|
 |
 |
Anacostia River Watershed District of Columbia
The Case Summary
Considerations for Using Ecological Restoration:
A Degraded Urban Watershed
The Anacostia River watershed is located in the metropolitan Washington, DC
area. It is heavily urbanized with over 600,000 residents. The Anacostia River
Watershed currently includes stakeholders of every socio-economic background,
and every form of urban and suburban land use. The watershed is included in an
area that represents the eco nomic core of the region. These circumstances
provided both significant incentives and barriers to the restoration
initiative. For example, stream restoration can be an effective catalyst for
revitalization of an economically depressed community. Over the past three
centuries, the landscape of the Anacostia watershed has been greatly
transformed by successive waves of cultivation and urbanization. As a result of
urban and suburban development in the late 19th and 20th centuries, the
watershed und erwent extensive change. Sediment deposition from agricultural
fields was augmented by runoff from construction zones and impervious surfaces.
Urbanization also brought increased flooding, further forest clearing and an
influx of pollutants and toxins i nto the waters of the Anacostia. The sewage
inputs to the tidal river added organic wastes, bacteria and debris to the
deteriorating waters of the Anacostia.
To address the rapid deterioration of the river, an intergovernmental
partnership was created by the landmark 1987 Anacostia Watershed Restoration
Agreement, signed by the District of Columbia, Montgomery County, Prince
George's County, and the State of M aryland. The Agreement formalized a
cooperative partnership to restore the Anacostia River and its tributaries. To
guide the restoration process, the Agreement called for the formation of an
Anacostia Watershed Restoration Committee to develop a restora tion plan.
Membership on the committee is broadly based and an aggressive outreach program
has extended participation in the development and implementation of the
restoration plan to over 60 public and private organizations. Public and
membership input has been substantial throughout, including the development of
the restoration goals for the Anacostia River listed in the Restoration Tools
section below. The Metropolitan Washington Council of Governments is
responsible for providing administrative and technical support to facilitate
the restoration activities of the Anacostia Watershed Restoration Committee.
The Interstate Commission on the Potomac River is charged with coordinating and
implementing public education and participation in the restoratio n effort, and
developing a living resource program for the watershed.
Stressors of Concern
The Anacostia estuary has some of the poorest water quality recorded in the
Chesapeake Bay system. It has a number of serious problems which have
contributed to its degraded ecology and poor water quality:
- it is rapidly filling with sediment and debris from upstream;
- dissolved oxygen levels frequently violate water-quality standards;
- sediments are enriched with toxicants, hydrocarbons, trace metals and
nutrients;
- many miles of stream habitats have been severely degraded by urbanization,
which has profoundly altered the flow, shape, water quality, and ecology of
these streams;
- anadromous fish migration has been blocked by numerous man-made fish
barriers;
- over 98 percent of the tidal wetlands and nearly 75 percent of the
freshwater wetlands within the watershed have been destroyed;
- nearly 50 percent of the forest cover in the basin has been lost to
urbanization, including much of the riparian vegetation; and
- the approximately 600,000 residents are generally unaware that they live in
the Anacostia watershed, and do not perceive the connection to the river and
its unique natural features.
Project Goals and Restoration Techniques
The Anacostia Watershed Restoration Program is a six-point action plan
intended to preserve and restore the chemical, physical and biological
integrity of the river. The six goals, and the means of attaining them, are
described below. Figure 6-1 presents a matrix that includes goals and
general project objectives for the Anacostia River restoration program, and the
agencies and organizations that are contributing to each objective.
Goal 1: Dramatically reduce pollutant loads in the tidal estuary to
measurably improve water quality conditions by the turn of the century.
The most significant sources of pollutant loadings are combined sewer
overflows (CSOs) and urban stormwater discharges. Therefore, to meet the goal
of dramatically reducing pollutant loadings, a sharp reduction in the number of
CSO events and stormwater pollutant loadings was necessary. This was
accomplished by the installation of innovative swirl concentrators to treat
CSOs, rehabilitation of aging sanitary sewer networks, construction of
facilities to treat stormwater runoff from older developed areas , and
requirements that new developments conform to stringent sediment and stormwater
controls. Trash and floatable debris were removed from the estuary and its
tributaries, and a widespread storm drain "Don't Dump" posting program was
implemented to pre vent the introduction of additional trash and debris.
