CITY OF RENTON WASHINGTON

Approximately 87 percent of Renton's water is supplied by the Cedar Valley Aquifer, with the rest coming from Springbrook Springs, located in south Renton.

As Renton's primary water source, the Cedar Valley Aquifer has been designated a "sole source" by the U.S. Environmental Protection Agency. This means that no federal financial assistance can be given to a project which might contaminate the aquifer and create a public health hazard.

The aquifer is an underground layer of sand and gravel running 3 1/2 miles long and furnishing Renton residents with an average of 7.3 million gallons of water each day. At some points, the groundwater contained in our aquifer is only 23 feet below ground, making it very sensitive to pollutants.

Protecting our aquifer is important to keep our water clean.

Beginning in April 2016, the city lowered the fluoride level in the water system to 0.7 ppm with an operating tolerance of 0.5 ppm to 0.9 ppm to comply with the Washington State Board of Health's adoption and update of WAC 246-290-460, which established a new fluoride optimization level of 0.7 ppm effective May 9, 2016.

A vote in November 1985 directed Renton to fluoridate its drinking water, which began in February 1987.

Renton provides water to over 64,000 residents and on a wholesale basis to Skyway Water and Sewer District.

Natural disasters such as a storm or an earthquake can cut off drinking water supplies with no warning.

Planning for such a possibility will assure there is safe drinking water available. To prepare for a drinking water emergency, the American Red Cross recommends storing one gallon of water per person per day (two quarts for drinking and two quarts for food preparation/sanitation). Store at least three days worth, and if possible, store a two week supply for each family member.

Store water in food grade containers or in plastic soft-drink bottles. Do not use plastic jugs or cartons that have had milk or juice in them as they cannot be adequately cleaned to prevent bacteria growth. Also, avoid glass containers as they can break in a disaster.

Store water in a cool place that will be safe from disaster and discard and replace the stored water every two to six months.

In a disaster, if a safe supply of water is not available, any suspect water should be treated by either boiling or adding bleach. If the water is cloudy, it should be filtered before boiling or adding bleach. This can be done with camping filters made for this purpose or by running the water through coffee filters, paper or cotton towels, or cheesecloth.

Boiling water is the best way to purify unsafe water because of the presence of protozoan parasites or bacteria. Heat water to a full boil in a clean metal pan for at least three minutes. Keep it covered while it cools, then store in clean containers.

Lead in drinking water is a concern that concerns many residents.

Renton’s drinking water comes from wells and is lead free as it begins its journey to the tap. The water is conditioned by adding sodium hydroxide to slightly raise its pH which helps prevent corrosion of household plumbing.

Renton regularly tests for lead at the household taps and has never had a high reading. The threat of lead is extremely low and dependent on household plumbing.

Residents concerned about older plumbing should follow Washington State Department of Health guidelines for reducing lead exposure in drinking water:

• Homeowners living in housing built before the mid-1940s should run the tap at least two minutes after water has sat in the pipes for six hours or more. This will help flush out any lead that may have accumulated.

• Homeowners living in newer housing and concerned about lead, should flush the pipes by running tap until the water is noticeably cooler.

• Use only cold water for drinking, cooking, and making baby formula. Hot water may contain higher levels of lead.

• Clean the screens and aerators in faucets frequently to remove captured lead particles.

• Use only “lead free” piping and materials for plumbing when building or remodeling.

The water pumped from the downtown wells and Springbrook Springs sources is very clean and needs minimal treatment.

Chlorine, which destroys bacteria and viruses, is added to make sure the water stays clean on its way to the customers. Fluoride is also added to prevent tooth decay. In the areas of Renton Hill, Talbot Hill, and West Hill, ortho polyphosphates are added to the water to reduce corrosion of the iron water pipes found in these neighborhoods.

The Maplewood wells water is also very clean, but because of its natural mineral content and pH, it must first be treated before it can be co-mingled with the water from the other sources. This treatment process consists of the removal of manganese, hydrogen sulfide, and ammonia from the raw water. Chlorine is added for secondary disinfection and fluoride to prevent tooth decay.