NCWRC Min. Flow Email 1-26-23

Moore, Andrew W
From: Leslie, Andrea J
Sent: Thursday, January 26, 2023 8:16 AM
To: Adam Tripp
Cc: Moore, Andrew W; Tarver, Fred; Stancil, Vann F
Subject: RE: USGS response to DWR USGS Low Flows request # 2023-250 (dated 2022/12/03) for Bearwallow
Branch Madison County ... RE: [EXTERNAL] Low -flow request approval
Hi Adam,
Fred, Vann, and I met to consider options for minimum flows in the bypass reach. If the
trout farm was a new proposed operation, we would recommend that 80% of the flows be
maintained in the bypass reach for ecological function. However, as the farm is in place and
now has a NPDES permit, and it's sited on a small stream, we recognize that this is a non-
starter. Our records indicate that there are rainbow trout downstream but not upstream of
the farm; this species is culturally important but non-native. We therefore recommend
maintaining 7Q 10 flows in the bypass reach as described below:
-Winter (November to March): maintain a minimum of 0.25 cfs; if incoming flows are less
than 0.25 cfs, then the total volume of incoming flow will be sent to the bypass channel
Summer (April to October): maintain a minimum of 0.17 cfs; if incoming flows are less than
0.17 cfs, then the total volume of incoming flow will be sent to the bypass channel
We didn't draw conclusions about the various weir options you have presented, but it is
important to ensure that anything constructed should not function as a barrier to aquatic
movement.
Can you forward the NPDES permit so we can look at that?
Andrea
Andrea Leslie
Mountain Habitat Conservation Coordinator
NC Wildlife Resources Commission
645 Fish Hatchery Rd., Building B
Marion, NC 28752
828-803-6054 (office)
828-400-4223 (cell)
www.ncwildlife.orLY
Get NC Wildlife Update delivered to your inbox from the N.C. Wildlife Resources Commission.
Email correspondence to and from this sender is subject to the N.C. Public Records Law and may be disclosed to third parties.

From: Adam Tripp <[e-mail]>
Sent: Tuesday, January 24, 2023 2:56 PM
To: Moore, Andrew W <[e-mail]>
Cc: Tarver, Fred <[e-mail]>; Leslie, Andrea J <[e-mail]>; Stancil, Vann F
<[e-mail]>
Subject: RE: USGS response to DWR USGS Low Flows request # 2023-250 (dated 2022/12/03) for Bearwallow Branch
Madison County... RE: [EXTERNAL] Low -flow request approval
CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
Report Spam.
All,
Good speaking with you this morning. I have queried the trout farm on what their minimum water intake volume is and
will get back to you with that information. As requested, I have attached a map showing hydrology and a V-Notch Weir
sketch with descriptions below. After preparing the sketch and running some calculations, I realized, we may be better
off with a Rectangular Contracted Weir, as described below:
• Aerial and Hydrology Map- These maps show the approximate intake and discharge location. There are two
small streams shown on the NC-1Map hydrology layer entering the stream in between the intake and discharge
locations. The groundwater supplied waterfall is located roughly in between these streams on river right. So,
there are multiple contributions to the stream in between the intake and discharge. I am having some figures
drawn up with more detail and will share those when available.
• V-Notch Weir Sketch — This preliminary sketch shows a potential design for measuring flow and includes a
buried foundation plate that will be below about 0.5 to 1.5 feet of cobble and boulders on the front and back.
o Based on the required minimum flow rate, the notch angle should probably range between 20 and 45
degrees. For example, at a 20 degree notch angle, the head would range between 0.67 feet to 0.78 feet
at 0.17 cfs and 0.25 cfs, respectively.
• Rectangular Contracted Weir — The rectangular weir would be designed the same as the sketch except the
opening would be a rectangle instead of a "V". The advantage of the rectangular weir is there will be greater
variation in head for a corresponding variation in flow rate. While the range of flow measured in a rectangular
weir is less, that does not matter in this situation since we are targeting a specific minimum value.
o For example, If the width of the rectangular weir opening was 0.2 feet, the height would range from
0.41 feet to 0.54 feet at 0.17 cfs and 0.25 cfs, respectively.
I will be in touch with more information.
Thank you,
Adam
Adam Tripp, PG
Senior Geologist
Headwater Environmental, Inc.
30 Westgate Parkway, #356, Asheville, NC 28806
Ph: 919-619-2084
From: Adam Tripp
Sent: Monday, January 23, 2023 4:46 PM
To: Moore, Andrew W <[e-mail]>
Cc: Tarver, Fred <[e-mail]>; Leslie, Andrea J <[e-mail]>; Stancil, Vann F
<[e-mail]>
Subject: RE: USGS response to DWR USGS Low Flows request # 2023-250 (dated 2022/12/03) for Bearwallow Branch
Madison County... RE: [EXTERNAL] Low -flow request approval

