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Updated July 8, 2016
Restoring Chesapeake Bay’s Water Quality: Where It Stands
Since 2009, the Chesapeake Bay jurisdictions (New York,
creating so-called dead zones, which are harmful to aquatic
Pennsylvania, Delaware, Maryland, Virginia, West
life. Sediment also depletes water of oxygen. To implement
Virginia, and the District of Columbia) have made progress
the TMDL, the Bay jurisdictions created state-specific plans
in reducing pollutants that impair the quality of Bay waters.
called Watershed Implementation Plans, or WIPs. The
However, further reductions are needed in order to reach
WIPs provide detailed plans of specific pollutant reductions
water quality goals established for the Bay by 2025.
required of sectors such as agriculture and wastewater
Basinwide, nitrogen loadings to Bay waters will need to be
treatment. The WIPs track progress toward achieving two
reduced an additional 20.4% from levels measured in 2015,
goals established in the TMDL—an interim goal of having
phosphorus loadings will need to be reduced an additional
60% of cleanup practices and policies needed to attain
5.8%, and sediment loadings will need to be reduced an
water quality standards in place by 2017 and 100% of
additional 8.6% by 2025.
practices and policies in place by 2025. Each jurisdiction
also established interim, two-year cleanup goals called
Background
milestones. The two-year milestones and progress reports
Despite several decades of activity by governments, the
are intended to be critical tools for holding the states and
private sector, and the general public, efforts to improve
the federal government publicly accountable. WIPs provide
and protect the Chesapeake Bay watershed have been
states with flexibility to determine the mix of specific
insufficient to meet restoration goals. Although some
controls they deem appropriate to meet the overall
specific indicators of Bay health have improved slightly or
reduction goals. The TMDL also embodies an adaptive
remained steady recently (such as blue crab populations and
management framework that allows states to modify their
underwater bay grasses), others remain at low levels of
strategies to achieve reductions in the most efficient way.
improvement, especially water quality. Scientists conclude
that overall, the Bay and its tributaries remain in poor
The Chesapeake Bay TMDL has been controversial with a
health, with polluted water, reduced populations of fish and
number of groups over concerns about implementation
shellfish, and continued degradation of habitat and
costs and fear that it will hamper economic growth.
resources. The primary pollutants causing impairments are
Challenges to the TMDL were brought by agricultural and
excess nutrients (nitrogen and phosphorus) and sediment
home builder groups, who argued that EPA had exceeded
discharged from multiple urban, suburban, and rural
its authority and impinged on the responsibilities of states
sources around the Bay. Agriculture is the principal source
to manage water quality. Federal courts rejected the
of these pollutants. Reducing pollution is critical to
challenges and upheld the TMDL.
restoring the watershed, because clean water is the
foundation for healthy fisheries, habitats, and communities
2016 Evaluations of Progress
across the region.
In June 2016, EPA provided evaluations of the
jurisdictions’ progress towards meeting their sector-specific
In May 2009, President Obama issued an executive order
2014-2015 milestones and progress toward the 2017 and
that declared the Bay watershed a “national treasure” and
2025 goals. EPA compared 2015 measured loads with 2009
charged the federal government with developing a new
levels, the year before the TMDL began. (EPA’s
strategy for protecting and restoring the Chesapeake region.
evaluations are available at https://www.epa.gov/
A central feature of the strategy was development of a Total
chesapeake-bay-tmdl/epa-oversight-watershed-
Maximum Daily Load (TMDL) for Chesapeake Bay by the
implementation-plans-wips-and-milestones-chesapeake-
Environmental Protection Agency (EPA). A TMDL is a
bay.) For each jurisdiction, EPA evaluated these sectors:
pollution budget, containing a scientific calculation of how
agriculture, urban/suburban stormwater, wastewater and
much pollutant loadings need to be reduced to achieve
combined sewer overflows (CSOs), onsite septic systems,
state-established water quality standards. (For background,
and forestry.
see CRS Report R42752, Clean Water Act and Pollutant
Total Maximum Daily Loads (TMDLs).)
In 2015, for the Chesapeake Bay basin as a whole,
phosphorus loading was down 20%, nitrogen loading was
The Chesapeake Bay TMDL is the largest single TMDL
down 7%, and sediment loading was down 7%, compared
developed to date. It addresses all segments of the 64,000-
with 2009. However, reductions of specific pollutants in
square-mile Bay watershed, including tidal tributaries.
individual jurisdictions varied widely (see Figure 1).
