1
Small Water Supply Systems: An Unsolved Problem

In the United States today, most citizens expect to have access to low-cost, high-quality drinking water at their taps. While the U.S. drinking water supply is superior to water supplies in many parts of the world and reflects the high priority that Americans have placed on water quality, there is still room for significant improvement in water service. For example, 23.5 percent of all U.S. community water systems violated Safe Drinking Water Act microbiological standards one or more times between October 1992 and January 1995, and 1.3 percent violated chemical standards, according to data from the U.S. Environmental Protection Agency (EPA). Waterborne disease outbreaks still occur in the United States, providing a reminder that contaminated drinking water continues to pose health risks even in highly developed nations.

Small communities face the greatest difficulty in supplying water of adequate quality and quantity because they have small customer bases and therefore often lack the revenues needed to hire experienced managers and to maintain and upgrade their water supply facilities. Interruptions in water service due to inadequate management, as well as violations of drinking water standards, are problems for some of these systems. Although the problems of supplying drinking water through individually operated small water systems have long been known, the number of small water systems has continued to increase.

As part of its long-term effort to improve water supply service to small communities, the EPA asked the National Research Council (NRC) to recommend strategies for improving water service to the nation's small communities. The EPA asked that, as part of its analysis, the NRC examine whether streamlining of current pilot testing requirements is possible for "package" water treatment



The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 12
--> 1 Small Water Supply Systems: An Unsolved Problem In the United States today, most citizens expect to have access to low-cost, high-quality drinking water at their taps. While the U.S. drinking water supply is superior to water supplies in many parts of the world and reflects the high priority that Americans have placed on water quality, there is still room for significant improvement in water service. For example, 23.5 percent of all U.S. community water systems violated Safe Drinking Water Act microbiological standards one or more times between October 1992 and January 1995, and 1.3 percent violated chemical standards, according to data from the U.S. Environmental Protection Agency (EPA). Waterborne disease outbreaks still occur in the United States, providing a reminder that contaminated drinking water continues to pose health risks even in highly developed nations. Small communities face the greatest difficulty in supplying water of adequate quality and quantity because they have small customer bases and therefore often lack the revenues needed to hire experienced managers and to maintain and upgrade their water supply facilities. Interruptions in water service due to inadequate management, as well as violations of drinking water standards, are problems for some of these systems. Although the problems of supplying drinking water through individually operated small water systems have long been known, the number of small water systems has continued to increase. As part of its long-term effort to improve water supply service to small communities, the EPA asked the National Research Council (NRC) to recommend strategies for improving water service to the nation's small communities. The EPA asked that, as part of its analysis, the NRC examine whether streamlining of current pilot testing requirements is possible for "package" water treatment

OCR for page 12
--> plants (off-the-shelf units like small versions of the custom-designed water treatment equipment used by larger utilities). This report addresses the EPA's request. It was prepared by the NRC's Committee on Small Water Supply Systems, appointed in 1994 in response to the EPA's request. The committee consisted of 12 experts in water treatment engineering, utility management and financing, environmental law, and public health. Members convened six times over an 18-month period to develop this report. The group received input from a wide range of stakeholders—including utility personnel, equipment manufacturers, state regulators, rural assistance program managers, and environmentalists—who are concerned about water supply service to small communities. This chapter outlines the scope of the small systems problem and documents that although long known, the problems of small water systems have not been solved. Chapter 2 describes the status of small community water systems and the problems faced by consumers when these systems are unable to maintain adequate facilities. Chapters 3 and 4 respond to the EPA's request for guidance on testing package water treatment systems: Chapter 3 reviews the capabilities of various classes of technologies appropriate for small systems, and Chapter 4 advises on the degree to which testing of these technologies can be standardized. Chapter 5 reviews institutional options (including restructuring system management and developing sound financial plans) for improving water supply service to small communities. Chapter 6 recommends ways to improve the training of small water system operators. Increasing Number of Small Systems For the purposes of this report, a public water system is considered small if it serves 10,000 or fewer people, although systems serving fewer than 500 people face the biggest challenges in providing adequate water service. The EPA divides public water systems into three categories: community water systems, which serve the same population all year; nontransient noncommunity water systems such as schools, factories, and hospitals with their own water supplies; and transient noncommunity water systems such as campgrounds, motels, and gas stations with their own water supplies (see Box 1-1 for the formal definitions). This report generally focuses on community water systems because the problems of serving an entire community are different from those associated with developing a water system for a single building or installation. For example, while community water systems must raise capital for improvements by issuing bonds, applying for grants or loans, or increasing their water rates, noncommunity systems typically finance improvements internally, through their overall budget for capital improvements (Task Force on Drinking Water Construction Funding and Regionalization, 1991). Nevertheless, much of the information in the report is also relevant to noncommunity water systems. As shown in Table 1-1, the number of small community water systems has

