Paul Whitehead and colleagues have published a new version of INCA. INCA-Metals, to simulate the impact of point source metal discharges (e.g., from tannery wastes or acid mine drainage) and diffuse rural runoff on riverine water quality. The model accounts for the key chemical reaction kinetic processes operating as well as sedimentation, resuspension, dilution, mixing and redistribution of pollutants in rivers downstream of discharge points. The model is dynamic and simulates the daily hydrology and behavior of eight metals, including cadmium, mercury, copper, zinc, lead, arsenic, manganese and chromium, as well as cyanide and ammonia. Like all members of the INCA family, the model is semi-distributed and can simulate catchment, tributary and instream river behavior. The apply the new model to predict impacts of the Savar tannery complex on the Dhaleshwari River system in Bangladesh on pollution levels in the river system and to evaluate a set of treatment scenarios for pollution control, particularly in the dry season. They show that the new efﬂuent treatment plant at Savar needs to signiﬁcantly improve its operation and treatment capability in order to alleviate metal pollution in the downstream Dhaleshwari River System and also protect the Meghna River System that discharges into the Bay of Bengal.