20051117 Ver 2_More Info Received_20081020

LiSSARA PARTNLRS. LLC
1210 Forest Wood Drive
Lewisville, NC 27023
NC Department of Environment and Natural Resources
Division of Water Quality
401 Oversight/Express Review Permits Unit r.v , r{ ; `; ?,r
1650 Mail Service Center
Raleigh, North Carolina 27699-1650
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Attention: Ms. Coleen H. Sullins
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Subject: Lissara Development, Forsyth County
DWQ #20051117, Ver.2; USACE Action ID. No. 200520968
Ut to Yadkin River (030702, 12-(86.7), WSIV, C)
401 Water Quality Certification No. 3742 with Additional Conditions
Attachment: Engineering Tectonics, P.A. letter dated October 7, 2008
Fred R. Tarver, III, NCDENR-DWQ - In-Stream Flow Unit, email
dated July 8, 2008
J. Curtis Weaver, USGS North Carolina Water Science Center,
email dated October 15, 2008
Dear Ms. Sullins:
Pursuant to the subject permit please accept this letter and attachment as our
submittal of additional information in satisfaction of additional conditions
contained in our permit.
Conditions 12 and 14.
Per the USGS map provided you in the required documents for the above permit,
Clemmons Quad; the unnamed tributary we are impounding beginning at
coordinates 36°06'03.42"N and 80°26'57.21 "W and running north to the
confluence of a second stream at 36°06'45.71 "N and 80°26'55.90"W, is
graphically shown as an intermittent stream. Upon completion of the dam, the
remaining stream length from the downstream toe of the dam structure to the
confluence will be approximately one-hundred thirty feet (130').
Per the attached email from Mr. Fred R. Tarver, III, Environmental Specialist, NC
Department of Environment and Natural Resources, Division of Water Resources
- In-Stream Flow Unit, dated July 8, 2008; the intermittent unnamed tributary we
will impound is expected to have a Mean Annual Flow at or below 3.0 cfs.
Per the attached email from Mr. J. Curtis Weaver, Hydrologist, PE, USGS North
Carolina Water Science Center, dated October 15, 2008; the 7Q10 yield range to
this drainage area results in 7Q10 flow estimates of between 0.02 and 0.03 cfs.
The information contained in the above two emails clearly shows an expected
Mean Annual Flow and 7Q10 Flow to be well below the thresholds requiring a
minimum flow downstream of the dam. According to Mr. Weavers' email; the NC
Department of Environment and Natural Resources - Division of Water Quality, in
assessment of low-flow characteristics, designates any flow estimates equal to or
greater than 0.05 cfs as being "positive flow" and any statistic less than 0.05 cfs
would typically be considered as being equivalent to zero flow.
Confirmed by visual inspection over the course of the last four years this stream
has become completely dry annually during each of the last four summer
seasons of 2005 through 2008. It has been observed dry for extended periods
longer than 7 days and has repeated this condition for four consecutive years.
Most recently, and as confirmed during a site visit on September 8 by a local
representative of the Division of Water Resources, the stream was dry from the
last week of July to that date.
Based on the above information and summary of the attached emails it is our
contention, and further addressed in Mr. Tarvers' email, that we are not legally
required to provide a minimum flow downstream of the dam. It is also noted that
utilizing the standards from within the NC Department of Environment and
Natural Resources - Division of Water Quality; the stream has a 7Q10 Flow
estimate equal to zero which would therefore not require maintaining a minimum
flow.
We therefore contend that we have provided sufficient documentation to indicate
we have met the requirements of Conditions 12 and 14.
Condition 10.
The attached letter from Engineering Tectonics certifies that we have confirmed
the presence of non-erosive bedrock at each of the stream crossing locations,
adequate to support the design-loads of the open-bottom culverts, that meets or
exceeds the requirements set forth in Condition 10.
