Ключевые слова: background, canal, chemical, city, concrete, contaminated, contamination, corrosion, damage, danger, dirty, disaster, drain, drainage, dump, ecology, environment, environmental, factory, flow, flowing, garbage, green, industrial, industry, liquid, natural, nature, outdoor, outdoors, pipeline, plant, polluted, pollution, problem, river, rusty, sewage, sewer, social issues, stream, substance, toxic, trash, tube, unhygienic, urban, waste, water,