Assessing the influence of floating constructions on water quality and ecology
Rui L. P. de Lima, Indymo
Floris C. Boogaard, Hanze University of Applied Sciences, Indymo, Deltares
Large floating projects have the potential to overcome the challenge of land scarcity in urban areas and offer opportunities for energy and food production, or even for creating sustainable living environments. However, they influence the physical, chemical, biological and ecological characteristics of water bodies. The interaction of the floating platforms affect multiple complex aquatic processes, and the potential (negative/positive) effects are not yet fully understood. Managing entities currently struggle with lack of data and knowledge that can support adequate legislation to regulate future projects.
In the Netherlands the development of small scale floating projects is already present for some years (e.g. floating houses, restaurants, houseboats), and more recently several large scale floating photovoltaic plants (FPV) have been realized. Several floating constructions in the Netherlands were considered as case-studies for a data-collection campaign.
To obtain data and images from underneath floating buildings, underwater drones were equipped with cameras and sensors. The drones were used in multiple locations to scan for differences in concentrations of basic water quality parameters (e.g. dissolved oxygen, electrical conductivity, algae, light intensity) from underneath/near the floating structures, which were then compared with data from locations far from the influence of the buildings. Continuous data was also collected over several days using multi-parameter water quality sensors permanently installed under floating structures.
Results show some differences in concentrations of water quality parameters between open water and shaded areas were detected, and some interesting relations between parameters and local characteristics were identified. Recommendations are given, in order to minimise the undesired impacts of floating platforms. Considering the complexity of the interactions between water quality parameters and the influence of the surrounding environment it is recommended to continue and to improve the monitoring campaign (e.g. include new parameters).
Keywords – Water Quality, Ecology, Environmental impacts, Monitoring tools, Aquatic drones
Rui Lima holds a MSc in Civil Engineering (Hydraulics, Water Resources and Environment specialization) from the University of Coimbra, in Portugal. He currently works at the Dutch Startup INDYMO on the development of innovative applications of technology in water management, including unmanned remote-controlled and autonomous vehicles that are equipped with sensors and cameras and then used to collect environmental data. Before INDYMO, he was a researcher at Deltasync where he conducted studies on the potential of floating cities for sustainable food and energy production, and at a Portuguese water board. He's currently pursuying a PhD about innovative monitoring techniques, and the receptivity of water managers towards new tools and technologies.