20210775 Ver 1_UPDATED "approved" outfall_20211124

Strickland, Bev
From: Brent Cowan <[e-mail]>
Sent: Tuesday, November 23, 2021 4:41 PM
To: Johnson, Alan; Heath Caldwell
Subject: RE: [External] Weddington Glen Subd. (Union County)
Attachments: 16157-B-BMP-05.1-BMP 2.pdf; GEN_EC_BRO_3.20.pdf; EC_RMX_MPDS_VMC350_
1.19.pdf
CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
Report Spam.
Good afternoon Alan,
Attached is a revised sheet C5.1 for BMP #2 showing the swale reintroduced through the buffer. To help
promote water quality, I have removed the rip rap and specified a grass swale with a permanent liner that
allows grass to grow thru it while the liner adds extra stability to swale to prevent erosion. I have also
softened the angle (or turn) of the swale by adding a larger swooping curve, and have the alignment of the
new swale pointed in the same direction of the receiving swale. A note has been added to terminate the
swale above the ordinary high water mark to avoid impact to the receiving channel. Also attached are some
pdf of manufacturer's literature on the C350 permanent liner.
I think this is a better design to manage the flow from the BMP rather than allow the water to flow through
the buffer uncontained as the latter scenario will result in erosion and long term damage to the buffer. Please
review and let me know if have any questions or comments on the grass swale design. Upon your agreement,
I will sign and issue officially.
Thanks,
Anthony Brent Cowan, P.E., LEED A P
The Isaacs Group, P.C.
8720 Red Oak Blvd., Ste. 420
Charlotte, NC 28217
P: 704-227-9402 F: 704-527-8335
Email: [e-mail]
Web: www.isaacsgrp.com
From: Johnson, Alan <[e-mail]>
Sent: Monday, November 22, 2021 9:29 AM
To: Heath Caldwell <[e-mail]>; Brent Cowan <[e-mail]>
Subject: RE: [External] Weddington Glen Subd. (Union County)
I am here
You may want to resend the options that are being discussed
1

DWR
Division of Water Resources
Alan D Johnson — Senior Environmental Specialist
NC Dept. of Environment & Natural Resources (NCDENR)
Division of Water Resources - Water Quality Regional Operations
610 East Center Ave., Suite 301, Mooresville, NC 28115
Phone: [phone] Fax: [phone]
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be
disclosed to third parties unless the content is exempt by statute or other regulation.
From: Heath Caldwell [mailto:[e-mail]]
Sent: Monday, November 22, 2021 9:19 AM
To: Johnson, Alan <[e-mail]>; Brent Cowan <[e-mail]>
Subject: Re: [External] Weddington Glen Subd. (Union County)
CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
Report Spam.
Alan/Brent-
Available to jump on a call today and work this out?
On Fri, Nov 19, 2021 at 2:17 PM Johnson, Alan <[e-mail]> wrote:
Given that the outfall is comeing from a treatment facility, it appears it is approvable to issue
the conveyance through the buffer. But I am having a hard time, allowing the water going
straight to the stream channel. The purpose of the buffer also allows to spread out the affect
of the water. They want to riprap a conveyance all the way to the stream.
Have they considered a partial conveyance that then spreads the water to sheet flow. Have
they tried a vegetative grass swale or enhance grass swale or considered a geogrid
"grass" swale
2

DWR
Division of Water Resources
Alan D Johnson — Senior Environmental Specialist
NC Dept. of Environment & Natural Resources (NCDENR)
Division of Water Resources - Water Quality Regional Operations
610 East Center Ave., Suite 301, Mooresville, NC 28115
Phone: [phone] Fax: [phone]
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be
disclosed to third parties unless the content is exempt by statute or other regulation.
From: Heath Caldwell [mailto:[e-mail]]
Sent: Friday, November 19, 2021 2:10 PM
To: Johnson, Alan <[e-mail]>
Subject: Re: [External] Weddington Glen Subd. (Union County)
CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
Report Spam.
Any updates here Alan?
On Wed, Nov 17, 2021 at 8:17 AM Johnson, Alan <[e-mail]> wrote:
I am waiting for another couple of comments.
3

