United States
Environmental Protection (43051
Agency
Office of Water
EPA-823-D-00-001
January 2000
DRAFT
Implementation Guidance for
Ambient Water Quality
Criteria for Bacteria - 1986
U.S. EPA Headquarters Library
Mai' code 3201
1200 Pennsylvania Avenue NW
Washington DC 20460
EPA
823-
D-
00-001
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacfer/a--1986
Executive Summary
p. 2
This guidance was developed to assist States, Territories, and authorized Tribes
implement EPA's recommended water quality criteria for bacteria. EPA recommended E. colt or
enterococci for freshwaters and enterococci for marine waters in its Ambient Water Quality
Criteria for Bacteria~l9$6. Despite these recommendations, many States, Territories, and
authorized Tribes continue to use fecal or total coliforms to protect human health from the risk of
gastrointestinal illness in primary contact recreation designated waterbodies.
States, Territories, and authorized Tribes have identified several issues that are impeding
their adoption of E. colt and/or enterococci as water quality criteria for bacteria. Many of these
issues are addressed in this guidance, including a reaffirmation of the scientific validity of EPA's
1986 water quality criteria for bacteria, recommendations for how States, Territories, and
authorized Tribes may make the transition from fecal coliforms to E. co/z"/enterococci,
application of EPA's recommended water quality criteria to waterbodies contaminated by non-
human sources, application of EPA's recommended water quality criteria in tropical
environments and recommendations of appropriate water quality criteria for bacteria for
waterbodies that are designated for non-primary contact uses.
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria-1986
p. 3
Contents
1.0 Background and Introduction 4
1.1 What is the purpose of this guidance? 4
1.2 Why is EPA publishing this guidance? 5
1.3 Who should use this guidance? 6
1.4 What is the basis for EPA's 1986 water quality criteria for bacteria? 6
2.0 Reaffirmation of scientific validity of EPA's Ambient Water Quality Criteria for
Bacteria - 1986 7
2.1 Does EPA still support its Ambient Water Quality Criteria for Bacteria- 1986? 7
2.2 What was the design of the studies used to develop EPA's recommended water quality
criteria? 8
2.3 What epidemiological studies on swimming-associated health effects and the quality of
recreation water have been conducted since EPA published its recommended 1986 water
quality criteria for bacteria? 9
2.4 Have subsequent studies affected EPA's recommended water quality criteria for
bacteria? 13
3.0 Relationship between water quality standards and beach monitoring and advisory programs . 18
4.0 Implementation of EPA's Ambient Water Quality Criteria for Bacteria - 1986 20
4.1 What is EPA's recommended approach for States making the transition from fecal
coliforms to E. coli and/or enterococci? 20
4.2 How should EPA's recommended water quality criteria be implemented in regulatory
programs? 20
4.3 How should EPA's recommended water quality criteria be applied for recreational
waters in tropical climates? 26
4.4 Stream Flow (reserved) 27
4.5 Application of water quality criteria for bacteria in high flows (reserved) 27
4.6 Development and adoption of site-specific water quality criteria (reserved) 28
5.0 Managing human health risk in non-primary contact recreation waters 29
5.1 Where should the primary contact recreation use and EPA's recommended water quality
criteria apply? 29
5.2 When is it appropriate to designate recreation uses other than primary contact
recreation? 30
5.3 What information should be contained in a use attainability analysis to adopt
subcategories of a primary contact recreation use or to remove a primary contact
recreation use? 31
5.4 What water quality criteria should be applied to waters where primary contact recreation
is not occurring? 32
5.5 Will EPA publish risk-based water quality criteria to protect for "secondary contact"
uses? 33
6.0 Identification of current and future activities 34
6.1 When will EPA propose and promulgate 24-hour methods? 34
6.2 When will EPA develop a laboratory techniques video? 34
6.3 What will be addressed in the upcoming National Guidance for Recreational Beach
Managers and when will it be published? 35
6.4 What will be addressed in the upcoming Implementation of the Water Quality-Based
Provisions in the CSO Control Policy and when will it be published? 35
6.5 What will be addressed in the upcoming Assessment Methodology Guidance and when
will it be published? 35
References 36
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria1986
p. 4
1.0 Background and Introduction
Water quality criteria for bacteria are concentrations of indicator organisms that should
not be exceeded in order to protect human health from pathogen-caused illness. These indicator
organisms often do not cause illness directly, but have demonstrated characteristics that make
them good predictors of harmful pathogens in waterbodies. Pathogens are disease-causing
microorganisms that include viruses, protozoa, and bacteria.
Many of these pathogens can not be measured directly. In addition, waterbodies may
contain many different pathogens, making measurement and enumeration impractical, even if
techniques were available to detect all pathogens of concern. Therefore, indicator organisms are
used to predict the health risks from pathogens residing in waterbodies. The U. S.
Environmental Protection Agency (EPA) conducted studies u demonstrating that for fresh water,
Escherichia coli (E. Coli) and enterococci are best suited for predicting the presence of
gastrointestinal illness-causing pathogens in freshwater and for marine waters, enterococci is best
suited. EPA published its recommendations in Ambient Water Quality Criteria for
Bacteria-1986.3
1.1 What is the purpose of this guidance?
This guidance provides recommendations to help States, Territories, and authorized
Tribes" implement EPA's recommended water quality criteria for bacteria. EPA strongly
encourages States" that have not already done so, to adopt the recommendations set forth in
Ambient Water Quality Criteria for Bacteria - 1986 or other water quality criteria for bacteria
based on scientifically defensible methods into their water quality standards to replace water
quality criteria for total or fecal coliforms. EPA's 1986 water quality criteria for bacteria
recommend the use of enterococci for marine waters and E. coli or enterococci for fresh waters.
As indicated in EPA's Office of Water Guidance to States, Tribes, and Regions on Priorities for
the Water Quality Standards Program for FY 2000-2002, the transition to E. coli and enterococci
bacterial indicators is an Agency priority for the triennial review of water quality standards
occurring in FY2000-2002. EPA encourages States to take these steps during their upcoming
triennial reviews. If a State, Territory, or authorized Tribe does not adopt EPA's recommended
1986 bacteria water quality criteria during this period, EPA intends to act under section
303(c)(4)(B) of the Clean Water Act (CWA) to promulgate federal water quality standards, with
the goal of assuring that EPA's recommended 1986 bacteria water quality criteria apply in all
States, Territories, and authorized Tribes, as appropriate, by 2003.
U.S. EPA Headquarters Library
Mail code 3201
1200 Pennsylvania Avenue NW
Washington DC 20460
"Pursuant to section 518{e) of the CWA, EPA is authorized to treat an Indian Tribe in the same manner as a
State for the purposes of administering a water quality standards program. 40 CFR 131.8 establishes the criteria by
which the Agency makes such a determination. At this time, 21 tribes have requested and been granted
authorization for treatment as a State, and 14 Tribes have adopted water quality standards pursuant to section 303(c)
of the Act, and the implementing federal regulations at 40 CFR 131.
"Note: The term "States" will be used to denote States, Territories, and authorized Tribes.
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria-1986
p. 5
1.2 Why is EPA publishing this guidance?
Despite EPA's and other studies (see section 2.0) demonstrating better correlation
between swimming-associated illnesses and E. coli and enterococci counts, many States continue
to use either fecal or total coliform water quality criteria to protect and maintain designated uses.
As of April 1999, only 16 States, two Territories, and two Tribes had adopted EPA's
recommended water quality criteria for E. coli and/or enterococci to protect designated
recreational waters. EPA recognizes there has been some uncertainty among States with regard
to how EPA's recommended 1986 bacteria water quality criteria should be implemented and how
the transition should be made from fecal coliforms to E. coli and enterococci. This guidance
addresses those issues identified by States as impeding their progress toward adopting and
implementing EPA's current recommended water quality criteria for bacteria.
In March 1999, EPA released its Action Plan for Beaches and Recreational Waters
(Beach Action Plan). In the Beach Action Plan, the Agency acknowledges the need to move to
E. coli and enterococci and commits EPA's Office of Water to developing a policy to facilitate
State adoption of the recommended water quality criteria. This guidance carries out that
commitment and continues to strongly encourage States to adopt the 1986 water quality criteria
for bacteria during their next triennial reviews. To assist States in the adoption and
implementation of EPA's recommended water quality criteria for bacteria, this document
addresses the following:
A reaffirmation of the scientific validity of the Ambient Water Quality Criteria for
Bacteria 1986 through a review of relevant peer-reviewed studies conducted since
EPA's 1984 epidemiological studies;
Explanation of the relationship between water quality standards and beach monitoring
and advisory programs;
Recommendations for making the transition from fecal coliforms to EPA's recommended
water quality criteria, including the use of multiple indicators during a transition period;
Implementation of EPA's recommended water quality criteria in water quality regulatory
programs;
Application of EPA's recommended water quality criteria to waters contaminated by non-
human sources;
Appropriate approaches for monitoring the safety of recreational waters in those tropical
climates where E. coli and enterococci may exist naturally in the soil environment,
possibly complicating the use of those organisms as indicators;
Appropriate approaches for managing risk in non-primary contact recreational waters,
including the use of alternate illness rates and site-specific water quality criteria;
Current and future activities: projected schedule for proposed promulgation of methods
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DRAFT Implementation Guidance for Ambient Water Quality Criteria forfiacfena-1986
p. 6
into 40 CFR 136, announcement of a training video, drafts of the National Guidance for
Recreational Beach Managers and the Implementation of the Water Quality-Based
Provisions in the CSO Control Policy, and the schedule for the release of the Assessment
Methodology Guidance.
1.3 Who should use this guidance?
This guidance should be used by State, Territory, and authorized Tribal environmental
agencies administering a water quality standards program.
