NC0045993_Correspondence_20220610

Baker, Caroline D
From: Weaver, John C <[e-mail]>
Sent: Friday, June 10, 2022 1:53 PM
To: Xiao, Min
Cc: Kebede, Adugna; Montebello, Michael J; Dowden, Doug; DWR USGS Low Flows;
Denard, Derek; Albertin, Klaus P; Weaver, John C
Subject: USGS response to DWR USGS Low Flows request # 2022-200 (dated 2022/06/03) for
Richardson Creek Union County ... RE: [EXTERNAL] Low -flow request approval
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Min,
In response to your inquiry about the low -flow characteristics for a location on Richardson Creek adjacent Ashcraft
Avenue near Monroe in central Union County, the following information is provided:
A check of the low -flow files here at the USGS South Atlantic Water Science Center (Raleigh office) indicates
previous low -flow determinations for locations on Richardson Creek and its tributaries near the point of
interest, identified by the lat/long coordinates (34.9848,-80.5101) provided via email dated 06/03/2021 from
the DWR USGS Low Flows portal following your request submission. However, the point of interest also is
located about 1,700 feet upstream from a USGS partial -record site on Richardson Creek at SR 1751 near
Monroe (station id 02125223, NWIS drainage area = 54.6 sqmi, StreamStats-delineated drainage area = 54.9 sqmi, at
NC Secondary Road 1751... Walkup Avenue) with records of 13 miscellaneous measurements obtained during the 1970-
73, 1975 water years.
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 index 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 34.98480,-80.51003 NAD83) is 54.5 sqmi, slightly less than the drainage area submitted as part of the
request information.
For streams in Union 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 sqmi and not considered
or known to be affected by regulation and/or diversions.
(2) The second is a basin -wide report for the Rocky River basin published in 2003. It is USGS Water -Resources
Investigations Report 03-4147, "Low -Flow Characteristics and Profiles for the Rocky River in the Yadkin -Pee Dee River

Basin, North Carolina, through 2002" (Weaver and Fine, 2003). An online version of the report is available through
http://Pubs.usgs.gov/wri/wri034147/. The report provides the low -flow characteristics (based on data through 2002)
for continuous -record gaging stations and partial -record sites within the Rocky River basin. The report also provides
low -flow discharge profiles (7Q10, 30Q2, winter 7Q10, and 7Q2) for the Rocky River from its headwaters in Mecklenburg
County to its mouth.
(3) The third 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:
Inspection of the Rocky River basin -wide low -flow report (item #2 referenced above) indicates the presence of
numerous USGS partial -record sites and continuous -record streamgages across the part of Union County within the
Rocky River basin in general vicinity of the point of interest where low -flow characteristics were published. This group of
index sites includes the downstream partial -record site on Richardson Creek at SR 1751 near Monroe. Because the point
of interest is located about 1,700 feet upstream from the partial -record site with almost negligible differences in
drainage areas between the two stream locations , it was judged reasonable and appropriate to use the low -flow
characteristics for the site as being applicable to the point of interest without pro -rating for drainage area.
USGS Sta. 02125223 Richardson Creek at SR 1751 near Monroe (at NC Secondary Road 1751... Walkup Avenue)
NWIS drainage area = 54.6 sgmi, StreamStats-delineated drainage area = 54.9 sqmi
In table 6 on page 22 of the Rocky River basin -wide low -flow report, the following low -flow statistics are provided:
Period of analysis: 1970-73, 1975 water years
Annual 7Q10 discharge = 0.3 cfs
Annual 30Q2 discharge = 0.7 cfs
Annual winter 7Q10 (W7Q10) discharge = 0.5 cfs
Annual 7Q2 discharge = 0.5 cfs
Annual average discharge = estimated approximately 49 cfs (based on average annual unit flow of 0.9 cfs from table 6 on
page 22 applied to NWIS drainage area of 54.6 sgmi)
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 oendine 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. icweaverOusas.aov
USGS South Atlantic Water Science Center Online. httvs://www.uses.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: Friday, June 3, 2022 10:46 AM
To: Xiao, Min <[e-mail]>
Cc: Albertin, Klaus P <[e-mail]>; [e-mail]; Weaver, John C <[e-mail]>;
Montebello, Michael J<[e-mail]>; Dowden, Doug <[e-mail]>; DWR USGS
Low Flows <[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: 200
Requestor: Min Xiao
Requestor e-mail: min.xiaoC5bncdenr.gov
Requestor Phone: [phone]
Local Government:
Public Water Supply:
Consultant:
Contact:

Reason: Permit
River/Stream: Richardson Creek
Drainage Area (sq. mi.): 54.6
Latitude: 34.9848
Longitude:-80.5101
Other Information: Stream Segment: 13-17-36-(5) Basin/HUC: 03-07-14/030401050504 USGS Topo
Quad: H16NE
Statististics: ["7Q10","7Q10 - Winter","30Q2","7Q2","Average Annual"]
Approved by: Albertin, Klaus P