OCR for page 12
--> BOX 1-1 Classes of U.S. Public Water Supply Systems According to the EPA (1994), there are more than 190,000 public water systems in the United States (including those in U.S. territories and Native American lands). The EPA classifies any water distribution system as public if it supplies at least 15 service connections or at least 25 people for at least 60 days each year. The agency divides these public water systems into three categories: Community water systems provide drinking water to the same population all year. According to the EPA (1994), the 57,561 community systems in the United States as of 1993 served nearly 243 million people. (The remaining 15 million U.S. residents obtained their water from private wells or other systems serving fewer than 15 connections or 25 people.) Nontransient noncommunity water systems provide drinking water to at least 25 of the same people for at least 6 months each year. Schools, factories, and hospitals with their own water supplies are examples of such systems. The EPA (1994) estimated that as of 1993, 23,992 such systems served more than 6 million people. Transient noncommunity water systems provide drinking water to transitory populations in nonresidential areas. Examples are campgrounds, motels, and gas stations that have their own water supplies. According to the EPA (1994), 109,714 such systems existed by 1993 and served more than 15 million people. increased substantially in the United States in the last three decades. For example, in 1963 there were approximately 16,700 water systems serving communities with populations of fewer than 10,000; by 1993 this number had more than tripled—to 54,200 such systems. Approximately 1,000 new small community water systems are formed each year (EPA, 1995). The fragmented U.S. network for supplying drinking water contrasts significantly with water supply networks in many other parts of the developed world. In England and Wales, for example, 10 regional water organizations and 22 water companies provide water and sewerage service to 99 percent of the population of 50 million (Okun, 1977). The regional water agencies were the result of a national program initiated during World War II to streamline the allocation of water resources, in part to ensure that water supplies would be adequate for fighting fires caused by German bomb attacks. The program initially resulted in a reduction from 1,200 water systems serving 40 million people in 1945 to fewer than 200 systems serving 50 million people in 1972. The success of this program led to a much larger regionalization program in 1973, resulting in the creation of the 10 public water authorities, which were privatized in 1989. The initial consolidation of water systems was achieved by encouraging large cities to extend service to outlying small communities or, in areas with no large cities, by encouraging small communities to form regional water boards. In addition to water

OCR for page 12
--> TABLE 1-1 U.S. Community Water Systems: Size Distribution and Population Served   Number of Community Systems Serving This Size Communitya Total Number of U.S. Residents Served by Systems This Sizeb> Population Served 1963 1993 1963 1993 Under 500 5,433 (28%) 35,598 (62%) 1,725,000 (1%) 5,534,000 (2%) 501-10,000 11,308 (59%) 18,573 (32%) 27,322,000 (18%) 44,579,000 (19%) More than 10,000 2,495 (13%) 3,390 (6%) 121,555,000 (81%) 192,566,000 (79%) Total 19,236 57,561 150,602,000 242,679,000 a Percentage indicates the fraction of total U.S. community water supply systems in this category. b Percentage is relative to the total population served by community water systems, which is less than the size of the U.S. population as a whole. SOURCES: EPA, 1994; Public Health Service, 1965. supply, the original authorities provided sewerage, wastewater treatment, storm water and flood control, and many other water-related services. The comparative fragmentation of the U.S. water supply industry—and the resulting large number of water systems serving small populations—reflects the historical development pattern of the industry in the United States. Historically, each U.S. town and city developed its own local supply, subject initially to local and later to state and federal oversight. As shown in Table 1-2, ownership of small water systems was and still is fragmented among city, county, state, and federal government bodies and private utilities. The type of consolidation that occurred in England and Wales after World War II has never occurred in the United States. Increasing Number of Water Supply Regulations As shown in Figure 1-1, the number of drinking water contaminants regulated by the federal government has increased dramatically in the past decade, increasing the complexity for both small and large systems of providing water that meets all applicable regulations. U.S. public health officials developed the first drinking water standards in 1914, but until 1974 these standards could be legally enforced only for water transported between two or more states. The

