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DJ Ezell, Manager, (503) 635-6041

RIVERGROVE WATER DISTRICT TO BEGIN PERMANENT DISINFECTION OF WATER Starting October 24, 2012, the Rivergrove Water District began adding chlorine to its entire drinking water system. Up to this point, only a portion of the Rivergrove Water District water system (the “upper” pressure zone) was disinfected with chlorine. Disinfection of the entire system is being done for the following reasons: To address recent discovery of the presence of non-harmful coliform bacteria in the water system. To maintain water quality throughout the drinking water distribution system by killing potentially harmful organisms that may get in the water as it moves through the pipes. To prevent harmful organisms from getting in the water if a pipe breaks or a backflow condition occurs. To provide consistent water quality between the upper and lower pressure zones so drinking water can be transferred between the pressure zones. To eliminate additional drinking water testing requirements that would be required if the entire drinking water system is not chlorinated. To make emergency connections with the Cities of Tualatin and Lake Oswego more quickly and easily accessible under an emergency water supply situation. Following are answers to some frequently asked questions: 1. What is chlorine? Chlorine is a naturally occurring element that is commonly used as a disinfectant in drinking water. Since the early 1900’s, water systems in the United States have used chlorine to eliminate bacteria (a process called chlorination). Chlorine is used by most of the municipal drinking water suppliers across the country for disinfection of their water systems. For more information, go to this link:


2. What areas will be chlorinated? The entire water system will be chlorinated, affecting all customers that receive water service from the Rivergrove Water District. 3. How much chlorine will be in the water? Enough chlorine will be in the water to maintain a chlorine residual of 0.2 to 0.5 ppm (parts per million), equivalent to about 1 drop in 44 gallons of water. A typical swimming pool would have anywhere from 2.0 to 4.0 ppm of chlorine residual, roughly 4 to 10 times higher than typical drinking water. Many people will be able to smell or taste a small difference, but it will not be as strong as what is used in swimming pools. 4. What should I expect during chlorination? For most customers, there will be no noticeable change in drinking water quality. Chlorine has a distinct odor and may affect the taste of the water. However, these changes do not affect the safety of the water. During the initial disinfection implementation period, some customers may notice a discoloration of the water as the chlorine reacts with any organic and inorganic residue currently in the distribution system. Should you experience dirty or discolored water, please contact the District at (503) 635-6041 for assistance. 5. What can I do if my water smells or tastes like chlorine? Try setting a pitcher of water aside overnight (on the counter or in the refrigerator). The chlorine dissipates over time, so the smell and taste should be less noticeable. Inexpensive pitcher or faucet filter systems that remove chlorine are also available at home improvement centers. 6. How can I avoid skin reactions from exposure to chlorine? The level of chlorine is 4 to 10 times less than that found in a typical swimming pool. If your family members do not have reactions to swimming pools, bathing in this water should not cause a reaction. Inexpensive filters for showers or tubs that remove chlorine are available at home improvement centers. 7. What precautions should customers with home dialysis systems take? Customers with home dialysis systems should recognize that chlorine will be present in the water and their filter systems will need to be prepared accordingly. 8. What precautions should fish, aquatic life owners take? Chlorine should be removed from water that is used in fish tanks, ponds and aquariums. Water customers should treat water for use in aquariums with a dechlorinating conditioner,


available at many locations where pet supplies are sold. Businesses that sell, keep fish or other aquatic life in aquariums or ponds are encouraged to contact a pet supply company about how to treat their water to remove chlorine before using drinking water in an aquarium. Similarly, customers who use drinking water for aquaculture (growing plants in a water tank or pond) are encouraged to get expert advice regarding procedures needed to neutralize or remove chlorine. Also, restaurants and grocery stores that have aquatic life, such as live lobster tanks, must take special precautions to treat the water. 9. Will chlorination affect routine household uses? Chlorination will not affect routine water uses such as food preparation, household laundering, dishwashing, watering plants, etc. Chlorine will not have any effect on plants of any type, and will usually be removed by the naturally high chlorine demand of soil. 10. Will chlorination affect routine business water uses? Chlorination will not affect routine business water uses. However, businesses and other establishments that use municipal drinking water for commercial laundering operations, laboratory procedures and other processes in which water quality must be carefully controlled should obtain advice from equipment manufacturers or other suppliers regarding any process changes that may be needed. 11. Where should I go for more information? More information can be obtained from: Oregon Health Authority, Drinking Water Program Environmental Protection Agency Rivergrove Water District