20041796 Ver 1_Complete File_20041214

Qk W ATF9~ Michael F. Easley, Governor
~O G William G. Ross Jr., Secretary
North Carolina Department of Environment and Natural Resources
a Alan W. Klimek, P.E. Director
Division of Water Quality

July 13, 2006
DWQ EXP No. 04-1796
Wake County
CERTIFIED MAIL: RETURN RECEIPT REQUESTED

Villages of Swift Creek, LLC
C/o Mr. Johnathan Skinner
729 Thimble Shoals Boulevard, Suite 6C
Newport News, VA 23606
Subject Property: Mirror Lake Subdivision
EXPRESS REVIEW PROGRAM NOTIFICATION

Dear Mr. Skinner:

On January 23, 2006, the Division of Water Quality (DWQ) issued your Water Quality Certification to construct the
proposed subdivision. Within the Water Quality Certification that you received there is a condition that reads:
Notification of Construction

The applicant and/or authorized agent shall contact the DWQ Express Review Program in writing at the
letterhead address within 10 days of the commencement of construction.
This is a part of the Express Review Program that is required to ensure compliance during construction and post
construction. Therefore, if you have begun construction of these phases of your subdivision, you are required to
notify this office in writing by July 23, 2006. If you do not notify this office in writing and construction has started,
you are in violation of the Water Quality Certification Rules as required by 15A NCAC 2H.0507(c).
This letter is to notify you and make you aware of this new condition that has been written into the Water Quality
Certifications issued within the Express Review Program. Please call Lia Myott at [phone] if you have any
questions regarding this matter.

S' e ly,

Cyndi Karoly,
401 Oversight/Express Review Permitting Unit
CBK/lem
cc: Todd Preuninger, S&EC Inc., 11010 Raven Ridge Road, Raleigh NC 27614
USACOE, Raleigh Office
DWQ Raleigh Regional Office
File Copy
Central Files
Filename: 041796MirrorLakeSD(Wake)EXP+NOT

N°pthCaro};na
401 Oversight /Express Review Permitting Unit t <ltllCR~[1, J
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone: [phone] / FAX [phone] / Internet: http://h2o.enr.state.nc.us/ncwetlands
An Equal Opportunity/Affirmative Action Employer - 50% Recycled/ 10% Post Consumer Paper

WITHERS RAVEN EL
ENGINEERS I PLANNERS I SURVEYORS

August 9, 2005

Ms. Cynthia Van Der Wiele
NC-DWQ - 401 Express Program
2321 Crabtree Blvd., Suite 250
Raleigh, NC 27604

Re: Mirror Lake Subdivision - Plan Revisions
DWQ #:04-1796

Dear Ms. Van Der Wiele,

On December 14, 2004 we received a 401 Water Quality and Riparian Buffer Approval
for impacts associated with Mirror Lake subdivision and the Gorman Street road
widening. The original site plan proposed using a box culvert in order to cross the stream
channel. However, the NCDOT has requested that the box culvert be replaced with twin
54" culverts. The proposed impacts have not changed from those of our original
application. We have included the revised site plan so that you can update your files, as
per a conversation with Ms. Debbie Edwards, of your office. Please call if you have
questions or require additional information.

Sincerely, v D

AUG 9 2005
DENR - WATER (QUALITY
Todd Preuninger WETLANDS AND STORMWATER BRANCH

Withers & Ravenel

Cc: Ms. Jean Manuele - USACE

iii MacKenan Drive i Cary, North Carolina 27511 1 tel: [phone] fax: [phone]oo8 I www.withersravenet.com
107 Stokley Drive i Suite 104 1 Wilmington, North Carolina 28403 1 tel: [phone] fax: [phone]

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Mic:hual F. L'-;aslcy, (3OVCtnt)r
~aF AT~~Q Willism G. Ross 3r., $OVrttpcy
North Carolina r)_paVk_1L_I or ~,nvfixj=ent =kd Nuturrl ltgBOurOd~

i -I Alan W. Khrrok, A.E. DiNator
Q ~ 'Divisia~ of'Wsujr Qualify
December 14, 2004
DWQ EXIT No. 04-1796
Wake County
Page 1 of4
Villages of Swim Creel, LLC
Atlas; Sonathon Skimmer
729 Thimble Shoalls Blvd., Suite O'C
Newport: News, VA 23606
Subjcot'Propurty: Mirror ].,ake Subdivblan
UT to L. ke Johnson [03-04-02, 27-43-5-(1.$), WS-M, NSW3
APPROVAL of 401 Water Qs~ules ~A l~1CAC Z13 .0233) HvNi AD''DIADDITIONAL CrnO"Y'CIONShe
Neese River Buffer Protection
EXPRESS "VV'W PROGRAM

Dear Mr. Sldnaer: ow,
place You have our approval, in accor'ianG& with ~ ~d~l 51 linear conditions
feet of sa earsa.s and bel709 sq tiare feet (ft~)
~xrithin or otherwise impact 0.31 acres
of protected riparian buffers for the purpose of subdivision at the subject property, as described with2004
your application dated Noveinbar 11, 2004 and received by the Division of Water on November 15>
and all additional informatibn rc; have decided that the lmpac~s arc~, 200 and b~ h N c r 29,
2404. After reviewing your apIlcationwe
Division of Water Quality (DWQ) General Water Quality Certification Numiber(s) 3402 (Co 3f • The when Czgi eery (US allows is letters h lal olact as you rapP ed Autho zation Cert fic to forp, oimpac'ts to
proles (USAGE).
protected riparian buffers PIS 15p,NCAC 28 .0233. In addition, you should obtain or otherwise
comply with any other required federa~a staLe or local permit before yoti go Sediment ControlSNoh diseha ge,aaned~ Water ~ouppplryoject
including (but z1ot limited w) Erosion d impacts or to conduct impacts
Watershed regulations. Also, tJais approval to proceed with your proposed
to waters as depicted in your al)plicstion shall expire upon expiration of the 404 or CAMA Ptormit.
your
This approval is for the purpoSe attd design that you described in your application. If you change sold,
project, you must notify us anld'you may be required to send us a new application. If the property lotter
ere the new owner must be 9iv0a :a copy of This Certifioa cm andaapproval the hfiure) and the d one s ono ble for
complying v, ith all conditions If total fills for this project ( acf tion wetland or 150 linear feet of stun, compensatory ~ ~ow the coedtions l stedai ciethe s_atta in 1,A
NCAC 2I4 .0506 (h). This approval reqmres you
certification and any additiamd conditions listed below.
Conditions:
1. Impacts Pspproved
The following impacts are hereby approved as long as all of the other specific and acts are
conditions of this C e,rtifrcation (or Isolated Werland Permit) are 'met. No other imp ,o
approved including i:n6derntal impacts, t!lru~lla

401 wetland& oonlflcallon Vnu
I law Mail Serolce Canter, Raleigh, N h Carolinft h, NoRn 763 02ur5 On
2321 Crabtree goulovard, Suite 250, a g
phone- 919-733-178r3/FAX[phone]IIntemeir, PWh2o nr ,fit nc. 4lnctiu
Art Equal OpgDr uriity/Aalvrnative Action Employer - st,% Recycjed/10% Past Consumer P2per
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Ill lnnno W-J V V a

Villages of Swift Creek, LLC
page 2 of 4
12/14104

Amount Approved Plan. Locehon or Reference
(Utrits)
Stream 115 feet F'il,rurc #1&2
404 Wetlands 0.31 (acres) Fi ure ##1
Suffers 13,709 (s uarc -ft.) Figure 00-
2. Erosion & Sediment Control Practices

Erosion and sediment control -practices must be in full compliance with all specifications governing
the proper design, installation and operation and mainttenattce of such Best Managemcnt Practices in
order to protect surface 'w-;ters standards:
a, The erosion and s:dimcynt control measures for the project roust be designed, installed,
operated, and maintained in aocordance with the most recent version of the North Carolina
Sediment and ,Erosion Control Planning and.Design Manual.
b. The design, instal lation, operation, and maintemance: of the sediment and erosion control
measures must bt such that thty equal. or exceed, the requirements specified in the most
recent version of the North Carolina Sediment and Erosion Control Manual. The devices
shall be rnaintaimd on all construction sites, borrow shoes, and waste pile (spoil) projects,
including contra[ for-owned or leased borrow pits associated with the project.
3. No Waste, Spoil, Solids, or Fill of Any Kind
No waste, spoil, solids, o} fill of any kind shall occur in wetlands, waters, or riparian, areas beyond the
footprint of the impacts depicted in the Precoustruction Notice Application. All construction
activities, including the du:sigo, installation, operation, and maixltenanee of sediment and erosion
control Best Managemesn: Practices, shall be performed so that no violations of state water guali'ty
standards, statutes, or rubs occur.
4. No Sediment & Erosion control Measures w1n Wetlands or Waters
Sediment and erosion ca-'Itrol rneasares shall not be placed in wetlands or waters to the maximum
extent practicable. If placement of sediment and erosion control devices in wetlands and waters is
unavoidable, they shall bbv removed and the natural grade restored within six months of tho date that
the Division of Land Rwources has released the project.

5. Written Stormwater mlmagement Plan
Tl;e filial, writtan stormp vater management plans (including a signed and notarized. Operation and
Maintenance Agreemeeat.) dated October 9, 2004, must be implemented and the storsnwxre:r
management facilities shall be constructed and operational before any pemianent building is occupied
at the subject site. The structural stonnwater practices as approved by this Office as well as drainage
patterns must be mainta ned in perpetuity. No changes to the structural stormwater practices shall be
made without written authorization frond the Division of Water Quality.
in an effort to comply vith the diffuse flow provision of the Buffer Rule (15A NCAC 02B .0233(5)),
you have provided the 14WQ with level spreader designs dated November 11, 2004 and Noveinbcr
29, 2004_ The DWQ bt+lieves that if implemented, as par thews plans, diffuse flow will be achieved.
However, if diffuse flow as per 1SA NCAC 0213 .0233(5) is not achieved, then the DWQ shall be
notified and corrective :Lotion to restore diffuse flow shall be taken if necessary to impede the
formation of erosion g0lies. At Tw time shall storm,water from the proposed development be piped
directly through the bu:°fer without prior DWQ written authorization.

- • a L976V796 : 01 268925LL616 WNU-IJ M-nma : Wl7w ev : oT vooa- t T

WIUV4

villages of swift creek, LLC
Page 3 of 4
12114/04

The C)Peration & Maillterr,a,nce (O&M) agreeraent signed by the eurrent landowner must be approved
by the DWQ. This O&M agreement must transfer with the sale of the land or transfer of
responsibility for the stom.-ilwater facilities and the DWQ must be notified of every transfer.
6. Culvert Installation

Culverts required for this ;.:)rojeet shall be installed in such a manner that the original stream profiles are
not altered. Existing strewn dimensions (including the cross section dimensions, pattern, and
longitudinal profile) must be maintained above and below locations of each culvert. Culverts shall be
designed and installed to allow for aquatic life movement as well as to prevent head cutting of tlw
streams. If any of the exi;: ring pipes are or become perched, the aappropziaw stream grade shall be ro-
established or, if the pipet installed in a perched manner, the pipes shall be removed and re-installed
correctly,
7, Protective Fencing
The outside buffer, w'etl&nd or water boundary and along the construction corridor within these
boundaries approved -ua&~r -this authorization shall be clearly marked with orange warning fencing (or
similar high visibility ma serial) for the areas that have been approved to infringe within t'he'buffer,
wetland or water prior to any land disturbing activitYts to unsure compliance with 13.4 NCAC 2l3
.0233 and GC 3402.
8. Construction Stormwater Permit NCG- 010000

Upon the approval of an Erosion and Sedimentation Control Flan issued by the Division off Land
Resources (MR) or a D. A delegated local erosion and sedirr, ntation control program,
General st'ormwater pera-At (NCG010000) administered by DWQ is automatically issued to the
project. This General Permit allows sTormwater to be discharged during land disturbing construction
activities as stipulated by conditions in the permit. If yoiur project is covered by this permit
(applicable to consUVCti~€?zrprojects that disturb oat (1) or more acres], full compliance with permit
conditions including the sed aientation control plan, self-monitoitng, record keeping and reporting;
require'rrienta are required. .A copy of this permit and monitoring report forms may be found at
fct :1/ls~r,_G-nr,st ate.rtc.ar::~cu/Fi~rrr~.. Dt~c m:ere~.hirta.
9. Deed. Notifications
Deed notifications or similar nze6arnsms shall be placed on all relained jurisdictional wetlands,
waters and protective b-~ ffers in order to assure compliance for future wetland, water and buffer
impact. These mec'hani+sms shall be put in place prior to impacting any 'wetlands, waters and/or
buffers appro'v'ed for hxpaet render this Certification Approval and Authorization Certificate. A
sample deed notification. can be downloaded from the 401/Wetlands Unit web site at
http;//h2o_etir.st&W.nc.u:;/nowatlands. the text of the sample deed notification xnay be modificel as
appropriate to suit to this project.
10. Notification of Constru;%tion

'lhe applicant indict authorized agent shall contact the DWQ Express Review Program in writing at
the letterhead address within. 10 days of the commencement of construction.
11. Certificate of Cornpleti:gin

Upon completion of all work approved within, the 401 Water Quality Certification or applicable
Suffer Rules, snd any subsequent modifications, the applicant is required to return the attached

L90G9bB5 "01 Me=16T6 SONO'113M-OMs -WOJ 60 : C T t,00a-bT

rriinnxa Lf/j uua

Villages of Swift Creek, LLC
Page 4 of 4
12/14/Q4

certificate of completion to the 401AWedands Unit, North Carolina, Division of Water Quality, 1650
Mail Service Center, Raleigh, NC, 27699-1650.
Violations of any condition herein set forth may result in revocation of this Certification and may res'ul't in
criminal andlor civil penalties, The authorization to proceed with your proposed impacts or to conduct
impacts to waters as depicted ; n your applicatim and as autho'rim-d by this CCCti'fication, shall expire upon
expiration of the 404 or CA AL permit.

