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Watershed Management for Potable Water Supply: Assessing the New York City Strategy (2000)

Chapter: 3 Evolution of Key Environmental Laws, Regulations, and Policies

« Previous: 2 The New York City Water Supply System
Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

3
Evolution of Key Environmental Laws, Regulations, and Policies

The Watershed Rules and Regulations of the New York City Memorandum of Agreement (MOA) are among the most comprehensive and detailed regulations regarding watershed activities found in this country. However, they cannot be considered in isolation given the large number of federal, state, and local statutes and regulations with which New York City must comply. This chapter briefly describes the initial impetus for the creation of environmental regulations relating to drinking water, it outlines certain federal regulations that pertain to the New York City drinking water supply, and it describes how the MOA attempts to fill gaps between federal, state, and local environmental regulations.

GLOBAL PUBLIC CONCERNS ABOUT DRINKING WATER SAFETY

Although environmental regulations have not traditionally focused on the watershed as a management unit, this approach has become more common in the last ten years (NRC, 1999). Watershed approaches to water resource management require the integration of traditional water quality concerns (such as the safety of drinking water) with more general ecological and aesthetic concerns (such as the health of aquatic ecosystems). For watershed protection programs to succeed, a multitude of interests, stakeholders, and priorities must be considered, creating daunting and relatively new challenges for water supply managers and environmental regulators. Some stakeholders are most concerned with waterborne diseases, others with the chronic effects of chemicals used in water treatment, and others with ecological and aesthetic considerations.

In addition to multiple stakeholder concerns, water supply managers and environmental regulators must also contend with increased public awareness

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

regarding water safety. The emergence of the media has had a powerful effect on public perceptions of environmental quality, including water quality. A 1993 nationwide study of consumer attitudes about water quality conducted by the American Water Works Association (AWWA, 1993) found that about 40 percent of all persons interviewed nationwide had ''seen or heard something [in the media] that made them worry about their local water quality," although fewer (26 percent) were aware of a local threat or incident. Although there have been few documented cases of contaminated water adversely affecting public health, the public's perception of water safety varies greatly. This variability is evident in Box 3-1, which describes the results of a survey conducted in New York City in which residents were questioned about their drinking water. Consumer confidence in the water supply is a complex issue that must be taken into consideration in making management decisions.

The most prominent public concerns regarding drinking water quality and water supply systems are discussed below, followed by a description of the relevant environmental laws and regulations that have been developed to address these concerns. These regulations are not only relevant to public health and safety and to aesthetic improvements in water supply reservoirs, but they are also economically prudent for society over the long term.

Waterborne Infectious Disease

As with most other environmental issues, the greatest public concern regarding drinking water is that it can potentially endanger human health and safety (Freudenberg and Steinsapir, 1992; Szasz, 1994). Waterborne infectious diseases are the most recognized type of danger because numerous microbial agents transmitted by ingestion of contaminated water have the potential to cause acute or chronic illness.

Disease outcomes associated with waterborne infections include mild to lifethreatening gastroenteritis, hepatitis, conjunctivitis, respiratory infections, and generalized infections. Most disease-causing microorganisms (pathogens) originate in the enteric tracts of humans or animals and enter water sources via fecal contamination from human or animal sources. However, there are some indigenous aquatic microorganisms that are also capable of causing disease under certain circumstances. Although most waterborne pathogens must infect and reproduce within a human host in order to be considered virulent, there are waterborne microorganisms that affect humans through the production of toxins. The outcomes of exposure to pathogenic organisms can be highly variable. Some waterborne pathogens will cause disease in healthy exposed persons, while others pose little or no threat to healthy adults but can pose a threat to children, the elderly, or anyone with a weakened immune system.

The connection between drinking water quality and human health has been recognized since ancient times, as evidenced by the development of technologies

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

BOX 3-1
Public Perception of Drinking Water Safety in New York City

This box discusses a recent study on public perception of drinking water quality in New York City and compares the results to trends observed nationwide. Public perception of drinking water safety is an important indicator of the success of public utilities, although it is not as objective as water quality monitoring data. Water suppliers and the public often have very different impressions of drinking water safety. For example, a nationwide study of multiple stakeholders concluded, "Most public officials, water utility managers, and environmentalists believe the greatest threat to the quality of drinking water today is problems with water quality at the source. But the public is just as likely to perceive that problems with [water] treatment methods pose the greatest threat" (AWWA, 1993). In addition, two-thirds of American adults believe that they receive very little or no information about water quality, while 151 water utility managers nationwide overestimated the amount of information the public perceives it is getting about the quality of its drinking water (AWWA, 1993).

Survey of Water Consumers. Because New York City's water is unfiltered, it has garnered increased attention compared to other communities. In a recent consumer survey of 1,560 randomly selected City residents (Pfeffer and Stycos, 1996), respondents were asked whether they agreed or disagreed with the following statement: "New York City has one of the safest and cleanest water supplies in the world." 54 percent of respondents agreed, while 46 percent disagreed. This indicator of confidence in the water supply reveals clear differences between City residents' perceptions of the overall quality of the water supply and the favorable compliance record of the NYC DEP (discussed in detail in Chapter 5).

Reasons for Lacking Confidence in Tap Water. To help determine why a substantial proportion of New York City's population lacks confidence in the water supply, survey respondents were asked more specific questions about their perception of tap water quality, their satisfaction with federal drinking water standards, whether they drink bottled water and why, whether they have had problems with tap water in the past, and other issues. Results of the survey are given in Table 3-1.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

as poor, while 87.1 percent of those who are confident in the water supply rate the water as good or excellent.

Differences in confidence in the water supply are also related to trust in the NYC DEP. Sixty (60) percent of those confident in the water supply give NYC DEP an overall job rating of good or excellent, while just one-third of those survey respondents who lack confidence in the water supply gave NYC DEP such high marks. Those who lack confidence are also much more likely to think that federal water quality standards are "not strict enough," whereas those confident in the system are more likely to think the guidelines are "about right."

Differences in levels of confidence in the water supply are also reflected in water consumption. Those lacking confidence are twice as likely to drink bottled water only. Only 31 percent of all New Yorkers drink tap water exclusively (482 out of 1560), a rate that is significantly lower than the rates in other parts of the country (AWWA, 1993). About 30 percent of New Yorkers say they drink bottled water for the taste; however, more than half report that they drink it for health reasons (data not shown).

The strongest predictor of confidence in the water supply were past problems with tap water taste, color, and clarity. Those New Yorkers who experienced problems with the taste of tap water were almost twice as likely to lack confidence in New York City water. Finally, differences in confidence in the water supply relate, to a lesser degree, to one's environmental awareness, income, education, sex, race, and place of residence. In general, the observed public perceptions of drinking water quality in New York City are typical of nationwide patterns reported by the AWWA (1993).

TABLE 3-1 Selected Factors Related to Public Confidence in New York City's Water Supply

 

Total number responding

NYC's Water is Safe and Clean

Percent Agree

Percent Disagree

All respondents

1,560

54.0

46.0

Perception of overall tap water quality:

Poor

465

12.3

50.3

Good

853

62.0

46.0

Excellent

234

25.1

3.1

Trust in DEP-provided information:

No Trust

183

9.0

14.9

Some Trust

1,167

75.6

73.9

Complete Trust

197

14.4

10.6

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

 

Total number responding

NYC's Water is Safe and Clean

Percent Agree

Percent Disagree

Overall DEP job rating:

Poor

153

4.9

15.6

Fair

608

31.7

47.6

Good

661

50.9

32.4

Excellent

90

9.5

1.4

Federal drinking water quality standards:

Too strict

35

2.0

2.5

About right

601

50.4

24.5

Not strict enough

869

43.3

70.3

Water Consumption:

Tap only

483

31.9

21.3

Bottled only

280

10.7

26.5

Tap and bottled

760

48.2

49.4

Problems with Tap Water

Taste

723

36.8

63.2

Color/clarity

940

45.3

54.7

Were Aware of

NYC DEP

1,452

54.0

46.0

NYC watershed

1,047

56.9

43.1

MOA

614

61.4

38.6

Cryptosporidium

309

52.8

47.2

Total Annual Household Income

<$35,000

633

49.0

51.0

$35-70,000

485

52.8

47.2

>$70,000

225

68.4

31.6

Education

Less than high school

151

53.6

46.4

High school

404

49.8

50.2

Post secondary

982

55.6

44.4

Borough of Residence

Brooklyn

487

50.5

49.5

Bronx

487

54.2

45.8

Manhattan

308

56.5

43.5

Queens

411

54.7

45.3

Staten Island

80

61.3

38.8

 

Source: Pfeffer and Stycos (1996). Data were collected in New York City's five boroughs in Spring 1996 via telephone interviews of individuals living in households selected by means of random digit dialing. Individuals answering the call were asked for the person in their household age 18 or older who last had a birthday. That person was then interviewed, for an average time of 20 minutes. The interviews covered a wide range of topics including the subject's evaluation of world, national, and local environments, specific environmental concerns (especially those related to water quality), attitudes toward environmental problems, knowledge of environmental law, population, and environmental behavior, and their sociodemographic characteristics.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

to treat contaminated water. Baker (1949) reports that descriptions of water treatment are found in Sanskrit medical lore and Egyptian inscriptions dating back to the fifteenth century B.C. Boiling water and filtration through porous vessels or through sand and gravel have been used to improve water quality for thousands of years. The writings of Hippocrates (460–354 B.C.) discuss the relationship between water quality and health and recommend boiling rain water and straining it through a cloth bag (NRC, 1977).

In the nineteenth and twentieth centuries, installation of filtration and disinfection processes in community water supplies has been associated with decreased morbidity and mortality from infectious diseases in the United States and Europe. Filtration was first used to remove particles from drinking water in New York State during the 1870s. Later experiments demonstrated that filtration had a direct impact on observed disease rates of typhoid fever. Disinfection of drinking water supplies, developed around the turn of the century, has virtually eliminated many waterborne microbial diseases in developed countries. Chlorine was and continues to be the most popular disinfectant because of its relatively low cost and high potency. Like other disinfectants, chlorine inactivates bacteria, viruses, and other microbes via nonspecific oxidation of the organism. Table 3-2 lists landmark advances in the discovery and control of waterborne infectious disease.

