Pollutant transport modelling

Introduction Modelling pollutant transport is an established tool for the design of remediation strategies intended to reduce impairment of both fresh and marine waters by anthropogenic inputs of infectious agents and/or toxic chemicals. Examples can be seen in the design and calibration of near-shore hydrodynamic and water quality models designed to limit microbial and chemical pollution of bathing and shellfish harvesting waters. Parallel models of terrestrial drainage basins are deployed to provide input data for the near-shore systems and these often address both the riverine systems and their contributing catchment areas and the artificial sewerage network, removing foul effluent and surface waters away from urban areas and delivering this flow to waste water treatment plants. These river and network models are generally treated as discrete systems but the network models are often used to provide modelled flows of treated effluent discharged to the river and/or local coastal waters. This demand for pollution transport models has produced an industry of consultancies building generic model platforms which are available to the designers of specific improvement schemes as well as utilities and regulators responsible for delivery

of legally required environmental standards. Catchment and near-shore models are often integrated as modules in a family of modelling tools as is seen in the Danish Hydraulics Institute’s Mike 11 (river catchment1), Mike Urban (network modelling) and Mike 21 (near-shore) commercial modelling products.