OCR for page 12
--> TABLE 1-2 Ownership of U.S. Community Water Systems   Ownership (As Percentage of Total Systems in Size Category)   Public Private Population Served City/ Municipality County/Water District State Federal Total Public   Under 500 18% 7% 2% 1% 28% 72% 501-3,300 56% 17% 3% 1% 77% 23% More than 3,300 71% 18% 2% 4% 95% 5% Total 36% 11% 3% 1% 51% 49%   SOURCE: EPA, 1990b. 1914 standard was issued under the auspices of the Interstate Quarantine Act of 1893, which was designed to prevent the spread of communicable diseases from state to state. It initially covered only coliform bacteria, which indicate the possible contamination of water with fecal matter and thus the possible presence of disease-causing organisms (AWWA, 1990). The U.S. Public Health Service revised the standard and added new contaminants to it in 1925, 1942, 1946, and 1962. Although many states adopted the guidelines for community water supplies in their jurisdictions, the standards were federally enforceable only for municipalities whose water was used on interstate carriers such as buses, trains, airplanes, and ships (AWWA, 1990). In 1969, a major survey of community water supplies showed that few water purveyors monitored the quality of their water to determine whether it met the recommended U.S. Public Health Service standards. Three years later, studies revealed the presence of trace quantities of contaminants in the lower Mississippi River, the source of drinking water for New Orleans (EPA, 1976). Public concern about these issues and environmental contamination in general led Congress to pass the Safe Drinking Water Act (SDWA) in 1974. The act requires that all public water supplies meet national ''maximum contaminant levels" (MCLs). The EPA is responsible for developing drinking water standards under the act; the initial MCLs were based on the U.S. Public Health Service guidelines and a review of health risks of potential drinking water contaminants by the NRC (1977). An EPA survey conducted in 1981 and 1982 of 1,000 public water systems using ground water revealed the presence of trace concentrations of volatile

OCR for page 12
--> FIGURE 1-1 Number of drinking water contaminants regulated by the U.S. government. The large increase in regulated contaminants that begins after 1976 is due to regulations issued under the Safe Drinking Water Act and its amendments. SOURCE: Reprinted, with permission, from Okun (1996). ©1996 by the American Society of Civil Engineers. organic chemicals in approximately one-quarter of the systems (AWWA, 1990). The survey results led to concern that the existing SDWA standards were insufficient to protect public health from synthetic organic chemicals in drinking water (Congressional Research Service, 1993). As a result, Congress strengthened the SDWA with a series of amendments in 1986. The amendments required the EPA to develop MCLs for 83 contaminants and, beginning in 1991, to regulate 25 additional contaminants every 3 years—thus the large increase in regulated contaminants shown in Figure 1-1. New contaminants to be regulated included a variety of volatile organic chemicals, inorganic chemicals, viruses, and parasites.

OCR for page 12
--> The amendments further mandated that the EPA develop rules governing which types of water supplies must provide disinfection as a minimum level of treatment and which ones must also provide filtration. Table 1-3 lists contaminants regulated by the SDWA and its amendments as of 1996. Compliance with this large number of water quality regulations can stretch the resources of the state agencies responsible for monitoring the performance of water purveyors or behalf of the federal government. In July 1996, Congress again amended the SDWA. The amendments removed the requirement for EPA to regulate 25 new contaminants every 3 years. Instead the EPA is to regulate contaminants based on adverse health effects, occurrence, and the level of risk posed by the contaminant. In addition, the amendments established for the first time a state revolving fund to help pay for improvements to water service. Nonetheless, the states still face a major challenge in implementing the existing SDWA regulations and in determining how to respond to changes that will result from the 1996 amendments. Increasing Responsibilities for Local and State Governments When Congress passed the SDWA, legislators recognized that small communities might not be able to afford the technologies needed for compliance. For example, the House of Representatives, in its summary report describing the key elements of the act, noted, "It is evident that what is a reasonable cost for a large metropolitan (or regional) public water system may not be reasonable for a small system which serves relatively few users" (Congressional Research Service, 1982). Legislators believed that the problems of small systems would self-correct. They assumed that because small communities would be unable to afford the new technologies needed to meet the regulations, small water systems would consolidate with other systems to provide a larger customer base. The House, in its legislative summary, anticipated development of "a regional water system which can afford to purchase and use [water treatment] methods, to seek additional sources of funding such as state aid, or to develop a plan for otherwise serving the affected population after any existing inadequate system is closed" (Congressional Research Service, 1982). As indicated by the still-increasing number of small systems, this anticipated regionalization has not occurred. Instead, violations of the drinking water standards, especially the microbiological standards, have become common. For example, 29.5 percent of systems serving fewer than 500 people violated microbiological standards one or more times between October 1992 and January 1995 (see Chapter 2). Further, in implementing the SDWA, the EPA has recognized that it is not always feasible to hold small communities to the same compliance schedules, standards, and monitoring requirements as larger communities. For example, systems serving fewer than 10,000 people are not currently required to

