ETS Worldwide Ltd

ETS holds a trademark for its unique EcoTrace™ patented technology. ETS is a world leader in the field of artificial tracer design and its’ manufacture, deployment and analysis. ETS has completed more than 200 contracts for 70 clients in the UK, EU, USA, Australia and, New Zealand. Clients include: US Army Corps of Engineers, government agencies and regulators, Consultants, port authorities and Research Institutions. Globally over 85 of these contracts have involved working on sediment transport studies for both sand and silt sized particles for numerous applications such as soil ground characterisation, overflow plume dispersion and fate assessments and environmental impacts associated with coastal activities including dredging and beach nourishment.   

ETS through the use of tracers can provide unequivocal and tangible data on actual sediment transport on a site-specific basis. ETS’ environmentally benign EcoTrace™ sediment tracers are manufactured in many different fluorescent colours and varying composition (particle size distribution and density) to match the target species. The tracer are then placed into and disperse within the natural environment and assimilate all of the complex key sediment transport processes due to tidal currents, wind-driven circulation and wave including erosion, resuspension, transport and deposition as well as bedform, entrainment, burial etc. and respond to the prevailing metocean conditions. Multiple silt and sand tracers can be used simultaneously to track sediment from different dredging and disposal operations and transport can be assessed over many months and 10’s km2. Furthermore, as a known quantity of tracer is released, a mass budget can be carried out to assess significance of the amount of tracer detected in sediment samples over they study site. The ability to determine the significance is especially beneficial for assessing the impact on sensitive environments such as coral reefs.

Using the sediment tracers ETS can conduct a study to calibrate a numerical model (to assess in detail the above processes to refine or adjust the assumptions made in the model) and/or provide a dataset for specific conditions to validate a model. The tracers are able to establish what sediment size fraction actually moves or does not move during specific hydraulic conditions which often sediment transport models are not able to correctly simulate. Current numerical sediment transport models cannot accurately reflect the actual erosion-resuspension processes or settling-deposition processes for different sediments instantaneously or spatially, mimic bedform or the cyclical nature of sediment erosion, transport and settling due to tidal currents. Models often assume that sediment is transported either permanently in suspension or permanently as bedload whereas in real-life it is much more cyclical temporally and spatially. As a results typically, numerical models either significantly under or overestimate the extent and timescales of sediment transport.