Good afternoon All,
I just wanted to send over some Site photos to guide our discussion tomorrow:
Stream with trout farm intake on the left and original channel on the right. Potential location for V-Notch Weir is in the
channel on the right.

� y
6 i ARM
\$
" t I
i ?
-� _� "`�� _ ,,. .ems '"'?� ^him -al �rY..'�.J 'Nz°��" ' ('a!►
xm"
a
41
--C (M` 'i+1� R . � ,v i31 ' •f Sri.. - :.�'�. �' �
r e
r�l
�^ 1
IA
. 1

View of the proposed V-Notch Weir location.
Looking forward to speaking with you.
Thanks,
Adam
Adam Tripp, PG
Senior Geologist
Headwater Environmental, Inc.
30 Westgate Parkway, #356, Asheville, NC 28806
Ph: 919-619-2084
From: Moore, Andrew W <[e-mail]>
Sent: Thursday, January 12, 2023 9:47 AM
To: Adam Tripp <[e-mail]>
Cc: Tarver, Fred <[e-mail]>; Leslie, Andrea J <[e-mail]>; Stancil, Vann F

<[e-mail]>
Subject: RE: USGS response to DWR USGS Low Flows request # 2023-250 (dated 2022/12/03) for Bearwallow Branch
Madison County... RE: [EXTERNAL] Low -flow request approval
Thursday works for me.
Andrew W Moore, P.G.
Environmental Specialist 11, Division of Water Resources
North Carolina Department of Environmental Quality
Office: [phone]
[e-mail]
D 5 i;:; A
�
,: �: � ��� E_
NORTH CAROLINA - C1110)
Department of Environmental Quality
Email correspondence to and from this address is subject to the North
Carolina Public Records Law and may be disclosed to third parties.
From: Adam Tripp <[e-mail]>
Sent: Thursday, January 12, 2023 9:37 AM
To: Moore, Andrew W <[e-mail]>
Cc: Tarver, Fred <[e-mail]>; Leslie, Andrea J <[e-mail]>; Stancil, Vann F
<[e-mail]>
Subject: RE: USGS response to DWR USGS Low Flows request # 2023-250 (dated 2022/12/03) for Bearwallow Branch
Madison County... RE: [EXTERNAL] Low -flow request approval
CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
Report Spam.
Andrew,
I am fairly flexible next week. Would sometime Wednesday or Thursday work for everyone?
Thank you,
Adam
Adam Tripp, PG
Senior Geologist
Headwater Environmental, Inc.
30 Westgate Parkway, #356, Asheville, NC 28806
Ph: 919-619-2084
From: Moore, Andrew W <[e-mail]>
Sent: Thursday, January 12, 2023 8:53 AM
To: Adam Tripp <[e-mail]>
Cc: Tarver, Fred <[e-mail]>; Leslie, Andrea J <[e-mail]>; Stancil, Vann F
<[e-mail]>

