The effects vary on the chemicals and other pollutants that enter the water the worst is that the water is posined and can kill thecosystems in the water that can cause humans to lose a massive food supply to humans. The others are that it can render our water undrinkable that can become a very big promblem to us. Many lakes pomds near urban areas (cities and towns) are highly polluted. This is the result of both garbage dumped by individuals and dangerous chemicals legally or illegally dumped by manufacturing industries, health centers, schools and market places.