If you do not accept any of thc conditions of this Cerrification (associated with be approved wetland or
stream impacts), you may ask for an adjudicatosy hearing, You must act within 60 days of the date: that
you receive this letter. To ask for a hearing, send a written petition, which conforms to Chapter 15013 of
the North Carolina General Statutes to the Office of Adrainistrati'vo Re:arings, 6714 Mail Service Center,
Raleigh, N.C. 27699-6714. This certification and its conditions are final and 'binding unless you ask for a
hearing.
T1us lcurr uomplCiCS the rrvie:w of the Division of Water Quality under SeCtivri 401 of the C k*m Water
Act and the Neuse riparian buf'f'er protection rule as described within 15A. NCAC 2D .0233. If you halves
any questions, please telephmao C:`yndi Karoly at 919-733-9721 or Dtiborah Edwards at 919-733-9502.
Sincerely,

GZl

Alan W. Klimtk, P.E.

AWK/dae
Attachments: Certificate of Completion
GC 3402

Cc: Todd Preunit%ger-S&•EC
USA.CE Raleigh Reg„ulatory Field Office
DWQ Raleigh Regional Office
DLR Raleigh Regimml O1fioe
File Copy
Central piles
lralena=: 041796MirrorLakc:(Wake)EXP4. 01+ba,ffcr

I

<z :A L9b6~~86 I:ll 268922251:6 50Nti-1J.73M-0Ma:WO:U 6b=0T i700P--bti-D

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N"e
DEVELOPMENT CORPORATION 729 Thimble Shoals Blvd. • Suite 4-A
Newport News, Virginia 23606
LAND DEVELOPMENT [phone]
REAL ESTATE INVESTMENTS Fax [phone]
[e-mail]

April 5, 2005

Ms. Cyndi Karoly
401 Wetlands Certification Unit
North Carolina Division of Water Quality
1650 Mail Service Center
Raleigh, NC 27699-1650

RE: Mirror Lake Subdivision
UT to Lake Johnson (03-04-02, 27-43-5-(1.5), WS-111, NSW)

Dear Ms. Karoly:

This letter serves as notification that we have commenced construction at the
Mirror Lake subdivision. Please contact me directly if you have any questions.

Yours truly,

Jonathan Skinner
Development Manager U12@[q0W[R1
Villages of Swift Creek, LLC

cc: Alan Klimek APR 1 2005
DENR - WATER QUALITY
WETLAtibiMo STORMWVATER 8WO

p~pF W A
7- Michael F. Easley, Governor
William G. Ross Jr., Secretary
t/) North Carolina Department of Environment and Natural Resources
p Alan W. Klimek, P.E. Director
Division of Water Quality
December 14, 2004
DWQ EXP No. 04-1796
Wake County
Page 1 of 4
Villages of Swift Creek, LLC
Attn: Jonathon Skinner
729 Thimble Shoals Blvd., Suite 6C
Newport News, VA 23606
Subject Property: Mirror Lake Subdivision
UT to Lake Johnson [03-04-02,27-43-5-(1.5), WS-III, NSW]
APPROVAL of 401 Water Quality Certification and AUTHORIZATION CERTIFICATE per the
Neuse River Buffer Protection Rules (15A NCAC 2B.0233) with ADDITIONAL CONDITIONS
EXPRESS REVIEW PROGRAM

Dear Mr. Skinner:

You have our approval, in accordance with the attached conditions and those listed below, to place fill
within or otherwise impact 0.31 acres of wetlands, 115 linear feet of streams and 13,709 square feet (ft2)
of protected riparian buffers for the purpose of subdivision at the subject property, as described within
your application dated November 11, 2004 and received by the Division of Water on November 15, 2004
and all additional information received on November 22, 2004, November 24, 2004 and November 29,
2004. After reviewing your application, we have decided that the impacts are covered by the N.C.
Division of Water Quality (DWQ) General Water Quality Certification Number(s) 3402 (GC3402). The
Certification(s) allows you to use Nationwide Permit(s) 39 when issued by the US Army Corps of
Engineers (USACE). This letter shall also act as your approved Authorization Certificate for impacts to
the protected riparian buffers per 15A NCAC 2B .0233. In addition, you should obtain or otherwise
comply with any other required federal, state or local permits before you go ahead with your project
including (but not limited to) Erosion and Sediment Control, Non-discharge, and Water Supply,
Watershed regulations. Also, this approval to proceed with your proposed impacts or to conduct impacts
to waters as depicted in your application shall expire upon expiration of the 404 or CAMA Permit.
This approval is for the purpose and design that you described in your application. If you change your
project, you must notify us and you may be required to send us a new application. If the property is sold,
the new owner must be given a copy of this Certification and approval letter and is thereby responsible for
complying with all conditions. If total fills for this project (now or in the future) exceed one acre of
wetland or 150 linear feet of stream, compensatory mitigation may be required as described in 15A
NCAC 2H .0506 (h). This approval requires you to follow the conditions listed in the attached
certification and any additional conditions listed below.
Conditions:
1. Impacts Approved

The following impacts are hereby approved as long as all of the other specific and general
conditions of this Certification (or Isolated Wetland Permit) are met. No other impacts are
approved including incidental impacts:
One
N Carolina
401 Wetlands Certification Unit tllCll~~l~
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone: [phone] / FAX [phone] / Internet: http://h2o.enr.state.nc.us/ncvvetlands

Villages of Swift Creek, LLC
Page 2 of 4
12/14/04

Amount Approved Plan Location or Reference
(Units)
Stream 115 (feet) Figure #1 & 2
404 Wetlands 0.31 (acres) Figure #1
Buffers 13,709 (square ft. Figure #2

2. Erosion & Sediment Control Practices

Erosion and sediment control practices must be in full compliance with all specifications governing
the proper design, installation and operation and maintenance of such Best Management Practices in
order to protect surface waters standards:
a. The erosion and sediment control measures for the project must be designed, installed,
operated, and maintained in accordance with the most recent version of the North Carolina
Sediment and Erosion Control Planning and Design Manual.
b. The design, installation, operation, and maintenance of the sediment and erosion control
measures must be such that they equal, or exceed, the requirements specified in the most
recent version of the North Carolina Sediment and Erosion Control Manual. The devices
shall be maintained on all construction sites, borrow sites, and waste pile (spoil) projects,
including contractor-owned or leased borrow pits associated with the project.
3. No Waste, Spoil, Solids, or Fill of Any Kind

No waste, spoil, solids, or fill of any kind shall occur in wetlands, waters, or riparian areas beyond the
footprint of the impacts depicted in the Preconstruction Notice Application. All construction
activities, including the design, installation, operation, and maintenance of sediment and erosion
control Best Management Practices, shall be performed so that no violations of state water quality
standards, statutes, or rules occur.
4. No Sediment & Erosion Control Measures w/n Wetlands or Waters

Sediment and erosion control measures shall not be placed in wetlands or waters to the maximum
extent practicable. If placement of sediment and erosion control devices in wetlands and waters is
unavoidable, they shall be removed and the natural grade restored within six months of the date that
the Division of Land Resources has released the project.
5. Written Stormwater Management Plan

The final, written stormwater management plans (including a signed and notarized Operation and
Maintenance Agreement) dated October 8, 2004, must be implemented and the stormwater
management facilities shall be constructed and operational before any permanent building is occupied
at the subject site. The structural stormwater practices as approved by this Office as well as drainage
patterns must be maintained in perpetuity. No changes to the structural stormwater practices shall be
made without written authorization from the Division of Water Quality.
In an effort to comply with the diffuse flow provision of the Buffer Rule (15A NCAC 02B .0233(5)),
you have provided the DWQ with level spreader designs dated November 11, 2004 and November
29, 2004. The DWQ believes that if implemented, as per these plans, diffuse flow will be achieved.
However, if diffuse flow as per 15A NCAC 02B .0233(5) is not achieved, then the DWQ shall be
notified and corrective actions to restore diffuse flow shall be taken if necessary to impede the
formation of erosion gullies. At no time shall stormwater from the proposed development be piped
directly through the buffer without prior DWQ written authorization.

Ar
Villages of Swift Creek, LLC
Page 3 of 4
12/14/04

The Operation & Maintenance (O&M) agreement signed by the current landowner must be approved
by the DWQ. This O&M agreement must transfer with the sale of the land or transfer of
responsibility for the stormwater facilities and the DWQ must be notified of every transfer.

6. Culvert Installation

Culverts required for this project shall be installed in such a manner that the original stream profiles are
not altered. Existing stream dimensions (including the cross section dimensions, pattern, and
longitudinal profile) must be maintained above and below locations of each culvert. Culverts shall be
designed and installed to allow for aquatic life movement as well as to prevent head cutting of the
streams. If any of the existing pipes are or become perched, the appropriate stream grade shall be re-
established or, if the pipes installed in a perched manner, the pipes shall be removed and re-installed
correctly.
7. Protective Fencing

The outside buffer, wetland or water boundary and along the construction corridor within these
boundaries approved under this authorization shall be clearly marked with orange warning fencing (or
similar high visibility material) for the areas that have been approved to infringe within the buffer,
wetland or water prior to any land disturbing activities to ensure compliance with 15A NCAC 2B
.0233 and GC 3402.
8. Construction Stormwater Permit NCGO 10000

Upon the approval of an Erosion and Sedimentation Control Plan issued by the Division of Land
Resources (DLR) or a DLR delegated local erosion and sedimentation control program, an NPDES
General stormwater permit (NCGO10000) administered by DWQ is automatically issued to the
project. This General Permit allows stormwater to be discharged during land disturbing construction
activities as stipulated by conditions in the permit. If your project is covered by this permit
[applicable to construction projects that disturb one (1) or more acres], full compliance with permit
conditions including the sedimentation control plan, self-monitoring, record keeping and reporting
requirements are required. A copy of this permit and monitoring report forms may be found at
http://h2o.enr.state.ne.uslsu/Forms Documents.htm.
9. Deed Notifications

Deed notifications or similar mechanisms shall be placed on all retained jurisdictional wetlands,
waters and protective buffers in order to assure compliance for future wetland, water and buffer
impact. These mechanisms shall be put in place prior to impacting any wetlands, waters and/or
buffers approved for impact under this Certification Approval and Authorization Certificate. A
sample deed notification can be downloaded from the 401/Wetlands Unit web site at
http://h2o.enr.state.nc.us/ncwetlands. The text of the sample deed notification may be modified as
appropriate to suit to this project.
10. Notification of Construction

The applicant and/or authorized agent shall contact the DWQ Express Review Program in writing at
the letterhead address within 10 days of the commencement of construction.

11. Certificate of Completion
Upon completion of all work approved within the 401 Water Quality Certification or applicable
Buffer Rules, and any subsequent modifications, the applicant is required to return the attached

`1.
Villages of Swift Creek, LLC
Page 4 of 4
12/14/04

certificate of completion to the 401/Wetlands Unit, North Carolina Division of Water Quality, 1650
Mail Service Center, Raleigh, NC, 27699-1650.
Violations of any condition herein set forth may result in revocation of this Certification and may result in
criminal and/or civil penalties. The authorization to proceed with your proposed impacts or to conduct
impacts to waters as depicted in your application and as authorized by this Certification, shall expire upon
expiration of the 404 or CAMA permit.

If you do not accept any of the conditions of this Certification (associated with the approved wetland or
stream impacts), you may ask for an adjudicatory hearing. You must act within 60 days of the date that
you receive this letter. To ask for a hearing, send a written petition, which conforms to Chapter 150B of
the North Carolina General Statutes to the Office of Administrative Hearings, 6714 Mail Service Center,
Raleigh, N.C. 27699-6714. This certification and its conditions are final and binding unless you ask for a
hearing.
This letter completes the review of the Division of Water Quality under Section 401 of the Clean Water
Act and the Neuse riparian buffer protection rule as described within 15A NCAC 2B .0233. If you have
any questions, please telephone Cyndi Karoly at 919-733-9721 or Deborah Edwards at 919-733-9502.

Sincerely,

Alan W. Klimek, P.E.

AWK/dae

Attachments: Certificate of Completion
GC 3402

Cc: Todd Preuninger-S&EC
USACE Raleigh Regulatory Field Office
DWQ Raleigh Regional Office
DLR Raleigh Regional Office
File Copy
Central Files
Filename: 041796MirrorLake(Wake)ENF+401+buffer

~0~ WATF9Q Michael F. Easley, Governor
William G. Ross Jr., Secretary
co 7 North Carolina Department of Environment and Natural Resources
7
p Alan W. Klimek, P.E. Director
Division of Water Quality
December 3, 2004
DWQ EXP No. 04-1796
Wake County
Page 1 of 2
CERTIFIED MAIL: RETURN RECEIPT REQUESTED
Villages of Swift Creek, LLC
Attn: Jonathon Skinner
729 Thimble Shoals Blvd., Suite 6C
Newport News, VA 23606

Subject Property: Mirror Lake Subdivision

REQUEST FOR MORE INFORMATION-EXPRESS REVIEW PROGRAM

Dear Skinner:

On November 15, 2004, the Division of Water Quality (DWQ) received your application dated
November 11, 2004 to impact 0.31 acres of wetlands, 115 feet of stream and 13,709 square
feet (ft) of protected riparian buffers to construct the proposed subdivision. On November 24,
2004, the DWQ received the additional information requested from the letter dated November
19, 2004. The DWQ has determined that your application was incomplete and/or provided
inaccurate information as discussed below. The DWQ will require additional information in
order to process your application to impact protected wetland, streams and/or buffers on the
subject property. Therefore, unless we receive the additional information requested below, we
will have to move toward denial of your application as required by 15A NCAC 2H .0506 and 2B
.0233(8) and will place this project on hold as incomplete until we receive this additional
information. Please provide the following information so that we may continue to review your
project.
Additional Information:
1. Stormwater Management Plan

a. Please recalculate the SA/DA ratio; the value you provided is too low.

Please respond within three days of the date of this letter by sending this information to me via
e-mail or fax and a follow-up copy in writing. The Express Review Program is a process that
requires all parties to participate in a timely manner. If the DWQ feels the Express Review
Program is the incorrect review program for your project, then we may have to return your
application and have it reviewed through our regular 401 Water Quality Certification Program.
This letter only addresses the application review and does not authorize any impacts to
wetlands, waters or protected buffers. Please be aware that any impacts requested within your
application are not authorized (at this time) by the DWQ. Please call Cynthia Van Der Wiele at
NopfthCarolina
401 Wetlands Certification Unit atura!!y
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone: [phone] FAX [phone] / Internet: htto://h2o.enr.state.nc.us/ncwetlands
An Equal Opportunity/Aff irmative Action Employer-50% Recycled/10% Post Consumer Paper

Villages of Swift Creek, LLC
Page 2 of 2
12/3/04

[phone] if you have any questions regarding or would like to set up a meeting to discuss
this matter.

