Aeration Systems for Large Navigable Rivers

River aeration systems, using only slight modifications of commercially available components, appear to offer a very economical means of achieving dissolved oxygen standards on major rivers. Whether surface aerators or bottom air diffusers are applicable to a given site depends primarily upon requirements of navigation. Spacing of aerator sites would require an analysis of dispersion characteristics and biochemical-oxygen-demand regimen. On critical areas of the Delaware estuary costs of obtaining the last milligram per liter of dissolved oxygen by river aeration are estimated to be less than one-third of the cost of obtaining the same objective through waste treatment only. There is a possibility that even lesser costs could be realized through use of pure oxygen dispersers, but these possibilities do not appear to have been fully explored.