the emissions from drainage systems adequately and to take action when these emissions affect the quality of receiving waters together with mitigating the quantity challenges in a changing climate (floodings and drought). NBS is the most widely used method for storing stormwater and infiltrating in the Netherlands. However, there is still too little knowledge about the long-term functioning of the soil of these facilities. The research results are of great importance for all stakeholders in (inter)national cities that are involved in climate adaptation. Applying Nature-Based Solutions (NBS), Sustainable Urban Drainage Systems (SuDS) or Water Sensitive Urban Design (WSUD) are known to improve the water quality in the urban water cycle. The efficiency of NBS, such as the capability of bio swales to trap PTE, highly depends on the dimensions of the facility and on its implementation in the field [Woods Ballard, B et al, 2015]. For the determination of the removal efficiency of NBS information about stormwater quality and characteristics is essential. Acquiring the following information is strongly advised [Boogaard et al. 2014]:1. stormwater quality levels (method: stormwater quality database);2. location of NBS (method: mapping NBS in international database);3. behaviour of pollutants (method: cost effective mapping pollutants in the field). Stormwater quality contains pollutants as heavy metal in higher concentrations than water quality standards dictate. Over 500 locations with bio swales are mapped in the Netherlands which is a fraction of stormwater infiltration locations implemented in 20 years’ time. Monitoring of all these NBS would acquire high capacity and budget from the Dutch resources. This quick scan XRF mapping methodology of topsoil will indicate if the topsoil is polluted and whether the concentrations exceed national or international standards. This was only the case in one of the youngest pilots in Utrecht indicating that there are multiple factors other than age (traffic intensity, use of materials, storage volume, maintenance, run off quality, etc.). Several locations show unacceptable levels, above the national thresholds for pollutants where further research on the prediction of these levels in relation to multiple factors will be the subject of future research.The results of study are shared in 2 national workshops and valued as of great importance for all stakeholders in (inter)national cities that are involved in implementation of NBS for climate adaptation. The Dutch research results will be used to update (inter-)national guidelines for design, construction and maintenance of infiltration facilities this year. Stormwater managers are strongly advised to use this quick scan method within the first 10 years after implementation of swales to map possible pollution of the top soil and prevent pollution to spread to the groundwater in urban areas.
ClimateCafé is a field education concept involving dierent fields of science and practice for capacity building in climate change adaptation. This concept is applied on the eco-city of Augustenborg in Malmö, Sweden, where Nature-Based Solutions (NBS) were implemented in 1998.ClimateCafé Malmö evaluated these NBS with 20 young professionals from nine nationalities and seven disciplines with a variety of practical tools. In two days, 175 NBS were mapped and categorised in Malmö. Results show that the selected green infrastructure have a satisfactory infiltration capacity and low values of potential toxic element pollutants after 20 years in operation. The question “Is capacity building achieved by interdisciplinary field experience related to climate change adaptation?” was answered by interviews, collecting data of water quality, pollution, NBS and heat stress mapping, and measuring infiltration rates, followed by discussion. The interdisciplinary workshops with practical tools provide a tangible value to the participants and are needed to advance sustainabilityeorts. Long term lessons learnt from Augustenborg will help stormwater managers within planning of NBS. Lessons learned from this ClimateCafé will improve capacity building on climate change adaptation in the future. This paper oers a method and results to prove the German philosopher Friedrich Hegel wrong when he opined that “we learn from history that we do not learn from history”
The Dutch main water systems face pressing environmental, economic and societal challenges due to climatic changes and increased human pressure. There is a growing awareness that nature-based solutions (NBS) provide cost-effective solutions that simultaneously provide environmental, social and economic benefits and help building resilience. In spite of being carefully designed and tested, many projects tend to fail along the way or never get implemented in the first place, wasting resources and undermining trust and confidence of practitioners in NBS. Why do so many projects lose momentum even after a proof of concept is delivered? Usually, failure can be attributed to a combination of eroding political will, societal opposition and economic uncertainties. While ecological and geological processes are often well understood, there is almost no understanding around societal and economic processes related to NBS. Therefore, there is an urgent need to carefully evaluate the societal, economic, and ecological impacts and to identify design principles fostering societal support and economic viability of NBS. We address these critical knowledge gaps in this research proposal, using the largest river restoration project of the Netherlands, the Border Meuse (Grensmaas), as a Living Lab. With a transdisciplinary consortium, stakeholders have a key role a recipient and provider of information, where the broader public is involved through citizen science. Our research is scientifically innovative by using mixed methods, combining novel qualitative methods (e.g. continuous participatory narrative inquiry) and quantitative methods (e.g. economic choice experiments to elicit tradeoffs and risk preferences, agent-based modeling). The ultimate aim is to create an integral learning environment (workbench) as a decision support tool for NBS. The workbench gathers data, prepares and verifies data sets, to help stakeholders (companies, government agencies, NGOs) to quantify impacts and visualize tradeoffs of decisions regarding NBS.
Climate change is increasing the challenges for water management worldwide. Extreme weather conditions, such as droughts and heavy rainfall, are increasingly limiting the availability of water, especially for agriculture. Nature-Based Solutions (NBS) offer potential solutions. They help to collect and infiltrate rainwater and thus play an important role in climate adaptation.Green infrastructure, such as rain gardens (sunken plant beds) and wadis (sunken grass fields for temporary storage of rainwater), help to restore the urban water balance. They reduce rainwater runoff, stabilize groundwater levels and solve problems with soil moisture and temperature. Despite these advantages, there is still much ignorance in practice about the possibilities of NBS. To remedy this, freely accessible knowledge modules are being developed that can help governments and future employees to better understand the application of these solutions. This research, called GINA (Green Infrastructure in Urban Areas), aims to create more sustainable and climate-resilient cities by developing and sharing knowledge about NBS, and supports local governments and students in effectively deploying these green infrastructures.
Water quality is under pressure worldwide and requires urgent attention according to recent reports, calling for technological development and more cost-effective solutions. One such development is the use of nanobubbels (NBs). NBs have been gaining interest in both scientific and industrial fields over the past years due to their broad applicability and unique characteristics opposed to larger bubbles used in traditional applications, e.g. dissolved air flotation and aeration. NBs is promising in water technology applications, especially in aeration, as due to their small size they provide a large air-water interface and are stable (present in the bulk) for many days. Due to that, different companies have been introducing NBs based technology in the market. The start-up company BIMCO Holland is one of them. They have developed three types of Ultra Fine Bubble (UFB)-generators to integrate in various (household) applications: I) a tap connection for water taps, II) a pipe adaptor for household appliances and III) a shower coupling. In order to prove their concept, BIMCO Holland wants to test the UFB-generators together with NHL Stenden. During these tests, the intended formation of NBs in tap water will be determined, as well as possible effects on the water quality. Additionally, potential applications will be (theoretically) explored, such as reduced water- and surfactant usage and prolonged lifetime of materials and appliances. With NanoBGen, the consortium aims to understand better the functioning of the newly developed UFB-generators. The tests are required to prove the system is (or not) related to the presence of NBs. Also, to support the company finding other applications of the UFB-generators and contribute to bringing the technology to a higher TRL.
