Outfall mixing in shallow coastal water under arctic ice cover

The continuous release of pollutants in shallow coastal water under ice cover is considered. Shallow depth, boundary roughness and low ambient velocities and diffusivities combine to severely restrict the dilution capacity of such sites. A depth-averaged steady-state near-field model for single port jet discharge in ambient coflow is developed. The dissipation of discharge momentum through boundary friction puts a limit on the achievable near-field mixing. The near-field model is combined with a far-field diffusion analysis to provide overall mixing zone predictions for a discharge in a shallow lagoon in the Beaufort Sea.