But it wasn’t always so simple …
The story of water begins thousands of years ago in prehistoric times. Even then people built their homes on lakeshores or along rivers so they had water to drink and wash in, and so they could travel easily from place to place. These waterways contained some contamination, but the water was probably cleaner because pollutants produced by industrialization and population growth had not yet affected water sources.
The ancient Asians were the first to record methods for purifying water. In about 2000 B.C., the Asians kept water in copper vessels, exposing it to sunlight, and filtering it through charcoal. Greek physician Hippocrates, who lived from 460-354 B.C., wrote about how to purify water. After boiling rain water, he made a “Hippocrates’ sleeve,” a cloth bag for straining the rain water. Egyptian records dating to 400 A.D. indicate that the most common ways of cleaning water were boiling it over a fire, heating it in the sun, or dipping a heated piece of iron into it. Filtering boiling water through sand and gravel and allowing it to cool was another common treatment method.
Other ancient people, including the Anasazi in North America, the Mayans in Central America, the Inca of South America, and the Romans in Europe, developed clever ways to capture and transport clean water to their communities. Through diversion dams and aqueducts, people found ways to ensure that they had adequate supplies of water for washing, drinking, and growing food.
Water treatment and distribution today use some of these same techniques but are more complex.
For the majority of Skagit PUD customers, rainwater and melted snow are collected throughout the year from streams in the area surrounding Judy Reservoir and from the Skagit River, and then stored in the reservoir for use by customers. The stored water is pumped to the water treatment plant where impurities are removed.
Chemicals are added to the water to remove particles and provide disinfection. The water is then gently mixed in open basins that provide for the chemicals to react with the water. The water then passes through one of four filters. The filter media consists of a layer of sand and coal supported on gravel where impurities are trapped.
After filtration, the water is disinfected once again and then flows by gravity to two steel storage reservoirs, called clear wells, near the treatment plant. The clean water then flows into the distribution system and eventually arrives at your home safe to drink.
SOURCE: The Story of Drinking Water, AWWA; 2011.
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