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INNOVATIVE RESEARCH FOR A SUSTAINABLE FUTURE

EPA is partnering with stakeholders and communities on Cape Cod to
evaluate non-traditional approaches for reducing excess nutrients entering
coastal waters

EPA is collaborating with the
Barnstable Clean Water Coalition
(BCWC) in Barnstable, Mass., as
well as numerous stakeholders
and a team of partner
organizations in the Cape Cod
region, to explore ways to reduce
the amount of nitrogen entering the
Cape's estuaries and freshwater
ponds. Excess nutrients from
human activity are an increasingly
serious threat to estuaries,
wetlands, and freshwater ponds
nationwide, as they contribute to
algae blooms, low dissolved
oxygen, degradation of seagrass,
impaired freshwater and estuarine
ecosystems, and, in extreme
cases, fish kills.

Cape Cod has several unique
characteristics that make its
estuaries susceptible to impacts
from excess nutrients in the form
of nitrate. An estimated 80 percent
of nitrogen loading on Cape Cod
stems from the use of backyard
septic systems. Traditional septic
systems are not designed to
remove nitrogen. Wastewater
treatment plants are not widely
used on Cape Cod due to the
costs and challenges associated
with widely distributed housing and
large seasonal fluctuations in
population due to summer tourism.
Nitrate moves easily from the
septic systems to the Cape's
groundwater, where it is
transported to ponds, streams and

estuaries. In addition to septic
systems, lawn fertilization,
atmospheric deposition, and storm
water also contribute to excess
nitrogen in the region.

Collaboration Activities

EPA scientists are partnering with
BCWC, U.S. Geological Survey,
The Nature Conservancy, and the
Massachusetts Alternative Septic
System Test Center, and are
engaging additional local and state
stakeholders, including the
Massachusetts Department of
Environmental Protection,
Massachusetts Division of
Ecological Restoration, the town of
Barnstable, and the Cape Cod
Commission, to examine ways to
reduce excess nutrients. The
partners are exploring both
traditional technologies (i.e.,
centralized wastewater treatment
facilities) and alternative
technologies to reduce excess
nutrients. An initial stakeholder
engagement and problem
formulation workshop revealed key
knowledge gaps and opportunities
for collaboration. Based on the
insights from this workshop, the
team will be:

• Conducting a benthic survey of
the Three Bays estuary in
Barnstable to determine the
current condition of the estuary,
which includes North Bay, West
Bay and Cotuit Bay.

•	Designing pilot-scale
interventions to evaluate the
effectiveness of nitrogen
removal, including:

o Designing a neighborhood-
scale innovative septic
system experiment to field
test new low-nitrogen septic
system designs and
demonstrate resulting
changes in groundwater
nitrogen levels;
o Collaborating on a study to
evaluate the nitrogen
reduction potential of various
cranberry bog wetland
restoration approaches.

•	Performing greenhouse
experiments to investigate the
potential re-use of nitrogen-rich
sediments dredged from nearby
ponds and the Three Bays
estuary.

•	Investigating the benefits of
improved water quality provided
by shellfish aquaculture.

Oysters and other shellfish filter
water, consume phytoplankton,
and remove nitrogen from the
environment.

•	Comparing the ecological,
economic, and social benefits
and barriers of the various
alternative technologies.

•	Evaluating how increased
stakeholder engagement can
improve research planning and
outcomes.

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U.S. Environmental Protection Agency

Office of Research and Development

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Anticipated Results

Preliminary results are anticipated in
2021, and ultimately will be used to:

•	Determine the effectiveness of
alternative technologies for
removing nitrogen from Cape
Cod's waters and understand
which solutions will work best in
the region;

•	Assist the Cape's communities
with evaluating the benefits and
tradeoffs of implementing
different nitrogen removal
technologies.

How can I help reduce excess
nutrients?

Contact your local municipality to
learn more about their wastewater
management plans and options to
reduce your personal contribution
of nutrients to the watershed.
Engage with local organizations
such as the Barnstable Clean
Water Coalition, Cape Cod
Commission, and the Association
to Preserve Cape Cod.

Some quick tips include reducing
use of lawn fertilizer and planting
rain gardens of native plants,
shrubs and trees to provide ways
for water to soak more slowly into
the ground.

Where can I learn more?

Learn more about the Cape's
Section 208 Area Wide Water
Quality Management Plan:
www.capecodcommission.org/our-
work/208

Learn more about excess
nutrients:

www.epa.gov/nutrientpollution

CONTACTS

Nutrients Pilot Lead:

Anne Rea
rea.anne@epa.gov

Science Lead:

Tim Gleason

Gleason.timothv@epa.gov

Communications Contact:

Emily Smith
Smith.emilv@epa.gov

April, 2020

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U.S. Environmental Protection Agency

Office of Research and Development

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