1.4 What is the basis for EPA's 1986 water quality' criteria for bacteria?
In 1986, EPA published Ambient Water Quality for Bacteria -1986. The water quality
criteria recommend bacterial geometric mean densities not to be exceeded in marine and fresh
recreational waters and provide a scientific rationale for developing water quality standards to
maintain the safety of waters used as recreational resources. The data supporting the water
quality criteria were obtained from a series of research studies conducted by EPA examining the
relationship between swimming-associated illness and the microbiological quality of the waters
used by recreational bathers.1-2
The results of those studies demonstrated that fecal coliforms, the indicator originally
recommended in 1968 by the Federal Water Pollution Control Administration of the Department
of the Interior, showed less correlation to swimming-associated gastroenteritis than some other
indicator organisms. Two indicator organisms, E. coli and enterococci, showed a strong
correlation, the former in fresh waters only and the latter in both fresh and marine waters. The
strong correlation may be a result of the survivability of the indicator organisms in the
environment being similar to the survivability of the pathogens of concern. Regrowth of fecal
coliforms under certain environmental conditions has been problematic; the conditions necessary
for E. coli and enterococci to experience regrowth are within much narrower ranges than the
conditions suitable for the regrowth of fecal coliforms. Another factor favoring enterococci as an
indicator organism is its resistance to environmental factors, particularly saline environments,
enhancing its ability as a suitable indicator for marine waters.
Consequently, EPA's Ambient Water Quality Criteria for Bacteria -1986 recommended
the use of E. coli and enterococci rather than fecal coliforms. The recommended steady-state
geometric mean values of these water quality criteria for bacteria are 33 enterococci per 100
milliliters (ml) and 126 E. coli per 100 ml for fresh waters; and a geometric mean of 35
enterococci per 100 ml for marine waters. These values are based on specific levels of risk of
acute gastrointestinal illness. The levels of risk used by EPA correlating to these values are no
more than eight illnesses per 1,000 swimmers for fresh waters, and no more than 19 illnesses per
1,000 swimmers for marine waters. The illness rates are EPA's best estimates of the accepted
illness rates for areas that had previously applied the fecal coliform criterion. EPA has
determined that when implemented in a conservative manner, these water quality criteria are
protective of gastrointestinal illness resulting from primary contact recreation.
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for BacteriaI 986
p. 7
2.0 Reaffirmation of EPA's recommended water quality criteria
2.1 Does EPA still support its Ambient Water Quality Criteria for Bacteria - 1986?
EPA reviewed the original studies supporting its recommended 1986 water quality
criteria for bacteria and the literature on epidemiological studies conducted after EPA performed
its marine and freshwater studies of swimming-associated health effects. As a result of these
reviews, EPA continues to believe that when applied and implemented conservatively, EPA's
recommended water quality criteria for bacteria are more protective of human health for
gastrointestinal illness than fecal coli forms.
EPA believes that these water quality criteria must be applied and implemented
conservatively for several reasons. Alternative statistical models applied to the original studies
on which the water quality criteria are based suggest higher estimated illness rates for the same
recommended geometric means. In addition to the results of the statistical analyses, several other
factors also argue for the conservative application of water quality criteria for bacteria. New
pathogens and strains of antibiotic resistant bacteria capable of causing gastrointestinal illness
have evolved since EPA's studies were conducted. In addition, EPA's recommended water
quality criteria for bacteria are only intended to protect against gastrointestinal illness-causing
pathogens. Other pathogens may be present in a waterbody capable of causing eye, ear, nose,
and throat infections as well as skin rashes and respiratory illness. Also, as stated in Ambient
Water Quality Criteria for Bacteria-\986:
"...the major limitations of the criteria are that the observed relationship may not
be valid if the size of the population contributing the fecal wastes becomes too
small or if epidemic conditions are present in a community. In both cases the
pathogen to indicator ratio, which is approximately constant in a large population
becomes unpredictable and therefore, the criteria may not be reliable under these
circumstances."
To assure water quality criteria for bacteria are generally protective for gastrointestinal
illness, EPA recommends frequent monitoring of known bathing areas to establish a more
complete database upon which to determine if the waterbody is attaining the water quality
criteria; conservative use of mixing zones for bacteria where mixing zones are authorized;
prohibiting mixing zones from impacting known primary contact recreation areas; using the
appropriate single sample maximum in the assessment of primary contact recreation waterbodies;
and conducting a sanitary survey when higher than normal levels of bacteria are measured. A
sanitary survey is an examination of a watershed to determine if unauthorized sanitary discharges
are occurring from sources such as failed septic tank leach fields or cesspools, sewage leakage
from broken pipes, sanitary sewer overflows from hydraulically overloaded sewers, or overflows
from storm sewers that may contain illegal sanitary sewer connections. The survey should use
available public health and public works departments' records to identify where such septic tanks
and sewer lines exist so that observations are focused in the right places. A sanitary survey
might also use dyes or other tracers in both dry and wet weather to see if unauthorized discharges
are occurring from septic tanks and sewers. In addition, EPA recommends that sanitary surveys
identify other possible sources, including confined animal areas, wildlife watering points, and
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria-1986
p. 8
recreational spots, such as dog running/walking areas, since these are also sources of fecal
pollution. EPA also reiterates that States may adopt more stringent water quality criteria to
address these concerns.
In addition to its review of the original studies, EPA reviewed the literature on
epidemiological studies conducted after EPA performed its marine and freshwater studies of
swimming-associated health effects. The review examined recent data to determine if EPA's
findings were supported or if different indicator bacteria were consistently shown to have
quantitatively better predictive abilities. EPA's Office of Research and Development (ORD)
reviewed 11 separate peer-reviewed studies. This detailed review is contained in the following
paragraphs. Upon this review, ORD concluded:
The epidemiological studies conducted since 1984, which examined the
relationships between water quality and swimming-associated health effects, have
not established any new or unique principles that might significantly affect the
current guidance EPA recommends for maintaining the microbiological safety of
marine and freshwater bathing beaches. Many of the studies have, in fact,
confirmed and validated the findings of the U.S. EPA studies. There would
appear to be no good reason for modifying the Agency's current guidance for
recreational waters at this time.
As a result of this examination, EPA believes its 1986 water quality criteria for bacteria continue
to represent the best available science and serve as a defensible foundation for protecting public
health in recreational waters. EPA finds no reason to undertake a revision of the water quality
criteria at this time. EPA continues to believe that when applied and implemented conservatively,
EPA's recommended Ambient Water Quality Criteria for Bacteria-1986 are fully protective of
human health for gastrointestinal illness.
2.2 What was the design of the studies used to develop EPA's recommended
water quality criteria?
In 1986, EPA published its recommended ambient water quality criteria for bacteria for
marine and fresh recreational waters. The water quality criteria provide a scientific rationale for
States, Territories, and authorized Tribes to use as guidance in adopting water quality standards
to maintain the safety of waters used as recreational resources. The data supporting the water
quality criteria were obtained from a series of research studies1'2 conducted by EPA examining
the relationships between swimming-associated illness and the microbiological quality of waters
used by recreational bathers. Some of the salient features of the design of the research studies
are described below and will be referred to in later parts of the review. The EPA design for
beach studies has been used in many subsequent studies of swimming-associated health effects
and water quality in other countries.
The EPA studies were unique at the time they were initiated because they attempted to
relate swimmer illness to water quality at the time of swimming. This was done by approaching
individuals as they were leaving the beach and asking if they would volunteer to be a part of the
bathing beach studies. Individuals that had been swimming in the previous week were not made
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DRAFT Implementation Guidance fcr Ambient Water Quality Criteria for Bacter/a-1986
p. 9
part of the study. After seven to 10 days, the volunteers were contacted by telephone to
determine their health status since the swimming event. Control non-swimmers, usually a
member of the volunteer's family, were questioned in a similar manner. The water quality was
measured on the day the volunteers swam. Multiple potential indicators were measured in each
beach water sample. Multiple indicators were measured because it was unknown which one
would best correlate to swimmer illness. The swimming-associated illness parameter was
obtained by subtracting the non-swimmer illness rate from the swimmer illness rate using data
collected over a summer trial. In those studies reported here using this design, it will state that
the EPA design was used rather than describing it in detail each time.
2.3 What epidemiological studies on swimming-associated health effects and the
quality of recreation water have been conducted since EPA published its
recommended 1986 water quality criteria for bacteria?
A recent review by Pruss4 of all studies since 1953 that examined the relationship
between swimming-associated gastroenteritis and water quality, pointed out that nine separate
marine studies and at least two fresh water studies had been conducted since the EPA studies
were completed in 1984. In this review, each of those studies is summarized with regard to the
size of the study, the study design, the water quality indicator bacteria measured, and the results
of the study with respect to gastrointestinal illness. Some of the studies looked only at whether
an association existed between swimming and illness at a polluted beach or a non-polluted beach,
while other studies attempted to determine the relationship between increasing levels of poor
water quality and the levels of gastrointestinal illness associated with those increases. This
review does not address studies that examined non-enteric illnesses or infections unrelated to
gastrointestinal disease. The intent of the review is to carefully examine all of the studies
conducted subsequent to the EPA studies and to determine if they have a significant impact on
the current water quality criteria for bacteria recommended by the Agency.
Marine Studies
In 1987, Fattal et of reported on a study of health and swimming conducted at beaches
near Tel-Aviv, Israel. The study design was the same as the one used by EPA. Beach water
quality was measured using fecal coliforms, enterococci, and E. coli. Three beaches with
different water qualities were studied. Symptoms among bathers were analyzed according to
high and low categories of bacterial indicator densities in the seawater. The high and low
categories for fecal coliforms were above and below 50 colony forming units (cfu) per 100 ml.
The limits for enterococci and E. coli were 24 cfu per 100 ml. Excess illness was observed only
in swimmers 0-4 years old at low categories of the indicators. Significant differences in illness
rates between swimmers and non-swimmers occurred only at high indicator densities.