Sincerely,
n'

arol
t[an s/401 Unit,

CBK/dae

cc: Todd Preuninger-S&EC
USACE Raleigh Regulatory Field Office
DWQ Raleigh Regional Office
File Copy
Central Files
Filename: 041796MirrorLake(Wake)EXP+hold2

NCDENR
North Carolina Department of Environment and Natural Resources
Division of water Ouaitty
Michael F. Easley. Governor William G. Ross, Jr., Secretary
Alan W. Klimek, RE., Difedor
EXPRESS PERMIT REVIEW PROGRAM
Division of Water Quality
Department of Environmental and Natural Resources
Wetlands/401 Unit
Street Address: 2321 Crabtree Boulevard, Suite 250
Raleigh, NC 27604-2260
Mailing Address: 1650 Mail Service Center
Raleigh, NC 27699-1650
Conlaet Information: phone ti: 919-733.0203
Fax 9: 919-733-6693
Fax To: Jonathon SkumeT Fax [phone]
Todd Preuninger 919-546-9467
Subject: Mirror Lake Date: 12 /3/U~
Number of pages including cover sheet: 3
Notes or special instructions:
The asiginal will he sent in the snail. If you have questions please call Debbie Edwards at 919-733-9502.

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MULTI COMMUNICATION REPORT

DATE DEC-3-2004 FRI 15:.45
NAME DWQ-WETLANDS
TEL [phone]
REF. NAME

COMMUNICATION MODE: TX
NO. FAX NAME/NUMBER START TIME TIME MODE PAGE RESULTS

709 98469467 12-03 15:41 00'30" ECM 3/3 OK
709 87578730651 12-03 15:45 00'00" ECM 0/3 STOP PRESSED

TOTAL TIME : 00:00'30"
TOTAL PAGES 3

imap:Hdebbie. [e-mail]:143/...

Subject: Mirror Lake-- disregard last email
From: Cynthia Van Der Wiele <[e-mail]>
Date: Thu, 02 Dec 2004 15:21:42 -0500
To: Debbie Edwards <[e-mail]>

Yikes...I just realized I was evaluating 2 different projects...

Mirror Lake: SA/DA ratio is incorrect. DWQ calculates this to be 1.19, not 0.025.
The level spreaders are ok according to the worksheet; no plan in the packet I've got
here.
Riverwood:
1. Don't know what the cover letter means under item 1, Kevin Martin?
2. Level spreader worksheets-- calcs OK, site plan is somewhat better than last one
(you can at least see things), but with no topo, it's a guess...
3. Impervious SA estimate-- OK, will live with it and won't argue.
4. Dissipator and RCP/headwall-- good plan.
They were clipped together, so I'm not a total blonde ...C.

1 of 1 12/2/2004 4:40 PM

Project Name: Mirror Lake Pond 1
Project No. DWQ 041796

SUBMITTED DESIGN: REQUIRED DESIGN.

elevations average depth status
Bottom of Basin (ft) 403
Permanent Pool (ft) 407.5 4.5 ft. depth ok
Temporary Pool (ft) 409.5 2 ft. depth ok
areas
Permanent Pool SA (sq ft) 29055 13697 sq. ft. ok
Drainage Area (ac) 26.5 13534 based on avg depth ok
Impervious Area (ac) 10 37.7 % -

volumes
Permanent Pool (cu ft) 84663
Temporary Pool (cu ft) 53242 37480 cu. ft. ok
Forebay (cu ft) 17602 20.8 % ok
other parameters
SA/DA 0.025' 1.19 D A)07- -0.O2'S
Orifice Diameter (in) 3 cfs drawdown -
Design Rainfall (in) 1 2.6 day drawdown ok

Linear Interpolation of Correct SAIDA***
4.5 ft. Permanent Pool Depth
% Impervious SA/DA fron (Avg. Depth)
Next Lowest 30 0.97 0.96052762 1.08
Project Impervious 37.7 1.19 J. t 7 1.35
Next Highest 40 1.25 1.234499742 1.43
3 ft 4

G K
ai~

imap://[e-mail]:143/...

Subject: [Fwd: DWQ EXP No. 04-1796 - Mirror Lake Subdivision]
From: Cyndi Karoly <[e-mail]>
Date: Mon, 29 Nov 2004 09:11:12 -0500
To: debbie Edwards <[e-mail]>

Debbie - were you expecting this? There's a followup I'll forward as well.

Original Message
Subject:DWQ EXP No. 04-1796 - Mirror Lake Subdivision
Date:Wed, 24 Nov 2004 17:12:32 -0500
From:Walter Heath <WHeath(a-,)withersravenel.com>
To:<cyndi.karolyPancmail.net>
CC:<preuninger [e-mail]>

Cyndi:
Attached you will find the Mirror Lake Subdivision Express Review Submittal. As noted in the response
letter, a hard copy will be delivered to your office as well.

Feel free to give us a call with any questions, and thanks for your help!

WALTER D. HEATH IV, P .E.

WITHERS - RA'VENEL
i1a MacKenan Drive i Gary;, North Gary.)lina 27511
tel: [phone] fax. 919,467.6oc3
mobile. 9-i9.625.3090 t nextel; 27*582ti
direct: 919,535,5175
www.withersravenel.com

1 of 1 11/29/2004 9:28 AM

WITHERS R"E:NEL LETTER OF TooNSWTTQL
ENGINEERS I PLANNERS I SURVEYORS

111MacKenanDrive DATE 11.24.04 JOB NO. 203209
ATTENTION Cyndi Karoly
CARY, NORTH CAROLINA, 27511
PHONE# 1 .7 .1788
[phone] RE:
FAX [phone]oo8 Mirror Lake 401/404 permit info
To: NCDWQ - Wetlands Unit
2321 Crabtree Blvd.
Suite 250
Raleigh, NC 276o4

WE ARE SENDING YOU E Attached ? Under separate cover via the following items:
? Shop Drawings E Prints ? Plans ? Samples ? Specifications
? Copy of Letter ? Change order ? Diskette ?

COPIES DATE NO. DESCRIPTION
1 Revision letter with responses to DWQ comment
1 Revised 401 Wet Detention Basin wksht., Level spreader wksht.

1 FES#8o Level Spreader detail
1 Existing channel velocity calculations
1 11"X17" Revised Wetlands Impacts Map at 1"=50'
1 11"x17" Buffer Impacts Map at 1"=50'

1 Revised Sheet 3B showing FES#8o w/ level spreader & easement

THESE ARE TRANSMITTED as checked below:
? For approval ? Approved as submitted ? Resubmit copies for approval
? For your use ? Approved as noted ? Submit copies for distribution
? As requested ? Returned for corrections ? Return corrected prints
? For review and comment ?
? FOR BIDS DUE 20 ? PRINTS RETURNED AFTER LOAN TO US

REMARKS: This information has been emailed to you, and a hard copy will follow.

Feel free to give us a call with any questions.

COPY TO: File SIGNED: Walter D. Heath IV, P.E.
If enclosures are not as noted, kindly notify us at once.

WITHERS O'~- RAVEN EL
ENGINEERS I PLANNERS I SURVEYORS

November 24, 2004

Ms. Cyndi Karoly
Wetlands/401 Unit, DWQ
2321 Crabtree Boulevard, Suite 250
Raleigh, North Carolina 27604
RE: Responses to Buffer/Wetlands Impacts Review Comments
Mirror Lake Subdivision
DWQ Exp. No. 04-1796
W&R Project No. 203209
Dear Cyndi:

We have amended or clarified certain aspects of our Mirror Lake Subdivision Plan in order to comply
with applicable DWQ regulations. As noted on the transmittal letter, we are emailing these responses
and the associated exhibits, plans and maps to you and a hard copy will follow. Our responses to
review comments on the previous submittal are as follows:
1. Letter from the Ecosystem Enhancement Program will be provided directly to DWQ from Todd
Preuninger at S&EC.
2. Stormwater outfall has been modified to utilize a level spreader at the system exit in order to
provide diffuse flow.through the Neuse River Buffer. An additional Level Spreader Worksheet for FES
#8o and a revised Sheet 3A showing FES, level spreader and drainage easement have been included
in this package.
3. Separate wetland and buffer impact maps have been provided in this package at 1" = 50', as
requested.
4. The lot fill wetland impacts only comprise o.04 acres, not 0.26 acres as stated in your request
letter, of the total wetland impacts. Approximately 86% of the wetland impacts (0.25 acres) are due
to unavoidable roadway crossing or utility impacts.
5. Because the existing channel velocity of approximately 18 fps exceeds the proposed outlet velocity
of approximately 15 fps after culvert installation, we do not believe energy dissipation is necessary for
this application. Existing channel velocity calculations have been included in this package.
6. a. The forebay has been enlarged, and the volume now comprises 21% of the total
volume of the pond. A revised 401 Wet Detention Basin Worksheet has been
included in this package.
b. SA/DA ratio has been recalculated; new ratio is reflected in the revised 401 Wet
Detention Basin Worksheet.
Please feel free to contact us if you have any questions or require additional information regarding
this matter.
Sincerely,
WITHERS & RAVENEL, INC.

Walter D. Heath IV, P.E.

iii MacKenan Drive i Cary, North Carolina 27511 1 tel: [phone] i fax: [phone] i www.withersravenet.com

f
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\Y / \ \ \ ,5\ PF}tL\Nwk \ ' E \ ®NEIWO AREAS
\ `S~ \ i\ \ \ ? \ t\ \ \ - / ROAD Flu IMPACTS (0.7D AC)
\ \ \\41J \ t 'i \ ,\p \ / \ - ® DUTY IMPACTS (0.05 AC)
\ s\ 1y `1 \ \ S ` ~ N 7 /Ai J ^ , LOT FILL IMPACTS (0.04 AC)
t / \ \ ' 4 \ , \ / TDTAL WETLAND NFACM 0.20 AC
\ \ 1 ! L,.(`~\ \ \ \ \ \ \ \ ~ \ , / ~ \ \ \ O° \ \ 115 LF CLLVERT IMPACTS STREAM CHANNEL
1 1/ \lr\\ ` \ \ \ \ } / / J \ \ (SEE PROFILE FOR DETALM CULVERT WORMAMN)
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NON 01201

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(All NRB !FAGS CU[ TO Rao FRI.)
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Project No. DWQ (to be provided by DWQ)

DIVISION OF WATER QUALITY . 401 WET DETENTION BASIN WORKSHEET
DWQ Stormwater Management Plan Review:
1. PROJECT INFORMATION (please complete the following information):
Project Name : mig-Mor-L t,. A IC-
Contact Person: A 4. e IL a Phone Number: (9 r g ) 4.~ q . a:3, 4. o
For projects with multiple basins, sp cify which basin tfiis worksheet applies to: J / A
Basin Bottom Elevation 403.0 ft. (average elevation of the floor of the basin)
Permanent Pool Elevation 4,0 7, 5 ft. (elevation of the orifice invert out)
Temporary Pool Elevation ft. (elevation of the outlet structure invert in)

Permanent Pool Surface Area Z!1, o !j 5, sq. ft. (water surface area at permanent pool elevation)
Drainage Area 2, b. 5 ac. (on-site and off-site drainage to the basin)
Impervious Area o L c ac. (on-site and off -site drainage to the basin)
Permanent Pool Volume , 61,3 cu, ft. (combined volume of main basin and forebay)
Temporary Pool Volume S3" 2 +Z cu. ft. (volume detained on top of the permanent pool)
Forebay Volume - 17, & Q 2 - cu. ft.
SAIDA used o . o z C (surface area to drainage area ratio)
Diameter of Orifice 3 in. (draw down orifice diameter)
II. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual. Initial in the space
provided to indicate the following design requirements have been met and supporting documentation is attached. If a requirement has
not been met, attach an explanation of why. At a minimum, a complete stormwater management plan submittal includes a worksheet for
each BMP, design calculations, plans and specifications showing all BMPs and outlet structure details, a detailed drainage plan and a
fully executed operation and maintenance agreement. An incomplete submittal package will result in a request for additional Information
and will substantially delay final review and approval of the project
Appl€cants Initials
wrT?.~ The temporary pool controls runoff from the 1 inch storm event.
The basin length to width ratio is greater than 3:1.
The basin side slopes are no steeper than 3:1.
A submerged and vegetated perimeter shelf at less than 6:1 is provided.
w rwj '-Vegetation to the permanent pool elevation is specified.
b,J ___An emergency drain is provided to drain the basin.
The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet).
The temporary pool draws down In 2 to 6 days.
The forebay volume is approximately equal to 20% of the total basin volume.
Sediment storage is provided in the permanent pool.
Access Is provided for maintenance.
A notarized site specific operation and maintenance (0&M) plan Is provided.
A vegetation managemenUmovAng schedule is provided in the 0&M plan.
Semi-annual inspections are specified in the 00 plan.
A debris check Is specified in the 0&M plan to be performed after every storm event.
A specific sediment clean-out benchmark is listed (elevation or depth) in O&M plan.
w MJ A responsible party is designated in the 0&M plan.

DWQ Project No.
DIVISION OF WATER QUALITY - LEVEL SPREADER WORKSHEET

1. PROJECT INFORMATION (please complete the following information):
Project Name : rl ti V. 2 o R L. A K C
Contact Person: -.-1/A Te; rL .4 s art- Phone Number: M i q ) 464 - S 3 c
Level Spreader ID:
Level Spreader Length 50 ft. (perpendicular to flow)
Drainage Area p 67 ac. (on-site and off-site drainage to the level spreader)
Impervious Area a. 37 ac. (on-site and off-site drainage to the level spreader)
Maximum Filter Strip/Buffer Slope 5. S % (6% for forested, leaf littler cover, 8% for thick ground cover)*
grass
Max. Discharge from a 10 Year Storm 3 . I cis
Max. Discharge to Level Spreader ci$
Filter Strip/Buffer Vegetation D (thick ground cover or grass, canopied forest with leaf litter
a • v rc groundcover)
Pre-treatment or Bypass Method T_

11. REQUIRED ITEMS CHECKLIST
Initial in the space provided to indicate the following design requirements have been met and supporting documentation is attached. If a
requirement has not been met, attach an explanation of why. At a minimum, a complete stormwater management plan submittal includes
a worksheet for each BMP, design calculations, plans and specifications showing all BMPs and outlet structure details, a detailed
drainage plan and a fully executed operation and maintenance agreement, An incomplete submittal package will result in a request for
additional information and will substantially delay final review and approval of the project.
Applicants Igitials
Level spreader is at least 13 ft. per cfs for thick ground cover or grass or 100 ft per cfs in canopied forest with leaf
litter.
,,1VJ Pre-Form Scour Holes are on fiat slopes only
No structures are located in protected buffers*
If bypass method specified in the Draft Level Spreader Design Option Document:
Bypass method is specified (if applicable) and plan details and calculations are provided
Discharge to level spreader and subsequent filter strip is hydraulically and spatially separate from the bypass
discharge.
No structures are located in protected buffers.
Plan details for the bypass and outlets are provided.
The operation and maintenance agreement includes annual erosion and vegetation repair.
The operation and maintenance agreement signed and notarized by the responsible party is provided.

