Across the world, countries are struggling to keep drinking water clean. Be it streams, rivers or lakes, countries have taken great measures to maintain high-quality drinking water for both human and animal consumption. Countries must first understand the sources of the pollution, then determine the best methods to eliminate the pollution. Clean drinking water is a precious resource and the key to human survival. Plants and animals also depend on water for their growth, so all water must be kept clean. The main causes of water pollution can be classified into three categories: industrial, agricultural and municipal. Examples of industrial wastes that can contaminate bodies of water include oil spills, acid rain, and waste runoff from industrial buildings and factories. Oil spills, while they don't happen that often, can spill millions of gallons of crude oil into the ocean causing long-term damage. The oil spreads across the surface of the water, creating a deadly coating. It kills fish and animals and washes up on the coasts, polluting the beaches and closing them to the public. Once the oil has contaminated the water, immediate measures must be taken to clean it from the water. The most common procedure is to contain the oil with absorbent plastic barriers and then skim the oil from the surface of the water. Industrial waste or runoff from factories can pollute waterways near the dumping site. Oils, inorganic mine...