Dear Koi Enthusiast: This email is an attempt to advise you of changes that may occur in your municipal water supply that may effect you. The Metropolitan Water District of Southern California provides treated water with a chloramine disinfectant residual to cities and water districts throughout the southland. Some communities receive all or only part of their water supply from Metropolitan. The current level of chloramines leaving Metropolitans filtration plants is 1.7 parts per million (mg/L). On June 1, 1998, Metropolitan anticipates increasing the chloramine residual to 2.5 parts per million leaving our filtration plants. Metropolitan is providing this information to inform you of the upcoming change, and to advise you to evaluate your water treatment methods to insure that your fish will be protected. Attached is some general information regarding the chloramine increase. If I can provide any further information regarding this change, please contact me via email, or call me at (909) 392-5011, or contact your local water provider to determine if they receive chloraminated water from Metropolitan. As our contacts with similar organizations are limited, please pass this message along to any of your associates. Thank you. David Foust Engineering Technician III Water Quality Division Metropolitan Water District of Southern California dfoust@mwd.dst.ca.us FREQUENTLY ASKED QUESTIONS ABOUT THE WATER QUALITY IMPROVEMENT PROJECT Are Chloramines New? No. Many cities in the U.S. and Canada have used chloramines for decades at much higher levels than Metropolitan. Metropolitan has been consistently using chloramines since 1985. Why is Metropolitan Increasing the Chloramine Level? The reason is to help your retail water supplier consistently deliver water to you with the lowest possible levels of trihalomethanes (THMs) and to provide better protection against the growth of bacteria within the water distribution systems of water suppliers. What are Trihalomethanes (THMs)? THMs are chemical compounds that are formed when chlorine mixes with naturally occurring organics in water. The U.S. Environmental Protection Agency (EPA) conducted tests which determined that chloroform (one of the THMs) is carcinogenic when consumed by laboratory animals in large quantities over a prolonged period of time, and is a suspected carcinogen for people. EPA set a standard of 100 parts per billion as the maximum level of THMs in drinking water in 1979. After additional research, the EPA has decided to lower the standard to 80 parts per billion effective November 1998. Will Metropolitan Meet the New Standard? Yes. However, a few suppliers within Metropolitan's service area may exceed the new EPA standard if they continue to use chlorine alone as a disinfectant. Exactly what service area are we talking about? Portions of all six counties, Ventura, Los Angeles, Orange, Riverside, San Bernardino, and San Diego. Are Chloramines Safe? Yes. Chloramines have been used safely in the United States and Canada for many years. EPA accepts chloramines as a disinfectant and as a way to avoid THM formations. Were it not for some kind of disinfectant in drinking water, disease-causing organisms such as typhoid and cholera could be carried in your drinking water. Chloraminated water is safe for bathing, drinking, cooking and all uses we have for water every day. However, there are two groups of people who need to take special are with chloraminated water: kidney dialysis patients and fish owners. Will The Increase in Chloramines Change the pH of Water? No. It will remain the same (pH = 8.0 to 8.4) Will I Notice a Taste Difference With The Higher Level of Chloramines? If you notice any change at all, you may find the water has less of a chlorine odor or taste. Will Increasing the Chloramine Level Increase the Cost of Water? No. The low increase in cost will be absorbed by Metropolitan. In fact, many agencies may realize a cost savings by eliminating to add further disinfection within their own systems because the chloramines will last longer. Do Home Water Softeners Remove Chloramines? Most water softeners are not designed to remove chloramines. Does Bottled Water Have Chloramines? It could. If the bottled water company uses water supplied by Metropolitan, then the water it provides will have chloramines in it, unless the company takes special steps to remove them. Do Chloramines Affect Swimming Pools? No. You will still need a free-chlorine residual to retard algae and bacteria growths. DPD test kits measure free-chlorine residuals and can be used with confidence. You should contact your local pool supply store for more specifics. How About Using Chloraminated Water on Ornamental Plants, Vegetables or Fruit and Nut Trees? Will Beneficial Soil Bacteria Be Harmed? The small amount of chloramines should have no effect on plants of any type. Beneficial bacteria will generally be protected by the soil in which they live. Chloramines will be removed by the high chlorine demand in the soil. How Do Chloramines Affect Fish? Chloramine are toxic to fish and must be removed from water, just as chlorine is toxic and must be removed. Most pet stores have sold dechlorinating agents for years and, generally, have recommended using them. The chemicals used to remove chlorine work just as well for chloramines. Several manufactures have been adding chloramine information on labels on their products for the Southern California market. Won't letting Water Sit for a Few Days Remove Chloramines From Tank or Pond Water? No. Unlike chlorine, which dissipates when water sits for a few days, chloramines may take weeks to disappear. If you don't want to use a dechloraminating chemical, the next best solution is to install a granular activated carbon filter allow sufficient contact time. If Only A Small Amount of Water is Added to an Aquarium or Pond to Make up for Evaporation Loss, Do Chloramines Still Have to be Removed? This will depend on the amount of water added in relation to the size of the aquarium or pond and the time period over which it's added. An alternative is to monitor for a total chlorine residual in the aquarium or pond water. Chloramines residuals in water used to keep fish should be below 0.1 mg/L. Total-chlorine test kits are available from pet stores, pool supply stores and chemical supply houses. Are Both Salt- and Fresh-Water Fish Affected By Chloramines? Chloramines will have to be removed if the water used to make the salt-water solution comes from an agency receiving water from Metropolitan. Chloramines affect salt-water fish just as they affect fresh-water fish. Can Koi Assimilate Chloramines, Unlike Other Fish? No. Koi are just as susceptible to chloramines as any other fish. Will a Carbon Filter Remove Chloramines? Yes. However, it must contain high-quality granular-activated carbon and you must permit sufficient contact time. New catalytic carbons (bituminus coal based) are available that are excellent in removing chloramines. Will Reverse Osmosis Remove Chloramines? No. Salts can be caught by the permeable membranes but chloramines pass through easily. How Much of a Dechlorinating Agent or What Type GAC Filter Should be Used? As your pet supplier or read the instructions on the container or equipment. What are the Effects of Ammonia on Fish? Ammonia can be toxic to fish, although all fish produce some ammonia as a natural byproduct. Ammonia is also released when chloramines are chemically removed. Although ammonia levels may be tolerated in individual tanks or ponds, commercial products are available at pet supply stores to remove excess ammonia. Also, biological filters, natural zeolites and pH control methods are effective in reducing the toxic effects of ammonia.