Very truly yours,
ang Icox
Liss Partners, LLC
Cc: Mr. Brant Godfrey
Mr. Jim Armentrout
From: Fred Tarver [[e-mail]]
Sent: Tuesday, July 08, 2008 2:39 PM
To: Lang Wilcox
Subject: Re: Lissara Stream Flow
Attachments: fred_tarver.vcf
Lang,
According to the topographic map (Clemmons Quad), the general location of the
proposed dam is on an intermittent stream, which is the third stream on the south
side upstream from the Yadkin River confluence of the unnamed receiving
stream. The unnamed receiving stream is the third stream on the east side of the
Yadkin River, downstream from Mill Creek.
Mr. Weaver's correspondence does not provide an estimate of the mean annual
flow. The mean annual flow is important for determining the protocol for
assessing the flow requirement for a dam under the dam safety rules. Assuming
that Mr. Weaver's correspondence is for an accurate location of the proposed
dam, given the drainage areas estimated, there is a reasonable expectation that
the mean annual flow will beat or below 3.0 cfs. Based on Mr. Weaver's 7Q10
estimates and the dam safety rules (Section .0502), it appears that the applicant
is not legally required to provide a minimum flow downstream of the dam. As I
stated in our conversation, the existence of a permitted discharge downstream of
the proposed dam would require a flow downstream equal to the 7Q10.
The Division of Water Resources reserves the right to adjust this estimate if new
data becomes available during the permitting of this proposed dam.
Fred Tarver
From: John C Weaver [e-mail]]
Sent: Wednesday, October 15, 2008 5:12 PM
To: Lang Wilcox
Cc: John C Weaver
Subject: Low-flow characteristics (7Q10) for unnamed tributary to Yadkin River
in western Forsyth County ...RE: Lissara Residential Subdivision, Forsyth County,
NC
Mr. Wilcox,
Follow-up to our phone conversation on October 14, 2008, and in response to your inquiry about the 7Q10
discharge for a location on an unnamed tributary in western Forsyth County, the following information is
provided:
A check of the low-flow files here at the USGS North Carolina Water Science Center (NC WSC) does not
indicate any previous determination of low-flow characteristics for the location you identified on the map
image attached to your email dated October 1. The only nearby location for which low-flow discharges
have been previously estimated is about 2,800 feet south-southwest of your location (or in the next basin
located west of your tributary of interest). The 7Q 10 estimated for this site was zero flow (station id
0211545815, drainage area 0.13 sqmi).
No site-specific discharge records are available for your site of interest. In the absence of data, low-flow
estimates are determined by assessing the range of low-flow yields (expressed as flow per square mile
drainage area, or cfsm) at nearby USGS sites where the 7Q10 discharge has been estimated. Once a range
or average of low-flow yields are known, then the drainage area for a point of interest can be used to
determine a flow estimate.
The "most recent" low-flow information published for streams in this area is in 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 through
http://pubs.er.usgs.gov/usgspubs/wsp/wsp2403. 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.
If you access the report, please note the online report files are provided in the ".DJVU" format and require a
particular Lizardtech plug-in, also available through a link displayed on the page. Or you can click an
adjacent link that will allow you to view the report as a group of images without the need for a plug-in.
Several pieces of information to consider...
(1) In Table 1 of this report, there are several nearby sites (02115500, 02115530, 02115671) for which
7Q10 discharge estimates are provided. Expressing these estimates as 7Q10 low-flow yields (again, flow
per square mile of drainage area, or cfsm) provides some indication of the yield range that could potentially
be applicable to your location. The 7Q10 low-flow yield range is from about 0.08 to 0.10 cfsm.
(2) A "quick-n-dirty" delineation of the basin upstream of the proposed impoundment indicates a drainage
area of about 0.25 sqmi. Applying the above 7Q 10 yield range to this drainage area results in 7Q 10 flow
estimates of 0.02 to 0.03 cfs. As discussed during our phone conversation, we typically consider 7Q10
flow estimates less than 0.05 cfs to be equivalent to zero flow.