OCR for page 12
--> meet the MCL for trihalomethanes (THMs), created when chlorine used for disinfection reacts with naturally occurring or other organic matter in the water (EPA, 1990a).1 In addition, systems serving 3,300 or fewer people were given 2 extra years to complete needed treatment installations for lead contamination. For a variety of contaminants, EPA allows up to five small systems to pool their water samples and have them tested as a composite in the laboratory, rather than requiring that each system test its water individually. Finally, exemptions from water quality standards are available to systems that cannot meet the standards due to severe economic constraints. Such exemptions may be granted for an unlimited number of 3-year periods for systems with 500 or fewer service connections. Although the drinking water standards are federally mandated, the states (with the exception of Wyoming2) are responsible for enforcing them, and inadequate enforcement capability may have contributed to the large number of violations of the drinking water standards and the lack of consolidation of water systems. Staffing levels of state drinking water programs have traditionally been constrained, and they are becoming even more stretched with the promulgation of new federal regulations. In a 1992 resource needs survey, the Association of State Drinking Water Administrators (ASDWA) determined that, in total, state agencies had 2,272 staff years of resources available each year to implement the safe drinking water program but that they would need 4,958 staff years of effort in 1993 to implement the expanding array of federal drinking water regulations (ASDWA, personal communication, 1995). A state program field staff person could be responsible for monitoring the operational performance and regulatory compliance of between 150 and 250 public water systems. Assuming an equal distribution of the approximately 190,000 public water systems in the country, the average field person would be responsible for overseeing the water supply systems of more than 165 communities, both large and small. Funding for implementation of state drinking water programs historically has been limited (and is the reason for the shortage of personnel). A 1988 study conducted by ASDWA revealed that state drinking water programs were experiencing a $41 million budget shortfall (ASDWA and EPA, 1989). In 1993, the U.S. General Accounting Office (GAO) concluded that "Severe resource constraints have made it increasingly difficult for many states to effectively carry out the monitoring, enforcement, and other mandatory elements of EPA's drinking water program.…The situation promises to deteriorate further" (GAO, 1993). 1   Small systems may be required to meet THM standards in the future if the EPA implements a proposed rule governing disinfection and disinfection byproducts. Under this proposed rule, small systems would have to meet the THM standards but would not have to monitor for THMs as frequently as larger systems. 2   All states except Wyoming have assumed primacy to enforce the SDWA (GAO, 1994).

OCR for page 12
--> TABLE 1-3 Contaminants Regulated Under the Safe Drinking Water Act Individually regulated contaminants Phase II contaminants Phase V contaminants Arsenic Acrylamidea Antimony Coppera Alachlor (Lasso) Beryllium Fluoride Asbestos Cyanide Leada Atrazine Dalapon Total coliforms Barium Di(2-ethylhexyl)adipate Total trihalomethanes (TTHM)b Carbofuran Di(2-ethylhexyl)phthalate   Cadmium Dichloromethane Phase I contaminants Chlordane Dinoseb Benzene Chromium Dioxin (2,3,7,8-TCDD) Carbon tetrachloride Dibromochloropropane (DBCP) Diquat 1,2-Dichloroethane o-Dichlorobenzene Endothall 1,1-Dichloroethylene cis-1,2-Dichloroethylene Endrin p-Dichlorobenzene trans-1,2-Dichloroethylene Glyphosate 1,1,1-Trichloroethane 1,2-Dichloropropane Hexachlorobenzene (HCB) Trichloroethylene 2,4-D Hexachlorocyclopentadene Vinyl chloride 2,4,5-TP (Silvex) Nickel   Ethylbenzene Oxamyl (vydate) Surface water treatment Ethylene dibromide (EDB) Polycyclic aromatic hydrocarbons (benzo(a)pyrene) Giardia lambliaa Epichlorohydrina   Legionellaa Heptachlor Picloram Heterotrophic plate counta Heptachlor epoxide Simazine Turbiditya Lindane (BHC-gamma) Thallium Virusesa Mercury 1,2,4-Trichlorobenzene   Methoxychlor 1,1,2-Trichloroethane   Monochlorobenzene

OCR for page 12
--> Nitrate Radionuclides Nitrite Beta particle and photon radioactivityb Polychlorinated biphenyls Gross alpha particle activity   Radium-226 Pentachlorophenol Radium-228 Selenium   Styrene   Tetrachloroethylene   Toluene   Toxaphane   Xylenes (total)   NOTE: The phases in the table indicate the different stages in which the EPA issued regulations for these contaminants under the Safe Drinking Water Act and its amendments. The EPA issued regulations for phase I contaminants in 1987, for phase II contaminants in 1991, and for phase V contaminants in 1992. Regulations for surface water treatment were issued in 1989. Radionuclide regulations were issued in 1993. a These contaminants are regulated by a treatment technique instead of an MCL. b Regulations for these contaminants are not applicable to small systems. SOURCE: EPA, 1994.

