Water is treated with chloramines instead of chlorine
The City of Sierra Madre is preparing to temporarily change the source of water supply residents are receiving. Beginning on September 16, 2013 the source of water will change from local groundwater to imported water from San Gabriel Valley Municipal Water District (SGVMWD). SGVMWD will provide imported treated surface water produced by the Metropolitan Water District of Southern California (MWD). The change to MWD water supplied by SGVMWD is necessitated by the seriously reduced local groundwater levels resulting from several years of dry weather conditions according to a press release sent out last week. MWD is a fully permitted water system to treat and distribute treated surface water.
The change of water supply source from local groundwater to MWD water will result in changing the disinfectant in the water from the chlorine used now to the chloramines used by MWD. Chloramine treatment is not new, as chloramines have been used for disinfection purposes for many years and are considered effective disinfectants. It is encouraging to note that complaints of tastes and odors have been found to decrease in many systems after the use of chloramines begins.
Chloramines do not pose a health hazard to the general population. However, they can be a serious problem to individuals with kidney disease undergoing dialysis treatment on artificial kidney machines unless the chloramines in the treatment water are reduced to acceptable levels. We have been working with the State and County Health Department to ensure that everyone involved with the treatment of dialysis patients is alerted and that proper precautions are taken. If you are a dialysis patient receiving dialysis in your home, please contact your dialysis provider.
Chloramines, like chlorine are toxic to fish. Therefore, anyone putting fish into the water obtained from our supply should ensure that the fish are properly protected. Local pet and fish shops should be contacted to determine the best measures to cope with a chloraminated water supply. Holding the water for a period of time before using with fish may work well with chlorine, but is not a reliable procedure with chloramines which are able to persist much longer.
More information:
http://water.epa.gov/lawsregs/rulesregs/sdwa/mdbp/chloramines_index.cfm
http://www.epa.gov/ogwdw/disinfection/chloramine/pdfs/Q1.pdf