Common Waterborne Pathogens

The most commonly recognized waterborne pathogens consist of several groups of enteric and aquatic bacteria, enteric viruses, and enteric protozoa (Table 3-3). Data collected on waterborne disease outbreaks from 1920 to the present indicate that there has been a shift in the microorganisms responsible for waterborne disease. Recognized outbreaks during the first half of the twentieth century were caused by bacterial agents—primarily Salmonella typhi and shigella sp. Since the 1970s, recognized waterborne disease outbreaks have been caused predominantly by enteric protozoa such as Giardia or Cryptosporidium (when an etiologic agent is identified) or viral agents (Craun, 1986). This shift may be due to the greater resistance of protozoa to chlorination, which is shown in Table 3-4.

Table 3-3 lists only those organisms documented to have caused waterborne disease. Other pathogens that can be transmitted via ingestion of water include adenoviruses, Helicobacter pylori, atypical (nontuberculosis) mycobacteria, and Microsporidia (Enterocytozoon and Septata).

Treatment Options for Controlling Waterborne Pathogens

Most waterborne pathogens are removed or inactivated by conventional water treatment processes such as coagulation and sedimentation, filtration, and disinfection. Enteric viruses and bacteria are particularly susceptible to disinfection

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

TABLE 3-2 Advances in the Recognition and Control of Waterborne Disease

Year

Event

1829

First well-documented water filter built by James Simpson for the Chelsea Water Company of London.

1849

An estimated 110,000 people die from cholera in the UK.

1854

John Snow removes the handle from the Broad Street pump in an effort to stop the transmission of cholera in London.

1872–1874

First water filtration plants in the U.S. built in Poughkeepsie, NY, and Hudson, NY.

1884

Robert Koch identifies Vibrio cholera as the causal agent of cholera and describes the germ theory of disease.

1887

Experiments on water filtration conducted in Lawrence, MA. This leads to the first rapid sand filter in 1893 and an observed 79 percent decrease in typhoid fever mortality over the next 5 years.

1892

Rienecke observes that increases in the bacterial content of drinking water in Hamburg, Germany, corresponded to increases in infant mortality and report a 50 percent decline in infant mortality from diarrheal disease in the year after Hamburg started to filter the public water supply.

1893

Chlorination used to treat sewage effluent in Brewster, NY, to protect New York City drinking water.

1897

Chlorination of drinking water in Maidstone, Kent, UK, after an outbreak of typhoid fever.

1902

First continuous chlorination of a water supply in Belgium.

1904

10 percent of U.S. urban population receives filtered water.

1907

46 U.S. cities using filtration to treat drinking water.

1908

First continuous, large-scale use of chlorination for an urban water supply in the U.S. in Jersey City, NJ.

1914

36 percent of U.S. urban population receives filtered water. Allan Hazen writes enthusiastically about the benefits of water chlorination.

1920

Earliest data on occurrence and causes of waterborne disease outbreaks in the U.S. is collected.

1930

27 percent of community water supplies in the U.S. have disinfection facilities.

1920–1935

Typhoid fever is the most commonly recognized waterborne disease in the U.S.

1936–1961

Shigellosis is the most commonly recognized waterborne disease in the U.S.

1965

Outbreak (16,000 cases) of waterborne salmonellosis in Riverside, CA. First documented waterborne outbreak of giardiasis in the U.S. occurs at Aspen, CO.

1971–1980

Giardiasis becomes the most commonly recognized waterborne disease.

1975

First recognized outbreak of waterborne disease caused by toxigenic E. coli in Crater Lake National Park, OR.

1984

First recorded waterborne outbreak of cryptosporidiosis occurs in Texas.

1989

First recorded waterborne outbreak of E. coli O157:H7 occurs in Missouri (243 cases, 4 deaths).

1993

Largest recorded waterborne disease outbreak in U.S. history caused by Cryptosporidium in Milwaukee, WI (estimated 400,000 cases).

 

Sources: Craun (1986), Hunter (1997), ILSI (1993), Long mate (1966), NRC (1977), Sedgwick and MacNutt (1910).

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

TABLE 3-3 Illnesses Caused by Microbial Agents Acquired by Ingestion of Water

Agent

Source

Incubation Period

Clinical Syndrome

Duration

Viruses:

Astrovirus

human feces1

1-4 days

Acute gastroenteritis

2-3 days; occasionally 1-14 days

Enteroviruses (polioviruses, coxsackieviruses, echoviruses)

human feces

3-14 days (usually 5–10 days)

Febrile illness, respiratory illness, meningitis, herpangina, pleurodynia, conjunctivitis, myocardiopathy, diarrhea, paralytic disease, encephalitis, ataxia

Variable

Hepatitis A

human feces

15-50 days (usually 25-30 days)

Fever, malaise, jaundice, abdominal pain, anorexia, nausea

1-2 weeks to several months

Hepatitis E2

human feces

15-65 days (usually 35-40 days)

Fever, malaise, jaundice, abdominal pain, anorexia, nausea

1-2 weeks to several months

Norwalk-like viruses

human feces

1-2 days

Acute gastroenteritis with predominant nausea and vomiting

1-3 days

Group A rotavirus

human feces1

1-3 days

Acute gastroenteritis with predominant nausea and vomiting

5-7 days

Group B rotavirus2

human feces1

2-3 days

Acute gastroenteritis

 

Bacteria:

Aeromonas hydrophila

fresh water

 

Watery diarrhea

Average 42 days

Campylobacter jejuni

human and animal feces

3-5 days (1-7 days)

Acute gastroenteritis, possible bloody and mucoid feces

1-4 days occasionally > 10 days

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

Agent

Source

Incubation Period

Clinical Syndrome

Duration

Enterohemorrhagic E. coli O157:H7

human and cattle feces

3-5 days

Watery, then grossly bloody diarrhea, vomiting, possible hemolytic uremic syndrome

1-12 days Average 7-10 days

Enteroinvasive E. coli

human feces

2-3 days

Possible dysentery with fever

1-2 weeks

Enteropathogenic E. coli

 

2-6 days

Watery to profuse watery diarrhea

1-3 weeks

Enterotoxigenic E. coli

human feces?

12-72 hours

Watery to profuse watery diarrhea

3-5 days

Plesiomonas shigelloides

fresh surface water, fish, crustaceans, animals

1-2 days

Bloody and mucoid diarrhea, abdominal pain, nausea, vomiting

11 days average

Salmonellae

human and animal feces

8-48 hours

Loose, watery, occasionally bloody diarrhea

3-5 days

Salmonella typhi2

human feces and urine

7-28 days (average 14 days)

Fever, malaise, headache, cough, nausea, vomiting, abdominal pain

Weeks to months

Shigellae

human feces

1-7 days

Possible dysentery with fever

4-7 days

Vibrio cholera O12

human feces

9-72 hours

Profuse, watery diarrhea, vomiting, rapid dehydration

3-4 days

Vibrio cholera non-O12

human feces

1-5 days

Watery diarrhea

3-4 days

Yersinia enterocolitica

animal feces and urine

2-7 days

Abdominal pain, mucoid, occasionally bloody diarrhea, fever

1-21 days average 9 days

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

Agent

Source

Incubation Period

Clinical Syndrome

Duration

Protozoa:

Balantidium coli2

human and animal feces

Unknown

Abdominal pain, occasional mucoid or bloody diarrhea

Unknown

Cryptosporidium parvum

human and animal feces

1-2 weeks

Profuse, watery diarrhea

4-21 days

Entamoeba histolytica2

human feces

2-4 weeks

Abdominal pain, occasional mucoid or bloody diarrhea

Weeks to months

Cyclospora cayetenensis2

human feces

1 week average

Watery diarrhea, profound fatigue, anorexia, weight loss, bloating, abdominal cramps, nausea

Weeks if untreated

Giardia lamblia

human and animal feces

5-25 days

Abdominal pain, bloating, flatulence, loose, pale, greasy stools

1-2 weeks to months and years

Algae:

Cyanobacteria (Anabaena spp., Aphanizomenon spp., Microcystis spp.)2

Algal blooms in water

A few hours

Toxin poisoning (blistering of mouth, gastroenteritis, pneumonia)

Variable

Helminths:

Dracunculus medinensis2 (Guinea worm)

larvae

8-14 months (usually 12 months)

Blister, localized arthritis of joints adjacent to site of infection

Months

1 Animal strains of these viruses are not believed to be pathogenic for humans.

2 Waterborne infections in the U.S. are rare or undocumented.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

TABLE 3-4 Chlorine Disinfection Requirements for 99 Percent Inactivation of Waterborne Pathogens

Organism

Temperature (°C)

pH

Chlorine (mg/L)

CT Valuea

Escherichia coli

5

6.5

0.02–0.10

0.02

 

23

7.0

0.10

0.014

Giardia lamblia

5

7.0

2.0–8.0

25.5–44.8

 

25

7.0

1.5

<15

Cryptosporidium parvum

25

7.0

80

7,200

a CT = concentration of chlorine (mg/L) times the contact time (minutes)

Adapted from Sterling (1990).

by chlorine and ozone. Enteric protozoa, on the other hand, are relatively resistant to chlorine disinfection but are typically removed by the physical processes of coagulation and flocculation followed by filtration. Unfortunately, these treatment processes do not guarantee complete removal of microbial pathogens from drinking water, as evidenced by outbreaks of waterborne disease associated with water supplies that have conventional treatment. These disease outbreaks have generally resulted from (1) source contamination and the breakdown of one or more of the treatment barriers, (2) contamination of the distribution system, or (3) the use of untreated water. Box 3-2 describes how the failure of a water filtration plant and other factors contributed to a massive outbreak of the pathogenic protozoan Cryptosporidium in Milwaukee in 1993. Although treatment has reduced the incidence of waterborne disease in the United States since the nineteenth century, waterborne pathogens continue to pose a significant threat to public health in this country. Numerous outbreaks of waterborne disease are reported each year to the Centers for Disease Control and Prevention and represent only a fraction of the true burden of waterborne disease. Evidence of endemic waterborne disease comes from recent epidemiologic studies (described in Chapters 4 and 6 of this report).

