NPDES / Erosion and Sedimentation Control Project
Erie County Conservation District
Basin Program Funds:
Measurable increases in urban development in Erie County, Pennsylvania and changes
to the state's National Pollution Discharge Elimination System (NPDES) permit
process, created a need for public awareness of nonpoint source pollution and
appropriate best management practices for both permitted and non-permitted earth
The Erie County Conservation District is developing a 35 acre environmental
education park in Erie, Pennsylvania. "Headwaters Conservation Park" is located
in the upper watershed of Mill Creek which discharges into Presque Isle Bay
on Lake Erie. The park is an example of how conservation and industrial expansion
can co-exist. Over its long term development, the park will be used to demonstrate
a variety of conservation best management practices.
The NPDES/Erosion and Sedimentation Control Demonstration Project used a building
site next to the park as an opportunity to demonstrate non-traditional best
management practices (BMP) for nonpoint source pollution control during construction.
The Conservation District modified a required storm water facility to serve
as a sediment trap during the construction phase of the project with the assumption
that sedimentation control would be more efficient, cost effective and timely.
The project team then used the information gleaned to hold a NPDES workshop
for local contractors, developers, engineers and municipal officials.
The project team developed a storm water management plan which
was submitted for township approval. They determined the required capacity for
the sedimentation trap and outlet structure. While awaiting approval of the
storm water management plan, the team inspected the construction site weekly
and installed temporary best management practices including a silt fence, vegetative
buffers along the creek and filter strips.
Once the storm water management plan had been approved, the team
excavated the sediment basin. Sedimentation basins capture and store eroded
soil from effluent leaving a disturbed surface site before the water is discharged
into the environment. The amount of sediment released is controlled by the basin's
outlet structure. Working in conjunction with the University of Pennsylvania,
Department of Agricultural and Biological Engineering, the project team installed
a Faircloth skimmer as a temporary trap outlet device. Skimmers allow eroded
material to settle to the bottom of a sedimentation basin while drawing out
and releasing clean water. Project personnel dug an interceptor channel which
diverted sediment-laden runoff from throughout the building site to the sedimentation
trap. They also seeded and mulched the pond embankment and surrounding area.
The project team inspected the site weekly in order to monitor
the basin's efficiency and ensure that the skimmer operated properly. They were
also able to identify and correct problems as they arose. These included breaches
to the diversion berm which required the construction of a separate, temporary
The team developed an educational brochure outlining the project
and how it applied to NPDES regulations for a best management practice (BMP)
workshop. The workshop introduced township officials and engineers, as well
as consultants and developers to a newly published manual, "Pennsylvania BMP
Manual for Developing Areas." The workshop also addressed recent changes to
the NPDES, use of multi-purpose BMPs, and a summary of the sedimentation basin
project and findings.
One of the goals of this project was to persuade developers to use non-traditional,
mulitple use BMPs for projects involving earth disturbance. Within the first
several months after the workshops two consultants expressed interest in obtaining
a skimmer, and numerous plans submitted to the township have proposed using
the required storm water pond as a temporary sediment trap during the construction
Additionally, soil saving calculations for both the temporary
sediment trap and the sedimentation basin indicate that the basin was much more
efficient. The temporary sediment trap accumulated 20 tons of soil while approximately
31 tons of soil were displaced. This meant a net loss of 11 tons of soil. The
sedimentation basin accumulated all but one ton of the 39 tons of soil diverted
into the basin.
Contact: LeRoy Gross, (814) 796-4203