Ключевые слова: background, bacterium, channel, chemical, clean, concrete, culvert, dirt, dirty, ditch, drain, drainage, dump, ecology, environment, environmental, factory, flow, flowing, flume, green, ground, industrial, industry, liquid, natural, nature, outlet, plant, pollution, polution, sanitary, sewage, sewerage, slop, stream, toxic, trash, treatment, waste, water, weir,