Enterococci were the most predictive indicator for enteric disease symptoms.
In 1990, Cheung and his co-workers6 reported on a health effects study related to beach
water pollution in Hong Kong. The basic EPA design was used in conducting this investigation.
Nine microbial indicators were examined as potentially useful measures of water quality. They
included fecal coliforms, E. coli, Klebsiella spp, fecal streptococci, enterococci, staphylococci,
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DRAFT Implementation Guidance for Ambient WaterQuality Criteria for Sacteria-1986
p. 10
Pseudomonas aeruginosa, Candida albicans, and total fungi. The study was carried out at nine
beaches that were polluted either by human sewage discharged from a submarine outfall or
carried by storm water drains running into the beaches. Two of the beaches were contaminated
mainly by livestock wastes. Approximately nineteen thousand usable responses were obtained,
of which about 77% were from swimmers. The enterococci densities at the beaches ranged from
31 to 248 cfii per 100 ml. The range for E. coli was from 69 to 1714 cfu per 100 ml. The overall
gastrointestinal illness rates were significantly higher in swimmers than in non-swimmers.
Children under 10 years old were more likely to exhibit gastrointestinal illness (GI) and highly
credible gastrointestinal illness (HCGI) symptoms than individuals older than 10 years. The best
relationship between a microbial indicator density and swimming-associated health effects was
between E. coli and HCGI.
Health risks associated with bathing in sea water in the United Kingdom were described
by Balarajan et al.1 in 1991. This study used the EPA design for these trials. The reported study
was conducted at one beach where 1,883 individuals participated, 1,044 bathers and 839 non-
bathers. The methods used to measure water quality were not given. Ratios of illness in
swimmers to non-swimmers were developed. The rate of gastrointestinal illness was found to be
significantly greater in bathers than in non-bathers. The risk of illness increased with the degree
of exposure, rising from 1.25 in waders, 1.31 in swimmers, and 1.81 in surfers or divers. The
authors concluded that the increase was indicative of a dose-response relationship.
Von Schimding and co-workers8 conducted a study to determine the relationship between
swimming-associated illness and the quality of bathing beach waters. A series of discrete,
prospective trials was carried out at a relatively clean and a moderately polluted beach following
the methodology used in the EPA studies. The beaches were situated on the Atlantic coast of
South Africa. The moderately polluted beach was affected by septic tank overflows, storm water
run-off, and feces-contaminated river water. A number of potential indicator organisms were
measured including enterococci, fecal coliforms, coliphages, staphylococci, and F-male-specific
bacteriophages. A total of 1,024 people were contacted, of whom 733 comprised the final study
population. The moderately polluted beach was characterized by fecal coliforms and
enterococci. The median fecal coliform density was 77 cfu per 100 ml and the median
enterococci density was 52 cfu per 100 ml. The median fecal coliform and enterococci densities
at the relatively clean beach were 8 and 2 cfu per 100 ml, respectively. The rates for
gastrointestinal symptoms were appreciably higher for swimmers than non-swimmers at the
more polluted beach than at the less polluted beach, but the differences were not statistically
significant, either for children less than ten years of age or for adults. The lack of statistical
significance may have been due in part to the uncertain sources of fecal contamination.
In 1993, Corbett et al.9 conducted a study to determine the health risks of swimming at
ocean beaches in Sydney, Australia. The study used a design slightly modified from the EPA
approach. First, no one under the age of 15 was recruited for the study and, second, multiple
samples were taken at the time of swimming activity. The inclusion of families and social
groups was minimized. Water quality was measured using fecal coliforms and fecal streptococci.
A total of 2,869 individuals participated in the study. Of this group, 32.2% reported that they did
not swim. In general, gastrointestinal symptoms in swimmers did not increase with increasing
counts of fecal bacteria. However, fecal streptococci were worse predictors of swimming-
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria-1986
p. 11
associated illness than fecal coliforms. Although no relationship was observed between the
measured indicators and gastrointestinal illness, swimmers who swam for more than 30 minutes
were 4.6 times more likely to develop gastrointestinal symptoms than were those that swam for
less than 30 minutes. The lack of a relationship between increasing fecal coliform densities and
gastrointestinal symptoms was similar to results noted in the EPA marine and freshwater studies
where increasing illness rates were not associated with increasing fecal coliform densities.
In 1994, Kay et al.I0 conducted a series of four trials at bathing beaches in the United
Kingdom to examine the relationship between swimming-associated illness and water quality.
The design of this study differed from previous studies in that the study population was selected
prior to each trial. On the trial date, half of the participants were randomly assigned to be
swimmers, with the remaining participants being non-swimmers. Each swimmer swam in a
designated area that was monitored by taking a sample every 30 minutes. Samples were
analyzed for total and fecal coliforms, fecal streptococci, Pseudomonas aeruginosa, and total
staphylococci. The total number of participants in the study was 1,112, of which 46% were
selected as swimmers. All of the study volunteers were older than 18 years of age. Analysis of
the data indicated that the rates of gastroenteritis were significantly higher in the swimming
group than in the non-swimming group. Only fecal streptococci showed a significant dose-
response relationship with gastroenteritis. The analysis suggested that the risk of gastroenteritis
did not increase until bathers were exposed to about 40 streptococci per 100 ml.
In 1995, Kueh et a/'1 reported a second study conducted at Hong Kong beaches. Only
two beaches were examined in the second study, rather than the nine beaches examined in the
1990 Hong Kong study. The study design for collecting health data was similar to that followed
in the EPA studies. The ages of study participants ranged from 10 to 49 years of age. Unlike the
EPA studies, follow-up telephone calls were made two days after the swimming event rather than
seven to 10 days. Another aspect of the Hong Kong study differing from the EPA studies was
the collection of clinical specimens from ill participants with their consent. Stool specimens
were analyzed for Rotavirus, Salmonella spp, Shigella spp, Vibrio spp, and Aeromonas spp.
Throat swabs were examined for Influenza A and B; Parainfluenza virus types 1,2 and 3;
Respiratory Syncytial Virus and Adenovirus. Water samples were examined for E. coli, fecal
coliforms, staphylococci, Aeromonas spp, Clostridium perfringens, Vibrio cholera, Vibrio
parahemolyticus. Vibrio vulnificus, Salmonella spp, and Shigella spp. A total of 18,122
individuals participated in the study. Although the levels of indicator densities were not reported
for the beaches, the gastrointestinal illness rates were significantly higher at the more polluted
beach. This study did not find a relationship between E. coli and swimming-associated illness as
had been found in the original Hong Kong study. This may have been, as pointed out by the
authors, due to the fact that only two beaches were examined rather than nine. The cause of the
infections could not be ascertained from the clinical specimens obtained from ill individuals.
In 1998, McBride et a/12 reported prospective epidemiological studies on the possible
health effects from sea bathing at seven New Zealand beaches. A total of 1,577 and 2,307 non-
swimmers participated in the studies. Although the EPA study design was used, it was slightly
modified in that follow-up interviews were conducted three to five days after the swimming
event rather than the seven to 10 days used in the U.S. studies. Fecal coliforms, E. coli, and
enterococci were used to measure water quality. The results of the study showed that enterococci
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacter/a-1986
p. 12
were most strongly and consistently associated with illness risk for the exposed groups. Risk
differences between swimmers and non-swimmers were significantly increased if swimmers
stayed in the water for more than 30 minutes as compared to those in the water less than 30
minutes. The risk differences were slightly greater for paddlers than for swimmers.
The most recent study of possible adverse health effects associated with swimming in
marine waters was conducted at beaches on Santa Monica Bay, California, by Haile and co-
workers.13 The objective of this study was to determine if excess swimming-associated illness
could be observed in swimmers exposed to waters receiving discharges from a storm drain. The
study design was patterned after the U.S. EPA studies. Water samples were taken at ankle depth
and collected from sites at the storm drain, 100 yards up-coast, and 100 yards down-coast.
Samples were also collected 400 yards up-coast or down-coast of the storm drain, depending on
which location would be used as a control area. The samples were analyzed for total coliforms,
fecal coliforms, enterococci, and E. coli. One sample was collected each Friday, Saturday, and
Sunday of the study at the mouth of the storm drain and analyzed for enteric viruses. Subjects of
all ages participated in the study. A total of 11,686 subjects volunteered to take part in the study.
The results of the study with regard to associations between bacterial indicators and health
outcomes were presented in terms of thresholds of bacterial densities, which were somewhat
arbitrarily chosen. No positive associations, as measured by risk ratios, were observed for E. coli
at bacterial density thresholds of 35 and 70 cfu per 100 ml. A less arbitrary analysis using a
continuous model showed more positive associations, especially for enterococci. The model for
enterococci indicated positive associations with fever, skin rash, nausea, diarrhea, stomach pain,
coughing, runny nose and highly credible gastrointestinal illness. The associations of symptoms
with indicators were very weak in the case of E. coli and fecal coliforms. The authors also found
that the total coliform to fecal coliform ratio was very informative. Using a ratio of 5.0 as a
threshold, diarrhea and highly credible gastrointestinal illness were associated with a lower total
coliform to fecal coliform ratio regardless of the absolute level of fecal coliforms. When their
analysis was restricted to subjects where the total coliforms exceeded 5000 cfu per 100 ml,
significantly higher risks were detected for most outcomes. One of the general conclusions of
the study was that excess gastrointestinal illness is associated with swimming in feces-polluted
bathing water.
