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January 8, 2020
Status of Efforts to Restore Chesapeake Bay Water Quality
Background
tracking and assessment, and backstop federal actions if bay
For decades, Chesapeake Bay jurisdictions (Delaware,
jurisdictions do not meet their commitments. Examples of
Maryland, New York, Pennsylvania, Virginia, West
potential backstop federal actions include expanding CWA
Virginia, and the District of Columbia), multiple federal
permit coverage to unregulated sources, conditioning or
and local agencies, and others have worked to improve
redirecting EPA grants, and requiring additional pollutant
water quality in the Chesapeake Bay. Despite these
load reductions from point sources.
extensive restoration efforts, poor water quality in the bay
and its tidal tributaries persisted, prompting litigation that
WIPs and Milestones
ultimately required the U.S. Environmental Protection
Bay jurisdictions have each created WIPs, which detail
Agency (EPA) to establish a Total Maximum Daily Load
specific steps the jurisdiction plans to take to meet and
(TMDL)—or a “pollution budget” for the bay. Established
maintain its pollutant allocations under the TMDL. Bay
in 2010, the TMDL included interim and final goals for
jurisdictions have developed WIPs in three phases. Phase I
each jurisdiction to achieve by 2017 and 2025, respectively.
and II WIPs, submitted to EPA in 2010 and 2012,
respectively, described specific actions and controls to be
What Is a TMDL?
implemented by 2017 and 2025 to achieve applicable water
The Clean Water Act (CWA) requires states to identify
quality standards. Phase II WIPs built upon Phase I WIPs
waters that are “impaired” by pollution (i.e., not meeting
by including more specific local actions. Phase III WIPs
state water quality standards). For those waters, the act
include specific steps the jurisdictions intend to take
directs states to establish a TMDL, which is a calculation of
through 2025 to meet the goals of the TMDL (see “Phase
the amount of a pollutant that can enter a waterbody and
III WIPs”). Bay jurisdictions submitted final Phase III
still allow the waterbody to meet state water quality
WIPs to EPA in August 2019.
standards for that pollutant. TMDLs include a quantitative
assessment of the pollutant sources and reductions required
Each jurisdiction has also established interim, two-year
to attain water quality standards. TMDLs address both point
accountability goals called milestones. The bay jurisdictions
sources of pollution (e.g., wastewater treatment or industrial
submitted their first set of milestones to EPA in 2012.
plant discharges) and nonpoint sources (e.g., urban runoff
These milestones identify short-term goals, which can be
and agricultural runoff). The CWA directs states to submit
used to assess progress toward the longer-term goals. Bay
TMDLs to EPA for approval. If EPA disapproves, the act
jurisdictions may also use milestones to update
directs EPA to develop a TMDL for the waterbody.
programmatic or numeric commitments as part of an
adaptive management process. The most recent set of
Chesapeake Bay TMDL
milestones covered 2018-2019.
EPA established a Chesapeake Bay TMDL in 2010
pursuant to consent decrees resolving litigation over
2017 Midpoint Assessment
impairment of bay waters in Virginia and the District of
The Chesapeake Bay TMDL called for a midpoint
Columbia. The TMDL was also a key feature of a 2010
assessment in 2017 to review bay jurisdictions’ progress
strategy to restore the Chesapeake Bay, which the Federal
toward meeting the goals established in the TMDL. In
Leadership Committee for the Chesapeake Bay, chaired by
2018, EPA released the results of that assessment.
EPA, created in response to Executive Order 13508, issued
According to data submitted by bay jurisdictions to EPA,
in May 2009. The order declared the bay watershed a
the jurisdictions collectively exceeded the 2017 interim
“national treasure” and charged the federal government
goals for reducing phosphorus and sediment, but they did
with developing a new strategy for protecting and restoring
not achieve the 2017 interim goal for reducing nitrogen.
the Chesapeake region.
Reductions of specific pollutants in individual bay
jurisdictions varied widely (Figure 1).
The Chesapeake Bay TMDL is the largest single TMDL
developed to date in terms of area covered. It addresses all
EPA also assessed the bay jurisdictions’ implementation of
segments of the bay and its tidal tributaries that are
programs to achieve pollution reductions across sectors and
impaired from discharges of nitrogen, phosphorus, and
found that achievements and shortfalls varied. The
sediment. The TMDL set two broad goals: an interim goal
wastewater sector, in particular, had much success,
of having 60% of pollution control measures needed to
achieving its 2025 load reduction goals 10 years ahead of
attain water quality standards in place by 2017 and a final
schedule through treatment plant upgrades, technology
goal of having 100% of the measures in place by 2025.
