Turbidity

Solid particles suspended in water absorb or reflect light and cause the water to appear "cloudy." These particles are undissolved inorganic minerals or organic matter picked up over or under the ground. Since the earth acts as an excellent filter, the water from deep wells is usually clear without significant amounts of turbidity. This problem is more common in the water from surface supplies.

The major problem with turbidity is aesthetics, but in some cases suspended matter can carry pathogens with it (Turbidity in surface waters: indicate Cryptosporidia!). Large amounts of organic matter can also produce stains on sinks, fixtures, and laundry. Much like iron, organic matter in water may also produce colors, unpleasant tastes, and odors. These tastes and odors will affect not only drinking water, but the foods and beverages prepared with the water.