Goal 2: Restore and protect the ecological integrity of degraded urban
Anacostia streams to enhance aquatic diversity and encourage a quality urban
fishery.
Stream restoration techniques were applied to improve habitat in the most
degraded streams. Eight major urban stream restoration projects were
implemented to significantly improve almost 10 miles of river habitat. To
prevent future degradation, land use controls and stringent stormwater and
sediment practices were applied at new development sites in sensitive
watersheds, to minimize impact on stream systems.
Goal 3: Restore the spawning range of anadromous fish to historical
limits.
Annual migration of anadromous fish species had been stopped by as many as 25
unintentional man-made fish barriers along the lower portion of the Anacostia.
Removal of key fish barriers is important to expanding the available spawning
range for anadromou s fish; improvement of the quality of the watershed's
spawning habitat is also important. In the spring of 1991 a "bucket brigade"
was begun that manually transports fish over barriers so that they can imprint
the unique chemistry of the newly opened spa wning range, and return to the
same spots year after year.
Goal 4: Increase the natural filtering capacity of the watershed by sharply
increasing the acreage and quality of tidal and non-tidal wetlands.
Local agencies have been empowered with new authority to protect all non-tidal
wetlands, with a goal of no further net loss of wetlands within the watershed.
Numerous projects have been initiated for restoring degraded tidal and
non-tidal wetlands and ma rshes, and for creating hundreds of acres of new
wetlands.
Goal 5: Expand the forest cover throughout the watershed and create a
contiguous corridor of forest along the margins of its streams and rivers.
Riparian vegetation plays a critical role in maintaining stream water
quality, preventing streambank erosion, and providing aquatic and terrestrial
habitat. Extensive reforestation efforts have been implemented, both for upland
areas and riparian zones, often with local agencies being provided with both
trees and volunteers for tree planting. A new 1991 Maryland state law provides
local authorities with the power to require reductions in the amount of forest
cover lost during development, with specific mitigation requirements detailed
in tree ordinances, buffer criteria, and Critical Area programs. The ultimate
goal in the riparian reforestation efforts is to provide an unbroken forest
corridor from the tidal river to the uppermost headwater streams.
Goal 6: Make the public aware of their role in the Anacostia cleanup, and
increase their participation in restoration activities.
Many of the approximately 600,000 residents of the Anacostia watershed are
unaware that they live in the watershed, and do not perceive a connection to
the river. A strong public outreach program was therefore developed to raise
public awareness about th e problems of the Anacostia River and the ongoing
restoration efforts. The program includes a quarterly newsletter, sub-basin
coordinators, and educational publications and activities. Several
environmental groups have responded to public outreach initi atives with
cleanups, plantings, and stream walks. A Small Habitat Improvement Program was
developed for implementation of small-scale restoration projects by citizen
volunteers, and a number of tree-planting, wetland creation, storm drain
stenciling, an d stream cleanup projects have been completed.
Issues of Cost
The Anacostia Watershed Restoration program provided coordination for
spending by a large number of public and private organizations. Table 6-2, Summary of the Anacostia Restoration Blueprint,
is taken from the Draft 1992 Anacostia Restoration Team "Blueprint for the
Restoration of the Anacostia Watershed" (Metropolitan Washington Council of
Governments 1992 draft). The figures in the table are estimates for ca pital
and operating costs to be incurred over life of the program, and they provide
an example of the scale of projects required to restore a severely degraded
urban watershed.
The cost estimates are organized according to the watershed goals
established for the Anacostia River watershed. The table allows a rough
comparison of the relative costs for technology and construction intensive
projects (e.g., sewage treatment, combine d sewer overflow construction, other
point source controls) versus habitat restoration measures (e.g.,
bioengineering, best management practices, reforestation). While a precise
comparison is not possible it is clear that technology and construction obje
ctives are responsible for the largest percentage of the estimated costs.
The estimated total cost for the entire project (including $70 million
dollars for river dredging, sewer rehabilitation, reclamation, and other
activities not assigned to a distinct goal) is $115,600,000 in 1990 dollars.
Assuming a ten-year life span to f or the project, the annual cost per
household would be $68, given a population of 600,000 people, an average
household size of 3.5 people, and no outside financial assistance. A potential
measure of success for the Stewardship Goal (Goal 6) would be the w illingness
of Anacostia residents to pay this amount as an annual contribution towards
restoration of the watershed.
| Back to Chapter
6 |
|