Subject: RE: USGS response to DWR USGS Low Flows request # 2023-250 (dated 2022/12/03) for Bearwallow Branch
Madison County... RE: [EXTERNAL] Low -flow request approval
Adam,
I'd like to keep this project moving forward. I'm available to meet next week and have copied others on this email that
may be involved in the discussion.
What's your availability next week?
Andrew W Moore, P.G.
Environmental Specialist 11, Division of Water Resources
North Carolina Department of Environmental Quality
Office: [phone]
[e-mail]
DE_
ki;
NORTH CAROLINA -
Department of Environmental Quality
Email correspondence to and from this address is subject to the North
Carolina Public Records Law and may be disclosed to third parties.
From: Adam Tripp <[e-mail]>
Sent: Monday, December 19, 2022 6:12 PM
To: Moore, Andrew W <[e-mail]>
Subject: FW: USGS response to DWR USGS Low Flows request # 2023-250 (dated 2022/12/03) for Bearwallow Branch
Madison County... RE: [EXTERNAL] Low -flow request approval
CAUTION: External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
Report Spam.
Andrew,
See low flow response below.
I would like to look into this data a bit more as there is quite a large range for the estimated annual 7Q10 low -flow
discharges. Perhaps we can find a time to discuss after the holidays.
Thank you,
Adam
Adam Tripp, PG
Senior Geologist
Headwater Environmental, Inc.
30 Westgate Parkway, #356, Asheville, NC 28806
Ph: 919-619-2084

From: Weaver, John C <[e-mail]>
Sent: Monday, December 19, 2022 5:55 PM
To: Adam Tripp<[e-mail]>
Cc: [e-mail]; Montebello, Michael J<[e-mail]>; Dowden, Doug
<[e-mail]>; Litzenberger, Kristin S <[e-mail]>; Denard, Derek
<[e-mail]>; Albertin, Klaus P <[e-mail]>; Weaver, John C <[e-mail]>
Subject: USGS response to DWR USGS Low Flows request # 2023-250 (dated 2022/12/03) for Bearwallow Branch
Madison County... RE: [EXTERNAL] Low -flow request approval
Mr. Tripp,
In response to your inquiry about the low -flow characteristics for Bearwallow Branch adjacent Howard Moore Road (NC
Secondary Road 1163) near Luck in southwestern Madison County, the following information is provided:
A check of the low -flow files here at the USGS South Atlantic Water Science Center (SAWSC, Raleigh office) does not
indicate a previous low -flow determination for the point of interest, identified by the lat/long coordinates (35.72166, -
82.85458) provided via email dated 12/03/2022 from the DWR USGS Low Flows portal following your request
submission.
No USGS discharge records are known to exist for the point of interest.
In the absence of site -specific discharge records sufficient for a low -flow analysis, estimates of low -flow characteristics at
ungaged locations are determined by assessing a range in the low -flow yields (expressed as flow per square
mile drainage area, or cfsm) at nearby sites where estimates have previously been determined.
A basin delineation completed using the online USGS StreamStats application for North Carolina
(https://streamstats.usgs.gov/ss/) indicates the drainage area for the point of interest (StreamStats adjusted
coordinates 35.72166,-82.85458 NAD83) is 1.24 sgmi, which confirms the drainage area submitted as part of the
request information.
For streams in Madison County, low -flow characteristics published by the USGS are provided in the following reports:
(1) The first is a statewide report completed in the early 1990's. It is USGS Water -Supply Paper 2403, "Low -flow
characteristics of streams in North Carolina" (Giese and Mason, 1993). An online version of the report is available
at http://pubs.usgs.gov/wsp/2403/report.pdf. The report provides the low -flow characteristics (based on data through
1988) via regional relations and at -site values for sites with drainage basins between 1 and 400 sgmi and not considered
or known to be affected by regulation and/or diversions.
(2) The second is a statewide report published in March 2015. It is USGS Scientific Investigations Report 2015-5001,
"Low -flow characteristics and flow -duration statistics for selected USGS continuous -record streamgaging stations in
North Carolina through 2012" (Weaver, 2015). The report is available online
at http://pubs.usgs.gov/sir/2015/5001/. The report provides updated low -flow characteristics and flow -duration
statistics for 266 active (as of 2012 water year) and discontinued streamgages across the state where a minimum of 10
climatic years discharge records were available for flow analyses.
Low -flow characteristics estimated for point of interest:
Streamflow records are somewhat limited for streams in western and southwestern Madison County. Inspection of the
above two reports indicates the presence of eleven (11) nearby selected USGS partial -record sites (10) and continuous -
record streamgages (1) across western Madison County, northwestern Buncombe County, and northeastern Haywood

