SAW-2024-00114 Additional Information 13March2024

The PCN application did not include any plans to
extend the existing bypass culvert to Cove Creek.
The current placement of this outfall pipe is
causing erosion of the stream bank along Cove
Creek and may result in the destabilization of the
impoundment structure. Further, the placement of
this outfall does not comply with the condition of
the requested nationwide permit. Please provide
plans and description that illustrated how the
placement of this outfall will be corrected
1. Install a 45 degree 18” corrugated culvert pipe
at the end of the existing 60’ long culvert pipe that
serves to divert 80” of the water flowing from the
UT Unnamed tributary into the this pipe.
2. Install a 10’ section of 18” corrugated culvert
pipe to direct the flow of the water directly into the
basin below.
3. Install another 45 degree 18” corrugated culvert
pipe at the end of 10’ section of corrugated pipe
directing the flow downward from the existing 18”
long culvert pipe that serves to divert 80% of the
water directly into cove creek.
1. The recently submitted PCN does
not include plans depicting the location
design of the pond’s outfall structure.
The overflow from the pond is currently
overtopping the impoundment
structure and running down a sheet of
plastic draped over the impoundment
structure. This is resulting in erosion of
the toe of the impoundment. Please
provide a detailed description and
plans for the design and installation of
Install a 46” wide waterfall diffuser for the purpose of dispersing the
centralized flow of the incoming water flow. Install a secondary 32” wide waterfall diffuser to further disperse the flow
of water. Both diffusers and be fitted with flat rocks on the exposed surface and on the front edge to disguise the
plastic and to blend with the rock dam.

https://www.amazon.com/EasyPro-Pond-
Products-UWD23-Waterfall/dp/
B01CNT1UZE/ref=sr_1_1?
crid=3HF5P8W4N6Y9A&dib=eyJ2IjoiMSJ9.k
NiTItlTxBefcDMB3lzERUQJ624pYT_-
JlgmaMEeqXJl2uCBfR7mYjq2urHR00t3vgaq
Wx_COoB8U847Ju4NqH8AskQyFTXvM8mnu
aAWyoiUyeJGHmxs7UGU1XB1lGDIzoiCmuo
ajoGCBHtqmLL7HvL4XY8NMC75EtnyIPm-
ZoFHB28L3dERpLXfc9kEFpMklV2zywjWQ-
DmWM_T-8BPBwUQBxsPJsxcv71WmAQ4b4
4-
WM7SekAidBKRv_GF2i92cBw2FUJaptCP8q
yVdQTj5FflOectLOJiPWJBNuaLlc8.QQc0H5S
sB5Ks8j8VKClwgSAc_vlihQUEEAqMemEuaQ
4&dib_tag=se&keywords=outdoor+waterfall+
diffuser&qid=1709877849&sprefix=outdoor+
waterfall+diffuser,aps,98&sr=8-1&th=1
The resulting in erosion of the toe of
the impoundment can be remedied by
filling the basin with boulders to
disperse the water coming from both
the diverter pipe and the pond
waterfall.
The amount of flow entering the pond
exceeds the amount of flow entering the
bypass culvert. Please note, in stream
diversions must allow for the ongoing
discharge of base flow from the UT into
Cove Creek. This base flow discharge may
occur via a bypass channel/culvert, low-flow
orifice through the impounding structure, or
a combination of both a by-pass channel/
culvert and low-flow orifice. Please provide a
description, stream flow calculations, and
plans explaining base flow amount and how
it will be routed into Cove Creek.
With the constantly fluctuating base flow of the UT the goal of insuring that 20% of the overall flow would be have to
continuously monitored. By removing 20% of the bolt on corrugated pipe cap it insures that no matter how much or
how little water flow exists from the contributing Unnamed Tributary, only 20% of that will enter the capped pipe
feeding the pond. The remaining portion of water flow will divert to the pipe feeding Cove Creek.

To insure uninterrupted and even water flow from the Tributary the basin between the two corrugated pipes will be
cleaned out and dug down below the base level of the two pipes and lined with the pond liner. This insures that water
flow into the pipes is fed by overflow from the basin thereby preventing debris from interfering with the continuous
water flow.

This link describes the specifications for the cap. https://s3.amazonaws.com/s3.supplyhouse.com/product_files/
Polylok-3007-HDC-Submittal-Drawing.pdf

4A4
4. Replace all plastic mesh with mesh constructed of biodegradable material:

1 All Excelsior erosion control matting will be removed. 2. The plastic liner will be removed from the waters edge of
the pond. 3. A shelf will be cut back into the bank and lined with rocks to hide the plastic liner. 4. Creeping phlox
seed will be sewn into the soil. 5. Three rolls of double net cotton laced straw erosion matting will be placed
alongside the 2 sides of the pond that do not encompass the bank to insure that the seeds germinate and the soil
stays in place.

4A. The sloped pond bank topside. 1. Two 12” x 12” deep wide trenches will be cut into the pond bank from the
top of the bank to the edge of the creek. 2. Creeping phlox seeds will be sewn into the soil. 3. An 8’ wide x 112’ log
roll of double netted straw matting will be rolled onto the upper portion and the sloped bank. 4. Two foot Oak
stakes will be hammered into the trenches on the top of the bank to hold the matting in place. 4. Two foot oak
stakes will be hammered along the top edge of the sloped bank every two feet to hold the matting into place.
Trench w/stakes
Trench w/stakes

5
5. Stream Bank Stabilization:

To better stabilize the existing bank we must remove the silt fence and reduce the slope of the bank.

1. The existing matting will be removed from the top side of the pond bank. 2. Large boulders will be placed between the side of the slope
adjoining the creek and the existing edge of the creek. 3. The edge of the top side of the pond facing the creek will be softened and sloped. 3A.
The silt fence can be placed along the creek side edge of the large boulders that will line the edge of the creek. 4. Fill that had be temporarily
placed alongside the bank at the shallow end of the pond will spread between the top sloped edge of the pond and the large boulders that will
line the edge of the creek. 5. Three 10 yard loads of topsoil will be spread onto the now sloped rocky bank. 6. Four 12” x 12” deep wide
trenches will be cut into the pond bank vertically every 20’. 7. An 8’ wide x 112’ log roll of double netted straw matting will be rolled onto the
lower sloped portion of the bank. 8. Two foot Oak stakes will be hammered into the trenches on the sloped portion of the bank to hold the
matting in place. 9. Two foot oak stakes will be hammered along the top of the matting placed about half way down the sloped bank every two
feet to hold the matting into place. 10. 25 live stakes or 1 gallon Dog Hobble or erosion control evergreen plants will be planted every 3 feet
upon the 70’ by an averaged 4.5’ height in a triangular pattern bank to insure stabilization. See Page 2 for plant placement design..

5
Dam end of the

embankment is 8.5’ tall

Well House end of the
embankment is 4’ tall
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