* Level spreaders in series can be used on slopes of up to 15% in forested areas with leaf littler cover or on slopes of up to 25% in areas
with thick ground cover or grass if designed according to the Draft Level Spreader Design Option Document. This potentially requires a
minor variance in protected buffer areas. In any event the second level spreader cannot be located in Zone 1 of a protected buffer area.

FTS #10 FES#80
T-3.6CF5
DM - 12• RCP • R
FES /80 M IP 15' RCP
TR M-1 399.90 UPSTREAM INV 432.30
T - 3.1 CFS
Dw - ts' RCP DOWNSTREAM INV 43200
MH l0A
LEVEL SPREADER SPECFMAIRM \
UENGIH - 50 FEET ? ,
FES 10
DEPTH
TH o EllI - NT FEET .
FEET RN+ce - 10
FEET
ORASS N - DO DOUBlE~ NET SLUE 12' RCP
U
CONTROL Fern EROSION 04ORT UPSTREAM INV 399.70 1 FE5 ° o G
AMERICAN CONTROL ~ ) DOWN STREAM INV 399.50
50' H \
LEVEL SPREADER DETAIL (TYP.) FES#10
1' - 20'

Trapezoidal Report

Label C Kutter's n Mannings oughnes Channel Kinematic Depth Left Right Bottom Discharge Friction Reynold Flow
oefficien oefficien oefficien Height Slope Viscosity (ft) Side Side Width (cfs) Factor Number Area
(ft) (ft/ft) (ftz/s) Slope Slope (ft) (ftZ)
(H:V)(H:V)
Trapezoidal Chann I - 1 0.030 .055000 4.00 0.90 0.90 3.00 473.42 26.4

Project Engineer: Withers & Ravenel Inc
k:\...\h&h\existing channel characteristics.fm2 Withers & Ravenel Inc FlowMaster v7.0 [7.0005]
11/24/04 05:04:06 PM ©Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA [phone] Page 1 of 2

Trapezoidal Report

Wetted Top Critical Critical Velocity Velocity Specific Froude Flow
Perimete Width Depth Slope (ft/s) Head Energy Number Type
(ft) (ft) (ft) (ft/ft) (ft) (ft)
13.76 10.20 5.60 .013363 17.93 5.00 9.00 1.97 Supercritic I

Project Engineer: Withers & Ravenel Inc
k:\...\h&h\existing channel characteristics.fm2 Withers & Ravenel Inc FlowMaster v7.0 [7.0005]
11/24/04 05:04:06 PM O Haestad Methods, Inc. 37 Brookside Road Waterbury, CT 06708 USA [phone] Page 2 of 2

11722/2004 12:17 FAX 3 DWQ DORNEY 16oo1

Soil & Environmental. Consultants, PA
11010 Raven Fid8e Road • Raleigh, N* .0 Carolina 27614 • Phone: [phone]DO Fax: {919) 846-9467
wwrw_S=dEC.com

FACSIMILE SHEET
FAX NU. (919) 8*6 9467

DATE: Project Number

TO: NAME: cc:

COMPANY-
FA.VNUMBER:

FROM SUBJECT: * n''TV'br

The following items are being, faxed: Number of pages including transmittal sheet:,,';;L_
For Your Comments/Approval For Your Information
Per Our Conversation t& Per Your Request
Please Advise _ Please Call
Would Like To Discuss Please Handle
HARD COPY SENT:
US Regular Mail Hand Delivery
Overnight No Hard Copy Sent

RENL RK& T

IF YOU HAVE ANY PROBLEMS WITH THIS TRANSMISSION, PLEASE
CONTACT AT (919) $46-5900.

#CONFIDENTIALITY NOTICE*
This transmission is intended only for tie-use of the individual or entity to which it is addressed and may contain
information that is pri-.tileged and, confirdentiat, if the reader of this message is not the intended recipient, you are hereby
notified that any disciosiue, distribution or copying of this information is strictly prohibited If you have received this .
transmission in error. please notify us it=ediately by telephone and return the faxed documents to us at the above address
via the United States Postal Service.

tte Office= Greensborq Office.
Char1Q
236 LePhillip Court, Suite C 3817-E Lawndale, Drive
Concord, NC 28025 Grrcnsbom, NC 27455
Phone, f7O41 720-9405 Phone-. [phone]
NOV-22-2004 MON 11:50 TEL:[phone] NAME:DWO-WETLANDS P. 1

1.1 22/2004 12:17 FAX DWQ DORNEY U002

NaV 1 9 2004

hem
LI I.alreffielit
PROGRAM
November 17, 2004

Todd Preuninger
Soil & Environmental Consultants, PA,
11010 Raven Ridge Road
Raleigh; NC 27614
Subject: Project: Mirror Lake Subdivision
County: Wake

The purpose of this letter is to notify you: that the North Carolina Ecosystem Enhancement Program (NCEEP) is willing to
accept payment for riparian wetland imp;3cts associated with the above referenced project. Please note that the decision
by the NCEEP to accept the mitigation ro:9uirements of this project does not assure that this payment will be approved by
the U.S. Army Corps of Engineers and tt.e N.C. Division of Water Quality Wetlands/401 Unit. It is the responsibility of
the applicant to contact these agencies to, determine if payment to the NCEEP forAmpacts associated with this project is
appropriate. .
This acceptance is valid for six months from the date of this letter. If we have not received a copy of the issued 444
Permiit/4ol Certification within this time frame, this acceptance will expire. It is the applicant's responsibility to
forward copies of the 404 Permit/401 Certification to Ecosystem Enhancernent Program in order for an invoice to be
generated-
Based on the information supplied by yo~i in a letter dated November 16, 2004, the wetlands restoration that is necessary
to satisfy the compensatory mitigation requirements for this project is summarized in the following table. The maximum
amount of miti ation that the NCEEP will acre t for this project is also indicated in this table.
Stream Riparian Wetlands Riparian Buffer
linear feet) acres (ftZ)
Impacts 0.50
Mitigation Maximum 1.0
The riparian wetlands mitigation will be provided as specified in the 401 Water Quality Certification and/or Section 404
Permit for impacts associated with the subject project in Cataloging Unit 03020201 of the Neuse Fear River Basin. The
mitigation will be performed in accordance with the Memorandum of Agreement between the N.C. Department of
Environment and Natural Resources, the U.S. Army Corps of Engineers and the N.C- Depautment of Transportation
signed July 22, 2003.
If you have any questions or need additional information, please contact Carol Shaw at [phone].
Sincerely,

ttes . Sta nfill
c Planning Supervisor
cc, Cyndi Karoly, Wetlands/401 Un,.t
Jennifer Burdette, USACOE-Ralieigh
Steve Mitchell, DWQ Regional Office-Raleigh
P "aV File
L l ~"~4~ OGLY SLR AMEHR
North Carolina !Ecosystem Enhancement Progkam, 1619 Mail Service Center, Raleigh, NG 27699-1619 / 919-733-5208 / www.noeop.net

NOV-22-2004 MON 11:50 TEL:[phone] NAME:DWO-WETLANDS P. 2

0.F W ATF9Q Michael F. Easley, Governor
,0 (i William G. Ross Jr., Secretary
C0 . North Carolina Department of Environment and Natural Resources
'-I
p Y Alan W. Klimek, P.E. Director
Division of Water Quality
'November 19, 2004
DWQ EXP No. 04-1796
Wake County
Page 1 of 2
CERTIFIED MAIL: RETURN RECEIPT REQUESTED
Villages of Swift Creek, LLC
Attn: Jonathon Skinner
729 Thimble Shoals Blvd., Suite 6C
Newport News, VA 23606

Subject Property: Mirror Lake Subdivision

REQUEST FOR MORE INFORMATION-EXPRESS REVIEW PROGRAM

Dear Skinner:

On November 15, 2004, the Division of Water Quality (DVVQ) received your application dated
November 11, 2004 to impact 0.31 acres of wetlands, 115\,feet of stream and 13,709 square
feet (ft) of protected riparian buffers to construct the proposed subdivision. The DWQ has
determined that your application was incomplete and/or provided inaccurate information as
discussed below. The DWQ will require additional information in order to process your
application to impact protected wetland, streams and/or buffers on the subject property.
Therefore, unless we receive the additional information requested below, we will have to move
toward denial of your application as required by 15A NCAC 2H .0506 and 213 .0233(8) and will
place this project on hold as incomplete until we receive this additional information. Please
provide the following information so that we may continue to review your project.
Additional Information:

1. The Express Review Program requires the final mitigation plans to be submitted with the
application. Please provide the approval letter from the Ecosystem Enhancement Program.
2. On sheet 3A, a stormwater outfall is shown approximately at lot #30 (FES80); please provide
diffuse flow provisions for this outfall.

3. Please provide an impact map on a scale of 1" = 50' for our review, the impact map that was
provided is 1" = 100'. In addition, please provide an impact map showing your riparian buffer
impacts.

4. This office believes that the lot fill of 0.26 acres of wetlands can be avoided, please
reconfigure to avoid these impacts. Please revise the plans to avoid the impacts.
5. You have indicated 115' linear feet of stream impact with a 7'x 4' box culvert at 3.91 % slope.
You have not shown the provisions for energy dissipation. Please revise the plans to include
the provisions for energy dissipation. In addition, it is recommended that baffles be used in
box culverts at significant slopes.
None Carolina
401 Wetlands Certification Unit tlt(rll$
1650 Mail Service Center, Raleigh, North Carolina 27699-1650
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone: [phone] / FAX [phone] / Internet: htti)://h2o.enr.state.nc.us/ncwetlands
An Equal Opportunity/Affirmative Action Employer - 50% Recycled/10% Post Consumer Paper

Villages of Swift Creek, LLC
Page 2 of 2
11/19/04

6. Stormwater Management Plan

a. The forebay is undersized; the;forebay must be 20% of the total volume.
b. Please recalculate the SA/DA ratio; the value you provided is too high.

Please respond within three days of the date of this letter by sending this information to me via
e-mail or fax and a follow-up copy in writing. The Express Review Program is a process that
requires all parties to participate in a timely manner. If the DWQ feels the Express Review
Program is the incorrect review program for your project, then we may have to return your
application and have it reviewed through our regular 401 Water Quality Certification Program.

This letter only addresses the application review and does not authorize any impacts to
wetlands, waters or protected buffers. Please be aware that any impacts requested within your
application are not authorized (at this time) by the DWQ. Please call Deborah Edwards at (919)
733-9502 if you have any questions regarding or would like to set up a meeting to discuss this
matter.
Sin rely,

6 f
aroly,
etl nds/401 Unit, Q.

CBK/dae
cc: Todd Preuninger-S&EC
USACE Raleigh Regulatory Field Office
DWQ Raleigh Regional Office
File Copy
Central Files
Filename: 041796MirrorLake(Wake)EXP+hold

F" : A

NCDENR
North Carolina Department of Environment and Natural Resources
Division of Water Quality
Michael F. Easley, Governor William G. Ross, Jr., Secretary
Alan W. Klimek, P.E., Director

EXPRESS PERMIT REVIEW PROGRAM

Division of Water Quality
Department of Environmental and Natural Resources
Wetlands/401 Unit

Street Address: 2321 Crabtree Boulevard, Suite 250
Raleigh, NC 27604-2260

Mailing Address: 1650 Mail Service Center
Raleigh, NC 27699-1650
Contact Information: Phone [phone]
Fax [phone]

Fax To: Jonathon Skinner Fax [phone]
Todd Preuninger 919-846-9467

Subject: Mirror Lake Date:

Number of pages including cover sheet: - 15 12`~ `.}l dc_'

Notes or special instructions:

The original will be sent in the mail. If you have questions please call Debbie Edwards at 919-733-9502.

401 Wetlands Certification Unit
1650 Mail Service Center, Raleigh, North Carolina 27699-1650 One
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604 NorthCarohna
Phone: [phone] / FAX [phone] / Internet: http://h2o.enr.state.nc.us/ncwetlands Naturallff
An Equal Opportunity/Aff irmative Action Employer - 500% Recycled/10% Post Consumer Paper

imap:Hdebbie. edwards%40dwq. [e-mail]:143/...