County in the general vicinity of the point of interest where low -flow characteristics were published. Among these 11
index sites, the low -flow discharge yields for the indicated flow statistics are as follows:
Annual 7Q10 low -flow yields =_> from 0.065 to 0.22 cfsm (average about 0.14 cfsm, median about 0.15 cfsm)
Annual 30Q2 low -flow yields =_> from 0.18 to 0.39 cfsm (both average and median about 0.29 cfsm)
Winter 7Q10 low -flow yields =_> from 0.13 to 0.29 cfsm (both average and median about 0.2 cfsm)
Annual 7Q2 low -flow yields ==> from 0.15 to 0.33 cfsm (both average and median about 0.24 cfsm)
Average annual discharge yields ==> from 0.73 to 1.4 cfsm (both average and median about 1 cfsm)
Application of the above range in yields to the drainage area (1.24 sgmi) for the point of interest results in the following
estimated low -flow discharges:
Annual 7Q10 low -flow discharges =_> from 0.081 to 0.27 cfs (average about 0.17 cfs, median about 0.19 cfs)
Annual 30Q2 low -flow discharges =_> from 0.22 to 0.48 cfs (both average and median about 0.36 cfs)
Winter 7Q10 low -flow discharges =_> from 0.16 to 0.36 cfs (both average and median about 0.25 cfs)
Annual 7Q2 low -flow discharges ==> from 0.19 to 0.41 cfs (both average and median about 0.3 cfs)
Average annual discharge discharges ==> from 0.91 to 1.7 cfs (both average and median about 1.2 cfs)
Please note:
(1) The estimated flows are provided in units of cubic feet per second (cfs).
(2) The low -flow yields provided above are rounded to 2 significant figures. Estimated low -flow discharges less than 1
cfs are rounded to 2 significant figures. If between 1 and 100 cfs, then rounded to 1 decimal place; if greater than 100,
then rounded to the nearest whole number (zero decimal places).
(3) The information provided in this message is based on a preliminary assessment and considered provisional, subject
to revision Dendine collection of future data and further analvses.
These provisional streamflow statistics are provided via the DWR USGS Low Flows cooperative agreement between
the USGS and the N.C. Department of Environmental Quality, Division of Water Resources.
Hope this information is helpful.
Thank you.
Curtis Weaver
J. Curtis Weaver, Hydrologist, PE Email: icweaver(@usas.00v
USGS South Atlantic Water Science Center Online: httos://www.usas.cov/centers/sa-water
North Carolina - South Carolina - Georgia
3916 Sunset Ridge Road
Raleigh, NC 27607
Phone: [phone] // Fax. [phone]
From: Albertin, Klaus P <[e-mail]>
Sent: Saturday, December 3, 2022 7:48 AM
To: [e-mail]
Cc: Albertin, Klaus P <[e-mail]>; [e-mail]; Weaver, John C <[e-mail]>;

Montebello, Michael J <[e-mail]>; Dowden, Doug <[e-mail]>; Litzenberger,
Kristin S <[e-mail]>; Denard, Derek <[e-mail]>
Subject: [EXTERNAL] Low -flow request approval
This email has been received from outside of DOI - Use caution before clicking on links, opening attachments, or responding.
Your request has been approved and will be forwarded to USGS. A response from USGS usually takes 7 - 10 business
days.
Request Flow Statistic Approval
Request ID: 250
Requestor: Adam Tripp
Requestor e-mail: [e-mail]
Requestor Phone: [phone]
Local Government:
Public Water Supply:
Consultant:
Contact:
Reason: Permit
River/Stream: Bearwallow Branch
Drainage Area (sq. mi.): 1.24
Latitude: 35.72166
Longitude:-82.85458
Other Information: Location is the intake for a trout farm, located adjacent and to the east of a round house (yurt?) on
the property,
Statististics: ["7Q10"]
Approved by: Albertin, Klaus P
10