(3) In its assessment of low-flow characteristics, the N.C. Division of Water Quality (DWQ) designates any
flow estimates equal to or greater than 0.05 cfs as being "positive flow" for that particular statistic. Any
flow statistic less than 0.05 cfs would typically be considered as being equivalent to zero flow. Because of
the uncertainty associated with low-flow estimates, designating 0.05 cfs as positive flows gives the DWQ a
margin to work with in evaluating the feasibility of a NPDES point-source discharge permit.
Correspondingly, estimates provided by the USGS NC WSC that are less than 0.05 cfs are usually
considered equivalent to zero flow.
Hope this information is helpful.
Thank you.
Curtis Weaver
J. Curtis Weaver, Hydrologist, PE
USGS North Carolina Water Science Center
3916 Sunset Ridge Road
Raleigh, NC 27607
Telephone: [phone] // Fax: [phone]
E-mail address -- [e-mail]
Internet address -- http://nc.water.usgs.gov/
ENGINEERING TECTONICS, P.A.
ENGINEERS • GEOLOGISTS • HYDROLOGISTS
1720 Vargrave Street, Winston-Salem, NC 27107 [phone]
October 7, 2008
NC Department of Natural Environment and Natural Resources
Division of Water Quality
401 Oversight/Express Review Permits Unit
1650 Mail Service Center
Raleigh, North Carolina 27699-1650
Attention: Ms. Coleen H. Sullins
Subject: Lissara Development
(Forsyth) 401_IC
Stream Crossings
Dear Ms. Sullins:
Pursuant to DWQ Permit #20051117, Ver.2 and US Army Corps of Engineers Action ID
No. 200520968 for an unnamed tributary to the Yadkin River for the proposed Lissara
Development, this letter is written to respond to condition 10 of the permit. A similar
response was provided in a previous letter to you dated August 27, 2008. That letter
included a map showing the proposed locations of two bottomless culverts. These
locations have now been selected for the actual construction of the culverts.
As stated in my previous letter, we have conducted an investigation of the subsurface
conditions at the locations of the culverts to determine the condition of the bedrock. A
total of four (4) test pits were excavated at each of the locations of the bottomless culverts
shown on the map in order to provide direct inspection of the condition of the rock
material. The pits extended through approximately 2-3 feet of regolith soil material
before the top of bedrock was encountered. The rock in the test pits consists of
weathered mica schist which according to the NC State Geologic Map of 1985 by Brown,
et al, is considered to be of Cenozoic Age. The area lies within the Milton Belt, a zone of
metamorphosed rock which was originally deposited as sands and clays in a shallow
marine environment. The rock has undergone numerous periods of metamorphism to at
least a sillimanite facies during the Paleozoic.
The rock exposed in the test pits is a massive rock with a hardness of between 6 and 8 on
the Mohs hardness scale. The original bedding planes are still visible in the rock. The
bedding provide for a planar parting face that dips to the south at an angle of
approximately 25 degrees. The top of the rock surface is fairly regular within the test pits
and is absent of signs of faulting even though it is fractured throughout. While no soil
test borings were completed at the specific locations of the test pits, extensive drilling and
testing in this rock unit throughout the development indicates that the rock is quite dense
and hard. Standard Penetration Testing of the rock at other locations in the development,
I: .
performed in general accordance with ASTM Method D-1586, confirm that the rock has
a penetration resistance greater than 50 blows per 6 inches of penetration. Similar
conditions were observed with rock outcropping within the stream bed along the axis of
the proposed bottomless culverts.
It is our professional opinion, based on inspection of the rock in the test pits at the
locations cited herein, that a rock surface exists in the areas of the proposed shallow
footings and within the channel section of the bottomless culverts that is and will be non-
erosive at a design storm flow equal to a 25-year, 24-hour return interval.
We understand that the culverts and bridges will not be turned over to the State or any
municipal body for ownership or maintenance. We have been advised that the roadways
and bridges will be private.
We hope that this letter provides the necessary information needed at this time for the
project to proceed. If you have any questions or desire additional information, please do
not hesitate to contact me directly at 336 724 6994 ext. 104.
Y,
CS, P.A.
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Chief Engineering Geologists:
NC License No. 165

ENGINEERING TECTONICS, RA.