DWR
Division of Water Resources
Alan D Johnson — Senior Environmental Specialist
NC Dept. of Environment & Natural Resources (NCDENR)
Division of Water Resources - Water Quality Regional Operations
610 East Center Ave., Suite 301, Mooresville, NC 28115
Phone: [phone] Fax: [phone]
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be
disclosed to third parties unless the content is exempt by statute or other regulation.
From: Heath Caldwell [mailto:[e-mail]]
Sent: Wednesday, November 17, 2021 7:57 AM
To: Johnson, Alan <[e-mail]>
Subject: Re: [External] Weddington Glen Subd. (Union County)
CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
Report Spam.
Hey Alan -
Any update from Jim? Time for a call this morning? I can call in with the engineer if that works?
On Tue, Nov 16, 2021 at 10:04 AM Johnson, Alan <[e-mail]> wrote:
4

Jim, given that this is in the 6 mile creek (subject to the Goose Creek Buffer Rule) is the
outlet through the buffer allowed.
tend to say stay out of the buffer. And spread the water out, so further remediation can
occur as discharge flows through the buffer
DWR
Division of Water Resources
Alan D Johnson — Senior Environmental Specialist
NC Dept. of Environment & Natural Resources (NCDENR)
Division of Water Resources - Water Quality Regional Operations
610 East Center Ave., Suite 301, Mooresville, NC 28115
Phone: [phone] Fax: [phone]
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may be
disclosed to third parties unless the content is exempt by statute or other regulation.
From: Heath Caldwell [mailto:[e-mail]]
Sent: Tuesday, November 16, 2021 9:30 AM
To: Johnson, Alan <[e-mail]>
Cc: Farkas, Jim J <[e-mail]>
Subject: Re: [External] Weddington Glen Subd. (Union County)
CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
Report Spam.
5

6-mile on this one Alan.
On Mon, Nov 15, 2021 at 1:58 PM Johnson, Alan <[e-mail]> wrote:
For clarity, was this buffer located in the 6 mix Creek or Waxhaw creek watershed? If so,
would that change the applicability of SW BUA issue as related to the buffer rule
requirement
DWR
Division of Water Resources
Alan D Johnson — Senior Environmental Specialist
NC Dept. of Environment & Natural Resources (NCDENR)
Division of Water Resources - Water Quality Regional Operations
610 East Center Ave., Suite 301, Mooresville, NC 28115
Phone: [phone] Fax: [phone]
E-mail correspondence to and from this address may be subject to the North Carolina Public Records Law and may
be disclosed to third parties unless the content is exempt by statute or other regulation.
From: Farkas, Jim J
Sent: Monday, November 15, 2021 1:55 PM
To: Brent Cowan <[e-mail]>; Johnson, Alan <[e-mail]>
Cc: Heath Caldwell <[e-mail]>
Subject: RE: [External] Weddington Glen Subd. (Union County)
6

I'd just like to add that post -construction stormwater doesn't necessarily review buffer impacts or make
determinations as to whether a buffer impact is acceptable or not. In this situation, we did not have an issue
with (and approved) the riprap lined swale since the riprap is not considered BUA and met all of our design
requirements for outlet stability.
Jim Farkas
Environmental Engineer
North Carolina Department of Environmental Quality
Division of Energy, Mineral, & Land Resources — Stormwater Program
512 N. Salisbury Street
1612 Mail Service Center
Raleigh, NC 27699-1612
[phone]
[e-mail]
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
Based on the current guidance to minimize the spread of COVID-19, the Department of Environmental
Quality has adjusted operations to protect the health and safety of the staff and public. Many employees are
working remotely or are on staggered shifts. To accommodate these staffing changes, all DEQ office
locations are limiting public access to appointments only. Please check with the appropriate staff before

