Matching Pairs Water Pollution VocabularyOnline version Matching vocabulary. by Anna Rowe 1 Nutrient Pollution 2 Water Pollution 3 Sediment Pollution 4 Toxic Pollution 5 Bacterial Pollution The introduction of harmful substances into the water. the presence of excess nutrients in the water. the presence of toxic substances in water. the presence of excessive sediments such as silt and clay in water. the presence of harmful bacteria in water supplies.