advances, and limiting discharges of nutrients in CWA
EPA is using an accountability framework to implement the
discharge permits. Efforts to reduce nitrogen deposition
TMDL. This framework includes four elements: watershed
from atmospheric sources (e.g., power plants and vehicles)
implementation plans (WIPs), two-year milestones, EPA
were also on track to meet the 2025 TMDL goals. However,
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Status of Efforts to Restore Chesapeake Bay Water Quality
while states had improved their urban/suburban stormwater
needing enhanced oversight. In addition, EPA identified
regulatory programs, EPA reported that overall loads in the
two sectors in Pennsylvania—agriculture and
sector continue to increase due to population growth and
urban/suburban stormwater—as requiring backstop action
development. EPA also found that, in some cases, states
levels, meaning the agency has substantial concerns with
were not making sufficient progress in implementing their
actions to meet the TMDL goals. For these two sectors,
planned policies and programs in the agricultural sector and
EPA has taken actions intended to get the jurisdiction on
were falling short of meeting pollution reduction goals.
track to meet its goals, such as establishing an expectation
Figure 1. Chesapeake Bay Pollution Reduction
for more frequent and detailed reporting and an expectation
Progress Toward 2025 TMDL Goals (by Jurisdiction)
that Chesapeake Bay funds provided to Pennsylvania would
be applied to specific priority watersheds.
Phase III WIPs
In August 2019, EPA received final Phase III WIPs from
bay jurisdictions specifying actions they plan to implement
between 2019 and 2025 to achieve the TMDL goals. Phase
III WIPs consider the 2017 midpoint assessment results and
new science and data, such as improved modeling tools,
higher-resolution land cover data, additional monitoring
data, and greater variety of approved best management
practices. Phase III WIPs also consider changing conditions
such as population growth, land use changes, and climate
change. In July 2018, a committee comprised of members
from EPA and other bay partners revised nitrogen and
phosphorus targets reflecting refinements to the most recent
version of the program’s watershed model (Figure 1,
“Phase III WIP Target”). Some of these revised targets
require additional pollution reductions beyond the original
2025 goals, whereas other targets require lesser reductions.
The new targets reflect that pollution controls in some
watershed areas may be more effective than similar controls
in other areas.
Challenges
EPA and other stakeholders acknowledge that, despite
progress in reducing pollutants to the bay, challenges
remain. Identified challenges include securing funding for
wastewater and stormwater infrastructure upgrades and for
best management practices and continuing to reduce
nutrients in the face of economic development, population
growth, increased storm events, and other factors. Some
stakeholders also assert that the largely voluntary approach
to restoring waters impaired by nonpoint source pollution,
such as some agricultural sources, can make it challenging
to achieve targets. EPA asserts that jurisdictions can reduce
nutrients from such sources when states have effective
Source: CRS analysis of data from ChesapeakeProgress,
regulatory programs, voluntary programs that incentivize
https://www.chesapeakeprogress.com/clean-water/2017-watershed-
farmers to reduce runoff, and/or cost share and other
implementation-plans and https://www.chesapeakebay.net/documents/
financing programs that supplement U.S. Department of
Phase_III_WIP_Planning_Targets.pdf.
Agriculture programs to support conservation practices on
Note: EPA also has a 2025 target for atmospheric deposition of
farms.
nitrogen to tidal waters (15.2 mil ion pounds/year).
Congress has funded efforts to restore the Chesapeake Bay
In 2018, as part of its midpoint assessment, EPA updated
and its water quality through EPA and other agencies for
the oversight levels for four sectors in each jurisdiction:
decades. The President’s FY2020 budget request proposed
agriculture, urban/suburban stormwater, wastewater, and
to reduce the budget for the Chesapeake Bay Program and
trading/offsets. The agency identified certain sectors within
certain other programs that may be used to address
certain bay jurisdictions as needing enhanced oversight,
nonpoint source pollution. However, Congress increased
meaning EPA may take additional actions to ensure that the
FY2020 appropriations for the program to $85 million (P.L.
jurisdiction stays on track. For these sectors/jurisdictions,
116-94). Additionally, in 2018, Congress reauthorized
EPA identified specific concerns with the jurisdictions’
CWA Section 221 grants for municipalities and expanded
implementation of strategies to meet TMDL goals. EPA
project eligibility to include measures to address
ranked Delaware’s agricultural sector, Maryland’s
stormwater. P.L. 116-94 provides the first appropriations
urban/suburban stormwater sector, New York’s wastewater
for this grant program: $28 million for FY2020.
sector, and Pennsylvania’s trading/offsets sectors as
Laura Gatz, Analyst in Environmental Policy
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Status of Efforts to Restore Chesapeake Bay Water Quality
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