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CONNECTICUT
Nonpoint source management in Connecticut has evolved into a well-balanced,
comprehensive program involving numerous government and nongovernment agencies
and organizations. The Connecticut Department of Environmental Protection (CT
DEP) is the lead agency for nonpoint source management, responsible for
administering the annual section 319 grants. The CT DEP Nonpoint Source Program
has developed an effective network of federal, state, and local agencies
including the USDA Soil Conservation Service (SCS), state agriculture and
transportation agencies, and soil and water conservation districts (SWCDs).
Erosion Problems Checked Through Stabilization Partnership
In September 1989, the Town of East Windsor asked SCS and Hartford County
SWCD to investigate several erosion problems near Rockville Road that were
depositing large quantities of sediment on the road and in a small -
watercourse leading to nearby Ketch Brook. Ketch Brook is a tributary to the
Scantic River--identified in the state's NPS Assessment and Management Plan as
a high priority for NPS management--and, in turn, a tributary to the
Connecticut River. The SCS and Hartford County SWCD determined that part of the
problem was erosion of a nursery stock field sloping toward Rockville Road. The
field had lost much of its topsoil, which had been washed downhill onto the
road and through a culvert into a watercourse leading toward Ketch Brook. The 4
to 6 inches of sediment on a stretch of Rockville Road presented a driving
safety hazard, and caused excessive scouring and destabilization of the -
watercourse banks.
Another watercourse had been clogged by sediment from nearby fields and
roads, causing the stream to leave its channel, flow across a field, and
deposit sediment in wetlands adjacent to Ketch Brook. The farm operator had
attempted to fill the newly formed gully, but the fill material had also washed
out, depositing even more sediment downstream in the wetlands.
Using the Universal Soil Loss Equation, SCS estimated the annual soil loss
from the two fields, totaling 40 acres, at more than 1,000 tons, with erosion
expected to continue. The sediment delta in the wetland was approximately 30
feet wide by 200 feet long, and 18 inches deep in some areas. These sediments
were harming both water quality and riparian habitat. Sediment loads to the
watercourses leading to Ketch Brook were contributing to eutrophication,
organic enrichment/dissolved oxygen depletion, and siltation downstream in the
brook and, particularly, in impoundments on the brook such as Windsorville
Pond. While the natural wetland habitat exhibits diverse vegetation, including
cinnamon fern and various mosses, the sediment delta supported only skunk
cabbage and jewel weed. In addition, the red maple tree canopy above the
sediment delta showed extreme stress, compared to nearby healthy trees. To help
correct the erosion and sediment problem, the Hartford County SWCD received a
FY 1990 section 319 grant of $75,000 from CT DEP for the Ketch Brook Watershed
Land Treatment Demonstration Project. The 319 funds were matched by a
contribution of $192,100 from a coalition including CT DEP, the Town of East
Windsor, the farm operator, SCS, and the USDA Agricultural Stabilization and
Conservation Service (ASCS).
The primary goal of the project was to reduce loading of sediment,
agricultural nutrients, and pesticides to the watercourses and wetlands leading
to Ketch Brook. A secondary goal was to demonstrate the effectiveness of
agricultural best management practices to encourage widespread use throughout
the Ketch Brook and Scantic River watersheds.
The work plan included developing a watershed management plan with a land
use inventory and assessment of other NPS problems in the Ketch Brook
watershed. The primary focus, however, was to demonstrate structural and
nonstructural erosion and sediment control BMPs at the Rockville Road site.
Structural practices were aimed at halting and stabilizing the accelerated
erosion in the agricultural fields and streambank channels. The main practice
was to construct stone-lined (riprap) waterways to reduce flow velocities and
protect the highly erosive streambanks. Nonstructural practices emphasized
cultural activities in the watershed, including cover cropping, permanent
seeding, and cross-slope row cultivation. In addition to the Hartford County
SWCD, the project coordinator, the public/private partnership included
technical assistance from SCS; in-kind construction, financial assistance, and
permits from the Town of East Windsor; cost-share assistance to the farm
operator from ASCS; and in-kind construction and cost-share for land treatment
from the farm operator. In addition, CT DEP provided technical assistance and
helped secure financial assistance through the Flood and Erosion Control Bond
Commission. Several local contractors provided advice on construction
alternatives. This assistance was vital to developing a feasible plan and
design. Construction of structural practices began in September 1991 and was
completed the following spring. Implementation of nonstructural practices began
in summer 1991 and are being maintained under a long-term agreement with the
farm operator. The Hartford County SWCD has since received additional 319
funding for the Scantic River Watershed NPS Management Project, including
$65,000 in FY 1993 funds to correct other erosion problems in the Ketch Brook
subwatershed.
All the project sponsors and local residents consider the project a
success. The most obvious result is the reduced sediment loading to Ketch Brook
and its wetlands. Soil erosion has been reduced from over 2,000 tons of
sediment per year to less than 120 tons per year. The damage to the red maple
swamp has been reversed, with visible improvements to the wetland habitat. The
water quality improvement prompted one local angler to complain about decreased
fishing because of the water's improved clarity. Before the project, sediment
loading caused turbidity in the water column, forcing fish to feed nearer the
surface and making them easier to catch.
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