Subject: [Fwd: RE: Mirror Lake Subdivision EXP 04-1796]
From: Cynthia Van Der Wiele <[e-mail]>
Date: Wed, 08 Dec 2004 11:45:24 -0500
To: Debbie Edwards <[e-mail]>
Debbie,
I accept Walter Heath's explanation for the SA/DA ratio used for the Mirror Lake S/D stormwater BMPs. If tbere are no other outstanding issues, I see no other obstacle to issuing the 401 for this project.
Cynthia
Original Message ,
SubjecCRE: Mirror Lake Subdivision EXP 04-1796
Date:Mon, 6 Dec 2004 12:49:18 -0500
From:Walter Heath <WHeath(ahvithersravenel.com>
To:Cynthia Van Der Wiele <Cynthia.vanderwiele(a),ncmail.net>
CC:Cyndi Karoly <cyndi.karoly(a,ncmai1.net>1 <preuninger(i,Nandec.com>, Stephanie Hall <SHallna withersravenel.com>
Our pond sizing ended up being driven by City of Raleigh stormwater attenuation requirements rather than DWQ's surface area requirement. In meeting the City standards for attenu
The minimum SA/DA ratio given our pond's normal pool depth and impervious surface percentage is approximately 1.30. Because that SA/DA ratio would have dictated that our pond he
Thanks for your help!
Walter D. Heath IV, P.E.
Withers & Ravenel Inc.
111 MacKenan Drive. Cary, North Carolina 27511
to 1: 919.469.3340 fax: [phone]
mobile: [phone] nextel: 27.5824
direct: 919.535.5175
http://www.witheraravenel.com
-----Original Message-----
From: Cynthia Van Der Wiele [mailto:[e-mail])
Sent: Monday, December 06, 2009 9:58 AM
To: Walter Heath
Cc: Cyndi Karoly; [e-mail]; Stephanie Hall
Subject: Re: Mirror Leke Subdivision EXP 04-1796
Walter,
I don't e ae how you could be confused. With a 3' permanent pool depth
and a 508 impervious cover, 2.06 WOULD be the correct ratio, EXCEPT,
that's NOT what you've indicated on your worksheet.
You have indicated a drainage area of 26.5 acres and a impervious area
of 10 acres. This calculates to 37.7% impervious. Your permanent pool
depth is 4.5', rather than 3'. Thus, from Table 1, you can either use
the figures for 5' (round up), o average out. Thus, for 30%
impervious, you'd use 1.025 and for 40%, you'd use 1.34. Then, you
would perform a linear interpolation of those two values...
Cynthia F. Van Der Wiele, Ph.D., Environmental Engineer II
DWQ Express Review Program
TEL: [phone]
FAX: [phone]
Walter Heath wrote:
>Cynthia:
>After reviewing the attached letter, I am confused as to how you would like the SA/DA ratio presented.
>The SA/DA ratio we reported in our original submittal was 2.06, as dictated by Table 1.1 'Surface Area to Drainage Area Ratio for Permanent Pool Sizing For 858 Pollutant Removal
>Comnent #6 from DWQ's express review continent letter dated November 19, 2004 reads 'Recalculate the SA/DA ratio; the value you provided is too high.' Because we had taken the 2.
>Your most recent letter dated December 3, 2004 indicates that -the value you provided is too low,' leaving me perplexed as to how to present the SA/DA ratio information.
>Any input you may have on this matter is greatly appreciated. Thank you very much for your help!
> Walter D. Heath IV, P.E.
> With era & Ravenel Inc.
> 111 MacKenan Drive. Cary, North Carolina 27511
> t. 1: 919.469.3340 fex: 919.467.6008
mobile: [phone] nextel: 27.5824
> direct: 919.535.5175
> http://www.withersravenel.com
>-----Original Meeaege-----
>From: Debbie Edwards (mailto:[e-mail]]
>Sent: Friday, December 03, 2004 4:07 PM
>To: Walter Heath
>C C: Cyndi Karoly; Cynthia F. Van Der Wiele
>Subject: Mirror Lake Subdivision EXP 04-1796
>Walter,
>The additional information letter has been signed and faxed to the
and Todd Preuninger. I am sending you a copy via email.
>debbie
1 of 1 12/13/2004 3:47 PM

MULTI COMMUNICATION REPORT

DATE NOV-19-2004 FRI 15:14
NAME DWQ-WETLANDS
TEL [phone]
REF. NAME

COMMUNICATION MODE: TX
NO. FAX NAME/NUMBER START TIME TIME MODE PAGE RESULTS

666 98469467 11-19 15:11 00'33" ECM 3/3 OK
666 87578730651 11-19 15:12 00'57' ECM 3/3 OK

TOTAL TIME 00:01'30"
TOTAL PAGES : 6

V V~.

Project Name: Mirror Lake Pond 1 ~
Project No. DWQ 041796

SUBMITTED DESIGN: REQUIRED DESIGN:

elevations 2.9 average depth status
Bottom of Basin (ft) 403
Permanent Pool (ft) 407.5 4.5 ft. depth ok
Temporary Pool (ft) 409.5 2 ft. depth ok
areas
Permanent Pool SA (sq ft) 29055 18951 sq. ft. ok
Drainage Area (ac) 26.5 19240 based on avg depth ok
Impervious Area (ac) 10 37.7 % -
volumes
Permanent Pool (cu ft) 84663
Temporary Pool (cu ft) 53242 37480-cu. ft. ok
Forebay (cu ft) 14271 16.9% check forebc

other parameters
SA/DA 2.06 1.64 -
Orifice Diameter (in) 3 0.24 cfs drawdown -
Design Rainfall (in) 1 2.6 day drawdown ok

Linear Interpolation of Correct SAMA***
4.5 ft. Permanent Pool Depth
% Impervious SA/DA fron (Avg. Depth)
Next Lowest 30 1.34 1.36238926? 1.08
Project Impervious 37.7 1.64 1.67 1.35
Next Highest 40 1.731 1.755833704 1.43
i - Lfh

1F ~ 7

Express Review: Mirror Lake

Subject: Express Review: Mirror Lake
From: Cynthia Van Der Wiele <[e-mail]>
Date: Mon, 15 Nov 2004 17:04:00 -0500

To: Todd Preuninger <[e-mail]>
CC: Kevin Martin <[e-mail]>, Cyndi Karoly <Cyndi.Karoly @ NCMail. Net>,
Debbie Edwards <debbie.edwards @ ncmail.net>

Todd,

I am reviewing your submittal for Mirror lake. I noticed that it has a
stormwater management plan. If this is to be reviewed, it will be an
additional $2000.
You filled out an outdated version of the Initial Interest form. Please
destroy those copies and use the attached form. Also, for your information is
the currrent fee schedule.

Regards,
Cynthia F. Van Der Wiele, Ph.D.
Environmental Engineer II, DWQ Express Review Program
TEL: [phone]
FAX: [phone]

1 of 1 11/15/2004 5:05 PM

WITHERS & RAVENEL LETTER OFTRA SMMAL

ENGINEERS 1 PLANNERS 1 SURVEYORS
DATE 11.24.04 JOB No. 203209
111 MacKenan Drive ATTENTION C ndi Karol
CARY, NORTH CAROLINA, 27511 PHONE#
(919) 469'3340 919-733-1788
RE: Mirror Lake o1/ o permit info
FAX [phone]oo8
To: NCDWQ - Wetlands Unit
2321 Crabtree Blvd. E LS LC5 U V 1 C14
Suite 250
Raleigh, NC 27604 DENR-WATER QUALITY
.K tIFIXIER

WE ARE SENDING YOU ® Attached ? Under separate cover via the following items:
? Shop Drawings ® Prints ? Plans ? Samples ? Specifications
? Copy of Letter ? Change order ? Diskette ?

COPIES DATE NO. DESCRIPTION
1 Revision letter with responses to DWQ comment

1 Revised o1 Wet Detention Basin wksht., Levelspreader wksht.
1 FES#8o Level Spreader detail
1 Existing channel velocity calculations

1 11"x17" Revised Wetlands Impacts Ma at 1"= o'
1 11"xi " Buffer Impacts Ma at 1"= o'
1 Revised Sheet B showing FES#8o w/ levels reader & easement

THESE ARE TRANSMITTED as checked below:
? For approval ? Approved as submitted ? Resubmit copies for approval

? For your use ? Approved as noted ? Submit copies for distribution
? As requested ? Returned for corrections ? Return corrected prints
? For review and comment ?
? FOR BIDS DUE 20 ? PRINTS RETURNED AFTER LOAN TO US

REMARKS: This information has been emailed to you, and a hard copy will follow.

Feel free to give us a call with any questions.

COPY TO: File SIGNED: Walter D. Heath IV, P.E.

ff enclosures are not as noted, kindly notify us at once.

WITHERS L1~ RAVEN EL
ENGINEERS I PLANNERS I SURVEYORS

November 24, 2004

Ms. Cyndi Karoly
Wetlands/401 Unit, DWQ
2321 Crabtree Boulevard, Suite 250 D D
Raleigh, North Carolina 27604
RE: Responses to Buffer/Wetlands Impacts Review Comments NO V 2 9 2004
Mirror Lake Subdivision
DWQ Exp. No. 04-1796 WETLANDS TWATER ORMWUALBRANCH
W&R Project No. 203209
Dear Cyndi:

We have amended or clarified certain aspects of our Mirror Lake Subdivision Plan in order to comply
with applicable DWQ regulations. As noted on the transmittal letter, we are emailing these responses
and the associated exhibits, plans and maps to you and a hard copy will follow. Our responses to
review comments on the previous submittal are as follows:
1. Letter from the Ecosystem Enhancement Program will be provided directly to DWQ from Todd
Preuninger at S&EC.
2. Stormwater outfall has been modified to utilize a level spreader at the system exit in order to
provide diffuse flow.through the Neuse River Buffer. An additional Level Spreader Worksheet for FES
#8o and a revised Sheet 3A showing FES, level spreader and drainage easement have been included
in this package.
3. Separate wetland and buffer impact maps have been provided in this package at 1" = 5o', as
requested.
4. The lot fill wetland impacts only comprise o.o4 acres, not 0.26 acres as stated in your request
letter, of the total wetland impacts. Approximately 86% of the wetland impacts (0.25 acres) are due
to unavoidable roadway crossing or utility impacts.
5. Because the existing channel velocity of approximately 18 fps exceeds the proposed outlet velocity
of approximately 15 fps after culvert installation, we do not believe energy dissipation is necessary for
this application. Existing channel velocity calculations have been included in this package.
6. a. The forebay has been enlarged, and the volume now comprises 21% of the total
volume of the pond. A revised 401 Wet Detention Basin Worksheet has been
included in this package.
b. SA/DA ratio has been recalculated; new ratio is reflected in the revised 401 Wet
Detention Basin Worksheet.
Please feel free to contact us if you have any questions or require additional information regarding
this matter.
Sincerely,
WITHERS & RAVENEL, INC.

Walter D. Heath IV, P.E.

iii MacKenan Drive i Cary, North Carolina 27511 1 tel: [phone] I fax: [phone]oo8 i www.withersravenet.com

Project No. DWQ (to be provided by DWQ)
DIVISION OF WATER QUALITY • 401 WET DETENTION BASIN WORKSHEET
DWQ Stormwater Management Plan Review:

1. PROJECT INFORMATION (please complete the following information):
Project Name : "I R. R 0 R.. t -A K
Contact Person: w A 4 & IL 6 A .:r Number. (9 1 4 ) 4-f. g .-3:3 4 o
For projects with multiple basins, sp ciy which basin is worksheet applies to: J1 A
Basin Bottom Elevation A-03, o ft. (average elevation of the floor of the basin)
Permanent Pool Elevation .40 7. S ft. (elevation of the orifice invert out)
Temporary Pool Elevation 4 o 11. S ft. (elevation of the outlet structure invert in)
Permanent Pool Surface Area 29, p 5 sq. ft. (water surface area at permanent pool elevation)
Drainage Area 2 6. K ac. (on-site and off-site drainage to the basin)
Impervious Area o . o ac. (on-site and off--site drainage to the basin)

Permanent Pool Volume rid, 6 3 cu. ft. (combined volume of main basin and forebay)
Temporary Pool Volume 99>, 242. cu. ft. (volume detained on top of the permanent pool)
Forebay Volume _ 17, b o 2 , cu. ft.
SAIDA used 0.02.5 (surface area to drainage area ratio)
Diameter of Orifice 3 in. (draw down orifice diameter)
11. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual. Initial in the space
provided to indicate the following design requirements have been met and supporting documentation is attached. If a requirement has
not been met, attach an explanation of why. At a minimum, a complete stormwater management plan submittal includes a worksheet for
each BMP, design calculations, plans and specifications showing all BMPs and outlet structure details, a detailed drainage plan and a
fully executed operation and maintenance agreement. An incomplete submittal package will result in a request for additional information
and will substantially delay final review and approval of the project
Applicants Initials
The temporary pool controls runoff from the 1 inch storm event.
The basin length to width ratio is greater than 3:1.
The basin side slopes are no steeper than 3:1.
A submerged and vegetated perimeter shelf at less than 6:1 is provided.
w n( ~ Vegetation to the permanent pool elevation is specified.
V%, b SA An emergency drain is provided to drain the basin.
The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet).
The temporary pool draws down in 2 to 5 days.
The forebay volume is approximately equal to 20% of the total basin volume.
Sediment storage is provided in the permanent pool.
Access is provided for maintenance.
A notarized site specific operation and maintenance (0&M) plan is provided.
W bpi A vegetation management/mowing schedule is provided in the 0&M plan.
Semi-annual inspections are specified in the 0&M plan.
A debris check is specified in the 0&M plan to be performed after every storm event.
A specific sediment clean-out benchmark is listed (elevation or depth) in 0&M plan.
V., MA A responsible party is designated in the 0&M plan.
D CC~L~~b[~ p
NOV292004
DENR - WATER QUALITY
WETLANDS AND STORMWATER BRANCH

DWQ Project No.