Nitrogen and phosphorus are considered the main
Collectively, the Bay jurisdictions are on track to meet the
contributors to poor water quality because, in excess
watershed-wide 2017 targets for phosphorus and sediment,
amounts, they spur algae blooms, which block sunlight
but not nitrogen. While the goal is to achieve 60% of the
critical to underwater grasses that support crabs, fish, and
load reduction by 2017, nitrogen is currently projected to be
waterfowl. When the algae die, they sink to the bottom and
at only 46% of the 2017 targeted reduction. Looking toward
decompose in a process that depletes the water of oxygen,
the 2025 goal, EPA made the following assessments.
https://crsreports.congress.gov
Restoring Chesapeake Bay’s Water Quality: Where It Stands
The District of Columbia has essentially achieved the
increased slightly, and loading of all pollutants from
2025 goals for nutrient and sediment reduction, but will
forestry sources declined slightly.
need to place emphasis on the urban/suburban
stormwater sector to stay on track.
In its 2016 evaluations, EPA found that the wastewater
sector of Bay jurisdictions is on track to achieve the 2017
Delaware and Maryland are on track to meet the 2025
nitrogen load targets, but the agriculture, stormwater, and
goals for phosphorus and sediment, but both need to
onsite septic sectors are off-target for meeting nitrogen
make progress to limit nitrogen discharges, especially
reductions. For phosphorus, all sectors except
from the agriculture and stormwater sectors.
urban/suburban stormwater achieved the 2017 targets. For
sediment, the wastewater sector of the Bay jurisdictions
West Virginia has essentially achieved the 2025 goals
achieved the 2017 targets, but the agriculture and
for sediment, but needs to make progress to limit
urban/suburban stormwater sectors are off-target. Looking
nitrogen and phosphorus discharges by all sectors.
toward 2025, EPA made the following assessments.
Pennsylvania and New York need to significantly
Agricultural sources and urban/suburban stormwater
increase the level of effort to reduce loads of all three
runoff sources need to make significant progress in
pollutants in order to meet the 2025 goals.
reducing discharges of nitrogen, phosphorus, and
sediment. Urban runoff is one sector that has shown
Virginia is on track but needs to make progress to limit
increases in loadings—especially nitrogen—since 2009.
loadings of all three of the pollutants by 2025.
Wastewater treatment and CSO sources of sediment
Figure 1. Chesapeake Bay Pollution Reduction
discharges have essentially achieved the 2025 goals, but
Progress Toward 2025 Goals (By Jurisdiction)
need to make progress to limit nitrogen and phosphorus.
(Million pounds/year)
Onsite septic systems, a source of nitrogen discharges,
need to make progress to achieve the 2025 goals.
Forestry sources are on track to achieve the 2025 goals
for all pollutants.
EPA works with and maintains oversight of the Chesapeake
Bay jurisdictions to help them achieve pollution reduction
goals on schedule. If a jurisdiction’s progress is insufficient,
EPA may take federal actions to get them back on track,
such as using Clean Water Act authority to expand permit
coverage to unregulated sources, increase federal
enforcement and compliance, or redirect EPA grants.
Challenges
EPA and other stakeholders acknowledge that, despite
progress on the Bay’s cleanup efforts, challenges remain.
Sectors and jurisdictions that are close to or have
essentially attained the 2017 and 2025 goals will need to
stay on track to maintain their progress, even as
economic development and population growth occur.
States will need to improve and accelerate
implementation of priority best management practices
(BMPs) in the agriculture and urban/suburban
stormwater sectors, if they are to meet their future
Source: Calculations by CRS, from Chesapeake Bay Program,
commitments.
http://chesapeakeprogress.com/Data_2015_Reducing_Pollution_04-
15-2016.xlxs.
Perhaps the key challenge is providing adequate funding
for wastewater infrastructure upgrades and
EPA also evaluated progress by sectors in the watershed. In
improvements in several jurisdictions and BMP
2015, compared with 2009, agricultural sources reduced
implementation throughout the Chesapeake Bay region.
discharges of nutrients and sediment. Urban/suburban
stormwater runoff loadings of nitrogen and sediment
increased slightly, compared with 2009, while phosphorus
Claudia Copeland, Specialist in Resources and
loading declined. Discharges of all three pollutants from
Environmental Policy
wastewater treatment and combined sewer overflow sources
IF10283
declined. Onsite septic system discharges of nitrogen
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Restoring Chesapeake Bay’s Water Quality: Where It Stands
Disclaimer
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