x>EPA
United States
Environmental Protection
Agency
Office of Water EPA - 820-F-12-061
4305T
December 2012
2012 Recreational Water Quality Criteria
Summary
EPA has released its 2012 recreational water
quality criteria (RWQC) recommendations for
protecting human health in all coastal and non-
coastal waters designated for primary contact
recreation use. EPA provides two sets of
recommended criteria. Primary contact
recreation is protected if either set of criteria
recommendations are adopted into state water
quality standards.
These recommendations are intended as
guidance to states, territories and authorized
tribes in developing water quality standards to
protect swimmers from exposure to water that
contains organisms that indicate the presence of
fecal contamination.
Background
EPA last issued ambient water quality criteria
recommendations for recreational waters in
1986. EPA issues such recommendations under
the authority of the Clean Water Act (CWA).
Amendments to the CWA by the Beaches
Environmental Assessment and Coastal Health
(BEACH) Act of 2000 direct EPA to conduct
studies associated with pathogens and human
health, and to publish new or revised criteria
recommendations for pathogens and pathogen
indicators based on those studies. These 2012
RWQC meet those requirements.
The 2012 RWQC rely on the latest research and
science, including studies that show a link
between illness and fecal contamination in
recreational waters. They are based on the use of
two bacterial indicators of fecal contamination,
E. coll and enterococci. The new criteria are
designed to protect primary contact recreation,
including swimming, bathing, surfing, water
skiing, tubing, water play by children, and
similar water contact activities where a high
degree of bodily contact with the water,
immersion and ingestion are likely.
What are the recommendations?
The 2012 RWQC offer two sets of numeric
concentration thresholds, either of which would
protect the designated use of primary contact
recreation and, therefore, would protect the
public from exposure to harmful levels of
pathogens. Illness rates upon which these
recommendations are based use the National
Epidemiological and Environmental Assessment
of Recreational Water (NEEAR) definition of
gastrointestinal illness, which is not limited to
illnesses which exhibit a fever.
The RWQC consist of three components:
magnitude, duration and frequency. The
magnitude of the bacterial indicators are
described by both a geometric mean (GM) and a
statistical threshold value (STV) for the bacteria
samples. The STV approximates the 90th
percentile of the water quality distribution and is
intended to be a value that should not be
exceeded by more than 10 percent of the
samples taken. The table summarizes the
magnitude component of the recommendations.
All three components are explained in more
detail in the sections below.
CRITERIA
ELEMENTS
Indicator
Enterococci
(marine & fresh)
£ co/i
(fresh)
Recommendation 1
Estimated Illness Rate 36/1 .000
GM
(cfu/100mL)
35
126
STV
(cfunoOmL)
130
410
Recommendation 2
Estimated Illness Rate 32/1 .000
GM
(cfu/100mL)
30
100
STV
(cfuilOO mL)
110
320
Water quality criteria recommendations are
intended as guidance in establishing new or
revised water quality standards. They are not
regulations themselves. States and authorized
tribes have the discretion to adopt, where
appropriate, other scientifically defensible water
quality criteria that differ from EPA's
recommended criteria.
RECOMMENDATION 1: MAGNITUDE
Enterococci: Culturable enterococci at a
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geometric mean (GM) of 35 colony forming
units (CPU per 100 milliliters (mL) and a
statistical threshold value (STV) of 130 cfu per
100 mL, measured using EPA Method 1600, or
any other equivalent method that measures
culturable enterococci.
E. coli: Culturable E. coll at a GM of 126 cfu
per 100 mL and an STV of 410 cfu per 100 mL
measured using EPA Method 1603, or any other
equivalent method that measures culturable E.
coli.
RECOMMENDATION 2: MAGNITUDE
Enterococci: Culturable enterococci at a GM of
30 cfu per 100 mL and an STV of 110 cfu per
100 mL, measured using EPA Method 1600, or
any other equivalent method that measures
culturable enterococci.
E. coli: Culturable E. coli at a GM of 100 cfu
per 100 mL and an STV of 320 cfu per 100 mL
measured using EPA Method 1603, or any other
equivalent method that measures culturable E.
coli.
FOR BOTH RECOMMENDATIONS
Duration and Frequency: The waterbody GM
should not be greater than the selected GM
magnitude in any 30-day interval. There should
not be greater than a ten percent excursion
frequency of the selected STV magnitude in the
same 30-day interval.
How are these criteria different from the 1986
criteria?
Similar Protection for Fresh and Marine
Waters: The EPA used an analysis of NEEAR
water quality data to refine the illness rate
estimate for the recommended marine criterion
for entercocci. The 2012 RWQC values now
protect public health similarly in both marine
and fresh waters.
A New Measurement Value: EPA is
introducing a new term, Statistical Threshold
Value (STV), to be used in conjunction with the
recommended GM value.
New Early Alert Tool: In addition to
recommending criteria values, EPA is now also
providing states with Beach Action Values
(BAVs) for use in notification programs. The
BAV is provided for states to use as a
precautionary tool to provide an early alert to
beachgoers, including families with children.
A Single Level of Beach Use: The 1986
bacteria criteria document included four single
sample maximum (SSM) values appropriate for
different levels of beach usage (use intensities).
In the 2012 RWQC, EPA removed those
recommendations and instead provided states
with optional, precautionary BAVs for use in
monitoring and notification programs.
More Tools for Assessing and Managing
Recreational Waters: EPA is providing
information on tools for evaluating and
managing recreational waters, such as predictive
modeling and sanitary surveys. The Agency is
also providing tools for developing site-specific
criteria such as epidemiological studies,
quantitative microbial risk assessment, and use
of alternative indicators or methods. The EPA
has developed and validated a molecular testing
method using quantitative polymerase chain
reaction (qPCR) as a rapid analytical technique
for the detection of enterococci in recreational
water (EPA Method 1611). For the purposes of
beach monitoring, a state may use a qPCR
method on a site-specific basis.
Where can I find more information?
EPA has put the 2012 RWQC document,
support documents, and the Federal Register
Notice, in the docket (Docket identification No.
EPA-HQ-OW-2011-0466) which can be
accessed via EPA's website at
http://water.epa.gov/scitech/swguidance/standar
ds/criteria/health/recreation/index.cfm.
You can also contact Sharon Nappier at
nappier.sharon(g),epa.gov or (202)566-0740, or
contact Tracy Bone at bone.tracy@epa.gov or
(202) 564-5257 for more information.
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