DIVISION OF WATER QUALITY - LEVEL SPREADER WORKSHEET

1. PROJECT INFORMATION (please complete the following information):
Project Name : H I R e o R 1. A it E
Contact Person: tiA LTE rL AE AT Phone Number: (919 ) 464 - 33$c
Level Spreader ID:
Level Spreader Length 50 ft. (perpendicular to flow)
Drainage Area o-67 ac. (on-site and off-site drainage to the level spreader)
Impervious Area P. 37 ac. (on-site and off-site drainage to the level spreader)
Maximum Filter Strip/Buffer Slope 5.6 % (6% for forested, leaf littler cover, 8% for thick ground cover)*
grass
Max. Discharge from a 10 Year Storm . I cfs
Max. Discharge to Level Spreader a. I cf$
Filter Strip/Buffer Vegetation .1,- 4 V-. J ~J > (thick ground cover or grass, canopied forest with leaf litter
c. v & P- groundcover)
Pre-treatment or Bypass Method 4

II. REQUIRED ITEMS CHECKLIST
Initial in the space provided to indicate the following design requirements have been met and supporting documentation is attached. If a
requirement has not been met, attach an explanation of why. At a minimum, a complete stormwater management plan submittal includes
a worksheet for each BMP, design calculations, plans and specifications showing all BMPs and outlet structure details, a detailed
drainage plan and a fully executed operation and maintenance agreement. An incomplete submittal package will result in a request for
additional information and will substantially delay final review and approval of the project.
Applicants lyitials
Level spreader is at least 13 ft. per cfs for thick ground cover or grass or 100 ft per cfs in canopied forest with leaf
litter.
Pre-Form Scour Holes are on flat slopes only
No structures are located in protected buffers*
If bypass method specified in the Draft Level Spreader Design Option Document:
411 Bypass method is specified (if applicable) and plan details and calculations are provided
Discharge to level spreader and subsequent filter strip is hydraulically and spatially separate from the bypass
discharge.
No structures are located in protected buffers.
Plan details for the bypass and outlets are provided.
The operation and maintenance agreement includes annual erosion and vegetation repair.
The operation and maintenance agreement signed and notarized by the responsible party is provided.
* Level spreaders in series can be used on slopes of up to 15% in forested areas with leaf littler cover or on slopes of up to 25% in areas
with thick ground cover or grass if designed according to the Draft Level Spreader Design Option Document. This potentially requires a
minor variance in protected buffer areas. In any event the second level spreader cannot be located in Zone 1 of a protected buffer area.

o 11

C1
N 'a
c,
30
O Z tZQq
O G3j
FES 10
Q - a8 CFS
OIA - 12• RCP " R
FES 80 S 1 15" RCP
D TR 399.90 UPSTREAM INV 432.30
dIA - - a1 15• cFS RCP DOWNSTREAM INV 432.00
MH t0A ~
LEVEL SPREADER SPECIFICATIONS
LENGTH - 80 FEET FES 10
DEPTH - 0.8 FEET • .
WIDTH 0 ENTRANCE - 10
FEET
LINER -DOUBLE NET S 12" RCP -..s0' N EROSION COCONCONTROUTL BLANKET (NORTH UPSTREAM INV 399.70
AMERICAN GREEN 0380) DOWNSTREAM INV 399.50 / I
1 \ FES 8 01
50,

LEVEL SPREADER DETAIL MR)
1 "=20'

Label C Kutter's n Mannings oughne Channel Kinematic Depth Left Right Bottom Discharge Friction Reynold Flow
oefficien oefficien oefficien Height Slope Viscosity (ft) Side Side Width (cfs) Factor Number Area
(ft) (ft/ft) (ftZ/s) Slope Slope (ft) (ft2)
(H:V)(H:V)
Trapezoidal Chann 0.030 ).055000 4.00 0.90 0.90 3.00 473.42 26.4

-e«eU i.N -"-ai -Uuw veioCmyveioc yupec c rou-e i iow
Perimete Width Depth Slope (fUs) Head Energy t umbe Type
• ` (ft) (ft) (ft) (ft/ft) (ft) (ft)
13.76 10.20 5.60 ).013363 1793 5.00 9.00 1.97 Supercritia

YSoil & En4dronmental Consultants, PA
11010 Raven Ridge Road Raleigh, North Carolina 27614 • Phone: [phone] Fax: [phone]
www.SandEC.com

November 11, 2004
QUALITY

US Army Corps of Engineers NCDWQ
Attn: Ms. Jennifer Burdette Attn: Ms. Debbie Edwards
6508 Falls of the Neuse Rd., Ste. 120 2321 Crabtree Blvd., Suite 250
Raleigh, NC 27615 Raleigh, NC 27604-2260

p p4-179b

RE: Nationwide Permits 12 and 39, 401 Certification, and Buffer Cot@@
Q V
Mirror Lake Subdivision
Raleigh, Wake County, North Carolina NOV 1. 5 2004
S&EC Project 8666.W2
DENR - WATER QUALITY
WETLANDS AND STORMWATER WW"
Dear Ms. Burdette and Ms. Edwards,

On behalf of The Villages of Swift Creek LLC (Attn: Mr. Jonathon Skinner), we hereby
request authorization from the US Army Corps of Engineers to use Nationwide Permits
12 and 39 to cover impacts to jurisdictional wetlands and stream channels (see attached
overall map). We are also requesting approval from the NCDWQ for impacts to
jurisdictional streams, wetlands and riparian buffers. A Pre-construction Notification
Application (PCN) is attached, which includes an agent authorization form. Data forms
are included to support for the wetland delineation.

The proposed project consists of impacts from the construction of a thoroughfare road
and utility lines for a residential housing development. The subject site is located on
Tryon Road, just east of the intersection of Tryon Road and Lake Dam Road in Wake C a
County, North Carolina. The site is approximately 28 acres in size. Please refer to the r-
attached USGS map, which displays the location of the proposed project. j '

S&EC conducted a detailed wetland delineation and Neuse Buffer evaluation in April
2004. We have included a copy of the delineation map for approval.

The applicant requested a detailed wetland. delineation and buffer evaluation on the
property prior to site plan development in order to avoid jurisdictional features and

Charlotte Office: Greensboro Office:
236 LePhillip Court, Suite C 3817-E Lawndale Drive
Concord, NC 28025 Greensboro, NC 27455
Phone: [phone] Phone:. [phone]
Fax: [phone] Fax: [phone]

~ _

S

F

i

riparian buffers to the maximum extent practicable. The proposed utility line (Impact
1) will temporarily impact approximately 0.05 acres of jurisdictional wetlands. The
proposed road and lot fill (Impacts 2/3) will impact 115 linear feet of perennial
stream channel and 0.26 acres of wetland. Riparian buffer impacts consist of 13,709
sq. ft. (Zl: 7,909 SF, Z2: 5,800). These impacts are elaborated upon within the attached
PCN form and are shown on the attached inset impaj~ maps.

A perennial stream bisects the property. In order to access high ground in the southern
portion of the property, impacts are unavoidable. Moreover, the City of Raleigh is
requiring that Gorman Street be extended as Part of the CAMPO thoroughfare plan.
Impacts were minimized through the use of headwalls, retaining walls and 2:1 fill slopes.
For additional information please refer to the attached letter from the project engineer
(dated October 26, 2004).
The USACE's current policy requires applicants to avoid and minimize wetland and
stream channel impacts to the maximum extent practicable and compensatory mitigation
to offset unavoidable losses of waters of the US when impacts exceed the requirements
for notification (0.10 acre). The proposed road is necessary to access the entire property
and is required by the City of Raleigh. Because the permanent wetland impacts exceed
0.10 acres (total = 0.26), the applicant proposes payment into the ecosystem enhancement
program to satisfy mitigation requirements in the amount of 0.5 acres. The request for
payment has been forwarded to EEP concurrent with this application. Perennial stream
impacts are less than 150 linear feet; therefore, we do not believe stream mitigation
should be required.

Impervious surface is approximately 58% of the total 'acreage on the site. In order to treat
stormwater runoff, the applicant has provided a wet pond and forested filter strip to aid in
nutrient removal. We have provided stormwater plans, worksheets and the operation and
maintenance agreement for review by the NC-DWQ.

Sincerely,

Todd Preuninger
Biologist/Project Manager

Attachments:
Pre-construction (PCN) notification form
USGS Site Vicinity Map
Wake County Soil Survey Map
Impact reference map and details
Wetland Data Forms
Agent Authorization form
wetland Delineation Map
DWQ stormwater worksheets
Operations and Maintenance Agreement

Office Use Only: Form Version May 2002

-1796
USACE Action ID No. DWQ r" O
(If any particular item is not applicable to this project, please enter "Not Applicable" or "N/A".)
1. Processing

1. Check all of the approval(s) requested for this project:
® Section 404 Permit ® Riparian or Watershed Buffer Rules
? Section 10 Permit ? Isolated Wetland Permit from DWQ
® 401 Water Quality Certification

2. Nationwide, Regional or General Permit Number(s) Requested: NWP 12 & 39

3. If this notification is solely a courtesy copy because written approval for the 401 Certification
is not required, check here: ?

4. If payment into the North Carolina Wetlands Restoration Program (NCWRP) is proposed for
mitigation of impacts (verify availability with NCWRP prior to submittal of PCN), complete
section VIII and check here: ?

5. If your project is located in any of North Carolina's twenty coastal counties (listed on page
4), and the project is within a North Carolina Division of Coastal Management Area of
Environmental Concern (see the top of page 2 for further details), check here: ?

II. Applicant Information

1. Owner/Applicant Information
Name: Jonathan Skinner
Mailing Address: The Villages of Swift Creek, LLC
729 Thimble Shoals Blvd.
Suite 6C
Newport News, VA 23606
Telephone Number: [phone] Fax Number: [phone]
E-mail Address:
2. Agent/Consultant Information (A signed and dated copy of the Agent Authorization letter
must be attached if the Agent has signatory authority for the owner/applicant.)
Name: Todd Preuninger
Company Affiliation: Soil & Environmental Consultants, PA
Mailing Address: 11010 Raven Ridge Road
Raleigh, NC 27614

Telephone Number: [phone] Fax Number: [phone]
E-mail Address: preuninger (cDsandec.com

Page 1 of 8

III. Project Information

Attach a vicinity map clearly showing the location of the property with respect to local
landmarks such as towns, rivers, and roads. Also provide a detailed site plan showing property
boundaries and development plans in relation to surrounding properties. Both the vicinity map
and site plan must include a scale and north arrow. The specific footprints of all buildings,
impervious surfaces, or other facilities must be included. If possible, the maps and plans should
include the appropriate USGS Topographic Quad Map and NRCS Soil Survey with the property
boundaries outlined. Plan drawings, or other maps may be included at the applicant's discretion,
so long as the property is clearly defined. For administrative and distribution purposes, the
USACE requires information to be submitted on sheets no larger than 11 by 17-inch format;
however, DWQ may accept paperwork of any size. DWQ prefers full-size construction
drawings rather than a sequential sheet version of the full-size plans. If full-size plans are
reduced to a small scale such that the final version is illegible, the applicant will be informed that
the project has been placed on hold until decipherable maps are provided.

1. Name of project: Mirror Lake Subdivision

2. T.I.P. Project Number or State Project Number (NCDOT Only): N/A

3. Property Identification Number (Tax PIN): 0782.12 86 0914

4. Location
County: Wake Nearest Town: Raleigh. NC
Subdivision name (include phase/lot number): Mirror Lake
Directions to site (include road numbers, landmarks, etc.): The subject property is
located on Tryon Road, just east of the intersection of Tryon Road and Lake Dam
Road in Wake County. North Carolina.

5. Site coordinates, if available (UTM or Lab/Long): 35.7463152 N. 78.7019014 E
(Note - If project is linear, such as a road or utility line, attach a sheet that separately lists the
coordinates for each crossing of a distinct waterbody.)

6. Property size (acres): 28

7. Nearest body of water (stream/river/sound/ocean/lake): Lake Johnson
8. River Basin: Neuse
(Note - this must be one of North Carolina's seventeen designated major river basins. The
River Basin map is available at hU://h2o.enr.state.nc.us/admin/mVs/.)

9. Describe the ekisting conditions on the site and general land use in the vicinity of the project
at the time of this application: The site is currently wooded and consists primarily of
mixed pine/hardwood forest.

Page 2 of 8

10. Describe the overall project in detail, including the type of equipment to be used:
The project consists of the construction of town homes, an offsite wet-pond
level spreader and sanitary sewer pump station. Heavy equipment associated with
grading and construction will be utilized In addition the City of Raleigh is requiring
that Gorman Street be extended to the south as part of CAMPO's comprehensive
Thoroughfare Plan.

11. Explain the purpose of the proposed work: The proposed work is needed to meet the
housing demand in the area.

IV. Prior Project History

If jurisdictional determinations and/or permits have been requested and/or obtained for this
project (including all prior phases of the same subdivision) in the past, please explain. Include
the USACE Action ID Number, DWQ Project Number, application date, and date permits and
certifications were issued or withdrawn. Provide photocopies of previously issued permits,
certifications or other useful information. Describe previously approved wetland, stream and
buffer impacts, along with associated mitigation (where applicable). If this is a NCDOT project,
list and describe permits issued for prior segments of the same T.I.P. project, along with
construction schedules.
S&EC conducted a detailed wetland delineation in April 2004. The delineation map will
be sent concurrently with the PCN form for Corps approval.

V. Future Project Plans

Are any future permit requests anticipated for this project? If so, describe the anticipated work,
and provide justification for the exclusion of this work from the current application.
No additional impacts are anticipated.

VI. Proposed Impacts to Waters of the United States/Waters of the State

It is the applicant's (or agent's) responsibility to determine, delineate and map all impacts to
wetlands, open water, and stream channels associated with the project. The applicant must also
provide justification for these impacts in Section VII below. All proposed impacts, permanent
and temporary, must be listed herein, and must be clearly identifiable on an accompanying site
plan. All wetlands and waters, and all streams (intermittent and perennial) must be shown on a
delineation map, whether or not impacts are proposed to these systems. Wetland and stream
evaluation and delineation forms should be included as appropriate. Photographs may be
included at the applicant's discretion. If this proposed impact is strictly for wetland or stream
mitigation, list and describe the impact in Section VIII below. If additional space is needed for
listing or description, please attach a separate sheet.
1. Provide a written description of the proposed impacts: The proposed impacts consist of
0.31 acres of wetlands (0.26 permanent + 0.05 temporary), 115 linear feet of
perennial stream impact and 0.31 acres of riparian buffer impact.

