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Alger Park Upland Low Impact Development and Stream Restoration
Project Significantly Improves Water Quality

Waterbody Improved The Alger Park Upland Low lmPact Development (LID) and

Stream Restoration Project is an example of DC's award-winning
watershed-based restoration approach. Before restoration, the stream running through Alger Park
was highly degraded and incised, with eroded sandy banks as high as 40 feet. The stream was added
to the 2008 Clean Water Act (CWA) section 303(d) list of impaired waters for multiple pollutants.
The District Department of Energy & Environment (DOEE) implemented a restoration project focused
on education and outreach, upland LID on both private and public space, and a large-scale stream and
wetland restoration project in Alger Park. This project is reducing volume and velocity of stormwater
entering the park, slowing flow within the channel, and improving in-stream water quality.

Problem

Located in southeast Washington, DC's Hilicrest
neighborhood, a smal! low-flow stream flows through
Alger Park and is a tributary to the Texas Avenue
tributary, which flows into the Anacostia River and
the Chesapeake Bay (Figure 1). The watershed drains
approximately 32 acres, including 7 acres in Alger
Park and 25 acres of mostly single-family homes and
roadways around the park. The neighborhood around
Alger Park is aptly named Hilicrest as it is steeply
sloped. Prior to development, the stream in Alger
Park was likely an Intermittent stream. Six stormwater
outfalls were constructed during the development
of the neighborhood to convey runoff Into the park's
stream. The upper 850 feet of the stream is steeply
sloped with sandy coastal plain soils. The combina-
tion of stormwater being directed at steeply sloped
sandy soils caused massive channel incision and bank
erosion. The total length of Alger Park is 1,541 feet;
pre-restoration calculations showed 100 tons of sedi-
ment leaving the site due to bank erosion.

Story Highlights

The Alger Park Upland LID and Stream Restoration
project is an award-winning comprehensive approach
to watershed restoration in an urban environment.
The project came to DOEE at the request of residents
who lived adjacent to the stream and expressed con-
cern about stream conditions. First, DOEE partnered
with the Hilicrest Community Civic Association hosting

Figure 1. I his restored stream flows through Alger Park
in southeast Washington, DC.

education and outreach events explaining to residents
how the stream became so degraded and what they,
as watershed residents, could do on their properties
to help restore the stream. Through living room talks,
speaking at community events, and door-to-door flyers,
DOEE reached all 132 property owners in the drainage
area with information about the RiverSmart Homes
Installed at least one stormwater practice on their
property (either rain garden, rain barrel, or shade tree).

During the early phases of project work, DOEE issued
a 30% design contract exploring two options for both
stream restoration and upland LID installations in
the public right-of-way draining into the park. The

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Figure 2. A green alley allows runoff to infiltrate.

The Alger Park project's success was achieved through
a two-part approach. First, the upland LID installations
treated stormwater runoff from over 200,000 square
feet of impervious surface (retaining 11,500 cubic
feet of stormwater) before flowing into Alger Park.
Second, using the Chesapeake Bay Program's protocols
for stream restoration pollutant load calculations,
the stream restoration work at Alger Park will reduce
677,384 pounds (lbs)/year (yr) of total suspended
solids, 991 Ibs/yr of total nitrogen, and 355 Ibs/yr of
total phosphorus. Temperature and dissolved oxygen
levels should also improve. Together, the upland LID
and stream restoration will significantly improve water
quality in both Alger Park and downstream receiving
waterbodies.

LID practices were installed in public-space, and 29 LID
practices were installed on private property (Figures 2
and 3). In 2019, the Alger Park Upland LID and
Stream Restoration Project received the Chesapeake
Stormwater Network's "Best Stream Restoration Award"
and "Best Urban BMP in the Bay Award (BUBBA)."

Results

Figure 3. This upland LID practice captures road runoff.

preferred design stream design alternative was then
contracted out separately for full designs, which
focused on a regenerative stream design for the upper
portion of the stream valley and a wetland/floodplain
reconnection approach to the lower portions of the
project area. Concurrently, the District Department of
Transportation issued a design contract for the LID to
be installed in the public right-of-way.

In 2017, restoration work began in Alger Park by first
filling the stream with a sand and wood chip mix,
followed by installing a series of weirs and cascades
to act as grade controls. Large pools between each
weir/cascade helped dissipate stream energy and
attenuate flow. In the lower area, the stream restora-
tion consisted of a series of vaiieywide grade control
structures that included buried logs to ensure high-
flow events would spread out over the entire wetland
complex. Micro-pools were created in the wetland
area to reduce energy and to create different types
of inundation for a variety of native wetland plants, in
total, the project restored over 1,541 feet of stream,
created approximately 0.5 acres of wetland, and sta-
bilized six stormwater outfalls. In addition, 29 upland

DOEE contracted with the Metropolitan Washington
Council of Governments, an independent nonprofit
group, to perform rapid stream assessment survey
monitoring on implemented stream restoration
projects. Alger Park stream monitoring began in 2021
following completion of the 2017 project. According
to the Macroinvertebrate Benthic Index of Biological
Integrity (BIBI) Study, scores in April 2021 were slightly
higher than in April 2015, indicating improvement (BIBI
ranking changed from a very poor score of 1.6 to a
poor score of 2.7). Further annual or biennial surveys
are recommended to determine if improvement is a
trend for the post-restoration period.

Partners and Funding

DOEE worked with the Hillcrest Community Civic
Association on community outreach and education.
DOEE contracted with LimnoTech and Biohabitats for
design work and Environmental Quality Resources
for construction work. DOEE received project fund-
ing from DC's Bag Law Fund, the National Fish and
Wildiife Foundation, the U.S. Environmental Protection
Agency's (EPA's) Section 319 Program, the EPA
Chesapeake Bay implementation Grant, and EPA's
Clean Water State Revolving Fund.

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U.S. Environmental Protection Agency
Office of Water
Washington, DC

EPA 841-F-22-001R
September 2022

For additional information contact:

Josh Burch
DOEE

202-734-9527

josh.burch@dc.gov

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