OCR for page 12
--> More recently, the EPA estimated that states would require $311 million in 1995 to implement the SDWA (Leiby, 1995). However, during 1995 the federal appropriation to states for the SDWA was $70 million, and state revenues for implementing the act totaled $126 million, leaving the states with a $115 million shortfall (Leiby, 1995; National Conference of State Legislatures, 1995). It is as yet unclear how the 1996 SDWA amendments will affect state staffing and resource requirements. In summary, the problems of small water supply systems, while long recognized, have not been solved. The number of small systems has increased over the past three decades, despite legislation to improve water service. Ensuring that small systems are complying with the complex array of drinking water regulations is a major task for state and local governments. Addressing the small systems problem will require consideration of technical, financial, and institutional options, as discussed in this report. References AWWA (American Water Works Association). 1990. Water Quality and Treatment: A Handbook of Community Water Supplies, Fourth Edition. New York: McGraw-Hill, Inc. ASDWA (Association of State Drinking Water Administrators) and EPA (Environmental Protection Agency). 1989. State Costs of Implementing the 1986 Safe Drinking Water Act Amendments: Results and Implications of the 1988 Association of State Drinking Water Administrators Survey of State Primacy Program Resource Needs. Washington, D.C.: ASDWA. Congressional Research Service. 1982. A Legislative History of the Safe Drinking Water Act. Serial No. 97-9. Washington, D.C.: Library of Congress, Congressional Research Service, Environmental and Natural Resources Policy Division. Congressional Research Service. 1993. A Legislative History of the Safe Drinking Water Act Amendments 1983–1992. Washington, D.C.: Library of Congress, Congressional Research Service, Environment and Natural Resources Policy Division. EPA. 1976. Industrial Pollution of the Lower Mississippi River in Louisiana. Dallas: EPA Region VI. EPA. 1990a. Environmental Pollution Control Alternatives: Drinking Water Treatment for Small Communities. EPA/625/5-90/025. Cincinnati: EPA, Risk Reduction Engineering Laboratory. EPA. 1990b. Improving the Viability of Existing Small Drinking Water Systems. EPA 570/9-90-004. Washington, D.C.: EPA, Office of Water. EPA. 1994. The National Public Water System Supervision Program: FY 1993 Compliance Report. EPA 812-R-94-001. Washington, D.C.: EPA, Office of Water. EPA. 1995. Unpublished data from the Safe Drinking Water Information System. Washington, D.C.: EPA. GAO (General Accounting Office). 1993. Drinking Water Program: States Face Increased Difficulties in Meeting Basic Requirements. Washington, D.C.: U.S. General Accounting Office. GAO. 1994. Drinking Water: Stronger Efforts Essential for Small Communities to Comply with Standards. Washington, D.C.: U.S. General Accounting Office. Leiby, V. 1995. Testimony to the Senate Appropriations Subcommittee on VA, HUD, and Independent Agencies in Regard to FY 1996 Appropriations for the PWSS Program on Behalf of the Association of State Drinking Water Administrators. Washington, D.C.: ASDWA. National Conference of State Legislatures. 1995. Alternative Funding Mechanisms for State Drinking Water Programs, 1994–1995. Denver: National Conference of State Legislatures.

OCR for page 12
--> National Research Council. 1977. Drinking Water and Health. Washington, D.C.: National Academy Press. Okun, D. A. 1977. Regionalization of Water Management: A Revolution in England and Wales. London: Applied Science Publishers. Okun, D. A. 1996. From cholera to cancer to cryptosporidiosis. Journal of the Environmental Engineering Division, American Society of Civil Engineers 122(6):453–458. Public Health Service. 1965. Statistical Summary of Municipal Water Facilities in the United States, January 1, 1963. Public Health Service Publication No. 1039. Washington, D.C.: Public Health Service. Task Force on Drinking Water Construction Funding and Regionalization. 1991. Safety on Tap: A Strategy for Providing Safe, Dependable Drinking Water in the 1990s. Portland: Oregon Health Division, Drinking Water Section .