Fresh Water Studies
In 1985, Seyfried et al.14 reported on a prospective epidemiological study of swimming-
associated illness in Canada. These investigations used the EPA methodology in carrying out the
study. Water quality was measured with the following bacterial indicators of swimming water
quality: fecal coliforms, fecal streptococci, heterotrophic bacteria, Pseudomonas aeruginosa and
total staphylococci. A total of 4,537 individuals participated in the study, of which 2,743 were
swimmers and 1,794 were non-swimmers. Swimmers were found to have significantly higher
gastrointestinal illness rates than non-swimmers, and swimmers under the age of 16 had
substantially higher rates than swimmers 16 and older. Logistic regression analysis was
performed to determine the best relationship between water quality indicators and swimming-
associated illness. A small degree of correlation was observed between fecal streptococci and
gastrointestinal illness. The best correlation was between gastrointestinal illness and
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria-1986
p. 13
staphylococcus densities.
In 1989, Ferley et a/15 described an epidemiological study conducted in France that
examined health effects associated with swimming in a freshwater river. A total of 5,737
individuals participated in the study. The quality of the water was measured by assaying for
fecal coliforms, fecal streptococci, and Pseudomonas aeruginosa. The study design for
collecting health data was unique. The maximum latency period for the illness category groups
examined in this study was three days. Illnesses occurring during the course of the study were
assigned to the nearest day within the latency period on which a sample was taken. A weighted
linear regression was performed to relate gastrointestinal morbidity incidence rates to different
levels of exposure to indicator bacteria. Significant excess gastrointestinal illness was observed
in swimmers. Furthermore, regression of gastrointestinal illness incidence to the concentration
of indicator organisms showed a good relationship between swimming-associated illness, and
both fecal coliforms and fecal streptococci. The strongest correlation with incidence rates of
acute gastrointestinal disease was to fecal streptococci densities. The authors indicate that what
they defined as fecal streptococci essentially included what the U.S. EPA studies call
enterococci.
2.4 Have subsequent studies affected EPA's recommended water quality criteria
for bacteria?
No. None of the studies examined by EPA in its review presented evidence that
necessitate revising the 1986 water quality criteria for bacteria recommended by EPA. Most of
the studies used a survey plan similar to that used by EPA in the Agency's studies during the
1970's and 1980's. The study sites chosen by most, if not all, of the investigators also were
similar to those studied by EPA. One site was usually a beach, with some fecal contamination,
and the other site was usually a relatively unpolluted beach. Most of the pollution sources to the
polluted beaches came from known point sources. The results from these studies were similar to
those found in the EPA studies, i.e., swimming in fecal contaminated water is associated with a
higher rate of gastrointestinal illnesses in swimmers when compared to non-swimmers. This
outcome was not observed in one or two of the studies. The reason for a negative finding is
unclear, but it could be related to factors such as the short length of time between the swimming
event and the follow-up contact, the lack of children in the study groups, or the selection of a
study site where the pollution source was poorly defined.
Only a limited number of studies attempted to show a dose-response relationship between
swimming water quality and gastrointestinal illness. Six of the studies6-10-12-14-15 showed that as
the level of pollution increased, there was also an increase in swimming-associated illness. Only
two studies that looked for a relationship between swimming-associated illness and the level of
water quality failed to find such a relationship.9-11 It is possible that these findings were related to
the indicator organisms measured, fecal coliforms and fecal streptococci, or to the methodology
used to detect the indicators. In general, the result of these studies was similar to the results
found in the EPA studies, i.e., the swimming-associated illness rate increased with the water
pollution levels.
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria-1986
p. 14
It has been shown that some organisms are superior to others for predicting
gastrointestinal illness in swimmers based on the density of the indicator organism in bathing
waters. In the EPA studies, E. coli and enterococci showed the strongest relationships to
swimming-associated gastrointestinal illness. Some of the studies reviewed describe other
microbes showing strong relationships to swimming-associated gastrointestinal illness, such as
staphylococci,14 Clostridium perfringens,n andAeromonasspp.]l Most of the studies, however,
had findings similar to those of the EPA studies where enterococci were shown to be the most
efficient indicator for measuring marine water quality. One of the two fresh water studies
indicated that E. coli and enterococci showed very strong relationships to swimming-associated
gastrointestinal illness. In general, the best indicator organisms for measuring water quality in
the reviewed studies were similar to those observed in the EPA studies (e.g., E. coli and
enterococci).
The EPA and other studies reviewed here mainly examine the relationships between
densities of indicator bacteria and gastrointestinal illness. EPA's recommended water quality
criteria for bacteria are for protection from gastrointestinal illness. Pathogens are also capable of
causing other health effects, including skin, eye, ear, nose, and throat infections, as well as skin
rashes and respiratory illness. As part of EPA's Beach Action Plan, EPA intends to investigate
the development of water quality criteria for other pathogens capable of causing other adverse
health effects.
The epidemiological studies conducted since 1984, examining the relationships between
water quality and swimming-associated gastrointestinal illness, have not established any new or
unique principles that might significantly affect the current water quality criteria EPA
recommends for protecting and maintaining recreation uses of marine and fresh waters. Many of
the studies have, in fact, confirmed and validated the findings of EPA's studies. Thus, EPA has
no new scientific information or data justifying a revision of the Agency's recommended 1986
water quality criteria for bacteria at this time.
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria1986
p. 18
3-0 Relationship between water quality standards and beach monitoring and advisory'
programs
Section 303 of the Clean Water Act (CWA or "the Act") directs States, with oversight by
EPA, to adopt water quality standards to protect the public health and welfare, enhance the
quality of water and serve the purposes of the CWA. Under section 303, States are required to
develop water quality standards for waters of the United States within the State. Section 303(c)
provides that water quality standards shall include the designated use or uses to be made of the
water, taking into account the water's use and water quality criteria necessary to protect those
uses. Water quality criteria must be based on sound scientific rationale and must contain
sufficient parameters to protect designated uses. EPA's implementing regulations at 40 CFR
131.11 require States, Territories and authorized Tribes to adopt water quality criteria based on
EPA's recommended 304(a) water quality criteria or other scientifically defensible methods.
Within the context of this guidance, States, Territories and authorized Tribes would adopt EPA's
recommended water quality criteria for bacteria, or other water quality criteria for bacteria based
on scientifically defensible methods, to protect those waterbodies designated for primary contact
recreation. Waterbodies designated for primary contact recreation may vary from small, locally
known swimming holes to large well-known bathing beaches.
EPA's current 304(a) criteria are used as the basis for Agency decisions, both regulatory
and nonregulatory, until EPA revises and reissues chemical-specific 304(a) criteria. For
example, 304(a) criteria are used in the following ways: (1) as guidance to States and Tribes for
use in establishing water quality standards; (2) as the basis for EPA promulgation of water
quality standards; (3) in establishing NPDES water quality-based permit limits, where the criteria
have been adopted by a State or Tribe or promulgated by EPA; and (4) for all other purposes of
Section 304(a) criteria under the Act. It is important to emphasize again two distinct purposes
which are served by the 304(a)criteria. The first is as guidance to States, Territories, and
authorized Tribes in the development and adoption of water quality criteria which will protect
designated uses, and the second is as the basis for promulgation of a superseding Federal rale
when such action is necessary. EPA's recommended 304(a) water quality criteria for bacteria are
based on a geometric mean calculated from samples taken over a 30-day period with no samples
exceeding a specified "single sample maximum."
In addition to the uses for EPA's recommended water quality criteria listed above, some
beach monitoring and advisory programs have used EPA's recommended water quality criteria
for bacteria to issue beach advisories and make opening and closure decisions for designated
bathing areas. While EPA encourages coordination between State water quality standards
programs and beach monitoring and advisory programs, States have considerable flexibility
when implementing EPA's water quality criteria as part of beach monitoring and advisory
programs. EPA understands that the authority for administering these programs varies from State
to State and may rest with State, local, or municipal government. When the governmental body
with the responsibility and authority for a beach monitoring and advisory program differs from a
State's water quality standards program, EPA encourages coordination of these programs to
ensure the greatest efficiency and consistency in monitoring and data collection.
Currently, there are two pending pieces of legislation in Congress which would support
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DRAFT Implementation Guidance 1or_Ambient Water Quality Criteria for Bacteria--"! 986
p. 19
both EPA water quality criteria for recreational uses and beach monitoring and public
notification programs. As currently drafted, H.R. 999 and S. 522 would require States to adopt
EPA's recommended 1986 water quality criteria for bacteria for their coastal recreation waters
and require EPA to promulgate federal water quality standards for these waters if the States fail
to do so. The bills would also establish a national beach program involving monitoring and
public notification.
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria^ 986
p. 20
4.0 Implementation of EPA's Ambient Water Quality Criteria for Bacteria - 1986
4.1 What is EPA's recommended approach for States making the transition
from fecal coliforms to ZT. coli and/or enterococci?
EPA recognizes that States that have yet to adopt EPA's recommended 1986 water
quality criteria for bacteria may be concerned about how to ensure consistency and continuity
within their regulatory programs. In addition, some States may lack an adequate database
sufficient to support certain regulatory actions. One approach States may use to address this
situation is to include both fecal coliforms and E. co/i/enteroocci in their water quality standards
for a limited period of time in order to establish an adequate database for E. coli and/or
enterococci. For States choosing this approach, EPA expects that during this limited period of
time, States will be actively collecting data on E. coli and/or enterococci and working to
incorporate E. coli and/or enterococci water quality criteria into their water quality programs,
e.g., National Pollutant Discharge Elimination System (NPDES), 305(b), and 303(d) programs.
