This paper describes an experiment with the objective to examine the utility of Landsat TM for estimation of chlorophyll-a, in and close to an outfall plume; in this case a plume from a pulp and paper industry. The principal findings were that the near-infrared band TM4 was independent of the high load of total suspended matterin the plume, but strongly correlated to chlorophyll-a concentrations in the surface water layer. The effect of the industrial effluents on algal production was negligible, or only slightly positive. These results have implications for on-going efforts attempting to identify and rank pollution sources around the Baltic sea and their specific effect on primary production.