Water Pollution
Water is in its purest form the moment it condenses from vapor to liquid, but it easily picks up various impurities. Rain and snow can pick up dust, smoke and other particles in the air. Runoff water carries impurities, along with sediment, human-made pollutants and other contaminants into surface and groundwater.

A History of Purification
Water pollution is not a new problem. Since the early times of recorded history, people have created ways to remove debris from drinking water to make it look and taste better. Ancient Egyptian inscriptions describe water purification by boiling, exposing it to sunlight, charcoal filtration and letting it "settle" in an earthen jar. As early as 400 B.C., the Chinese discovered the purifying effect of boiling water.

It wasn't until the mid-1800s, however, when scientists suspected that disease could be spread through impure water.

Today's Pollution
Industrialization, urban development, deforestation and changes in agricultural practices have a major impact on the land. Fertilizers, insecticides and herbicides used on residential lawns contribute to pollution. Other matter such as fecal wastes from pets, grease and oils from the road and carelessly discarded garbage also contribute to pollution.

The three major sources of water pollution in the United States include discharges from industries and wastewater treatment facilities, urban runoff and agricultural runoff.

Southern Nevada's Water
Southern Nevada has a pristine water source in the Colorado River. The Safe Water Drinking Act requires the Environmental Protection Agency to establish national drinking water standards and to implement source water protection to help ensure the quality of water. Local treatment facilities are on the cutting edge of technology, ensuring that our water meets or exceeds all state and federal standards.

While the Southern Nevada Water Authority and governments at all levels continually ensure the safety of our drinking water, every resident shares the responsibility to protect water supplies locally and throughout the world.