Section 319
NDNPDINT SOURCE PROGRAM SOGGESS STORY
Community-led Sediment Control Projects Restore Recreational
Uses to Lake and Beach
\A/ t h H I H Beginning in the 1970s, recreational uses at Manchester's Crystal
VV3I6rDOOy irnprOVGQ L^ were affected by chronic water quality problems including
elevated levels of sedimentation with accompanying nutrient loading and weed infestations. New
Hampshire Department of Environmental Services (NHDES) placed both Crystal Lake and Crystal Lake
Beach on the 2006 303(d) list of impaired waters. In the mid-1990s, the City of Manchester and Crystal
Lake Preservation Association (CLPA) began addressing stormwater problems using structural and non-
structural best management practices (BMPs). Manchester implemented sediment control measures,
and CLPA organized outreach and monitoring efforts. As a result of these and other measures, Crystal
Lake and Crystal Lake Beach are no longer listed as impaired for primary or secondary contact recre-
ation on New Hampshire's 2008 303(d) impaired waters list.
Problem
Crystal Lake is a 19-acre lake (Figure 1) in New
Hampshire's largest city, Manchester. Much of the
200-acre watershed is comprised of residential
neighborhoods, all served by a municipal sewer
system. Shoreline development includes seasonal
camps, year-round homes, and the city's only
municipal beach. Crystal Lake has no surface
tributaries; rather it is a seepage lake, fed primarily
by groundwater flow and stormwater runoff.
Historically, untreated runoff deposited large
amounts of sediment into the lake. The sediment
deposition and associated nutrients led to shallow
water depths, algal blooms, reduced water clarity,
and excessive aquatic vegetation growth, especial-
ly adjacent to the city beach. Manchester's Parks
and Recreation department began reporting these
issues and their impact on recreation in 1973. The
frequent algal blooms, which could be attributed
in part to phosphorus transported and retained in
sediments, caused low dissolved oxygen levels and
decreased biodiversity.
In 1985 NHDES completed a Diagnostic and
Feasibility Study which documented that the main
impact to water quality at Crystal Lake resulted
from untreated stormwater runoff. The study found
that sediments, nutrients, bacteria, and heavy met-
als were present in elevated levels. The study also
noted that deposited sediment was a main com-
ponent of a phosphorus rich, unconsolidated muck
layer that was up to 25 feet deep in spots. In 2006,
NHDES added Crystal Lake and Crystal Lake Beach
to New Hampshire's section 303(d) impaired waters
Figure 1. Crystal Lake beach in July 2008.
list for primary and secondary contact recreation
due to sedimentation/siltation.
Project Highlights
In 1994 CLPA received a U.S. Environmental
Protection Agency (EPA) section 319 grant to
engage local residents and begin restoration efforts.
CLPA organized one of New Hampshire's first storm
drain stenciling programs, delivered stormwater
pollution information door to door, constructed an
information kiosk at the beach, and, with technical
assistance from DES staff, measured water quality
benefits of street sweeping. CLPA, NHDES, and the
city cooperated on a 1996 EPA section 104(b)(3)
project to install six StormTreat® systems to address
the first of two large stormwater outfalls. Another
section 319 grant in 2004-2005 provided funds for
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Figure 2. A vegetated swale built to treat road and
parking lot runoff before it enters Crystal Lake.
the city to construct BMPs at the second outfall
including deep sump catch basins, a stormwater
baffle tank, lateral drains, and vegetated swales
(Figure 2). As part of the non-federal match for the
grant, the city dredged the beach to remove historic
sediment and weed accumulations.
CLPA received two additional section 319 grants
to help fund outreach and capacity-building for
local water quality protection. Volunteers from
CLPA with assistance from NHDES Volunteer Lake
Assessment Program, and Manchester's Urban
Ponds Restoration Program continue to monitor
water quality at Crystal Lake. The city sweeps the
roads in the watershed at least three times annu-
ally, and sweeps the beach parking area five times
annually. The city implements a NPDES Phase II
Stormwater Plan that includes semiannual inspec-
tion of catch basins and treatment units around the
lake, with clean-outs performed at least annually.
Results
Crystal Lake has no remaining untreated
stormwater outfalls. The city's dredging project
removed 121.5 tons of historic sediment, which
improved water depth and reduced aquatic weed
growth at the beach. Partners implemented
structural and non-structural BMPs to prevent
sediment re-accumulation. Since 2005, the city has
removed on average 9.5 tons of sediment annually
from catch basins and treatment devices. Additional
sediment removal is achieved with the vegetated
swale and street sweeping, but those amounts are
not tracked. Street sweeping also reduces phospho-
rus and metal inputs to the lake (Figure 3). Because
of these projects, primary and secondary contact
recreation is no longer impaired by sedimentation/
siltation. These impairments were removed from
NH's 2008 section 303(d) list; however, Crystal Lake
remains listed for dissolved oxygen and mercury.
Partners and Funding
This project involved cooperation of CLPA,
Manchester Urban Ponds Restoration Program,
Manchester Parks Recreation and Cemeteries
Department, Manchester Environmental Protection
Division, NHDES Watershed Management Bureau,
and EPA. The association of local volunteers, along
with city, state, and federal staff worked coopera-
tively throughout the project period and continue to
coordinate maintenance and monitoring activities.
The 1985 Diagnostic and Feasibility study was
funded through an EPA section 314 Clean Lakes
grant with in-kind services provided by the state.
From 1994 through 2005, EPA provided a total of
$111,845 to facilitate restoration work at Crystal
Lake. In 1994, 1997, and 2003, CLPA used a total
of $14,362 in section 319 funds and $9,557 in
matching funds to complete outreach and educa-
tion activities related to nonpoint source pollution
and water quality monitoring. In 1996 CLPA used
$24,000 in section 104(b)(3) funds and $36,000
in matching funds to install the initial series of
structural BMPs. From 2003 to 2005, the city used
$73,483 in section 319 funds and $85,199 in match-
ing funds to construct additional BMPs. The city
continues to fund BMP maintenance and laboratory
costs for water quality samples. CLPA continues
to provide additional funding and in-kind services
through volunteer monitoring activities.
Street Sweeping: Percent Removal of Contaminants
m
Copper
Turbidity
TSS Phosphorus
Figure 3 . Data from samples collected at stormwater
outfalls, before and after street sweeping, were compared
to determine contaminant removal efficiencies.
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U.S. Environmental Protection Agency
Office of Water
Washington, DC
EPA841-F-09-001DD
September 2009
For additional information contact:
Barbara McMillan
Watershed Outreach Coordinator
New Hampshire Department of Environmental
Services
603-271-7889 • Barbara.mcmillan@des.nh.gov
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