Page 3 of 8

2. Individually list wetland impacts below:

Wetland Impact Area of Located within Distance to
Site Number Type of Impact* Impact 100-year Floodplain** Nearest Stream Type of Wetland***
indicate on ma acres es/no (linear feet .
Impact 1 (NWP12) Temporary 0.05 No -100. Bottomland Hardwood
Impact 2/3 (NWP 39) Fill (permanent) 0.26 No 0-20 Bottomland Hardwood
* List each impact separately and identify temporary impacts. Impacts include, but are not limited to: mechanized clearing, grading, fill,
excavation, flooding, ditching/drainage, etc. For dams, separately list impacts due to both structure and flooding.
100-Year floodplains are identified through the Federal Emergency Management Agency's (FEMA) Flood Insurance Rate Maps
(FIRM), or FEMA-approved local floodplain maps. Maps are available through the FEMA Map Service Center at 1-800-358-9616, or
online at http://www.femagov.
List a wetland type that best describes wetland to be impacted (e.g., freshwater/saltwater marsh, forested wetland, beaver pond,
Carolina Bay, bog, etc.) Indicate if wetland is isolated (determination of isolation to be made by USACE only).
List the total acreage (estimated) of all existing wetlands on the property: 0.92 Acres
Total area of wetland impact proposed: 0.26 + 0.05 temp.= 0.31 Acres
3. Individually list all intermittent and perennial stream impacts below:

Stream Impact Length of Average Width Perennial or
Site Number Type of Impact* Impact Stream Name** of Stream Intermittent?
indicate on ma linear feet Before Im act leasespecify)
Impact 4 (NWP39) Culvert 115 UT to 3-5 Perennial
* List each impact separately and identify temporary impacts. Impacts include, but are not limited to: culverts and associated rip-rap,
dams (separately list impacts due to both structure and flooding), relocation (include linear feet before and after, and net loss/gain),
stabilization activities (cement wall, rip-rap, crib wall, gabions, etc.), excavation, ditching/straightening, etc. If stream relocation is
proposed, plans and profiles showing the linear footprint for both the original and relocated streams must be included
Stream names can be found on USGS topographic maps. If a stream has no name, list as UT (unnamed tributary) to the nearest
downstream named stream into which it flows. USGS maps are available through the USGS at 1-800-358-9616, or online at
www.usgs.eov. Several internet sites also allow direct download and printing of USGS maps (e.g., www.Wgzone.com,
www.maNuest.com, etc.).
Cumulative impacts (linear distance in feet) to all streams on site: 115 linear feet
4. Individually list all open water impacts (including lakes, ponds, estuaries, sounds, Atlantic
Ocean and any other water of the U.S.) below:
Open Water Impact Area of Name Type of Waterbody
Site Number Type of Impact* Impact Wate) (lake, pond, estuary , sound,
indicate on ma acres (if applicable) bay, ocean, etc.
NA NA NA NA NA
* List each impact separately and identify temporary impacts. Impacts include, but are not limited to: fill, excavation, dredging,
flooding, drainage, bulkheads, etc.
5. Pond Creation
If construction of a pond is proposed, associated wetland and stream impacts should be
included above in the wetland and stream impact sections. Also, the proposed pond should
be described here and illustrated on any maps included with this application.
Pond to be created in (check all that apply): ? uplands ? stream ? wetlands

Page 4 of 8

Describe the method of construction (e.g., dam/embankment, excavation, installation of
draw-down valve or spillway, etc.): NA

Proposed use or purpose of pond (e.g., livestock watering, irrigation, aesthetic, trout pond,
local stormwater requirement, etc.): NA

Size of watershed draining to pond: NA Expected pond surface area: NA

VII. Impact Justification (Avoidance and Minimization)

Specifically describe measures taken to avoid the proposed impacts. It may be useful to provide
information related to site constraints such as topography, building ordinances, accessibility, and
financial viability of the project. The applicant may attach drawings of alternative, lower-impact
site layouts, and explain why these design options were not feasible. Also discuss how impacts
were minimized once the desired site plan was developed. If applicable, discuss construction
techniques to be followed during construction to reduce impacts.

The applicant requested a detailed delineation prior to site plan development in
order to avoid or reduce impacts. However, a perennial stream bisects the property. In
order to access high ground in the southern portion of the property, impacts are
unavoidable. Moreover, the City of Raleigh is requiring that Gorman Street be extended
as Part of the CAMPO thoroughfare plan. Impacts were minimized through the use of
headwalls, retaining walls and 2:1 fill slopes. For additional information please refer to
the attached letter from the project engineer (dated October 26, 2004).

VIII. Mitigation

DWQ - In accordance with 15A NCAC 2H .0500, mitigation may be required by the NC
Division of Water Quality for projects involving greater than or equal to one acre of impacts to
freshwater wetlands or greater than or equal to 150 linear feet of total impacts to perennial
streams.

USACE - In accordance with the Final Notice of Issuance and Modification of Nationwide
Permits, published in the Federal Register on March 9, 2000, mitigation will be required when
necessary to ensure that adverse effects to the aquatic environment are minimal. Factors
including size and type of proposed impact and function and relative value of the impacted
aquatic resource will be considered in determining acceptability of appropriate and practicable
mitigation as proposed. Examples of mitigation that may be appropriate and practicable include,
but are not limited to: reducing the size of the project; establishing and maintaining wetland
and/or upland vegetated buffers to protect open waters such as streams; and replacing losses of
aquatic resource functions and values by creating, restoring, enhancing, or preserving similar
functions and values, preferable in the same watershed.
If mitigation is required for this project, a copy of the mitigation plan must be attached in order
for USACE or DWQ to consider the application complete for processing. Any application
lacking a required mitigation plan or NCWRP concurrence shall be placed on hold as

Page 5 of 8

incomplete. An applicant may also choose to review the current guidelines for stream restoration
in DWQ's Draft Technical Guide for Stream Work in North Carolina, available at
hiLtp://h2o.enr.state.nc.us/ncwetlands/strmp,ide.html.

1. Provide a brief description of the proposed mitigation plan. The description should provide
as much information as possible, including, but not limited to: site location (attach directions
and/or map, if offsite), affected stream and river basin, type and amount (acreage/linear feet)
of mitigation proposed (restoration, enhancement, creation, or preservation), a plan view,
preservation mechanism (e.g., deed restrictions, conservation easement, etc.), and a
description of the current site conditions and proposed method of construction. Please attach
a separate sheet if more space is needed.
Because the permanent wetland impacts exceed 0.10 acres (total = 0.26). the
applicant proposes payment into the ecosystem enhancement program to satisfy
mitigation requirements in the amount of 0.5 acres. The request for payment has
been forwarded to EEP concurrent with this application. Perennial stream impacts
are less than 150 linear feet, therefore, we do not believe stream mitigation should
be required.

2. Mitigation may also be made by payment into the North Carolina Wetlands Restoration
Program (NCWRP). Please note it is the applicant's responsibility to contact the NCWRP at
[phone] to determine availability and to request written approval of mitigation prior
to submittal of a PCN. For additional information regarding the application process for the
NCWRP, check the NCWRP website at ho://h2o.enr.state.nc.us/wrp/index.htm. If use of
the NCWRP is proposed, please check the appropriate box on page three and provide the
following information:

Amount of stream mitigation requested (linear feet): N/A
Amount of buffer mitigation requested (square feet): N/A
Amount of Riparian wetland mitigation requested (acres): 0.5
Amount of Non-riparian wetland mitigation requested (acres): N/A
Amount of Coastal wetland mitigation requested (acres): N/A

IX. Environmental Documentation (required by DWQ)

Does the project involve an expenditure of public (federal/state) funds or the use of public
(federal/state) land?
Yes ? No
If yes, does the project require preparation of an environmental document pursuant to the
requirements of the National or North Carolina Environmental Policy Act (NEPA/SEPA)?
Note: If you are not sure whether a NEPA/SEPA document is required, call the SEPA
coordinator at [phone] to review current thresholds for environmental documentation.
Yes El No

Page 6 of 8

If yes, has the document review been finalized by the State Clearinghouse? If so, please attach a
copy of the NEPA or SEPA final approval letter.
Yes ? No ?

X. Proposed Impacts on Riparian and Watershed Buffers (required by DWQ)

It is the applicant's (or agent's) responsibility to determine, delineate and map all impacts to
required state and local buffers associated with the project. The applicant must also provide
justification for these impacts in Section VII above. All proposed impacts must be listed herein,
and must be clearly identifiable on the accompanying site plan. All buffers must be shown on a
map, whether or not impacts are proposed to the buffers. Correspondence from the DWQ
Regional Office may be included as appropriate. Photographs may also be included at the
applicant's discretion.

Will the project impact protected riparian buffers identified within 15A NCAC 2B .0233
(Neese), 15A NCAC 2B .0259 (Tar-Pamlico), 15A NCAC 2B .0250 (Randleman Rules and
Water Supply Buffer Requirements), or other (please identify 1?
Yes ® No ? If you answered "yes", provide the following information:

Identify the square feet and acreage of impact to each zone of the riparian buffers. If buffer
mitigation is required calculate the required amount of mitigation by applying the buffer
multipliers. Required

Zone* Impact
uare feet Multiplier Mitigation
1 7,909 3 N/A
2 5,800 1.5 N/A
Total 13,709 N/A
* Zone 1 extends out 30 feet perpendicular from near bank of channel; Zone 2 extends an
additional 20 feet from the edge of Zone 1.
If buffer mitigation is required, please discuss what type of mitigation is proposed (i.e., Donation
of Property, Conservation Easement, Riparian Buffer Restoration / Enhancement, Preservation or
Payment into the Riparian Buffer Restoration Fund). Please attach all appropriate information as
identified within 15A NCAC 2B .0242 or.0260.
N/A

XI. Stormwater (required by DWQ)

Describe impervious acreage (both existing and proposed) versus total acreage on the site.
Discuss stormwater controls proposed in order to protect surface waters and wetlands
downstream from the property.
Impervious surface is approximately 58% of the total acreage on the site. In order to
treat stormwater runoff, the applicant has provided a wet pond and forested filter strip to
aid in nutrient removal. We have provided stormwater plans, worksheets and the
operation and maintenance agreement for your review.

Page 7 of 8

XH. Sewage Disposal (required by DWQ)

Clearly detail the ultimate treatment methods and disposition (non-discharge or discharge) of
wastewater generated from the proposed project, or available capacity of the subject facility.
Sanitary sewer system.

X1II. Violations (required by DWQ)

Is this site in violation of DWQ Wetland Rules (15A NCAC 2H .0500) or any Buffer Rules?
Yes ? No

Is this an after-the-fact permit application?
Yes ? No

XIV. Other Circumstances (Optional):

It is the applicant's responsibility to submit the application sufficiently in advance of desired
construction dates to allow processing time for these permits. However, an applicant may
choose to list constraints associated with construction or sequencing that may impose limits on
work schedules (e.g., draw-down schedules for lakes, dates associated with Endangered and
Threatened Species, accessibility problems, or other issues outside of the applicant's control).

Applicant/Agent's Signature ate
(Agent's signature is valid only if an authorization letter from the applicant is provided.)

Page 8 of 8

WITHERS RAVEN EL

ENGINEERS I PLANNERS I SURVEYORS

October 26, 2004

Mr. Todd Preuninger
Soil & Environmental Consultants
iioio Raven Ridge Road
Raleigh, North Carolina 27614
RE: Mirror Lake Subdivision (formerly Watts Chapel)
W&R Project #203209

Mr. Preuninger:

At your request we prepared this letter to provide information regarding the project's proposed
wetland & riparian buffer impacts. We understand this information is required for the review and
approval.. of the proposed impacts by the US Army Corps of Engineers and the North Carolina
Department of Environment and Natural Resources.
The proposed project lies within the Neuse River basin and consists of ±69 single-family home sites
and ±96 multi-family units on approximately 28 acres. An additional t3.5 acres offsite will be
utilized for a wet pond, level spreader and sanitary sewer pump station. The proposed project on-
site impervious surface percentage is approximately 58% including the associated open space
dedication. We have provided a proposed impact map for the only wetland impact on the project,
which occurs in the vicinity of the Gorman Street thoroughfare crossing.

The perennial stream channel impacted by the Gorman Street crossing bisects the site from west to
east. The road crossing is required by the City of Raleigh as part of CAMPO'S comprehensive
Thoroughfare Plan, which includes the extension of Gorman Street to the south as shown. The
roadway width is also dictated by the City of Raleigh, which to a great extent dictates the length of
the proposed culvert length and subsequent channel and wetlands impacts. The road crossing is
located in as perpendicular a fashion as possible to minimize stream channel impacts. Other
practices utilized to minimize impacts include 2:1 fill slopes, culvert headwalls, and extensive use of
retaining walls.
A wet pond and level spreader in series are utilized to achieve appropriate water quantity and
quality treatment. Storms greater than 1" per hour in intensity bypass the level spreader through a
rip-rap lined spillway. The discharge to the level spreader from the pond is hydraulically and
spatially separate from the bypass discharge. Applicable calculations, worksheets and details have
been included in this package.
We trust the above information will assist in your obtaining disturbance permits for the proposed
project. Please advise should you require any additional information.

Sincerely,
WITHERS & RAVENEL, INC.

Walter D. Heath IV, P.E.

iii Macl(enan Drive i Cary, North Carolina 27511 1 tel: [phone] i fax: [phone]oo8 i www.withersravenet.com

tu/ZU/ZUU4 08:16 FAA. , WITHERS 10003

• Soil & Environmental Consultants, PA,
11010 Raved Ridge Road • Raleigh, North Carolina 27614 • Phone: [phone] Fax: [phone]
www.SandEC.corn

AGENT AUTHORIZATION FORM
All Blanks To Be Fffled In By The Current Landowner

Name: ~oNRItIA?J SWNt.1P N
Address: -721 inn I 214- SvAe- V_, Ne.wf6YA Hems, VA, 366iv

Phone: 7S---7- 9--73- 001k

Project Name/ Description:
Date: Io J 2b o~}

The Department of the Army
U.S. Army Corps of Engineers, WImington District
P.O. Box 1890
Wilmington, NC 28402

Attn:
Fi.eld Office:
Re: Wetlands Related Consulting and Permitting

To Whom It May Concern:

I, the current zo owner, hereby designate and authorize Soil & Environmental Consultants, PA to
act in my behalf as my agent in the processing of permit applications, to furnish upon request
supplemental information_ ,mot support of applications, etc. from this day forward. The 2 6'A day of

This notification supersedes any previous correspondence concerning the agent for this project

NOTICE: This authorization, for liability and professional courtesy reasons, is valid only for
government officials to enter the property when accompanied by S&EC staff. You should call S&EC
to arrange a site meeting prior to visiting the site.,

Vd N ATttfl N IP S1~t N N E12
Print Property Owner's Name Pz riy Owner's Signature

cc: Mr. John Dorney cc: Mr.. Todd Preuninger
NCDENR - OWQ Soil & Environmental Consultants, PA
2321 Crabtree Boulevard
Raleigh, NC 27604

rlOt[C OffIC~'.: C Sbm Office:
236 LePhillip Covet. Suite C 3817-E Utwndalc Drive '
Concord, NC 28025 Greensboro, NC 27455
Phone: [phone] Phone::[phone]
Fax: [phone]
FaY• f7t14172t?-9406

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71 6 } 1 5 11 1 4i LOT FILL IMPACTS (0.04 AC)
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` ZONE 1 NRB IMPACTS: 7,909 SF
t ! I , I ? ` \ ` ZONE 2 NRB IMPACTS: 5.800 SF
1 t ` \ ` TOTAL NR8 IMPACTS: 13,709 SF (0.31 AC)
115 LF CULVERT IMPACTS STREAM CHANNEL
- - - ( 1 (SEE PROFILE FOR DETAILED CULVERT INFORMATION)
WITHERS RAVENEL "11/04 MIRROR LAKE
EJ{GIJ{EERS 1 PLANNERS I SURVEYORS 1"-100'HORZ. WETLANDS AND BUFFER IMPACTS
I I MacKmn Drive Gry, North Grulim 27511 lei: 919-169-3340 fm 919467.WW -,t,~-A~ WDH RALEIGH NORTH CAROLINA