Chemical-Related Health Effects

Although microbes cause the bulk of the waterborne disease in this country, chemicals also cause problems. For example, according to Craun and McCabe (1973), during the period 1946–1970, four chemical poisonings occurred in public supplies and eight occurred in private supplies (individual wells). Between 1961 and 1970, there were two and seven documented outbreaks in public and private supplies, respectively. In addition to acute poisonings, many chemicals cause chronic problems. For example, exposure of the human body to arsenic leads to both skin and lung cancer and nervous system toxicity. Of the known chronic problems, cancer is thought by many to be the most serious.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

BOX 3-2
Outbreak of Cryptosporidiosis in Milwaukee

In 1993, the largest documented outbreak of waterborne disease in United States history, affecting an estimated 403,000 people, occurred in Milwaukee, WI. This outbreak is noteworthy for several reasons: (1) it involved a newly recognized waterborne pathogen, Cryptosporidium, (2) Cryptosporidium oocysts were detected in historical samples of ice so that past waterborne exposure could be estimated, (3) drinking water met standards for total coliforms and average turbidity, (4) the Milwaukee public water supply used standard water treatment processes of coagulation/flocculation, filtration, and disinfection; and (5) the frequency of testing patients for Cryptosporidium in this community was inadequate to detect this outbreak (MacKenzie et al., 1994).

The outbreak was first recognized around April 5, 1993, after reports of numerous cases of gastroenteritis and high rates of absenteeism in schools and hospital employees. Initially many cases were misdiagnosed as ''intestinal flu" on the basis of the clinical symptoms and were not further investigated. Because laboratory testing for Cryptosporidium was not a routine procedure, recognition of Cryptosporidium as the causative agent of this outbreak was delayed. From March 1 through April 16, a total of 2,300 stool specimens were submitted to the 14 clinical laboratories in the Milwaukee area for routine examination of enteric pathogens. Twelve of these laboratories tested for Cryptosporidium only at the request of the physician, and by April 6, only 42 stool specimens had been examined for Cryptosporidium (29 percent were positive). On April 7, two laboratories identified Cryptosporidium oocysts in the stools of 7 adults in the Milwaukee area and, at the request of public health officials, the other 12 laboratories began to test all stool specimens for Cryptosporidium. From April 8 through April 16, Cryptosporidium oocysts were detected in 331 of 1,009 specimens (33 percent). Between March 1 and May 30, 739 Cryptosporidium infections were detected by the 14 laboratories.

Persons with laboratory-confirmed cases of Cryptosporidium infection with illness between March 1 and May 15 (N = 285) were compared with 201 persons who had experienced watery diarrhea during the same time period (as identified from telephone surveys in the Milwaukee area). The epidemiologic features and dates of illness were similar in both groups and suggested that many of the watery diarrhea cases were also caused by Cryptosporidium.

The total extent of the outbreak was estimated on the basis of a random digit telephone survey of 840 households in the greater Milwaukee area. Of the 1,663 respondents, 26 percent reported watery diarrhea in the period from March 1 though April 28. By extrapolating this rate to the total population of the greater Milwaukee area (1.6 million people) and

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

subtracting a background rate of diarrhea of 0.5 percent per month (16,000 cases), it was estimated that 403,000 cases of Cryptosporidium were associated with this outbreak.

An early survey of nursing home residents, a relatively immobile population, indicated that Cryptosporidium infection was significantly higher during the first week of April among nursing homes supplied by water from the southern treatment plant. The household telephone survey provided additional information on the geographical distribution of the cases. The risk of watery diarrhea was 2.7 times higher among residents of the Milwaukee Water Works service area than it was among residents outside the service area. Within the service area, the highest attack rate (52 percent) was among residents served by the southern water treatment plant, and the lowest attack rate (26 percent) was among residents served by the northern water treatment plant. Residents that lived in the middle of the service area and could be exposed to water from either or both treatment plants reported an infection rate of 33 percent.

The Milwaukee Water Utility supplies water to approximately 800,000 people (Fox and Lytle, 1996). Two treatment plants treat Lake Michigan source water by conventional treatment processes including coagulation, sedimentation, filtration, and disinfection with chloramines. Waterborne transmission was suspected by April 7, when public health officials issued a boil water advisory and then closed the southern water treatment plant on April 9. The southern plant had observed highly variable treated water turbidity since around March 21, with peaks of 1.7 NTU on March 28 and March 30 and 2.7 NTU on April 5. Consumer complaints about poor quality drinking water were also reported to the Milwaukee Water Works during this period (Milwaukee Journal, 1993). At all times during this period, samples of treated water were negative for coliforms and met the Wisconsin regulations for turbidity. Investigation of the water treatment plant determined no evidence of an obvious mechanical breakdown in the flocculation and filtration system. However, difficulty in determining the appropriate dose of coagulant to aggregate particulates, failure to continuously monitor the turbidity from each filter bed, and recycling of filter backwash water were cited as possible factors contributing to this outbreak. In particular, the southern plant had switched to using a polyaluminum chloride coagulant in August 1992 in order to have a higher finished water pH for corrosion control, to reduce sludge volume, and to improve coagulation effectiveness for cold raw water conditions (Fox and Lytle, 1996). When challenged with heavily contaminated raw water, the plant had little experience in adjusting the dosage of the polyaluminum chloride to optimize the chemical coagulation conditions. Jar-test data and consultation with the chemical supplier were used to guide adjust-

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

ments to the coagulant dosage in response to fluctuations in turbidity. However, the short residence time for the water in the plant and the rapidly changing influent water quality made dosage optimization difficult, and on April 2 the operators switched back to alum as the primary coagulant.

Methods to detect Cryptosporidium oocysts in water are laborious and relatively inefficient. In this outbreak investigation, samples of ice made on March 25 and April 9 were melted and filtered to concentrate Cryptosporidium oocysts that were later detected by an immunofluorescent technique. Estimates of oocyst concentrations in these samples ranged from 2.6 to 13.2 oocysts per 100 L and from 0.7 to 6.7 oocysts per 100 L for March 25 and April 9, respectively. However, the epidemiologic data suggested that these may have been gross underestimates of contamination (possibly because of the effect of freezing and thawing on the oocysts and/or poor recovery from the filters). This is based on the fact that visitors to the Milwaukee Water Works service area who only consumed very small amounts (≤ 240 mL) of water developed laboratory-confirmed cryptosporidiosis.

The source of the Cryptosporidium oocysts and the timing of the water contamination are still unknown. The number of cases with onset of illness before March 23 (when the filtered turbidity increases were noted) indicates that oocysts must have entered the water supply before the turbidity rise. Speculation about the effect of heavy rains and runoff from cattle farms and slaughterhouses into nearby rivers and Lake Michigan has yet to be confirmed. Several water treatment plants along Lake Michigan reported turbidity problems during March and April 1993 (Fox and Lytle, 1996).

Several public health recommendations came from this investigation. The adequacy of current microbiological water standards and the turbidity standard to protect the public from waterborne transmission of enteric protozoa was questioned. Continuous monitoring of treated water for turbidity and tightening the turbidity standard to ≤0.1 NTU were recommended. Particle counting was also suggested as a tool for monitoring treatment performance (Fox and Lytle, 1996). Changes in water treatment procedures related to filter maintenance and backwashing were implemented, and laboratory facilities for Cryptosporidium monitoring of raw and finished waters were established. MacKenzie et al. (1994) advocated the routine examination for Cryptosporidium oocysts in stools, although the infection is self-limited in the immunocompetent host and no effective treatment is available. Furthermore, the study's authors advised making cryptosporidiosis a reportable disease to improve the recognition of Cryptosporidium outbreaks in the United States. The AWWA (1993) observed that media coverage during the outbreak "may have influenced the public's agenda of concerns and made water quality a more salient issue."

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

The potential for chemicals in drinking water to cause cancer plays a major role in determining maximum contaminant levels (MCLs) and maximum contaminant level goals (MCLGs) set by the Environmental Protection Agency (EPA). MCLGs are nonenforceable standards, specified for all chemicals, that correspond to contaminant concentrations at which no known or anticipated adverse health effects will occur. For carcinogens and pathogens, MCLGs have currently been set at zero in order to provide complete public health protection. For some contaminants, EPA has developed MCLs, which are enforceable concentrations of chemicals that must not be exceeded in a drinking water supply. By law, a contaminant's MCL must be set as close to its MCLG as practicable.

MCLs represent minimum requirements for defining "safe" drinking water. Because our understanding of the health effects of contaminants will improve, today's standards are likely to differ from future standards. As a consequence, many forward-thinking water utilities strive to produce drinking water of better quality than the minimum safety requirements represented by MCLs.

Water utilities must monitor the concentrations of a large number of regulated contaminants. Most of these contaminants, such as pesticides, gasoline components, and cleaning solvents, are usually present at levels below their detection limit. However, one class of carcinogenic chemicals—disinfection byproducts (DBPs)—is commonly found at detectable levels in distributed drinking water.

Disinfection Byproducts

In the early 1970s, J. Rook discovered that free chlorine, a common drinking water disinfectant, reacts with nontoxic natural organic matter (derived mainly from decaying vegetation and associated fulvic and humic acids) to form trihalogen-substituted single carbon organic compounds (DBPs). Initially, only four DBPs were identified—the trihalomethanes (THMs) chloroform (trichloromethane), bromodichloromethane, dibromochloromethane, and bromoform (tribromomethane). Early animal testing indicated that chloroform was a suspected human carcinogen via ingestion. In spite of the lack of information on the health effects of bromodichloromethane, dibromochloromethane, and bromoform, EPA decided in 1979 to regulate all four compounds as a group because (1) they were all formed by the same mechanism, (2) all of the compounds were expected to show adverse health effects once testing was performed, and (3) the techniques for controlling their concentration were the same.

Intense study of DBPs over the last 25 years has added greatly to our knowledge of this issue. Among the more important findings has been the discovery that many more byproducts are formed when free chlorine reacts with natural organic matter than the four THMs originally identified. As of 1998, nearly 30 different organic byproducts have been identified, and even more are likely to exist. A comparison of identified compounds in chlorinated drinking waters to

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

the total amount of halogen substitution, as measured by the group parameter total organic halogen, indicates that only about a third (on average) of the byproducts formed have been identified (Singer et al., 1995).

Another important outcome of DBP research has been the discovery of another group of nine compounds formed in concentrations near or in excess of THMs. These are the mono-, di-, and trihalogen-substituted acetic acids, or haloacetic acids (HAAs). As it has done with THMs, EPA is regulating HAAs as a group because the control techniques for each compound in the group are similar.

Evidence is mounting to show that the health effects of individual compounds within the DBP groups are quite variable. Box 3-3 contains a summary of the current known health effects of DBPs formed subsequent to chlorination of drinking water.