EPA notes that a State's lack of data for £. coli and/or enterococci is not sufficient cause
for delaying adoption of the 1986 water quality criteria for bacteria into water quality standards
or, once adopted, for not serving as the basis for 303(d) listing decisions. Further, current
Agency guidance and policy explicitly reject the notion that States can avoid listing waters in
anticipation of a change to a State's water quality standards.16-17 For waterbodies previously listed
under section 303(d) for not attaining water quality standards for fecal coliforms, EPA
recommends that the waterbody continue to be included in the State's 303(d) list for pathogens
until sufficient data have been collected on E. co/z'/enterococci to either develop a Total Daily
Maximum Load (TMDL) or to support a de-listing decision. However, a State should not delay
developing a TMDL where there is an immediate threat to public health or where a waterbody
has been listed under 303(d) on the basis of fecal coliform exceedances, and such waterbody is a
priority due to court order or state statute or regulations. In these situations, the State should
develop the TMDL using the fecal coliform criterion, and monitor progress toward meeting all
bacterial water quality standards. The TMDL may need to be revised if later data show a
continuing problem under the E. co///enterococci criterion. (Note: EPA proposed in August
1999 to change its TMDL regulation to require that listed waters stay on the 303(d) list until such
time that the water quality achieves water quality standards. See 64 Fed. Reg. 46012, 46049
(Aug. 23,1999). If this proposed change is promulgated, then the above recommendation is
modified accordingly.)
4.2 How should EPA's recommended water quality criteria be implemented in
State, Territory, and Tribal water quality programs?
EPA's recommended water quality criteria for bacteria have several roles in State water
quality programs. To enable the various water quality programs to fully implement the water
quality criteria for bacteria, States should adopt both a single sample maximum (based on the
expected frequency of use) and a geometric mean into their water quality standards. As
recommended in the water quality criteria, the single sample maximum for designated bathing
areas should be used for those areas. In applying the other recommended values for single
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacter/a-1986
P. 21
sample maxima for less frequently used recreational waters, States should use their best
judgment, considering the activities taking place or that may take place on the waterbodies
within the State. EPA encourages States to utilize the single sample maxima recommended in
the 1986 water quality criteria for bacteria, unless, as outlined in the water quality criteria, data
are collected to tailor the single sample maximum values to site-specific conditions.
The following discussion regarding the implementation of EPA's 1986 water quality
criteria for bacteria are based on EPA's recommendations for adopting geometric mean values
and single sample maxima. In addition to using the water quality criteria for bacteria within
water quality regulatory programs, States are encouraged to incorporate the water quality criteria
within their beach monitoring and advisory programs. Separate guidance will be prepared by
EPA's Beaches Environmental Assessment, Closure, and Health (BEACH) program in
consultation with States, Territories, Tribes, other federal agencies, and the general public
recommending where and how to monitor to decide if beach advisories or closures are necessary.
(See section 3.0 and section 6.3 for further information.)
How should the primary contact recreation use be assessed and attainment determined?
The Guidelines for Preparation of the Comprehensive State Water Quality Assessments
(305(b) Reports) and Electronic Updates1* requires 1) the geometric mean of the samples taken
to not exceed the criterion and 2) the single sample maximum to be met for a waterbody to be
fully supporting its primary contact recreation use. The recommendations for preparation of
305(b) reports contained in the above document represent EPA's most recent guidance on
assessing and determining attainment of designated uses.
In some situations, there has been a misconception regarding the first required element
for assessing the status of the primary contact recreation use. Some States have mistakenly
interpreted the water quality criteria as requiring a minimum number of samples in order to
determine the attainment of the numeric water quality criteria. The confusion may have arisen
because the water quality criteria recommend a geometric mean based on five samples taken over
a 30-day period. The minimum number of samples used in the 1986 water quality criteria for
bacteria is for accuracy purposes only; clearly, more frequent sampling yields more accurate
results when determining the geometric mean. It is the geometric mean of the samples collected
in conjunction with a single sample maximum that determines attainment of the numeric water
quality criteria [e.g., CWA §303(d) listing for fresh and marine waters], regardless of the number
collected. This interpretation encourages the collection and use of data and is what has always
been intended. EPA notes that this interpretation was used by the Agency when promulgating
water quality standards for the Colville Confederated Tribes (40 CFR 131.35).
EPA recommends that recreation waters should be continuously monitored throughout
the swimming season, particularly waters that are designated bathing areas, to ensure human
health is adequately protected. However, there may be some waterbodies that merit less frequent
monitoring. For waterbodies that are designated for primary contact recreation but are
infrequently used by the public for recreation, it may not be possible to monitor frequently due to
resources or other constraints. For situations such as these, EPA intends to explore more fully
how data collected under these circumstances may be applied in making designated use support
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria--1986
p. 22
decisions and attainment determinations as it develops the forthcoming Assessment Methodology--
Guidance. For designated bathing areas, additional monitoring guidance will be contained in the
National Guidance for Recreational Beach Managers. (See section 6.0 for additional
information about these future documents.) Regardless of the frequency of use, when monitoring
indicates higher than normal levels of indicator bacteria, sanitary surveys should be conducted to
determine and control the source. (See section 2.1 for recommendations on conducting sanitary
surveys.)
How should permit limits be established for EPA's recommended water quality criteria for
bacteria?
Attainment of water quality criteria for bacteria is a critical component of ensuring
attainment of primary contact recreation uses. Once adopted as water quality standards by
States, Territories, authorized Tribes, or EPA, these water quality criteria form the basis for water
quality program actions, both regulatory and non-regulatory. For example, water quality criteria
are used in establishing National Pollutant Discharge Elimination System (NPDES) water
quality-based effluent limitations (WQBELs), are used as the basis for listing impaired waters
under section 303(d), and may be used for beach monitoring and advisory programs. Under the
Clean Water Act and the implementing federal regulations, States have flexibility in how they
translate water quality standards into NPDES permit limits to ensure attainment of designated
uses.
Many States have raised concerns regarding how EPA's 1986 water quality criteria for
bacteria should be implemented through NPDES permits. The Agency is aware that States have
taken different approaches in deriving NPDES permit limits for pathogens to ensure the ambient
water quality criteria are met. For example, many States apply the ambient water quality criteria
for bacteria directly to the discharge with no allowance for in-stream mixing (this is often
referred to as "criteria end-of-pipe"). Alternatively, some States provide mixing zones for
bacteria, and derive permit limits that account for in-stream dilution. EPA has also stated that for
certain types of regulated discharges [e.g., municipal separate storm sewer systems (MS4s),
concentrated animal feeding operations (CAFOs)], the most appropriate permit requirements
may be non-numeric controls such as best management practices (BMPs). The underlying
principle, however, is that whichever approach the permitting authority uses, the permitting
authority must determine that permit limits and requirements derive from and comply with
applicable water quality standards.
With respect to determining whether WQBELs for pathogens are needed for a specific
discharge, the Agency expects permitting authorities to use the same approach that applies to
other pollutants. Thus, the permitting authority must include a WQBEL in the NPDES permit
for any discharger if it determines that a pollutant (including all pathogenic pollutants) is or may
be discharged at a level which will cause, have reasonable potential to cause, or contribute to an
exceedance of any State water quality standard. See 40 CFR 122.44(d)(l)(i). When a State
adopts new water quality criteria for E. coli and/or enterococci, it must immediately begin
implementing these criteria through its NPDES permitting program. Additionally, if the State
chooses to retain an existing water quality criterion for fecal coliforms, the State must continue to
U.S. EPA Headquarters Library
Mail code 3201
1200 Pennsylvania Avenue NW
Washington DC 20460
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DRAFT Implementation Gujdance for Ambient Water Quality Criteria for Sactef/a-1986
p. 23
implement this criterion in the form of a WQBEL as well.
Following adoption of water quality criteria for E. coli and/or enterococci, the Agency
does not believe that permitting authorities will typically need to reopen existing permits prior to
their expiration dates to incorporate WQBELs based on the newly adopted water quality criteria.
Instead the Agency expects that existing WQBELs for fecal coliforms will continue to be
enforced through the existing permit's term, and that permitting authorities will incorporate
WQBELs based on newly adopted water quality criteria (as needed) at the time of permit
issuance.
States that eliminate their water quality criterion for fecal coliforms when they adopt
water quality criteria for E. coli and/or enterococci should also be aware of NPDES
"antibacksliding" provisions. The CWA and implementing NPDES federal regulations contain
specific restrictions on when an existing WQBEL may be removed or replaced with a less
stringent effluent limitation in a reissued NPDES permit. See CWA section 402(o). It is the
Agency's position that when a State replaces a fecal coliform criterion with water quality criteria
for E. coli and/or enterococci, that the replacement will not generally result in less stringent
effluent limits in the permit. In other words, if all other factors are unchanged, the WQBEL(s)
based on the newly adopted water quality criteria (for E. coli and/or enterococci) will not be less
stringent than the previous WQBEL (for fecal coliform) and the backsliding prohibitions in
section 402 of the CWA and its implementing regulations do not apply.
How should EPA's recommended water quality criteria be applied to non-human sources of fecal
contamination?
Today, EPA is changing its policy to recommend that States, Territories, and authorized
Tribes apply the 1986 water quality criteria for bacteria or other water quality criteria for bacteria
based on scientifically defensible methods to all waterbodies designated with primary contact
recreation in order to ensure protection of human health from gastrointestinal illness. The relative
health risk from waters contaminated by human sources versus non-human sources has been the
subject of recent debate, particularly related to the application and implementation of EPA's
recommended water quality criteria. Livestock, wildlife (especially waterfowl and deer), and
domestic pets can contribute significant numbers of indicator bacteria to waterbodies. In the 1994
Water Quality Standards Handbook19 EPA established a policy that States may apply water
quality criteria for bacteria with the rebuttable presumption that the indicators show the presence
of human fecal contamination. This policy was based on the absence of data correlating non-
human sources of fecal contamination and human illness and on the belief that pathogens
originating from non-human sources present an insignificant risk of gastrointestinal illness in
humans.
