Disinfection of Water
Robert Hardt
Instructor Mark Schmidt
Surface Water Supply/Treatment
March 14, 2013
Disinfection
The main objective for the disinfection process raw water undergoes in our treatment facilities, rather the only purpose for disinfection is to kill any and all remaining viruses and harmful pathogens that would otherwise threaten the safety of those to consume it. Even after the turbidity has been reduced down to very nearly an ntu level of zero and the water is aesthetically sound in appearance, taste and a lack of any foul odor, invisible microorganisms capable of compromising the drinkability of the water are still almost always present and must be killed before the product is distributed to its customers. While there are several different chemical and nonchemical disinfection methods available for use throughout the water treatment industry including via means of chlorination, hypochlorination, and ultra-violet light (quickly increasing in popularity), a strict agenda of regulatory guidelines must be closely adhered to. These regulations have been implemented over the years by the federal Environmental Protection Agency and state entities under the Safe Drinking Water Act and other correlated laws, and protect consumers from adverse effects on human health potentially caused from water that has not been adequately disinfected. National Interim Primary Drinking Water Regulations (NIPDWR) were made effective nationally on June 24th of 1977, originally creating standards to be met by all treatment facilities in the U.S. Regulations regarding bacteria, turbidity, 10 inorganic constituents, 6 common pesticides, and radionuclides were then at that point to be regularly tested for, measured, documented and reported without exception. Since then, amendments to Interim Regulations have additionally required the monitoring and scheduled reporting of several maximum contaminant levels (MCLs) following disinfection processes, including requirements
Instructor Mark Schmidt
Surface Water Supply/Treatment
March 14, 2013
Disinfection
The main objective for the disinfection process raw water undergoes in our treatment facilities, rather the only purpose for disinfection is to kill any and all remaining viruses and harmful pathogens that would otherwise threaten the safety of those to consume it. Even after the turbidity has been reduced down to very nearly an ntu level of zero and the water is aesthetically sound in appearance, taste and a lack of any foul odor, invisible microorganisms capable of compromising the drinkability of the water are still almost always present and must be killed before the product is distributed to its customers. While there are several different chemical and nonchemical disinfection methods available for use throughout the water treatment industry including via means of chlorination, hypochlorination, and ultra-violet light (quickly increasing in popularity), a strict agenda of regulatory guidelines must be closely adhered to. These regulations have been implemented over the years by the federal Environmental Protection Agency and state entities under the Safe Drinking Water Act and other correlated laws, and protect consumers from adverse effects on human health potentially caused from water that has not been adequately disinfected. National Interim Primary Drinking Water Regulations (NIPDWR) were made effective nationally on June 24th of 1977, originally creating standards to be met by all treatment facilities in the U.S. Regulations regarding bacteria, turbidity, 10 inorganic constituents, 6 common pesticides, and radionuclides were then at that point to be regularly tested for, measured, documented and reported without exception. Since then, amendments to Interim Regulations have additionally required the monitoring and scheduled reporting of several maximum contaminant levels (MCLs) following disinfection processes, including requirements
References: Pizzo, N. (2010). M. Valentine (Ed.), WSO: Water Treatment (4th ed., pp. 188-216). Denver, CO: American Water Works Association. USEPA, (n.d.). Drinking water contaminants: National primary drinking water regulations. Retrieved from website: http://water.epa.gov/drink/contaminants/index.cfm USEPA, (n.d.). Current drinking water regulations. Retrieved from website: http://water.epa.gov/lawsregs/rulesregs/sdwa/currentregulations.cfm