Treatment Options for Controlling DBPs

Water utilities faced with the challenge of controlling DBPs have two basic choices: (1) they can change to a disinfectant that is a weaker halogenating agent than free chlorine (such as chloramines) or to a non-halogen-containing disinfectant (such as ozone), or (2) they can control the concentrations of the natural organic matter precursors with which free chlorine reacts. The use of alternate disinfectants can pose considerable problems. Ozone is difficult to maintain in a water supply distribution system because of its rapid degradation. In addition, it can create ozone byproducts (e.g., bromate) and biodegradable organic matter, the latter of which can promote bacterial regrowth in the distribution system. Chloramines are weaker oxidants than chlorine; they are of lower effectiveness against viruses and Giardia, and they are virtually useless against Cryptosporidium. In addition, chloramines also produce DBPs, notably the dihalogen-substituted acetic acids. Chlorine dioxide, another possible disinfectant, can lead to the accumulation of chlorite and chlorate in water supplies, both of which pose health risks. Water supplies relying on alternate disinfectants are attempting to overcome these obstacles by using multiple, sequential chemical applications, such as ozone followed by chloramines.

At the present time, the most common long-term approach to preventing the formation of DBPs is precursor control. Lowering concentrations of humic and fulvic acids in stormwater and lowering concentrations of algae in water supply reservoirs are important first steps. Once in the source water, the only way to ensure removal of DBP precursors is by treatment prior to chlorination, for example by the addition of coagulants to promote settling of natural organic matter in turbid waters or by coagulation/filtration.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

BOX 3-3
Summary of the Health Effects of DBPs Derived from Chlorination

Cancer

Bladder, colon, and rectal cancer may be associated with drinking chlorinated water (EPA, 1998a, p. 69394). Bladder cancer has received considerable attention because of the abundance of high-quality studies compared to other types of cancer. According to EPA, the number of potential bladder cancer cases that could be associated with exposure to DBPs in chlorinated surface water is estimated to be in an upperbound range of 1,100–9,300 per year (EPA, 1998b). However, given past epidemiological studies, there are insufficient data to conclusively demonstrate a causal association between exposure to DBPs in chlorinated surface water and cancer. Nonetheless, EPA believes the overall weight of evidence from available epidemiological and toxicological studies on DBPs and chlorinated surface water supports a hazard concern and has therefore decided to regulate these compounds as a prudent public health measure.

Chloroform. Since 1996, EPA has advocated a nonlinear approach for estimating the additional lifetime carcinogenic risk associated with exposure to chloroform via drinking water. However, after considerable debate, the current MCLG for chloroform currently stands at zero (EPA, 1998c). EPA believes that the MCL of 0.080 mg/L for THMs is appropriate for the protection of the public from chloroform. The current MCL is thought to not only provide protection against chloroform, but also to provide protection against several other potentially hazardous DBPs, such as bromodichloromethane and bromoform.

Dichloroacetic Acid. Since 1994, EPA has maintained that dichloroacetic acid (DCA) is a probable human carcinogen (i.e., a Group B2 carcinogen). Because the data needed to determine a dose-response relationship for DCA are inadequate, the MCLG for this compound remains at zero to assure maximum public health protection (EPA, 1998d).

Adverse Reproductive and Developmental Effects

A recent study has demonstrated that consumption of tap water containing high concentrations of THMs, particularly bromodichloromethane, is associated with an increased risk of early-term miscarriage (Waller et al., 1998). Although this association did not constitute proof that exposure to THMs causes early term miscarriages, miscarriage has added to

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

the list of possible adverse effects of DBPs on human health. Examining the relationship between DBPs and adverse reproductive and developmental effects is the primary activity of EPA's epidemiology and toxicology research program. In addition to conducting follow-up studies to the 1998 Waller et al. report, EPA is working with the California Department of Health Services to improve estimates of exposure to DBPs in a study population by developing a DBP exposure database. EPA is also collaborating with the Centers for Disease Control and Prevention (CDC) and the National Toxicology Program to screen individual DBPs for reproductive and developmental effects. In addition to miscarriage, the effect of bromodichloromethane on male reproduction is being investigated. Data gathered from these efforts will be used to tighten regulatory goals for both THMs and HAAs.

Ecological and Aesthetics Considerations

Although adverse health impacts are of primary importance, additional concerns about the quality of a drinking water supply include taste, odor, color, and turbidity. In addition, eutrophication of water supply reservoirs caused by nutrient enrichment can negatively affect both human and ecological receptors in multiple ways. All these problems are directly or indirectly related to biological growth within water supply reservoirs and to how that growth responds to changing environmental conditions.

Drinking Water Aesthetics

The public expects its drinking water to be clear and free of taste and odors. Pure water is a neutral medium and alone cannot produce either odor or taste sensations. The compounds responsible for water taste and odor include most organic and some inorganic chemicals, although some substances (e.g., certain inorganic salts) produce taste without odor. Nearly all the natural compounds that generate offensive tastes and odors in water are the result of dissolved organic substances released by actively growing microorganisms or released during decomposition of algae and higher vegetation. Although a number of assays exist to estimate the relative taste and flavor quality of water, most are highly subjective (e.g., American Public Health Association, 1995). (It should be noted that drinking water held for long periods within the distribution system can also acquire tastes and odors from metals and from organic compounds released by microorganisms within the distribution system.)

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

The quality of water is affected by both color and turbidity. The observed color of water is the result of light being scattered upward after it has passed through the water and has undergone selective absorption en route. In pure water, molecular scattering of light is a function of frequency, making the high-frequency color blue the dominant observed color. Beyond these physical factors, most of the true color of natural waters results from dissolved organic compounds such as humic and fulvic acids, which are derived from the partial decomposition of structural tissues of higher plants. Waters containing large amounts of dissolved organic compounds have a light yellow or brown organic tint. Under certain conditions of high acidity, natural metallic ions (iron and manganese) can result in a variety of water colors.

Because of its importance in determining consumer satisfaction, color in drinking water is routinely measured. Color has two decisive characteristics—color intensity (brightness) and light intensity (lightness)—that make discriminating between colors extremely subjective. For this reason, a number of color scales have been devised to empirically compare the true color of lake water, after filtration to remove suspended particles (cf. Wetzel and Likens, 1991; American Public Health Association, 1995). Consumers generally do not complain about drinking water with a color indicator of less than 15 Standard Color Units (SCU) (NYC DEP, 1999).

Turbidity in natural waters is caused by suspended and colloidal particulate matter such as clay, silt, and other finely divided inorganic and organic (both living and dead) matter. These particles scatter light of specific wavelengths and can be responsible for the observed color of water supply reservoirs. For example, colloidal CaCO3, common to hard-water lakes and some of the New York City reservoirs, scatters light in the greens and blues and gives these waters a very characteristic blue-green color. Although some turbidity is generated by phytoplankton in water supply reservoirs, most turbidity problems emanate from watershed erosion during heavy precipitation events. Although low to moderate levels of turbidity are not generally harmful to human health, excessive levels (above 5 NTU) are considered aesthetically displeasing and will result in consumer complaints.

Eutrophication

Eutrophication is a general term that refers to an array of conditions associated with increased growth and productivity of organisms in aquatic ecosystems. Eutrophication occurs when elevated supplies of macronutrients, particularly phosphorus and nitrogen, are delivered to surface waters. These nutrients promote the growth of algae, photosynthetic and heterotrophic bacteria, and higher aquatic plants. The increased production of algae and their associated organic matter can negatively alter conditions within the reservoirs in many ways. Turbidity may be affected because of the presence of algal material and algal

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

byproducts. The increase in total organic carbon derived from algal biomass can lead to formation of DBPs in the water distribution system. Algae can produce potentially toxic compounds, some of which may create taste and odor problems. And heterotrophic bacteria introduced by natural or human sources can consume the increased dissolved organic matter, thereby depleting dissolved oxygen levels within the reservoirs and destroying fish habitat.

In the past several decades, society has recognized the cost effectiveness of reducing pathogen, chemical pollutant, and nutrient loadings to recipient lakes and reservoirs for maintenance of high water quality. Relatively simple control measures within drainage basins can be implemented to minimize pollutant loadings, and such measures are often much more economical than treating degraded water supplies.

FEDERAL ENVIRONMENTAL REGULATIONS

One of the most important mechanisms used to ensure the delivery of safe drinking water is enforcement of environmental regulations. Water supplies must comply with a plethora of environmental regulations stemming from the Clean Water Act (CWA, 33 USCA, Section 1151 et seq., 1972) and the 1974 Safe Drinking Water Act (SDWA), laws passed in response to degraded water quality in major bodies of water and drinking water across the country. These laws target microbial pathogens and associated waterborne disease, chemical contaminants of drinking water, and aesthetic and ecological considerations related to water quality. The CWA focuses jointly on human and aquatic ecosystem health by establishing a water quality standard of "fishable and swimmable" that is applied to all bodies of water, including sources of drinking water. The SDWA focuses on human health by setting drinking water standards, a process that began as early as 1925. Most of the federal laws written since 1970 have been amended several times to incorporate new science and technology. For example, amendments to the SDWA require regulation and monitoring of new biological and chemical contaminants. Table 3-5 shows how federal regulations regarding water quality have evolved during the 20th century.

Over the last ten years, there has been a growing interest in taking a watershed approach to evaluating water quality. This is particularly true within EPA, which has developed a watershed framework (EPA, 1996; NRC, 1999). In general, there are no federal laws mandating watershed management for source water. However, rules developed from the 1996 SDWA amendments require states to assess watershed conditions and create watershed control programs for surface water supplies that are not filtered. A number of bills have been proposed in Congress that would mandate the watershed approach on a more widespread basis, but none has yet made it into law.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

TABLE 3-5 Federal Regulations Timeline

1893

Interstate Quarantine Act

1899

Rivers and Harbors Act

1912

First drinking water-related regulation (McDermott, 1973).

1914

First federal drinking water standards, binding only to interstate carriers (Borchardt and Walton, 1971).

1925

First inclusion of chemicals in drinking water standards (U.S. Public Health Service, 1925).

1946

Hexavalent chromium added to list of regulated drinking water contaminants.

1948

Federal Water Pollution Control Act

1962

Last drinking water standards issued by the U.S. Public Health Service under the Interstate Quarantine Act; 28 regulated contaminants; microbial standards binding only on about 700 interstate carrier systems; chemical standards nonbinding.

1972

Federal Water Pollution Control Act Amendments (P.L. 92-500)

1974

First publications on formation of trihalomethanes following chlorination.

1974

Safe Drinking Water Act (P.L. 93-523). Specified drinking water regulations that apply to all community water supplies.

1975

Interim Primary Drinking Water Regulations, based on the 1962 U.S. Public Health Service drinking water standards.