Recent evidence indicates that warm-blooded animals other than humans may be
responsible for transmitting pathogens capable of causing illness in humans. Examples include
outbreaks of enterohemorrhagic £. coli 0157:H7, Giardia, and Cryptosporidium, all of which are
frequently of animal origin. These pathogens can cause significant gastrointestinal illness,
although direct measurement of these organisms is not readily quantified by current conventional
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria-1986
p. 24
microbial methods. In addition, while such non-human sources may be less significant in the
transmission of the kinds of gastrointestinal illnesses identified in EPA's original
epidemiological studies, the bacterial indicators contributed by non-human sources may also
indicate risks of other human illnesses.
EPA recognizes that a study was conducted by Calderon et a/20 to determine if the human
health risk from animal sources could be quantified. The study was conducted on a small 3-acre
pond in a semi-rural community in central Connecticut and examined the relationship between
water quality degraded by dispersed, unidentified sources of animal fecal contamination and
swimmer illness. It found that although large numbers of indicator organisms were contributed
to the waterbody by animals, the resulting health risk was insignificant to swimmers. This study
concluded that EPA's currently recommended bacterial indicators are ineffective for predicting
potential health effects associated with water contaminated by non-point, i.e., animal sources, of
fecal pollution.
EPA believes that this one study does not provide an adequate basis to conclude that non-
human sources of fecal contamination have no potential to cause gastrointestinal illness in
humans. For this reason, EPA believes it is not appropriate for the application of bacteria water
quality criteria to distinguish between human and non-human sources. Until the time that a
relationship between non-human sources of fecal contamination and human illness rates is
established, EPA will continue to recommend the application of its water quality criteria for
bacteria or other water quality criteria for bacteria based on scientifically defensible methods to
all waterbodies designated with primary contact recreation in order to ensure protection of human
health from gastrointestinal illness. Therefore, EPA is changing its policy regarding non-human
sources of fecal contamination from what was previously contained in the Water Quality
Standards Handbook on this issue.
While EPA believes a change in this policy is necessary to ensure protection of human
health, EPA acknowledges such a change may present States with difficulties where the ambient
water quality criterion is routinely exceeded due to non-anthropogenic sources of pollution, such
as wildlife. Anthropogenic sources include sources related to man's activities, such as animal
production agriculture, which may be controlled by effluent limitations or best management
practices. Examples of non-anthropogenic and potentially uncontrollable sources are wildlife
refuges or lakes frequented by waterfowl. For waterbodies such as these, where the source of
fecal contamination is shown to be solely from uncontrollable natural sources and a State
demonstrates the water quality criteria for bacteria or the primary contact recreation designated
use is not attainable, EPA offers two options.
Under the first option, a State, Territory, or authorized Tribe may adopt a site-specific
water quality criterion for such waterbodies. Such a criterion must ensure protection of the
designated uses of the waterbody and be scientifically defensible. It is EPA's policy that when
reviewing such a change, EPA will evaluate if a State has demonstrated that the source of fecal
contamination is from a natural source and uncontrollable by either effluent limitations or best
management practices. This can be done through a sanitary survey or other monitoring that
adequately demonstrates the sources affecting the waterbody are from uncontrollable natural
sources. (See section 2.1 for recommendations on conducting sanitary surveys.) The State
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should also collect data to show what ambient concentrations of indicator bacteria are occurring,
and provide its rationale supporting a site-specific criterion protective of the designated uses of
that waterbody. EPA notes that in the development of a site-specific criterion, the data should be
analyzed using the EPA formulas in Ambient Water Quality Criteria for Bacteria-19%6 to
calculate the log standard deviations and single sample limits of appropriate stringency.
The second option available to States is to change the designated use of the waterbody.
This would require a use attainability analysis (UAA), consistent with 40 CFR 131.10,
demonstrating that the current designated use is not an existing use and justifying that the use is
not attainable. Under 40 CFR 131.10(j), States are required to conduct a use attainability
analysis whenever the State designates uses that do not include the uses specified in section
101(a)(2) of the CWA, when the State wishes to remove a designated use that is specified in
section 101(a)(2) of the Act, or adopt subcategories of uses that require less stringent water
quality criteria. Existing uses are defined in 40 CFR 131.3 as any use which has occurred since
November 28, 1975. In addition, designated uses are considered by EPA to be attainable, at a
minimum, if the use can be achieved (1) through effluent limitations under section CWA
§301(b)(l)(A) and (B) and §306, and (2) through cost effective and reasonable best management
practices. The federal regulation at 40 CFR 131.10 establishes the basis for finding that attaining
the designated use is not feasible, as long as the designated use is not an existing use. EPA also
emphasizes that when adopting uses and appropriate criteria, States, Territories, and authorized
Tribes must ensure that such standards provide for the attainment and maintenance of
downstream water quality standards. See 40 CFR 131.10(b).
In some instances, demonstrating that a source is an uncontrollable natural source under
the first option may be difficult. For example, waterfowl may be the only source of
contamination for a waterbody running through a golf course. As stated above, a State must
demonstrate that the contamination is solely from a natural source and is uncontrollable. With
geese as the source of fecal pollution, it qualifies as a natural source. However, in this case it is
human activity, i.e., the golf course, that has attracted the waterfowl and thus would be
considered an anthropogenic source. Such anthropogenic sources would be subject to best
management practices prior to determining the water quality criteria were not attainable. If, after
implementation of best management practices, the water quality criteria are determined to be
unattainable, it may be desirable to set a site-specific criterion. Implementation of best
management practices will establish how much of the fecal pollution is controllable. Upon the
implementation of best management practices, a State may then choose to develop site-specific
criteria based on the best attainable water quality.
The second option to remove the primary contact recreation use may be particularly
applicable in cases such as wildlife refuges, where the presence of the identified source of
contamination, wildlife, is desirable. Due to physical barriers and restrictions, primary contact
recreation may not be an existing use. Controlling the source of pollution would not be
appropriate by effluent limitations or best management practices, and thus the use can be
demonstrated to be not attainable. If the primary contact recreation is not an existing use and is
not attainable, the State may justify removing the primary contact recreation use.
With both options, an extensive sanitary survey would be necessary to identify all sources
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of fecal contamination and eliminate any possible source of human or controllable non-human
sources. Also, for the first option establishing site-specific criteria, the State, Territory or
authorized Tribe would need to submit information detailing the existing ambient water quality.
For the second option, documentation must be submitted to EPA demonstrating that the primary
contact recreation use is not an existing use as defined in 40 CFR 131.3. For both of these
options, EPA emphasizes the importance of public participation.
4.3 How should EPA's recommended water quality criteria be applied for
recreational waters in tropical climates?
Recent research suggests that EPA's recommended indicator bacteria, E. coli and
enterococci, may not be appropriate indicators for assessing the risk of gastrointestinal illness in
tropical recreational waters. E. coli and enterococci have been found in soils and waterbodies
where site surveys have indicated that it is unlikely that the source of these bacteria has been
human fecal contamination.2'-22-23 Some researchers have hypothesized that these bacteria
originated from other animals residing in the area and have developed mechanisms to maintain
viable cell populations for significant periods of time in the uniform tropical conditions.21
Because of this, the Hawaii Department of Health proposed Clostridium perfringens as an
alternate indicator of human fecal contamination.24
Does EPA recommend a different indicator for tropical climates?
At this time there are insufficient data and information to allow EPA to recommend a
different microbial indicator specifically for tropical waters. EPA believes that other microbial
indicators may be appropriate for tropical waters, given the potential for E. coli and enterococci
to persist in this climate. However, no studies have been published to date demonstrating the
scientific defensibility of using an alternate indicator. EPA developed its recommended 1986
water quality criteria for bacteria based on correlations of indicator organism concentrations with
gastrointestinal illness. Because bacteriological indicator water quality criteria are intended to
protect primary contact recreation uses, a State, Territory or authorized Tribe intending to
develop water quality criteria using alternate indicators should apply a risk-based methodology in
the water quality criteria development process. See 40 C.F.R. § 131.11 (b)( 1 )(iii) (scientifically
defensible methods). In addition to demonstrating a statistically significant relationship to
gastrointestinal illness, an alternate indicator should be indicative of recent contamination and be
detectable using acceptable peer-reviewed analytical methods.
Clostridium perfringens is one such organism that has been proposed by a State as a
bacteriological indicator. Hawaii recently proposed its use; however, in correspondence with
Hawaii, EPA expressed concern about the lack of demonstrated correlation between the indicator
and the incidence of gastrointestinal illness. An acceptable peer-reviewed analytical method
does not yet exist and, in addition, because C. perfringens forms spores that can survive for
extended periods of time, EPA questioned the ability of C perfringens to indicate recent fecal
contamination.
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How should States. Territories, and authorized Tribes apply EPA's recommended 1986 water
quality criteria for bacteria in tropical waters?
EPA strongly recommends conducting sanitary surveys in addition to microbial indicator
testing, especially in areas where higher than normal microbial densities are observed during
monitoring. This approach would be particularly applicable to tropical waters. (See section 2.1
for recommendations on conducting sanitary surveys.) Although a thorough sanitary survey
process may eliminate human origin as the likely source of the indicator bacteria, care should be
taken in concluding that there are no significant risks. Domestic pets and wildlife (especially
waterfowl) can contribute significant numbers of indicator bacteria. While such non-human
sources may be less significant in the transmission of the kinds of gastrointestinal illnesses
identified in EPA's original epidemiological studies, the bacterial indicators may indicate risks of
other illnesses. Recent outbreaks of enterohemorrhagic E. coli O157:H7, Giardio. and
Cryptosporidium, which are frequently of animal origin, cause significant illness.
As a general rule, the heavier the recreation population density, the more stringent the
water quality criteria should be in order to protect public health. This is the philosophy followed
by EPA in the Ambient Water Quality Criteria for Bacteria 1986, which allows a less stringent
single sample limit at less heavily used swimming locations. Site-specific criteria may be
developed following the process outlined in section 4.2 for non-human sources. EPA notes that
in the development of a site-specific criterion, the data should be analyzed using the EPA
formulas in Ambient Water Quality Criteria for Bacteria-1986 to calculate the log standard
deviations and single sample limits of appropriate stringency.
