20190288 Ver 1_Staff Comments_20190904

Strickland, Bev
From: Brady, Harold M.
Sent: Wednesday, September 04, 2019 9:19 AM
To: Homewood, Sue
Subject: FW: USGS response to DWR for Buckeye Creek
Sue,
The USGS analysis of Buckeye Creek confirms the mean annual flow (MAF) estimate done by Jennings Environmental
(6.32 cfs) is within the expected range (5.4 to 6.8 cfs). The final values are in blue (below), with the MAF estimated range
in the bottom line. Based on our call from last week, I just wanted to confirm this calculated value with you.
Please let me know if anything comes up with this project.
Thank you,
Harold M. Brady
Water Supply Development Coordinator
Division of Water Resources— Water Planning Section
North Carolina Department of Environmental Quality
919 707-9005 office
[e-mail]
Archdale Building
1601 Mail Service Center
Raleigh, NC 27699
Email correspondence to and from this address is subject to the
North Carolina Public Records Law and may be disclosed to third parties.
From: Weaver, John [mailto:[e-mail]]
Sent: Tuesday, September 3, 2019 6:00 PM
To: Brady, Harold M. <[e-mail]>
Cc: Grzyb, Julie <[e-mail]>; DWR USGS Low Flows <[e-mail]>; Albertin, Klaus P
<[e-mail]>; Hill, David A <[e-mail]>; Kebede, Adugna <[e-mail]>;
Fine, Jason M <[e-mail]>; Fransen, Tom <[e-mail]>; Weaver, John C <[e-mail]>
Subject: USGS response to DWR USGS Low Flows request # 2019-22 (dated 2019/08/29) for Buckeye Creek XXXX
County... Re: [EXTERNAL] Low -Flow Request - Approved & Sent to USGS
External email. Do not click links or open attachments unless you verify. Send all suspicious email as an attachment to
[e-mail]
Harold,

In response to your inquiry about the low -flow characteristics (7Q 10, 30Q2, W7Q 10, 7Q2, average annual
discharge) for USGS Sta. 0347927160 Buckeye Creek near Cannon Gap (drainage area 2.84 sqmi, adjacent to
Grassy Gap Creek Road, at the border between Watauga and Avery Counties, also in vicinity of Beech
Mountain), the following information is provided:
Low -flow estimates were initially determined for this ungaged point of interest in July 2011 in response to a separate request submitted by a
consultant on behalf of the Town of Beech Mountain. Low -flow estimates provided via email dated July 29, 2011, were determined based on
transfer of flow characteristics (via pro -rated drainage area) using previously published low -flow statistics for nearby index sites in the
vicinity of the point of interest.
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
(hftp://water.usgs.gov/osw/streamstats/north carolina.html) indicates the drainage area for the point of interest (36.21574, -
81.90842 NAD83) is 2.85 sqmi. This is practically identical to the drainage area of 2.84 sqmi used in the low -flow estimates in
response to the 2011 request; therefore, the drainage area of 2.84 sqmi is maintained for the purposes of the low -flow
determinations.
For streams in Watauga and Average Counties, low -flow characteristics published by the USGS are provided in
two 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
sqmi 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.
Inspection of the two reports indicates the presence of seven (7) nearby selected USGS partial -record sites (4)
and continuous -record streamgages (3) in general vicinity of the point of interest where low -flow characteristics
were published. Among these 7 sites, the low -flow discharge yields for the indicated flow statistics are as
follows:
Annual 7Q10 low -flow yields ==> from 0.21 to 0.33 cfsm (average 0.27 cfsm, median 0.28 cfsm)
Annual 30Q2 low -flow yields ==> from 0.47 to 0.73 cfsm (average about 0.6 cfsm, median 0.62 cfsm)
Winter 7Q10 low -flow yields ==> from 0.31 to 0.48 cfsm (average 0.38 cfsm, median 0.39 cfsm)
Annual 7Q2 low -flow yields ==> from 0.37 to 0.56 cfsm (average 0.47 cfsm, median 0.46 cfsm)
Average annual discharge yields ==> from 1.9 to 2.4 cfsm (average about 2.1 cfsm, median about 2 cfsm)
Application of the above range in yields to the drainage area (2.84 sqmi) for the point of interest results in the
following estimated low -flow discharges:

Annual 7Q10 discharges ==> from about 0.6 to 0.94 cfs (average 0.77 cfs, median about 0.8 cfs)
Annual 30Q2 discharges ==> from about 1.3 to about 2.1 cfs (average about 1.7 cfs, median about 1.8 cfs)
Winter 7Q10 discharges ==> from 0.88 to about 1.4 cfs (both average and median about 1.1 cfs)
Annual 7Q2 discharges ==> from about 1.1 to about 1.6 cfs (both average and median about 1.3 cfs)
Average annual discharge ==> from about 5.4 to about 6.8 cfs (average about 6 cfs, median about 5.7 cfs)
Please note:
(1) The estimated flows are provided in units of cubic feet per second (cfs).
(2) The estimated low -flow characteristics provided above are very comparable to the estimates provided in response to the 2011 request and
are considered the most current set of estimates given the recent publication of the second above -referenced report.
(3) The information provided in this message is based on a preliminary assessment and considered provisional, subject to revision pending
collection of future data and further analyses.
These provisional streamflow statistics are provided via the DWR USGS Low Flows cooperative agreement between 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: [e-mail]
USGS South Atlantic Water Science Center Online: httvs://www.usas.aov/centers/sa-water
North Carolina - South Carolina - Georgia
3916 Sunset Ridge Road
Raleigh, NC 27607
Phone: [phone] // Fax. [phone]
On Thu, Aug 29, 2019 at 10:16 AM Fransen, Tom <tom.fransen(c/�,ncdenr.gov> wrote:
Your request has been approved and sent to USGS.
Request for USGS to provide low -flow statistics.
Request details:
Request ID: 22
Date of request: 8/29/2019 11:50:28 AM
Requestor: Harold Brady
Phone Number: 9197079005
Program: Water Planning Section
Email: (anonymous)
Agency: Division of Water Resources (DWR) or other Department of Environmental Quality (DEQ) Division
Have you spoken with someone from DWR?:
Reason for request: Water Supply Water Availability/Safe Yield
Whom did you speak with?:
Local Government:
Consultanting Company/Organization:
Contact Name:

Contact Phone Number:
Contact Email:
Reason for request: Water Supply Water Availability/Safe Yield
Permit Number:
Public Water Supply ID: 01-95-104
Site Information:
River/Stream: Buckeye Creek
Latitude - Longitude: 36.2159 Other location Information:
Statistics being requested: ["7Q10","7Q10 - Winter","30Q2","7Q2","Average Annual"]
Other information: Last evaluated in 2011 by JC Weaver
Approved by: Grzyb, Julie ([e-mail])
Comments: