United States
Environmental Protection
  Office of Water
    March 2016
Six  Key  Steps  to  Developing and  Using
Predictive Tools  at Your  Beach
EPA has published the document, Six Key Steps to
Developing and Using Predictive Tools at Your Beach,
to provide a simple, straightforward approach on
how to develop a predictive tool (i.e., model) for
beach water quality. EPA developed this guidance to
promote use of predictive tools in state beach
programs and encourage beach managers to
investigate whether a predictive tool would be an
appropriate and cost-effective addition to their
beach monitoring and notification programs to
improve public health protection. Predictive tools
enhance current monitoring techniques by
anticipating when water quality conditions might
States, territories, tribes, and local jurisdictions
monitor coastal recreation waters to determine if
people swimming and playing in these waters are
safe from exposure to fecal contamination. The
culture-based test method that is currently widely
used for assessing water quality conditions at
beaches results in delays in notifying the public of
water quality problems. This "persistence model"
assumes that fecal indicator bacteria densities do
not change—they persist—between the time a
water sample  is taken and the laboratory results are
known. Predictive models can be used to
supplement such monitoring and can help anticipate
problems due to changing conditions and enable
prompt public notification.
Incur National Beach Guidance and Required
Performance Criteria for Grants, 2014 Edition, EPA
                            encourages states, territories, and tribes to use
                            predictive tools to make timely beach advisory
                            decisions and issue same-day public notifications.
                            Performance Criteria 2 requires development of a
                            tiered monitoring plan that can adapt to changing
                            conditions and adequately protect public health.
                            States, territories, and tribes are required to
                            consider the use of predictive tools in developing a
                            tiered monitoring plan under Performance Criteria 2.
                            This guidance will help them with that consideration.
                            What's involved in developing and using
                            predictive tools at beaches?
                            This guidance describes six key steps that beach
                            programs could take to develop and use predictive
                            tools at their beaches. The guidance was informed
                            by the experiences of several beach managers who
                            have developed and/or are using predictive models
                            at their beaches,  and the Texas Beach Watch
                            program pilot-tested it.
                            Step 1 involves evaluating whether you  need a
                            model, if your beach  is a good candidate for a model,
                            and if you have the data and resources to develop
                            the model. It is the "Go - No Go" step of the  process.
                            Once a beach program has determined that a
                            predictive tool is  appropriate for their beach, the
                            remaining steps support the development,
                            evaluation and implementation of the tool.
                            Step 2 involves identifying candidate independent
                            variables and collecting high quality data for those

Step 3 involves exploring the relationship between
independent variables identified in Step 2 and fecal
indicator bacteria density.
Step 4 involves the development and testing of the
Step 5 provides factors to consider when deciding
whether to integrate the model into your beach
monitoring and notification program.
Step 6 recommends developing a plan for evaluating
the model over time to ensure that it is performing

What are the benefits of using predictive
tools at beaches?
Predictive  tools are a means to provide rapid
estimates of beach water quality conditions in the
absence of water sampling results. They can be used
to supplement, not replace, monitoring and are an
improvement to the current approach (i.e.,
persistence model) used by states, territories and
Predictive  tools offer states, territories and tribes
the potential for same day notification and public
health protection for considerably less than other
rapid methods.

Where can I find more information?
For more information about the modeling guidance,
please contact Samantha Fontenelle at
To view the guidance and other information about
predictive  models visit the EPA Beaches website at:
For general information about beaches visit the EPA
Beaches website at: http://www.epa.gov/beaches.
For more detailed technical information visit the EPA
Beaches website at: http://www.epa.gov/beach-
To find state and local government or EPA Regional
beach program contacts visit the EPA Beaches
website at: http://www.epa.gov/beaches/state-and-