In the case of Hawaii, which proposed the adoption of C. perfringens as a bacteriological
indicator, EPA recommended the use of enterococci (expressed both as a geometric mean and
single sample maximum) as the primary bacteriological indicator for marine and fresh waters,
with C. perfringens as a secondary tracer of human fecal contamination if desired. This
approach, in conjunction with site surveys, should be adequate to protect the primary contact
recreational uses.
The above approaches are applicable, in general, to any tropical area with high
background concentrations of indicator bacteria. EPA recommends determining the source of the
bacteria by the application of the sanitary survey technique. If, based on a sanitary study, the
State determines that contamination is unlikely to be caused by human sources and other factors
have been evaluated, the State may then develop site-specific water quality criteria for bacteria as
described in section 4.2. EPA recommends such water quality criteria for bacteria follow the
EPA model of a geometric mean and single sample maximum.
4,4 Stream Flow (reserved)
4.5 Application of water quality criteria for bacteria in high flows (reserved)
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4.6 Development and adoption of site-specific water quality criteria (reserved)
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5.0 Appropriate Approaches for Managing Risk in Non-Primary Contact Recreational
Waters
Recreation occurs in many forms throughout the U.S. and frequently centers around
waterbodies and activities occumng in and on the water. To protect the public while recreating,
States have adopted primary contact recreation uses and bacteriological criteria for the majority
of the waterbodies. A primary' contact recreation use should be adopted for any waterbody where
people engage or are likely to engage in activities that could result in ingestion of the water or
immersion. These activities include swimming, water skiing, kayaking, and others. The
designation of this use should also take into account the behavior of children. Children are more
likely to engage in activities where ingestion of water is likely, even in waterbodies where
ingestion would not be likely for adults. Children will splash and swim in shallow waters that
may otherwise be considered too shallow for full body immersion.
While most recreational waters are designated for primary contact recreation to protect
people engaged in these activities, there are some waters where a recreation use with less
stringent water quality criteria may be justified. States may justify a change to the primary
contact recreation use for a waterbody through a use attainability analysis. See 40 CFR
131.10(g). These uses can include the designation of intermittent, secondary, or seasonal
recreation uses. In some instances, recreation uses may be removed altogether. Subject to the
provisions of 40 CFR 131.10, non-primary contact recreation uses may be applicable to waters
that are, for example, irreversibly impacted by wet weather events, where meeting the primary
contact recreation use at all times would result in substantial and widespread social and economic
impact, or where the climate allows primary contact recreation to occur only on a seasonal basis.
Many States have adopted seasonal and secondary contact recreation uses for
waterbodies. States with bacteriological water quality criteria based on fecal coliforms have
generally adopted a secondary contact water quality criterion of 2000 cfu/'l 00ml. This water
quality criterion has been applied to secondary contact uses and to seasonal recreation uses
during the months of the year not associated with primary recreation. The Ambient Water
Quality Criteria for Bacteria 1986 recommending E. coli and enterococci as indicators did not
recommend water quality criteria for recreation uses other than primary contact recreation. States
have cited this as one reason why they have not adopted EPA's recommended water quality
criteria.
5.1 Where should the primary contact recreation use and EPA's recommended
water quality criteria apply?
EPA recommends States designate primary contact recreation and adopt water quality
criteria to support primary contact recreation use wherever feasible to ensure protection of human
health from gastrointestinal illness. Although conditions such as the location of a waterbody,
high or low flows, safety concerns, or other physical conditions of the waterbody may make it
unlikely that primary contact recreation would occur, EPA believes that people, particularly
children, may swim or make other use of the waterbody such that ingestion may occur. Other
populations, such as kayakers or surfers may actually seek out high flow or unsafe waters in
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which to recreate. Further, EPA's recommended water quality criteria for bacteria are intended to
provide protection against gastrointestinal illness-associated pathogens, and the infectious doses
may vary depending on the individual and characteristics of the pathogen. In many instances,
particularly for immune-compromised individuals and children, this dose may be very low. This
risk from pathogens differs markedly from the effects of other risk-based water quality criteria,
such as carcinogens, which require chronic exposure to low doses of carcinogens before effects
are evident.
5.2 When is it appropriate to designate recreation uses other than primary
contact recreation?
EPA considers waters designated with primary contact recreation and waters designated
with secondary contact recreation with bacteriological water quality criteria sufficient to support
primary contact recreation to be consistent with the CWA §101 (a) goal uses. States may
designate subcategories of these recreation uses after demonstrating that primary contact
recreation is not an existing use and the water quality necessary to support the use is not
attainable based on chemical, physical, and biological analyses, as well as economic
considerations. See 40 CFR 131.10(g). Any adoption of a subcategory of recreation uses with
less stringent water quality criteria than required for primary contact recreation or the removal of
recreation uses requires the State to submit appropriate justification for the change in designated
use to EPA for review and approval. This includes instances where States adopt designated uses
with associated water quality criteria that are less protective than EPA's recommended values or
water quality criteria based on higher illness rates. (See section 5.4 for EPA's recommended
water quality criteria for non-primary contact recreation uses.) In determining whether or not
primary contact recreation is an existing or attainable use, States should take into account the fact
that in certain circumstances, people will use whatever waterbodies are available for recreation,
regardless of the physical conditions.
After considering whether a primary contact use and the water quality necessary to
support the use is attainable, a State may wish to adopt subcategories of recreation uses. These
can include the designation of intermittent, secondary, or seasonal recreation uses. Based upon
an appropriate justification, recreation uses may be removed altogether. An intermittent
recreation use may be appropriate when the water quality criteria associated with primary
contact recreation are not attainable for all wet weather events, even with well-designed and
operated systems. Meeting the water quality criteria associated with the primary contact
recreation use may be suspended during defined periods of time, usually after a specified
hydrologic or climatic event. EPA intends this designated use to be adopted for waterbodies in a
limited number of circumstances, contingent upon a State, Territory, or authorized Tribe
demonstrating that placing additional controls on sources of fecal contamination would result in
substantial and widespread social and economic impact. Further guidance on refining water
quality standards for combined sewer overflow receiving waterbodies will be contained in the
Implementation of the Water Quality-Based Provisions in the CSO Control Policy. (See section
6.4 for more information.)
Where primary contact recreation is not an existing use, a secondary contact recreation
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use with less stringent water quality criteria may be appropriate in some circumstances. For
example, a discharger may not be able to meet the primary contact recreation use without causing
substantial and widespread social and economic impact, but can meet the secondary' contact
recreation use. This would meet one of the six reasons contained in 40 CFR 131.10(g) justifying
the removal of a designated use. The secondary contact recreation use may also be applicable to
certain waterbodies where it can be demonstrated that flowing or pooled water is not present
during the months when primary contact recreation is taking place, the waterbody is not in close
proximity to residential areas, and that primary contact recreation is not an existing use. As
discussed in section 4.2, designating a secondary contact recreation use may be appropriate
where primary contact recreation is not an existing use and high levels of natural and
uncontrollable fecal pollution exist.
A seasonal recreation use may be appropriate in those states where ambient air and
water temperatures cool substantially during the winter months. For example, in many northern
areas, primary contact recreation is possible only a few months out of the year. Several States
have adopted, and EPA has approved, primary contact recreation uses and the associated
microbiological water quality criteria, for those months when primary contact recreation occurs
and have relied on less stringent secondary contact recreation water quality criteria to protect for
incidental exposure in the "non-swimming" season.
5.3 What information should be contained in a use attainability analysis to adopt
subcategories of a primary contact recreation use or to remove a primary
contact recreation use?
States should consult EPA guidance3-19 for general guidelines on conducting use
attainability analyses (UAAs) for recreation uses. The likely components of a UAA for
recreation uses may include:
physical analyses considering the actual use, public access to the waterbody,
facilities, proximity to residential areas, safety considerations, and substrate,
depth, width, etc. of a waterbody;
chemical analyses of existing water quality;
potential for water quality improvements including an assessment of nutrients and
bacteriological contaminants; and
economic/affordability analyses.
(See also Section 4.2 for changes to recreation uses for waterbodies impacted by non-
human sources)
On the subject of physical analyses, EPA has previously stated that, "Physical factors,
which are important in determining attainability of aquatic life uses, may not be used as the basis
for not designating a recreational use consistent with the CWA section 101(a)(2) goal".25 This
policy was further refined in the Advance Notice of Proposed Rulemaking on the Water Quality
Standards Regulation (63 FR 36741), which stated:
EPA's current thinking is that physical factors, alone would not be sufficient
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justification for removing or failing to designate a primary contact recreation use.
EPA's suggested approach to the recreational use question has been for States and
Tribes to look at a suite of factors such as, the actual use, existing water quality,
water quality potential, access, recreational facilities, location, safety
considerations, and physical conditions of the waterbody in making any use
attainability decision. The guidance suggests that any one of these factors, alone,
may not be sufficient to conclude that designation of the use is not warranted.2*
EPA continues to believe that downgrading or removing recreational uses due only to physical
conditions is inappropriate when it is otherwise feasible to meet water quality standards.
However, when considered with other data collected for a UAA, there are a few instances where
physical considerations may play an important role. This may include a waterbody where access
is prevented by fencing or in an urban waterbody that also serves as a shipping port or has close
proximity to shipping lanes. It may also include waterbodies where primary contact recreation is
not an existing use, it can be demonstrated that flowing or pooled water is not present during the
months when recreation is taking place, and that the waterbody is not in close proximity to
residential areas. In instances such as these, the physical attributes help to ensure primary
recreation does not and will not occur in these waterbodies.