1977

Clean Water Act (P.L. 95-217). This law amends the Federal Water Pollution Control Act.

1979

Reauthorization of the SDWA (P.L. 96-63).

1979

Trihalomethane final rule.

1983

First use of the term "best available technology" (BAT).

1986

Fluoride final rule.

1986

SDWA amendments (P.L. 99-339). 83 specified contaminants must be regulated. 25 additional contaminants are to be added every three years.

1987

Volatile organic contaminants, final rule.

1988

Lead Contamination Control Act (P.L. 100-572)

1989

Surface Water Treatment Rule, final rule.

1989

Total Coliform Rule, final rule.

1991

Lead and Copper Rule, final rule.

1996

Information Collection Rule, final rule.

1996

SDWA amendments (P.L. 104-182) Eliminated requirement for 25 new regulated contaminants every three years. Requires development of Candidate Contaminant List.

1998

Drinking Water Candidate Contaminant List, final.

1998

Consumer Confidence Reports, final rule.

1998

Stage 1 Disinfectants/Disinfection By-Products Rule, final rule.

1998

Interim Enhanced Surface Water Treatment Rule, final rule.

Note: Bolded entries indicate federal statutes.

Safe Drinking Water Act

In the early 1970s, several scientific factors came together that prompted Congress to draft legislation on drinking water quality. First, a community water supply study showed that 41 percent of 969 water supplies did not meet current drinking water standards set by the U.S. Public Health Service (McCabe

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

et al., 1970). Further evidence of drinking water contaminated by organic compounds was found in New Orleans (Harris and Brecher, 1974). Meanwhile, ongoing research in the Netherlands and at an EPA research laboratory confirmed that chlorine could combine with harmless natural organic compounds in water to produce chloroform and other THMs (Bellar and Lichtenberg, 1974; Rook, 1974). During the same time period, the National Cancer Institute, announced that chloroform was a suspected human carcinogen (National Cancer Institute, 1976). These combined factors led Congress, after four years of effort, to pass the SDWA in 1974.

The SDWA contains multiple provisions for assessing, and preventing biological and chemical contamination of drinking water supplies, both surface water and groundwater. In addition to other requirements, drinking water suppliers must abide by a variety of rules that target specific contaminants and water supplies. The most recent reflect EPA's desire to balance the risks of microbial pathogens with risks from chemical contaminants, most notably DBPs.

Surface Water Treatment Rule

The Surface Water Treatment Rule (SWTR, 40 CFR Part 141), promulgated by EPA on June 29, 1989, requires that all surface water systems treat their water by filtration unless it can be proven to be unnecessary. The SWTR describes improved criteria for filtration and disinfection treatment processes to control for Giardia and viruses. In doing so, two important metrics of success for treatment operations are introduced: (1) log removal of microbial pathogens, which refers to a decrease in an organism's concentration by a factor of ten, and (2) CT, the product of disinfectant concentration (C) and the contact time (T), as the control parameter for disinfection.

For those water supply systems that were not filtering at the time of the SWTR promulgation, the rule requires such systems to either begin filtration or develop a monitoring program demonstrating that filtration is unnecessary. Continued avoidance of filtration is a possibility, provided that a water supply system satisfies a variety of conditions outlined below. These conditions (and other important criteria) are documented in a Filtration Avoidance Determination (FAD) that is issued by EPA to the water supply system.

Source Water Quality. Avoidance of filtration is intended to be applicable only to those waters that have historically excellent water quality, as measured by a variety of parameters. Prior to disinfection, the fecal coliform concentration in the source water must be less than 20 colony forming units (CFU)/100 mL in at least 90 percent of the samples taken, or the total coliform density must be less than 100 CFU/100 mL in at least 90 percent of the samples taken. These data must be based on monitoring results during the previous six months. For utilities

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

serving a population of over 25,000, a minimum of five coliform samples must be taken each week.

Turbidity of the source water prior to disinfection cannot exceed 5 NTU, based on continuous sampling or grab samples collected every four hours that the system is in operation. A system occasionally may exceed the 5-NTU limit and still avoid filtration as long as (1) the state determines that each event occurred because of unusual or unpredictable circumstances and (2) not more than two such events have occurred in the past 12 months, or not more than five such events in the past 120 months. An event is defined as a series of consecutive days in which at least one turbidity measurement each day exceeds 5 NTU. If the system is unable to comply with these criteria, it is required to install filtration.

Disinfection Criteria. Disinfection of unfiltered water must achieve 99.9 percent (3-log) inactivation of Giardia cysts and 99.99 percent (4-log) inactivation of viruses. The effectiveness of the disinfection process must be demonstrated every day by meeting minimum CT values specified in the SWTR guidance manual (EPA, 1990). Filtration must be installed if the system fails to meet this requirement on more than one day a month, during two or more months within a consecutive 12-month period.

In order to prevent regrowth of bacteria in the distribution system, the SWTR requires that a ''residual" concentration of disinfectant exist in all finished waters. The disinfectant residual at the entry point of the distribution system water cannot be less than 0.2 mg/L for more than 4 hours. If the residual at the entry point falls below 0.2 mg/L for any length of time, the water utility must notify the state, regardless of the type of disinfectant used. Continuous monitoring for disinfectant residual is required of systems serving more than 3,300 persons.

Deeper within the distribution system, the disinfectant residual cannot be undetectable in more than 5 percent of the samples in a month for any two consecutive months that the system serves water to the public. A system may measure for heterotrophic plate count (HPC) in lieu of disinfectant residual in the distribution system. A sampling site with an HPC level of less than 500 CFU/mL is considered to have a "detectable" residual for compliance purposes. Finally, systems providing disinfection as the only treatment must provide redundant disinfection equipment. This includes auxiliary power, automatic start-up, and an alarm or an automatic shutoff of water delivery to the distribution system when the disinfectant residual level at the entry point drops below 0.2 mg/L.

Site-Specific Criteria. Four other extremely important criteria have been established for unfiltered water supply systems. First, an effective watershed control program must be established and maintained. Second, an annual on-site inspection conducted by the state (or a third party approved by the state) is required. This inspection must consider the effectiveness of the watershed control program, the condition and protection of the source intake(s), the physical

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

condition of operating equipment, the adequacy of operating procedures, the existence of monitoring records, and areas for improvement. Third, an unfiltered system must demonstrate an absence of waterborne disease outbreaks. If the system has been identified as the source of a waterborne disease, then it must be modified sufficiently to prevent further outbreaks. Finally, the water supply system must comply with the total coliform and total trihalomethane MCLs.

Total Coliform Rule

The purpose of the Total Coliform Rule (TCR) is to prevent waterborne microbial disease by requiring water suppliers to test drinking water for potentially harmful microorganisms. The total coliform group of bacteria is used to indicate the presence or absence of pathogenic organisms. Measurements of total coliform are often supplemented by the more specific bacterial indicators, fecal coliforms and Escherichia coli.

For water systems analyzing at least 40 water samples per month, no more than five percent of the samples may be positive for total coliforms, while for systems analyzing fewer than 40 samples per month, no more than one sample per month may be positive. In addition, if repeated testing of a water sample demonstrates sequential positive tests for total or fecal coliforms, the water supply is considered out of compliance with the TCR (Pontius, 1990). Total coliform measurements are generally made at the same frequency and locations as measurements for disinfectant residual (EPA, 1989).

Lead and Copper Rule

The Lead and Copper Rule (LCR) requires increased evaluation of treatment processes that control corrosion, with the goal of optimizing these processes. Several chemical additives are commonly used in water supply systems to prevent the chemical and biological corrosion of lead and copper pipes. For example, orthophosphate and sodium hydroxide are common additives that increase pH and neutralize corrosion-causing acid compounds. The LCR mandates enhanced sampling of distribution system water to determine the extent of corrosion and the efficacy of treatment processes.

Information Collection Rule

EPA's attempt to balance microbial and chemical risks of drinking water is most apparent in three recent rules that were the product of negotiated rulemaking in the early 1990s: the Information Collection Rule (ICR), the Disinfectants/Disinfection By-Products (D/DBP) Rule, and the Enhanced Surface Water Treatment Rule (ESWTR). The ICR mandates water supply systems to collect water quality data that will be used to form a national database of important parameters

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

such as microbial pathogens and DBPs. These data, which will be available in late 1999, will guide EPA in the development of future drinking water regulations.

Rules following the 1996 SDWA Amendments

The 1996 amendments to the SDWA specified that EPA must promulgate two new rules by November 1998, both of which would substantially impact filtered and unfiltered water supplies (EPA, 1997a,b). The D/DBP Rule is intended to better control concentrations of disinfectants and disinfection byproducts, while the ESWTR is targeted at controlling the pathogenic protozoan Cryptosporidium. The D/DBP Rule will be implemented in two stages (Stage 1 D/DBP and Stage 2 D/DBP); the ESWTR has been broken up into three parts: the Interim ESWTR (IESWTR), the Long-term 1 ESWTR (LT1ESWTR), and the Long-term 2 ESWTR (LT2ESWTR). Target dates for the proposal, promulgation, and enforcement of these rules are shown in Table 3-6.

D/DBP Rule. The D/DBP Rule specifies updated MCLs for total trihalomethanes (TTHMs) and new MCLs and MCLGs for the sum of five haloacetic acids (HAA5) and the inorganic DBPs bromate and chlorite. Bromate has recently become an issue in water supply systems that use ozone as a primary disinfectant. Ozonation can result in the production of bromate in waters that contain bromide. Chlorite in drinking water is also a relatively recent discovery. It can be derived from the breakdown of sodium hypochlorite (NaOC1), or from the primary disinfectant chlorine dioxide.

The Stage 1 MCLs are 0.080 mg/L for TTHM, 0.060 mg/L for HAA5, 1.0 mg/L for chlorite, and 0.010 mg/L for bromate. The rule also specifies new maximum residual disinfectant levels (MRDLs) for chlorine, chloramine, and chlorine dioxide. The upper bound on disinfectant residuals was formerly determined by the taste and odor of the finished water. The MRDL for chlorine, the

TABLE 3-6 Anticipated Regulatory Schedule for the Disinfectants/Disinfection By-Products Rule and the Enhanced Surface Water Treatment Rule

 

Proposed

Final

Effective

Stage 1 D/DBP

1994

Dec. 1998

Dec. 2001

Interim ESWTR

1994

Dec. 1998

Dec. 2001

LT1ESWTR

Nov. 1999

Nov. 2000

Nov. 2003

Stage 2 Reg. Neg.a

Begin 1999

End 2000

 

Stage 2 D/DBP

Nov. 2000

May 2002

May 2005b

LT2ESWTR

Nov. 2000

May 2002

May 2005b

a Negotiated Regulation Process.

b Date uncertain.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

most commonly used primary disinfectant, will be 4 mg/L. Recommendations are given for best available technologies to achieve these new MCLs, MCLGs, MRDLs, and maximum residual disinfectant level goals (MRDLGs).