visiting our offices, as we may be able to handle your requests by phone or email. We appreciate your
patience as we continue to serve the public during this challenging time.
From: Brent Cowan <[e-mail]>
Sent: Monday, November 15, 2021 1:17 PM
To: Johnson, Alan <[e-mail]>
Cc: Heath Caldwell <[e-mail]>; Farkas, Jim J <[e-mail]>
Subject: [External] Weddington Glen Subd. (Union County)
CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment
to Report Spam.
Good afternoon Alan,
The Weddington Glen subdivision is in Union County, Town of Weddington. NCDEQ approved the 401
wetlands permit on 8/31/2021 under DWR #21-0775. During the review and approval of this permit you
had commented to our wetlands consultant Heath Caldwell with WEPG that the riprap swale receiving
discharge from wet pond BMP #2 should be removed since it went through a creek buffer. This swale was
removed as directed and the permit issued. However, during permitting of the Minor Modification of the
SW permit with the SW group in Raleigh, it was noted that the swale was removed from the original design
and a comment has been issued by Jim Farkas to prove the flow from the pond through the buffer is
stable. I have been unable to provide a calc. showing stable conditions due to the high flows and steep
receiving terrain of 10%, and this email is to request that this swale be added back per the original design
for the following reasons.
• The original Stormwater permit issued by NCDEQ (permit no. SW3170802) on 10/16/2017 showed
the riprap swale as an approved impact to the buffer.
• Conventional engineering and permitting practice is to allow stormwater conveyances (pipe and/or
swale) through buffers for larger BMPs since direct discharge of concentrated water into upland
areas w/out drainage features will cause erosion, especially on terrain with moderate to severe slope
such as this project (we have 10%).
• Even with level spreaders to handle smaller storm events, bypass swales are allowed to be installed
through the buffer to accommodate larger storm events. This is discussed in MDC #2 in the level
spreader chapter C-9 of the State's stormwater BMP manual.
In summary, I would like to request that the plans be amended to show the rip rap swale through the stream
buffer as per the originally approved stormwater management plan. I believe this swale will provide better
8

long term stability to both the buffer and receiving channel No impact to the receiving channel would be
proposed as the design would show termination of the swale at or above the normal high water mark.
Thank you for your consideration.
Current layout
,WIDTI4=10_
ELI�fi4.21
Originally approved layout with Swale through Buffer
9

LIPS SHALB 0
GREATER THAN 4:1 IN
DUE ENERGY EASEMENT
Thanks,
Anthony Brent Cowan, P.E., LEEDR AP
M The Isaacs Group, P.C.
8720 Red Oak Blvd., Ste. 420
10

Charlotte, NC 28217
P: 704-227-9402 F: 704-527-8335
Email: [e-mail]
Web: www.isaacsgrp.com
Heath Caldwell
Wetlands & Environmental Planning Group
Leonard S. Rindner, PLLC
www.wetlands-epg.com
704.999.5279
Heath Caldwell
Wetlands & Environmental Planning Group
Leonard S. Rindner, PLLC
www.wetlands-epg.com
704.999.5279
11

Heath Caldwell
Wetlands & Environmental Planning Group
Leonard S. Rindner, PLLC
www.wetlands-epg.com
704.999.5279
Heath Caldwell
Wetlands & Environmental Planning Group
Leonard S. Rindner, PLLC
www.wetlands-epg.com
704.999.5279
12

DWR
DhBlon of Water Resources

D_E Q�

r 2'-0' 7

. EL. 66 .00 i0 L.
—ia M. W.S.. §9:50 �
_ OP.1. 9'74
22,
-�_ CLASS � � ■
Rli' R PRON \
RIP -CHA—EL \� ��
111S
IIIS
-- it / �r�.�•� t
KE PO wN
ESMT
L P AL2`-0" �
GREATERER THANN 4:1 IN
DUKE ENERGY EASEMENT