The movement of water in the river. An oily spot on the water. Traffic and pedestrian traffic on a city street. Pedestrian feet, horse hooves, a moving cart wheel. Residential five-storey buildings. Construction waste near the dug trench. Children playing around a pile of rubbish. Fuel oil stains on the highway. Along the road there are two trenches filled with water and debris. Pillars scattered around the trench.