Although negotiations for the Stage 2 rule are ongoing, "placeholder" MCLs have been discussed for TTHMs and HAA5, and they are stricter than the Stage 1 MCLs. These placeholder MCLs, which represent starting points for the negotiation process, are 0.040 mg/L for TTHMs and 0.030 mg/L for HAA5.

Enhanced Surface Water Treatment Rule. The IESWTR requires a tightening of turbidity MCL requirements for filtered systems from 0.5 NTU to 0.3 NTU. The new turbidity MCL is being required of filtered systems to enhance treatment performance and associated health benefits. (Turbidity happens to be an excellent indicator of filtration performance.) Similar requirements for unfiltered systems, which currently must meet a turbidity requirement of 5 NTU, are not anticipated until the LT2ESWTR. Box 3-4 explains why the turbidity requirements for filtered systems and unfiltered systems differ by more than an order of magnitude.

Although the final ESWTR will not be promulgated soon, several additional issues are likely to be incorporated. Microbial benchmarking will be required of systems that have problems with DBPs.1 A system can be forced to benchmark its disinfection process if either its TTHM or HAA5 levels are 80 percent of the MCL as an annual average. EPA is currently advocating a multiple-barrier approach to pathogen removal that includes source water protection, filtration, and disinfection. To demonstrate that this approach is being used, the ESWTR will require drinking water systems to show that both filtering and disinfection are reducing concentrations of Cryptosporidium, an organism that is currently not regulated as part of the SDWA. Unfiltered supplies will specifically be asked to amend watershed control programs to control for Cryptosporidium.

Drinking Water Candidate Contaminant List. As part of the 1996 amendments to the SDWA, EPA must decide, on a regular basis, whether to regulate new and emerging drinking water contaminants. In order to gather information on the occurrence of new contaminants to assist in these judgments, EPA has issued a Drinking Water Candidate Contaminant List, published on March 2, 1998 (EPA, 1998e). This list contains 50 chemical and 10 microbial contaminants/contaminant groups for possible future regulation. Water utilities will be collecting occurrence data on these contaminants over the next few years.

Source Water Assessment Program. Although much of the SDWA consists of drinking water standards for particular contaminants, some elements of

1  

 This process involves calculating daily levels of Giardia inactivation and plotting them over a year as a "benchmark" of how well the disinfection system is working.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

Box 3-4
Turbidity Requirements under the ESWTR

Under the ESWTR, filtered systems will be required to meet a turbidity MCL of 0.3 NTU while unfiltered systems must meet a turbidity MCL of 5 NTU. The reason for the considerable discrepancy has to do with the impact of turbidity on the primary treatment process. In filtered systems, turbidity is mainly a cause for concern because it indicates ineffective filtration. Lowering the turbidity requirement for filtered systems is seen as a regulatory mechanism to improve the performance of filtration. In unfiltered systems, turbidity is most likely to disrupt the disinfection process. Particles responsible for turbidity have been shown to physically shield pathogens from disinfectants (Symons and Hoff, 1976). Five (5) NTU is thought to be sufficient to prevent turbidity from impairing disinfection. This has been supported by anecdotal evidence from managers of unfiltered systems, who argue that they have not experienced a documented waterborne disease outbreak in complying with the turbidity MCL of 5 NTU.

In the committee's opinion, however, the turbidity standard of 5 NTU for unfiltered systems has not been adequately justified. This is because other factors may increase the relative risk of turbidity in unfiltered systems compared to filtered systems. The particles present in unfiltered source water, as measured by turbidity, are much more dangerous than the particles in filtered water that have escaped filtration. That is, unfiltered water turbidity may contain pathogenic microorganisms, while filtered water turbidity is likely to consist almost entirely of small floc. This difference between turbidity in source waters and turbidity in filtered waters was borne out in Colorado several years ago. At that time, the filtered water turbidity standard was 1.0 NTU. Several water suppliers with relatively clear mountain streams as sources thought that if the source water turbidity was below 1.0 NTU, the resulting drinking water would also meet the turbidity standard. On an occasion when the source water turbidity was below 1.0 NTU, the operators stopped adding coagulant, which prevented filtration from occurring efficiently. This practice resulted in several outbreaks of giardiasis, indicating that sources with turbidities of less than 1.0 NTU are not equivalent to filtered water with a turbidity of 1.0 NTU (Hopkins et al., 1983).

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

the law specify regulations for watershed management. In particular, the 1996 SDWA amendments established a new state program, the source water assessment program (SWAP), to provide a strong basis for developing, implementing, and improving source water protection. State source water assessment programs were submitted to EPA for review by February 6, 1999, and implementation of the programs should begin immediately after their approval. A major goal of the SWAP is to delineate the boundaries of watersheds that supply drinking water systems, using all reasonably available hydrogeologic information. Once these areas are defined, the SWAP should determine the susceptibility of public drinking water systems in these areas to regulated contaminants (and unregulated contaminants as specified by the state) (Pontius, 1997).

Enforcement Authority

EPA is required by law to allow states to assume responsibility for implementing and enforcing the SDWA. In order to obtain this responsibility, known as primacy, states must pass, implement, and enforce laws that EPA must review and approve. If state policies are not approved, enforcement responsibilities for the SDWA remain with EPA.

Like most states, New York has primacy for the SDWA, which is delegated to the New York State Department of Health (NYS DOH). However, given the unfiltered status of the Catskill/Delaware water supply, EPA was asked to retain SDWA primacy specifically for this system until May 15, 2007. For all other public water supplies in New York State, NYS DOH is the primary enforcement agency.

Clean Water Act

The CWA is the act under which EPA regulates the quality of the nation's surface waters, including wetlands. In addition to strengthening the nation's water quality standards system, this legislation regulates discharges into bodies of water, it encourages the use of the best available technology for pollution control, and in the past it provided billions of dollars for construction of wastewater treatment plants (WWTPs). Thus, while the SDWA targets the quality of drinking water at or near the point of use, the CWA focuses more on the quality of source waters and on discharges into those waters.

The CWA has two primary objectives: (1) to regulate the discharge of pollutants into the nation's waters and (2) to achieve water quality levels that are fishable and swimmable. The act and accompanying regulations from EPA provide a comprehensive framework of standards, technical tools, and financial assistance to address the many causes of poor water quality, including municipal and industrial wastewater discharges, polluted runoff from urban and rural areas, hydrologic modification, and habitat destruction.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×
Water Quality Standards

The CWA requires states to establish specific water quality standards appropriate for their waters and to develop pollution control programs to meet these standards. First, the states must designate their waters by a use classification such as drinking water, aquatic life, recreational, or industrial, among others. Second, they must designate narrative and numeric water quality criteria for specific chemicals that correspond to the particular use classifications. Both these measures constitute water quality standards (i.e., use classification + water quality criteria = water quality standard). Every two years, the states must report to EPA the overall health of their waters and whether the waters are meeting water quality standards. The water quality parameters that are most important for a drinking water supply include certain microbes, turbidity, nutrients, total organic carbon, and toxic compounds, examples of which are listed in Table 3-7.

Water quality standards across the states vary considerably for specific parameters. Obviously, for waters with different use classifications, there are variable water quality criteria. For example, in New York, a Class A, AA, B, or C water must not exceed 190 µg/L dissolved arsenic, while a Class D water must not exceed 360 µg/L dissolved arsenic. For those waters that have been classified as a drinking water source, the water quality criteria that must be met are sometimes MCLs. For those parameters that do not have an MCL, there can be considerable variability among the states regarding the allowable concentrations of these pollutants. Table 3-7 compares seven states' water quality criteria for surface waters that are a source of drinking water. A comprehensive list of New York's water quality standards is found in Appendix B.

For the common source water parameters listed in Table 3-7, there is some chemical-specific variation among the seven states. New York State standards are similar to those of Virginia and North Carolina, eastern states with a significant number of surface water supplies. All three states have narrative standards for nitrogen and phosphorus, although New York has interpreted its narrative standard for phosphorus into a guidance value of 20 µg/L.

It should be kept in mind that not all the water quality standards for the parameters listed in Table 3-7 are based on drinking water uses. For example, the New York standard for phosphorus is based on aesthetics and contact recreation, while the chlorine and ammonia standards listed for all states are based on fish survival and propagation. Interestingly, the western states (except for Washington) have slightly less stringent water quality criteria than the eastern states, making water treatment more important to those states and deemphasizing the role of source water protection.

Total Maximum Daily Loads

Many waters are not currently meeting their designated beneficial uses established by states to satisfy Section 303 of the CWA. For those waters that are

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

TABLE 3-7 State Water Quality Standards for Surface Waters Used as a Source of Drinking Water (all values in mg/L unless specified otherwise)

Parameter

New Yorka

Arizonab

Coloradoc

North Carolinad

Utahe

Virginiaf

Washingtong

Fecal Coliform

monthly geo. mean: < 200/100 mL

1,000 per 4,000 mL

mean: 2,000/100 mL

monthly geo. mean: < 50–200/100 mL

max: 2,000/100 mL

monthly geo. mean: < 200/100 mL

mean: 100/100 mL

Phosphorus

Narrativeh

 

 

Narrativei

0.025

Narrativej

 

Nitrogen

Narrativeh

 

 

Narrativei

 

Narrativej

 

Chlorinek

0.005

 

 

0.017

 

0.011

 

Chloroforml

0.007

 

 

 

 

 

 

Ammoniak

2

 

0.5

 

 

0.08-2.5

 

DOm

> 5

6.0

3.0

> 5

5.5

> 5

8.0

pH

6.5–8.5

5–9

5–9

6–9

6.5–9

6–9

6.5–8.5

Mercuryn

0.002

0.002

 

1.2×10-5

 

5×10-4

 

a NYS DEC (1994).

b Arizona Department of Environmental Quality (1996).

c Colorado Department of Public Health and the Environment (1996).

d North Carolina Department of Environment and Natural Resources (1998).

e Utah Department of Environmental Quality (1994).

f Virginia Department of Environmental Quality (1988).

g Washington Department of Ecology (1993).

h None in amounts that will result in the growth of algae, weeds, and slime that will impair the waters for their best uses, currently interpreted by the NYS DEC to be 20 µg/L.

i For those waters classified as nutrient-sensitive waters, no increase over background levels.

j Nonspecific narrative for nutrients.

k Chlorine and ammonia standards based survival of aquatic species.

l Chloroform standard in New York State based on carcinogenicity.

m Dissolved oxygen standards become stricter for waters supporting trout habitats.

n The MCL for mercury is 0.002 mg/L.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

out of compliance, the states must develop Total Maximum Daily Loads (TMDLs). A TMDL is a written, quantitative assessment of water quality problems and contributing pollutant sources. It specifies the amount of a pollutant or other stressor that needs to be reduced to meet water quality standards, allocates pollution control responsibilities among pollution sources (both point and nonpoint) in a watershed, and provides a basis for taking actions needed to restore a body of water. NYC DEP has developed phosphorus TMDLs for all of the drinking water reservoirs in the Croton and Catskill/Delaware watersheds.

