By Kelly A. Reynolds, MSPH, Ph.D.
Consumers need better assurances that the water they’re supplied isn’t tainted with disease-causing contaminants. According to a survey by the Water Quality Association, more than 50 percent of Americans worry about impurities in their tap water. This isn’t surprising since the Center for Disease Control (CDC) estimates that 1 million people in the United States become sick each year from consuming contaminated water.
During a 1994 meeting of the American Academy of Microbiology, it was projected that “water treatment technologies, if adequate, are often not applied, are poorly applied, or are not sufficiently monitored and controlled. Inadequate, interrupted or intermittent treatment has repeatedly been associated with waterborne disease outbreaks.”1 This statement reflects that even the best available technology for water treatment is plagued by failures in the system or improper regulation, monitoring and control. The U.S. Environmental Protection Agency (USEPA) Science Advisory Board concluded in 1990 that drinking water contamination is one of the highest environmental risks to human health.3
In response to the worsening water quality problem and decrease in consumer confidence, the USEPA has drafted (these may not be set in stone yet) specific milestones as goals to aim for by the year 2005 relating to drinking water quality:2
- The population served by community water systems in violation of health-based
requirements will be reduced to 5 percent (compared to 19 percent in 1994).
- Every person served by a public water system that draws from an inadequately
protected river, lake or reservoir will receive drinking water that’s adequately filtered—393 systems serving 9.9 million people didn’t meet all Surface Water Treatment Rule (SWTR) requirements for having filtration treatment in place for surface waters as of 1995.
- Ninety percent of the nation’s river and stream miles and lake and reservoir acres
designated as drinking water supplies will provide water that’s safe to use after conventional treatment as compared to 84 percent deemed safe in 1994.
- Sixty percent of the population served by community water systems will receive their
water from systems with source water protection programs in place (compared to only 5 percent of the population in 1993).
A status report on the USEPA’s progress in achieving these goals by 2005 is not currently available. And regardless of the improvements in a water system’s ability to treat and provide safe drinking water to consumers, the quality of water supplied is only as good as the quality of its subsequent distribution system. Deteriorated distribution piping allows water to become contaminated in the distribution system. According to a 1997 USEPA report to Congress, significant upgrades and repairs are needed throughout the country (see WC&P, “U.S. Water Infrastructure Needs,” August 1999, p. 76)
Consumer water demands
How much water do individuals consume each day? Figure 2
Ground vs. surface water
The National Ground Water Association reports that in 1995, 76.4 billion gallons of water each day were utilized from a groundwater source in the United States from 15 million groundwater wells.5 The percent of the public-supplied population served by groundwater in 1990 was highest in Florida, Mississippi, Nebraska, South Dakota and Idaho, serving
Recent studies by the USEPA indicate that a substantial number of groundwater sources show evidence of fecal contamination. The primary source of groundwater contamination has been listed as septic tanks that serve 25 percent of the U.S. population. Figure 5 shows the percentage of ground water source systems citing water contamination sources.
Developing contaminant rules
Amendments to the Safe Drinking Water Act in 1996 require that the USEPA publish a list, known as the Drinking Water Contaminant Candidate List (CCL), of pollutants that aren’t currently regulated as part of the national primary drinking water regulations (NPDWR) but are known or anticipated to occur in public water systems (see www.epa.gov/OGWDW/ccl/cclfs.html). Beginning with 1998, a new CCL is required to be published every five years thereafter.
An initial broad list of more than 300 suspected contaminants was narrowed to a list of 60 priority contaminants. Each contaminant is divided into categories of need for regulatory determinations, research and occurrence. The USEPA will select at least five contaminants from the Regulatory Determination category and determine, by August 2001, if there’s a need for their regulation based on whether a meaningful opportunity is likely to reduce health risk. If deemed necessary, a regulation may not be promulgated until February 2005.
Clearly, many waterborne contaminants are a potential risk to human health that are not yet regulated or monitored. Unpredictable source water conditions, inconsistent treatment efficacy, compromised distribution systems and unrecognized contaminants all contribute to the need for consumers to take control of their drinking water quality. Regardless of your particular demographics, properly maintained POU devices can provide additional measures of safety to the water you consume.
- Moore, et al., “Waterborne disease in the United States, 1991 and 1992,” Journal of the American Water Works Association (AWWA), 86: p. 87-99, 1994.
- USEPA, “Environmental Goals for America, with Milestones for 2005, Policy Planning & Evaluation,” (2162) December 1996.
- USEPA, “Reducing risk: Setting priorities and strategies for environmental protection,” SAB-EC-90-021, Washington, D.C., USEPA, Science Advisory Board, 1990.
- USEPA, “Exposure factors handbook,” EPA/600/8-89/043, Washington, D.C., 1989.
- National Ground Water Association, “U.S. ground water industry market backgrounder,” NGWA, Westerville, Ohio, 1998.
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