HomeMy WebLinkAbout20051117 Ver 2_More Info Received_20090219LISSARA PARTNERS. LLC
1210 Forest Wood Drive
Lewisville, NC 27023
February 10, 2009
FEB 19 2009
DENR - WATER QUALITY
WETLANDS AND STORM WATER 8RANCf1
North Carolina Department of Environment and Natural Resources
Division of Water Quality
1650 Mail Service Center
Raleigh, NC 27699-1650
Cyndi Karoly, Supervisor
401 Oversight/Express Review Permitting Unit
Subject: Lissara Development
Ut to Yadkin River [030702, 12-(86.7), WSIV, C]
401 Water Quality Certification No. 3742 with Additional Conditions
Reference: DWQ Project #05-1117, Ver.2, Forsyth County
Dear Ms. Karoly,
Based on our previous conversations and correspondence, it is your position that
the North Carolina Division of Water Quality (DWQ) will require Lissara Partners,
LLC. to provide a continuous minimum 7Q10 release flow of 0.02 cfs from our
Llssara Lake as referenced in the above-mentioned 401 Water Quality
Certification. DWQ will require this release rate regardless of minimal inflow, if
any, from any tributaries which may feed the lake.
As we have previously presented to your department, Chapter 15, Subchapter K,
Section .0502(b)(1) of the North Carolina Administrative Code, pertaining to
7Q10 requirements, reads as follows:
" If the mean annual daily flow is less than or equal to 3 0 cfs and the 7-
day, 10-year low flow (7Q10) is less than or equal to 0.2 cfs and if there
are no existing point source discharges of wastewater to the affected
stream reach; then no minimum release shall be required"
You will recall from earlier correspondence that the flow characteristics of the
stream we will be impounding are significantly under the thresholds as outlined
above and thus under the requirements for a minimum release. I continue to be
troubled by DWQ's inability to properly recognize and understand the applicability
of this section of the administrative code to the Lissara Lake project.
Under most circumstances, I would work my way up the bureaucratic ladder
seeking a different result to what I consider to be a rather obvious circumstance.
However, as an economic realist, I must admit a need to move on with the more
important aspects of this project. Thus I have, in consultation with my project
principals, made a purely business decision. As a means of ending the project
delays associated with this issue, I am providing you with the pertinent design
concepts and details for the installation of a lake siphon which will adequately
provide a 7Q10 flow rate of 0.02 cfs from our Lissara Lake to the eighty feet (80')
of stream bed that exists from the foot of the dam to the next downstream
tributary.
As you know, we have previously discussed and agreed that the cost effective
means of providing the required flow achieved by a siphoning system would also
be deemed a satisfactory approach by DWQ. I trust that this is still the case and
that the enclosed information will put this matter to rest.
Upon further engineering investigation into this approach we have been advised
that, because of the flow-loss due to friction, we will actually need a two-inch
PVC pipe to accomplish the 0.02cfs flow. We are also advised that the intake
elevation could be as shallow as three-feet below full-pond elevation of 800 MSL.
However, due to our desire to have the intake located away from surface debris,
potential tampering or accidental damage, we prefer to locate the intake ten-feet
below full-pond.
A description of the proposed installation is as follows:
PROVISION FOR DOWNSTREAM WATER DELIVERY PIPE
AT LISSARA DAM TO SATISFY 7Q10 EXPECTATIONS
In furtherance of the North Carolina Division of Water Quality directive requiring a
7Q10 water release from the proposed Lissara Lake of 0.02 cubic feet per
second, it is proposed that a traditional siphon system be installed within the lake
to facilitate the required water release. The system shall be constructed utilizing
2-inch diameter schedule 40 PVC piping and will incorporate an upstream check
valve, downstream ball valve and priming orifice. The installation will be field
calibrated to provide a minimum flow of 0.02 cubic feet per second. As a means
of protecting the intake orifice from clogging, slotted PVC pipe encased within
well screening cloth will be utilized.
In order to ensure that the siphon intake will not be damaged by surface debris,
potential tampering or accidental causes, the intake orifice will be located ten feet
below the lake full pond elevation of 800 ft. mean sea level. The siphon outlet will
be located such that its discharge will empty into a small rip rap energy dissipator
at the downstream toe of the dam into the existing stream.
Please advise as to your acceptance of the above information in satisfying
Conditions 12 and 14 of our permit.
Very truly yours,
?ang Liss LLC
Cc: Jim Armentrout - Esquire
Brant Godfrey - Esquire
Pete Ramey
Beau Dancy
Steve Tedder - NCDENR-DWQMSRO
Chuck Wakild, Deputy Director/NCDENR-DWQ/Raleigh
Matt Matthews - NCDENR-DWQ/Raleigh