There are a number of environmental stressors associated with the operation of offshore net pen aquaculture facilities that pose impact analysis challenges for related consent processes. A selection of example approaches are presented where integrated modeling was used to determine the spatial and temporal magnitude of the impact or risks associated with:
DHI have carried out numerous studies of the deposition of fecal matter and residual feed impacts by applying calibrated and validated 3D deposition modeling techniques. This typically entails integration of a MIKE 3 FM Hydrodynamic, MIKE PT, and MIKE ECO Lab - open equation solver - water quality models. The methodology includes 3D hydrodynamic (HD), particle tracking, and biogeochemical modeling of the deposition, transport and mineralization of organic matter covering several sequential production cycles (see figure 1).
The dispersal of pharmaceutical/therapeutic dosing for open cage aquaculture can be approached with different levels of modeling complexity, integrating the capabilities of a MIKE 3 FM hydrodynamic and MIKE ECO Lab to model the dispersion of pharmaceuticals, therapeutics, and antifouling agents. The approach can rely on more robust advection dispersion and substance decomposition modeling techniques or be adapted to consider additional environmental complexities.
The dispersal of copepodite larvae from salmon lice net pen aquaculture is a representative example of integrated disease transmission impact and management related modeling. Carried out initially at a project level, with follow-up development of a regional web-accessible operational system, the modeling allows for an analysis of both dispersal and infection (see figure 2). The web system is based on extensive data collection combined with HD and agent-based modeling (MIKE ABM Lab).