Current regulations require states to submit lists of impaired waters every two years and to target those waters for which TMDLs will be developed during the next two years. Not all states have successfully met these strict requirements, subjecting the TMDL program to considerable controversy. The most debated issue is whether EPA can enforce the implementation of nonpoint source pollution control measures to reach TMDLs. Opponents argue that Section 303d is not applicable to nonpoint source pollution because such language is not specifically found within the CWA (Larson, 1999; Water Report, 1999). Supporters argue that the TMDL program should regulate nonpoint source pollution because voluntary implementation of nonpoint source pollution control measures has met with limited success.

Nonpoint Source Pollution

As suggested above, there is currently no regulatory mechanism by which EPA can control nonpoint source pollution, a position that has recently been upheld in federal courts for some sections of the CWA (Larson, 1999). Unlike point source pollution, nonpoint source pollution is not derived from a single discharge point, such as industrial and sewage treatment plants, but rather from diffuse sources. It can originate from agricultural and construction activities, on-site sewage treatment and disposal systems, and atmospheric deposition, among others. Nonpoint source pollution enters nearby water from dry and wet atmospheric deposition and from runoff that has collected nutrients, toxic chemicals, sediment, and microorganisms from the land.

Section 319 of the CWA encourages states to implement programs for nonpoint source pollution control by offering grant assistance for development and implementation. Future attempts by EPA to regulate nonpoint sources of pollution are likely to stem from section 303(e) of the CWA, which might be used as a "framework for implementing TMDLs, especially the nonpoint source load allocations" (EPA, 1997c). EPA is suggesting revisions of state nonpoint management programs under Section 319 and may take even stronger steps, such as reduction of federal grant dollars to states that fail to carry out nonpoint source implementation measures (EPA, 1997c).

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×
NPDES Permits

All discharges to waters of the nation (point sources) are required to meet performance standards and effluent quality standards. This is accomplished through the CWA's National Pollutant Discharge Elimination System (NPDES) program. The NPDES program requires EPA (or the states with delegated programs) to issue enforceable permits for point source discharges such as industrial process wastewater, municipal WWTPs, or stormwater discharges from urban areas. Permits also regulate industrial point sources and concentrated animal feeding operations that discharge into other wastewater collection systems or that discharge directly into receiving waters. More than 200,000 sources are regulated by NPDES permits nationwide. In New York, the state issues the permits, which are referred to as SPDES (State Pollutant Discharge Elimination System) permits. There are 41 sewage treatment plants and seven industrial treatment plants in the Catskill/Delaware watershed and 85 WWTPs in the Croton watershed that operate under SPDES permits (Marx and Goldstein, 1993).

When the NPDES program was created, most effluent limits were specified for technology-based parameters that measure the performance of a WWTP, such as biological oxygen demand (BOD) and total suspended solids (TSS). If a WWTP achieved the effluent concentrations typical of secondary treatment (e.g., 30 mg/L for BOD), then it was meeting effluent standards. Over time, the impact of point source discharges on the water quality of receiving bodies has become important, and there has been a corresponding evolution away from technology-based effluent limits toward water quality-based effluent limits (WQBEL). Common types of regulated pollutants for a WWTP have been expanded to include fecal coliform, oil and grease, organics (such as pesticides, solvents, polychlorinated biphenyls, and dioxins), metals, and nutrients (such as nitrogen and phosphorus). As a result, chemicals that affect water quality but may give no indication of WWTP performance, such as nutrients, metals, and ammonia, have been added to NPDES permits.

Besides setting effluent limits, NPDES permits outline both standard and site-specific compliance monitoring and reporting requirements for the discharger. Finally, they detail enforcement actions that will be taken when and if regulated facilities fail to comply with the provisions of their permits. EPA uses a variety of techniques to monitor compliance, including on-site inspections and review of data submitted by permittees.

EPA has developed specific NPDES programs designed to combat particular types of effluent discharge that are exacerbated as the result of wet weather conditions and associated runoff and high flows. In particular, the NPDES Stormwater Program establishes a two-phased approach to addressing stormwater discharges. Phase I, which is currently being implemented, requires permits for separate stormwater systems serving medium-and large-sized communities (those with over 100,000 inhabitants) and for stormwater discharges associated with

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

industrial and construction activity involving at least five acres. There are currently three SPDES-permitted stormwater discharges associated with construction activities in the Catskill/Delaware watershed. Phase II, which is currently under development, will address remaining stormwater discharges. The goal of this program is to encompass as many activities and areas as possible, including urban areas with populations under 100,000, smaller construction sites, and retail, commercial, and residential activities.

Wetlands

Section 404 of the CWA establishes a program to regulate the discharge of dredged and fill material into the waters of the United States, which have been defined to encompass wetlands. Activities that are regulated under this program include water resource projects such as dams, infrastructure development such as highways, fill for development such as housing subdivisions, and conversion of wetlands to uplands for farming and forestry. The guiding principle of the program is that if a practical alternative that is less damaging to the aquatic environment exists or if the nation's waters would be significantly degraded, a proposed discharge of dredged or fill material into a wetland cannot be permitted. The U.S. Army Corps of Engineers administers the program within a policy framework established by EPA. Individual permits are usually required for activities with potentially significant impacts. As a means of expediting program administration, general permits governing particular categories of activities such as minor road crossings and utility line backfill are issued on a nationwide, regional, or state basis.

Antidegradation

Antidegradation is a federal regulation related to the CWA stating that waters must not be allowed to degrade in quality such that their use classification and water quality criteria are violated (CFR Part 131, 1983). The concept of antidegradation deals primarily with ''assimilative capacity"—the amount of additional pollution that a body of water can receive without exceeding its water quality criteria or use classification. Antidegradation policies are meant to be developed by each state and must contain language similar to that promulgated by EPA. Although not always achieved, one goal of the EPA policy is to describe how the state will allocate the assimilative capacity of its waters (R. Shippen, EPA, personal communication, 1998).

After a state has established use classifications and water quality criteria, it must develop an antidegradation policy that distinguishes three levels of water quality: Tier 1 (the lowest level of quality), Tier 2 (fishable and swimmable waters - High Quality Waters), and Tier 3 (Outstanding Natural Resources). Tier 1 waters cannot be allowed to degrade any further, and all existing uses of all

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

waters must be maintained. This is meant to guarantee a baseline level of protection for all waters, especially those that have no additional assimilative capacity. Tier 2 waters have a water quality greater than or equal to fishable/swimmable quality (i.e., they have some assimilative capacity). Water quality in these waters is only allowed to degrade to the level of fishable/swimmable (never lower) and only if certain significant criteria are met: (1) there must be important social or economic reasons for the lowering of water quality, (2) the public must be informed prior to any activity, and (3) the highest level of statutory and regulatory requirements for point sources, and the use of best management practices for nonpoint sources, must be achieved. Tier 3 waters, which have exceptional recreational and ecological significance (and consequently considerable assimilative capacity), cannot be allowed to degrade at all. These waters are generally found in national parks or other areas designated as pristine.

As one might expect, Tier 2 waters are the most controversial because a lowering of water quality may in some cases be allowed, using up some of the waters' assimilative capacity. EPA requires that any activities that will result in a lowering of Tier 2 water quality be reviewed to determine whether the activity will violate state antidegradation policy. How this review will be conducted, and which activities will trigger a review, is left to the states to decide.

Enforcement Authority

As with the SDWA, the CWA calls for state enforcement of the regulations issued by EPA. Having been granted primacy by EPA, the New York State Department of Environmental Conservation (NYS DEC) must ensure New York's compliance with the CWA. NYS DEC determines the use classifications and water quality criteria for all state waters, it oversees the TMDL program, it operates the SPDES permitting program for WWTPs, and it is responsible for developing and implementing the state antidegradation policy. Guidelines and policies for implementing the CWA have been written into New York State law (Article 17 of the Environmental Conservation Law).

LOCAL ENVIRONMENTAL REGULATIONS AFFECTING NEW YORK CITY

The SDWA and the CWA, while comprehensive, are not expected to provide the sole protection of surface and groundwater supplies used as sources of drinking water. Rather, they are meant to serve as minimum requirements with which the states must comply in creating their own environmental programs. All states have written environmental laws to interpret the federal statutes and have created additional requirements as well. These state laws, regulations, and policies fill gaps between the federal regulations and (in some cases) increase the level of protection afforded to bodies of water.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

Gaps between the federal regulations often stem from the various, sometimes-unrelated targets of these laws. For example, the SDWA lists specific quantitative standards for many known pollutants in drinking water, while the CWA mandates similar standards for source waters. Although both acts have watershed-based components, neither act requires or outlines a truly comprehensive watershed management strategy. The New York City MOA is an example of a state/local effort to design a watershed management strategy that complements and enhances federal environmental regulations.

New York City Watershed Memorandum of Agreement

The most extensive legal document governing activities in the New York City water supply watersheds is the 1997 New York City Watershed MOA. As described in Chapter 1, many sections of the MOA satisfy conditions of the City's filtration avoidance determination and are thus necessary for New York City to comply with the SWTR.