EPA understands that substantial and widespread social and economic impacts are often
determining factors in assessing whether or not the primary contact recreation use and water
quality to support the use can be met. EPA has published guidance to assist States in considering
economic impacts in adopting water quality standards.26 The cost of placing additional control
measures on sources of fecal contamination are often-cited causes of being unable to meet the
primary contact recreation use and the associated water quality criteria in all waters at all times.
The federal regulation at 40 CFR 131.10(g) lists these factors that may be taken into account
when demonstrating a designated use cannot be met through a UAA, including substantial and
widespread social and economic impact, natural conditions, and physical attributes. EPA
reminds the reader that water quality criteria are derived solely on the basis of data and scientific
judgments between pollution concentrations, environment, and human health effects. While the
setting of designated uses may take into account social and economic considerations, water
quality criteria do not reflect consideration of economic impacts or the technological feasibility
of meeting the ambient criterion concentration in the waterbodies.
5.4 What water quality criteria should be applied to waters where primary-
contact recreatioD is not occurring?
Intermittent recreation uses may be appropriate for wet weather impacted waters. Such
an intermittent use may only be adopted after a State demonstrates that the primary contact
recreation use is not attainable through effluent limitations under section CWA §301(b)(l)(A)
and (B) and §306, or through cost effective and reasonable best management practices.
Determining the length of time the recreation use should be suspended and what water quality
criteria will apply during these events should be determined on a case-by-case basis taking into
account the proximity of outfalls to sensitive areas, the amount of rainfall, time of year, etc.
U.S. EPA Headquarters Library
Mail code 3201
1200 Pennsylvania Avenue NW
Washington DC 20460
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DRAFT Implementation Guidance for Ambient Water Quality Criteria for Bacteria-1986
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For waterbodies where e. State demonstrates through a use attainability analysis that
primary contact recreation will not occur, adoption of a recreation use and water quality criteria
to protect secondary contact activities may be appropriate. EPA defines secondary contact
activities as those activities where a very low percentage of participants would have very little
direct contact with the water and where ingestion of water is unlikely, such as wading, canoeing,
motor boating, fishing, etc. EPA's policy is that any secondary contact criterion adopted by a
State should be developed commensurate with the anticipated use and not exceed a geometric
mean five times EPA's recommended water quality criteria for primary contact recreation. Thus,
applying a less stringent criterion to a waterbody where a State has demonstrated that only
"secondary contact" activities are occurring should result in no greater risk of gastrointestinal
illness than waterbodies designated with primary contact recreation.
A seasonal recreation use will generally apply the water quality criteria associated with
the primary contact recreation use during the recreation season and apply less stringent water
quality criteria during the months when the ambient air and water temperatures are too cold.
During the times of year when people are not recreating in the water, a State may adopt less
stringent water quality criteria based on EPA's recommendation for secondary contact waters to
protect for incidental ingestion.
5.5 Will EPA publish risk-based water quality criteria to protect for "secondary
contact" uses?
EPA's Ambient Water Quality Criteria for Bacteria- 1986 are designed to protect the
public from gastrointestinal illnesses associated with accidental ingestion of water. EPA has not
developed any water quality criteria for secondary contact recreation to protect for other human
health-based risks. Such additional water quality criteria could conceivably be based on the
effects of dermal contact and inhalation of the water, such as rashes or other minor skin
irritations or infections. As part of EPA's Beach Action Plan, EPA intends to investigate the
development of water quality criteria for transmission of organisms that cause skin, eye, ear,
nose, respiratory illness, or throat infections. Some elements of such future water quality criteria
may potentially be applicable to secondary contact uses.
While in the future, EPA may publish additional health-based water quality criteria to
protect for health risks other than gastrointestinal illness, EPA's policy until that time is that
States should designate primary contact uses to protect against secondary exposure, unless a
State conducts a use attainability analysis to remove a primary contact recreation use or adopt a
primary contact recreation use with a less stringent criterion. In the case where a less stringent
criterion is being applied, such water quality criteria should not exceed five times EPA's
recommended water quality criteria for bacteria.
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6.0 Identification of Current and Future Activities
6.1 When will EPA propose and promulgate 24-hour methods?
The Beach Action Plan committed EPA to propose and promulgate the latest 24-hour
methods for E. coli and enterococci into 40 CFR 136. One of the reasons cited by States for not
making the transition to the 1986 water quality criteria for bacteria was that EPA's newly
validated analytical methods for E. coli and enterococci had not been promulgated as methods
under 40 CFR 136. EPA's National Pollutant Discharge Elimination System (NPDES) permit
regulations allow the use of methods not included in 40 CFR 136; however without promulgation
of the methods into 40 CFR 136, it is difficult for the permitting authority to require the use of
the methods in permits. This proposal would make available a suite of multiple-tube and
membrane filter test procedures for enumerating (determining organism density) E. coli and
enteroccoci bacteria in water as part of State, Territory, Tribal, and local water quality
monitoring programs. Thus, EPA intends to propose the methods for adoption into 40 CFR 136
by May 2000.
EPA has initiated this process, and it is undetermined at this time what methods other
than those developed by EPA's Office of Research and Development will be included in the
proposed rulemaking. However, EPA intends to propose all methods for which a suitable
supporting database is available to demonstrate acceptable performance.
6.2 When will EPA develop a laboratory techniques video?
In 1986, EPA revised its bacteriological ambient water quality criteria recommendations
to include new indicator bacteria, E. coli and enterococci, which provide a better correlation with
swimming-associated gastrointestinal disease than the previous water quality criteria using fecal
coliform bacteria. EPA's 1986 water quality criteria for bacteria recommended the use of two
new media, modified mTEC agar for E. coli and mE agar for enterococci. A video of the test
methods was made and demonstrations were given to interested parties in various Regions.
A new video, "Improved Enumeration Media for E. coli and Enterococci," demonstrates
the four methods currently recommended by EPA, including the mE and the mEI agar methods
for enterococci and the modified mTEC and mTEC agar methods for E. coli. The purpose of the
video is to introduce and demonstrate the improved methods and help answer any questions
regarding these methods. This video will supercede the earlier video demonstrating only the
earlier laboratory methods: mEI agar method for enterococci and mTEC method for E. coli.
Accompanying the video is a laboratory manual, explaining all methods in a step-by-step
format. The laboratory manual also contains color photographs of the target colonies on all
media to aid in identification. The new video and methods manual are now available to State and
private laboratories and can be obtained by e-mailing Latisha Parker at parker.latisha@epa.gov.
If funds are available, EPA will also provide hands-on laboratory training for State and local
laboratory personnel.
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6.3 What will be addressed in the upcoming National Guidance for Recreational
Beach Managers and when will it be published?
EPA's Office of Water is currently constructing the National Guidance for Recreational
Beach Managers to assist beach managers with monitoring and public notification of recreational
waters. This document will address recreational water quality monitoring, risk assessment, risk
management, and risk communication and incorporate results of the EPA Office of Research and
Devleopment's research, input from EPA's Office of Water programs, and technical input from
State and local stakeholders. EPA expects to complete the first draft by the end of FY2000.
6.4 What will be addressed in the upcoming Implementation of the Water Quality-
based Provisions in the CSO Control Policy and when will it be published?
EPA intends to publish a draft of the Implementation of the Water Quality-Based
Provisions of the CSO Control Policy for public review and comment in April 2000. The draft
guidance will lay a strong foundation for integrating the development and implementation of
long-term combined sewer overflow (CSO) control plans with water quality standards reviews
for CSO-receiving waters.
6.5 What will be addressed in the upcoming Assessment Methodology Guidance
and when will it be published?
EPA intends to publish the Assessment Methodology Guidance in the fall of 2000 in
conjunction with the final Water Quality Planning and Management Regulation. On August 23,
1999, EPA proposed revisions to the Water Quality Planning and Management Regulation,
including revisions to the process by which waterbodies are listed as impaired under §303(d) of
the CWA. The objective of the assessment methodology guidance is to help improve the
scientific basis of decisions characterizing waters as attaining water quality standards and
identifying threatened and impaired waters. It will provide guidance on data quality, data
interpretation, acceptable error, while acknowledging variation in topography, geology,
hydrology, and land use that may influence the way a State, Territory, or authorized Tribe
interprets or applies the guidance.
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References
1. Cabelli, V.J., Health Effects Criteria for Marine Recreational Waters. 1983. U.S.
Environmental Protection Agency. EPA-600/1-80-031.
2. Dufour, A.P. 1984. Health Effects Criteria for Fresh Recreational Waters. U.S.
Environmental Protection Agency. EPA-600/1 -84-004.
3. United States Environmental Protection Agency. 1986. Ambient Water Quality Criteria for
Bacteria- 1986. U.S. Environmental Protection Agency. EPA-440/5-84-002.
4. Pruss, A. 1998. Review of Epidemiological Studies on Health Effects from Exposure to
Recreational Water. International J. Epidemiology 27:1-9.
5. Fattal, B. 1987. The Association Between Seawater Pollution as Measured by Bacterial
Indicators and Morbidity Among Bathers at Mediterranean Bathing Beaches of Israel.
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6. Cheung, W.H.S., Chang, K.C.K. and Hung, R.P.S. 1990. Health Effects of Beach Water
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7. Balarajan, R., Soni Raleigh, V., Yuen, P., Wheeler, D., Machin, D. and Carrwright, R. 1991.
Health Risks Associated with Bathing in Sea Water. Brit. Med. J. 303:1444-1445.
8. Von Schimding, Y.E.R., Kfir, R., Cabelli, V., Franklin, L. and Joubert, G. 1992. Morbidity
Among Bathers Exposed to Polluted Seawater - A Prospective Epidemiological Study. South
African Medical Journal 81:543-546.
9. Corbett, S.J., Rubin, J.L., Curry, O.K., and Kleinbaum, D.G. 1993. The Health Effects of
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