Otherwise nontoxic, conventional pollutants, such as dirt, can contaminate a water body by making the water unusable for drinking and swimming, and ultimately destroying fragile aquatic life
Substances, which are biodegradable (i.e., bacteria can break them down), occur naturally in the aquatic environment, and, in large amounts deplete the dissolved oxygen concentration in water, which is necessary for the survival of fish and other aquatic life. These pollutants include suspended solids, biochemical oxygen demanding materials, oil and grease, fecal coliform, and pH.