Contents of the Memorandum of Agreement

Land Acquisition Program. Because only 26 percent of Catskill/Delaware watershed is owned by New York City or New York State, an important element of the MOA is a land acquisition program that aims to increase the percentage of publicly owned land. This voluntary program allows New York City to acquire fee titles or conservation easements to vacant water quality-sensitive watershed lands on a "willing buyer/willing seller" basis. All titles and conservation easements are held in perpetuity. New York City has committed more than $250 million for land acquisition, and the MOA requires that New York City solicit participation of the owners of more than 3,50,000 acres by the year 2007. As discussed and analyzed in more detail in Chapter 7, areas closer to reservoir intakes and the distribution system are given higher priority for acquisition. The MOA also created a $17.5 million land acquisition program for the Croton watershed, but different criteria are used to prioritize the subwatershed areas, and there are no solicitation goals.

Watershed Rules and Regulations. Because most of the watershed is in private ownership, the Watershed Rules and Regulations were created to control activities within the watershed that may increase pollution. Both point and nonpoint pollution sources are targeted, including WWTPs, on-site sewage treatment and disposal systems (OSTDS), stormwater runoff, and storage of hazardous materials. The regulations contain minimum treatment requirements for technologies that control these sources of pollution and specify effluent standards that some of these treatment technologies must meet.

In addition, the regulations restrict a variety of activities from occurring in

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

close proximity to watercourses, reservoirs, reservoir stems, controlled lakes, and wetlands. For example, the siting of WWTPs, OSTDS, storage facilities for hazardous materials, petroleum, and salt, and the construction of impervious surfaces are all restricted within "setback" distances from the major bodies of water. There are some exemptions to these restrictions that were designed to promote responsible growth in existing areas while protecting water quality via increased regulation.

Watershed Protection and Partnership Programs. The purpose of the Watershed Protection and Partnership Programs is to preserve the economic and social character of the Catskill/Delaware watershed communities while maintaining and enhancing water quality. The Catskill Watershed Corporation (CWC), a not-for-profit corporation, was formed to manage some of these programs for the Catskill/Delaware watershed region. The MOA calls for about $240 million to be allocated for these efforts, which include infrastructure improvements for stormwater and wastewater, development, conservation, and education (see Chapter 7).

The MOA also provides funds (approximately $68 million) for Westchester and Putnam counties to develop and implement a Croton Plan. The objective of this plan is to develop a comprehensive approach to identify significant sources of pollution, to recommend measures for improving water quality, and to protect the character of watershed communities east of the Hudson River.

In addition to the Watershed Protection and Partnership Programs, the MOA established the Watershed Protection and Partnership Council to provide broad oversight of New York City watershed management. The 27-member Council consists of representatives from New York City and State government agencies, watershed counties, environmental groups, the CWC, EPA, and the Watershed Agricultural Council. Its three main functions are (1) to serve as "a forum for the exchange of views, concerns, ideas, information, and [non-binding] recommendations relating to Watershed protection and environmentally responsible economic development," (2) to "periodically review and address efforts undertaken by governments and private parties to protect the Watershed," and (3) to "solicit input from governmental agencies, private organizations, or persons with an interest in the Watershed and the New York City drinking water supply'' (MOA, Article IV). The Executive Committee of the Council, consisting of 16 members, has more specific functions.

Regulatory Authorities Involved in MOA Implementation

EPA, the New York State Department of Environmental Conservation (NYS DEC), and the New York State Department of Health (NYS DOH) are the regulatory agencies responsible for enforcing the provisions of the MOA. In particular, EPA Region 2 and NYS DOH oversee the New York City filtration

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

avoidance determination, while NYS DEC oversees the TMDL and the SPDES permitting programs. The efforts of these three agencies are focused almost exclusively on the New York City Department of Environmental Protection (NYC DEP), which implements these programs in the New York City watersheds. NYC DEP monitors the major bodies of water, inspects WWTPs, and runs a variety of nonpoint source control programs. Because of its predominant role in the watershed, NYC DEP is the primary focus of this report's reviews, critiques, and recommendations.

Other government agencies also play a role during implementation of the MOA. The New York State Department of State, Division of Local Government, provides training and technical assistance to local governments and community organizations to help them take advantage of the Watershed Protection and Partnership Programs. A local office has been established in the Catskills to increase access to watershed governmental officials and citizens. New York City operates a Department of Health (NYC DOH) that is responsible for safeguarding the health of city-dwellers. As part of its many responsibilities under the filtration avoidance determination, NYC DOH monitors waterborne disease occurrence in the City by a variety of methods discussed in Chapter 6. NYC DOH and NYC DEP work together to determine the prevalence of waterborne disease and its possible sources in the watershed, the water supply system, or the distribution system. Finally, county health departments are involved in ensuring the success of the MOA. Along with NYS DOH and NYC DEP, county health departments oversee the construction and maintenance of new sewerage and septic systems. This includes new residential septic systems and commercial, institutional, and multifamily systems up to a maximum flow of 10,000 gallons per day.

Other State and Local Laws

Several state and local laws complement the regulations found in the MOA, the CWA, and the SDWA. The most important of these is the New York State Environmental Quality Review Act of 1975 (SEQR, Article 8 of the Environmental Conservation Law). Similar to the National Environmental Policy Act of 1975, SEQR requires that an environmental impact statement (EIS) be written for all major ministerial actions. For example, an EIS was prepared in 1993 following the drafting of the New York City Watershed Rules and Regulations (NYC DEP, 1993).

Because of their size and scope, many of the actions required by and allowed under the MOA will require the preparation of an EIS. This process enables some public involvement in decision-making, but it also increases the time required for planning and implementation of new projects. Few states have a strong environmental review statute, and SEQR represents an extremely progressive environmental policy on the part of New York. Its provisions are described in greater detail in Box 3-5.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

BOX 3-5
State Environmental Quality Review (SEQR) Act

The purpose of the New York State Environmental Quality Review Act (as regulated in 6 NYCRR Part 617) is "to incorporate the consideration of environmental factors into planning, review, and decision-making processes of state, regional, and local government agencies at the earliest possible time." SEQR requires that all agencies determine whether the actions they undertake, fund, or approve of will have a significant impact on the environment. If so, an environmental impact statement (EIS) must be prepared that systematically considers significant adverse environmental impacts, alternatives, and mitigation. The EIS must also describe the potential social and economic benefits associated with the proposed project.

SEQR spells out a number of Type I actions that are likely to require the preparation of an EIS. These include changes in any zoning district affecting 25 acres or more, nonresidential projects physically altering 10 or more acres of land, and the acquisition, sale, lease, annexation, or transfer of 100 acres or more by a local agency. Examples with particular relevance to water quality include the construction of a WWTP or a large residential housing unit. Type II actions, which are likely to not require the preparation of an EIS, include repaving existing highways, maintaining existing landscaping, constructing a single-family home, adding a carport or swimming pool, and public or private forestry best management practices on less than 10 acres of land.

The process for developing an EIS is similar to that of the National Environmental Policy Act process. First, the proposed action is classified and an environmental assessment form is completed. The lead agency (usually NYS DEC) then decides if the action includes the potential for at least one significant adverse environmental impact, which will cause "substantial adverse change in existing air quality, ground or surface water quality or quantity, traffic and noise levels; a substantial increase in solid waste production, or a substantial increase in the potential for erosion, flooding, leaking, or drainage problems." Significant impacts also include removal of vegetation, interference with wildlife migration, creation of a conflict with a community's current plans or goals, creation of human health hazard, and substantial change in land use or intensity of land use. If there is no potentially significant impact, than a negative declaration is published and filed. For projects that may negatively affect the environment, the applicant must complete a draft EIS.

The draft EIS fully describes the proposed action, including its relevant social and economic benefits. The environmental setting is described,

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

and all potential environmental impacts are analyzed. In justifying the necessity for the action, the draft EIS must describe all reasonable alternatives to the action, including the "no-action" alternative. Finally, ways to reduce adverse environmental impacts must be explored. The draft EIS is a public document that must be available for a 30-day public review and comment period. After receiving and appropriately responding to public comments, the draft EIS is finalized. The project is then approved or denied by all relevant government agencies, ending the SEQR process.

Other important state laws pertaining to watershed management can be found elsewhere in New York's Environmental Conservation Law (ECL). With regard to wetlands, a permit is required for any construction, dredging, or dumping in a freshwater wetland (ECL § 24-0701). Fishing, hunting, and trapping are allowed without permit in tidal wetlands, as is farming in freshwater wetlands.

Finally, local government laws can play a role in watershed management, primarily via zoning provisions within the counties, towns, and villages of the watershed region. The Croton watershed contains portions of three counties—Westchester, Putnam, and Dutchess counties—while the Catskill/Delaware watershed wholly or partially includes Delaware, Schoharie, Greene, Sullivan, and Ulster counties. The role of local government regulations in dictating activities within the watershed region is described more extensively in Chapter 7.

REFERENCES

American Public Health Association. 1995. Standard Methods for the Examination of Water and Wastewater . 19th Edition. Washington, DC: American Public Health Association.

American Water Works Association (AWWA). 1993. Consumer Attitude Survey on Water Quality Issues. Denver, CO: American Water Works Association.

Arizona Department of Environmental Quality. 1996. R18-11-1 Appendix A Numeric Water Quality Standards. April, 1996.


Baker, M. N. 1949. The Quest for Pure Water. New York: American Water Works Association.

Bellar, T. A., and J. J. Lichtenberg. 1974. Determining volatile organics at microgram-per-litre levels by gas chromatography. Journal of the American Water Works Association 66(12):739–744.

Borchardt, J. A., and G. Walton. 1971. Water quality. In: Water Quality and Treatment, American Water Works Association. 3rd ed. New York, NY: McGraw-Hill.

Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

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×

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Suggested Citation:"3 Evolution of Key Environmental Laws, Regulations, and Policies." National Research Council. 2000. Watershed Management for Potable Water Supply: Assessing the New York City Strategy. Washington, DC: The National Academies Press. doi: 10.17226/9677.
×

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In 1997, New York City adopted a mammoth watershed agreement to protect its drinking water and avoid filtration of its large upstate surface water supply. Shortly thereafter, the NRC began an analysis of the agreement's scientific validity.

The resulting book finds New York City's watershed agreement to be a good template for proactive watershed management that, if properly implemented, will maintain high water quality. However, it cautions that the agreement is not a guarantee of permanent filtration avoidance because of changing regulations, uncertainties regarding pollution sources, advances in treatment technologies, and natural variations in watershed conditions.

The book recommends that New York City place its highest priority on pathogenic microorganisms in the watershed and direct its resources toward improving methods for detecting pathogens, understanding pathogen transport and fate, and demonstrating that best management practices will remove pathogens. Other recommendations, which are broadly applicable to surface water supplies across the country, target buffer zones, stormwater management, water quality monitoring, and effluent trading.

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