Pollutants
The Ottawa River Risk Assessment, a report published in 2000, tested the water of the lower section of the Ottawa River, and found many chemicals in the water with an hazard quotient greater than 1 (from highest to lowest concentration): lead, aluminum, PCBs, manganese, iron, DDT, thallium, selenium, chromium, nickel, cadmium, cyanide, and zinc.
The reasons for the poor water quality are primarily its form and structure, since it has a slow flow, and, secondly, runoff and discharge from landfills and sewers. The City of Toledo has made it a priority to clean up the river, and action has been taken to clear landfills and tributaries.
Read more about this topic: Ottawa River (Lake Erie)