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1111/04 MIRROR LAKE

ENGINEERS I WITHERS PLANNERS I SURVEYORS EL ,"a 1so'H;,°-sIv STREAM CROSSING CROSS-SECTION
111 MacKenan Drive Cary, North Carolina 27511 te1: 919-069-3340 fax: 919L467-6008 www.withemma el.com WDH RALEIGH NORTH CAROLINA

CONSERVATION POOL aptp
SPREC~AS'i REMIFORC~~
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1/4 *x 2' STEEL. STRAP W
2 - 3/4' ANCHOR DOLTS
2 STRAPS REQb
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PLACE STEM SUPPORTS
4x4' TEE AT 3' FROM BASE
NORMAL POOL OUTLET ORNICE_-
GROUT EA(2I SbE
4' DIP JOIN
( I T SE LLM WITH A-LACK NEOPRENE
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RISER & DRAWDOWN DEVICE DETAIL
NTS

FES #10
Q-3.BCFS
DLA - 12' RCP 'R
L EVEL SPREADER SPECIFICATIONS 399.90
LENGTH - 50 FEET
0.5 FEET
VADTH o ENTRANCE - 10 MH 10A
FEET
GRASS TYPE - TALL FESCUE
LINER - DOUBLE NET FES 10
COCONUT FOR EROSION
CONTROL RA XU (NORTH
AMERICAN GREEN C350)
12' RCP
UPSTREAM INV 399.70
DOWNSTREAM INV 399.50 l
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50'
0
0
LEVEL SPREADER DETAIL
1' - 20'

. CLASS 1 RIP-RAP O 22' THICK AS SHOWN
USE FILTER FABRIC UNDERLINER (TYP)

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2' RCP I I
UP V 40200
DOWNSTREAM NV 399.90 I
i
RISER I I

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LINE SPILLWAY WITH CLASS 1 RIP-RAP
O 2Y THICK AS SHOWN
INSTALL DOUBLE NET COCONUT FIBER
EROSION CONTROL BLANKET (NORTH
AMERICAN GREEN C350) OR EQUIVALENT MH 10A
FES 10
BMP #1 -WET POND
SCALE 1' - 6O' ,

BOX RISER
WATER LEVEL OUR IN St 11' MK fAEE"m w OF DAM
TRASH L
PENT ROW ATIB M" POOL
MMIAJM SLOPE 3 : 1
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DOWA70R PAD
NAT-Fl.OATATI01/ DEVICE M RAP
ANTI-SEEP COLLAR
RCP OUTLET PIPE
CROSS SECTION

DIMENSIONS ELEV.
NORMAL POOL 29.055 SF 407.50 NOTES:
TOP OF DAM WIDTH lo' 411.50
Am-SEEP COLLAR 30 r - 1) FINAL SEEDING FOR INTERNAL SURFACES OF WET POND SHALL BE A
1 -YEAR STORM ORIFICE 3' 407.50 MIXTURE OF PANICUM CLANDESTINUM (DEER TONGUE) AND PENNISETUM
CONSERVATION POOL OwFICE 4 2Sca' 409.50 GLAUCUM (PEARL MILLET). SEEDING RATES SHALL SHALL BE AS
ounET PIPE INVERT M1 12' RCP 402.00 RECOMMENDED BY SUPPLIER.
oURET PWE RLVO1f our 12' RCP 399.70 2) FOR DETAILED STORM DRAINAGE INFORMATION SEE STORM DRAINAGE DESIGN
SPILLWAY 6S' LENGTH 410.50 CHART ON SHEEP 38

WET [dAl€TtAW DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
[Wetland maintenance wording is bracketed. Please modify the document as appropriate.]

The wet Fwelaandj-detention basin system is defined as the wet [wetlands detention basin, pretreatment
including forebays and the vegetated filter if one is provided.

Maintenance activities shall be performed as follows:

1. After every significant runoff producing rainfall event and at least monthly:
a. Inspect the wet [wre#tamJjdetention basin system for sediment accumulation, erosion, trash
accumulation, vegetated cover, and general condition.

b. Check and clear the orifice of any obstructions such that drawdown of the temporary pool occurs within
2 to 5 days as designed.

2. Repair eroded areas immediately, re-seed as necessary to maintain good vegetative cover, mow
vegetative cover to maintain a maximum height of six inches, and remove trash as needed.
3. Inspect and repair the collection system (i.e. catch basins, piping, swales, riprap, etc.) quarterly to
maintain proper functioning.

4. Remove accumulated sediment from the wet [Wetland] detention basin system semi-annually or when
depth is reduced to 75% of the original design depth (see diagram below). Removed sediment shall be
disposed of in an appropriate manner and shall be handled in a manner that will not adversely impact
water quality (i.e. stockpiling near a wet [we#lan* detention basin or stream, etc.).
The measuring device used to determine the sediment elevation shall be such that it will give an accurate
depth reading and not readily penetrate into accumulated sediments.

When the permanent pool depth reads o a. 6 feet in the main pond, the sediment shall be removed.
[For stormwater wetlands: If the elevation of the marsh areas exceed the permanent pool elevation, the
sediment should be removed. to design levels. This shall be performed by removing the upper 6 inches. of
soil and stockpiling it. Then the marsh area shall be excavated six inches below design elevations.
Afterwards the stockpiled soil should be spread over the marsh surface. The soil should not be stockpiled
for more than two weeks.]
When the permanent pool depth reads 4o 8.6 feet in the forebay [and micro-pool], the sediment shall
be removed.

BASIN DIAGRAM
(fill in the blanks)
0 Permanent Pool Elevation 4°7• S

Sediment moval El. _4. 4,? 75%
4.1 Sediment Removal Elevation 4.o44.1 75%

Bottom E vation o3. 0 5% Bottom
,3.0 0
FOREBAY MAIN POND

Page 1 of 2

5. Remove cattails and other indigenous wetland plants when they cover 50% of the basin surface. These
plants shall be encouraged to grow along the vegetated shelf and forebay berm.

[For wetlands: Wetland planting densities in the marsh areas should be maintained by replanting bare
areas as. needed. Wetland plants should be encouraged to grow in the marsh areas.]

6. If the basin must be drained for an emergency or to perform maintenance, the flushing of sediment
through the emergency drain shall be minimized to the maximum extent practical.
7. All components of the wet foe0and detention basin system shall be maintained in good working order.

8. Level spreaders or other structures that provide diffuse flow shall be maintained every six months. All
accumulated sediment and debris shall be removed from the structure, and a level elevation shall be
maintained across the entire flow spreading structure. Any down gradient erosion must be repaired and/or
replanted as necessary.
I acknowledge and agree by my signature below that I am responsible for the performance of the seven
maintenance procedures listed above. I agree to notify DWQ of any problems with the system or prior to any
changes to the system or responsible party.

Print name: yoNhT'~iRN S1~1NN~ye-
Title: &1V4,6?smr.NT VXANaM.

Address: 72-01 -11,irnAe_ 5k.,n~.s Sv+ie. NLWj!~v+ ~234b~
Phone: TS `7 - 2~(I --Z()
~-7
Signature:
Date: 41- 0,

Note: The legally responsible party should not be a homeowners association unless more than 50% of the
lots have been. sold and a resident of the subdivision has been named. the president.
I, A.D. B ra d ~p r cA , a Notary Public for the State of No r ~h Cox o l; n oq

County of wQ-Ve, , do hereby certify that So n aA 1ar1 S Vi non u-
personally appeared before me this g-V~ day of '20OLI, and acknowledge the due
execution of the forgoing wet [wetland] detention basin maintenance requirements. Witness my hand and

official seal,

A- 0.
e

o

N.C.

SEAL

My commission expires JL) I~t 2 2.D

Page 2 of 2

DWQ Project No.

DIVISION OF WATER QUALITY - LEVEL SPREADER WORKSHEET

1. PROJECT INFORMATION (please complete the following information):
Project Name : r+ + u. R o a t- A +c E
Contact Person: w A, f a a. .-I E A Phone Number: ( 9 9) 4 6 9- 3 3 4 0
Level Spreader ID: .
Level Spreader Length r~ o ft. (perpendicular to flow)
Drainage Area z6. ac. (on-site and off-site drainage to the level spreader)
Impervious Area + 0. o ac. (on-site and off-site drainage to the level spreader)
Maximum Filter Strip/Buffer Slope 4 % (6% for forested, leaf littler cover, 8%a for thick ground cover)*
grass
Max. Discharge from a 10 Year Storm '56 cfs
Max. Discharge to Level Spreader 3.6 cfs
Filter Strip/Buffer Vegetation a r- A s S (thick ground cover or grass, canopied forest with leaf litter
groundcover)
Pre-treatment or Bypass Method N"e x R* a

11. REQUIRED ITEMS CHECKLIST

Initial in the space provided to indicate the following design requirements have been met and supporting documentation is attached. If a
requirement has not been met, attach an explanation of why. At a minimum, a complete stormwater management plan submittal includes
a worksheet for each BMP, design calculations, plans and specifications showing all BMPs and outlet structure details, a detailed
drainage plan and a fully executed operation and maintenance agreement. An incomplete submittal package will result in a request for
additional information and will substantially delay final review and approval of the project.
Applicants Initials
wt>g Level spreader is at least 13 ft. per cfs for thick ground cover or grass or 100 ft per cfs in canopied forest with leaf
litter.
,J o Pre-Form Scour Holes are on flat slopes only
No structures are located in protected buffers*
If bypass method specified in the Draft Level Spreader Design Option Document:
wi Bypass method is specified (if applicable) and plan details and calculations are provided
w n ?-1 Discharge to level spreader and subsequent filter strip is hydraulically and spatially separate from the bypass
1 discharge.
No structures are located in protected buffers.
Plan details for the bypass and outlets are provided.
The operation and maintenance agreement includes annual erosion and vegetation repair.
164 t2 e, The operation and maintenance agreement signed and notarized by the responsible party is provided.
* Level spreaders in series can be used on slopes of up to 15% in forested areas with leaf littler cover or on slopes of up to 25% in areas
with thick ground cover or grass if designed according to the Draft Level Spreader Design Option Document. This potentially requires a
minor variance in protected buffer areas. In any event the second level spreader cannot be located in Zone 1 of a protected buffer area.

Project No. DWQ (to be provided by DWQ)

DIVISION OF WATER QUALITY - 401 WET DETENTION BASIN WORKSHEET
DWQ Stormwater Management Plan Review:

1. PROJECT INFORMATION (please complete the following information):
Project Name : H I R Q o R L_ A IK C
Contact Person: ,-,A -:r E SL 14 6 AT Phone Number: (4 1 1 ) 4~ g . 33 4• o
For projects with multiple basins, sp cify which basin this worksheet applies to: J / A
Basin Bottom Elevation 40g, o ft. (average elevation of the floor of the basin)
Permanent Pool Elevation 40 S ft. (elevation of the orifice invert out)
Temporary Pool Elevation _4 0 9.5 ft. (elevation of the outlet structure invert in)
Permanent Pool Surface Area 2q, o S s sq. ft. (water surface area at permanent pool elevation)
Drainage Area 2 6. C; ac. (on-site and off-site drainage to the basin)
Impervious Area 1 0. 0 ac. (on-site and off-site drainage to the basin)
Permanent Pool Volume 84, 6 G 7> cu. ft. (combined volume of main basin and forebay)
Temporary Pool Volume 93, 2 4 Z cu. ft. (volume detained on top of the permanent pool)
Forebay Volume 41, 2-7 h cu. ft.

SA/DA used 2.06 (surface area to drainage area ratio)
Diameter of Orifice 3 in. (draw down orifice diameter)
II. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual. Initial in the space
provided to indicate the following design requirements have been met and supporting documentation is attached. If a requirement has
not been met, attach an explanation of why. At a minimum, a complete stormwater management plan submittal includes a worksheet for
each BMP, design calculations, plans and specifications showing all BMPs and outlet structure details, a detailed drainage plan and a
fully executed operation and maintenance agreement. An incomplete submittal package will result in a request for additional information
and will substantially delay final review and approval of the project
Applicants Initials
w n The temporary pool controls runoff from the 1 inch storm event.
The basin length to width ratio is greater than 3:1.
%A.1 M The basin side slopes are no steeper than 3:1.
Mi A submerged and vegetated perimeter shelf at less than 6:1 is provided.
w n..~ Vegetation to the permanent pool elevation is specified.
An emergency drain is provided to drain the basin.
The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet).
The temporary pool draws down in 2 to 5 days.
The forebay volume is approximately equal to 20% of the total basin volume.
Sediment storage is provided in the permanent pool.
Access is provided for maintenance.
A notarized site specific operation and maintenance (00) plan is provided.
V'& InJ A vegetation management/mowing schedule is provided in the 0&M plan.
Semi-annual inspections are specified in the 0&M plan.
A debris check is specified in the 0&M plan to be performed after every storm event.
A specific sediment clean-out benchmark is listed (elevation or depth) in 0&M plan.
w D...I A responsible party is designated in the 0&M plan.

1
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eW o. Figure 1- USGS Map
8666.l
Watts Chapel Soil & Environmental Consultants, PA
Project Mgr.: Withers & Ravenel 11010 Raven Ridge Rd.- Raleigh, NC 27614
SC [phone] - [phone]
Wake County, NC Web Page: www.SandEC.com
Scale:
1" = 2,000'
04/08/04 Raleigh West &
1 ake Wheeler Quadrangles

'pr

•s

t Y+ L..
•k,2 -
As 6 id

Ariz.

AS62:

i N

Ci.

ProjectM Scale:
8666.W1 1•=1320'
Project Date: Figure 2 - Soil Survey Soil & Environmental Consultants, PA
Mgr.: SC 4/9/04 Watts Chapel 11010 Raven Ridge Rd.- Raleigh, NC 27614
Withers & Ravenel [phone] • [phone]
Raleigh, North Carolina Web Page: www.SandEC.com
Wake County Soil Survey
Sheet 68

NORTH CAROLINA ECOSYSTEM ENHANCEMENT PROGRAM
IN LIEU FEE REQUEST FORM

Complete this form, print and sign, and either mail to NCEEP, 1619 Mail Service Center, Raleigh, NC
27699-1619, or fax to 919-733-5321. Attachments are acceptable to clarify information on the form.
1. Name of Applicant or Agent * Jonathon Skinner I.
10~ ~ t r?. ct' "
2. Name of Business * The Villages of Swift Creek LLC
3. Street Address * 729 Thimble Shoals Boulevard, Suite 6c

4. City, State, Zip * Newport News, VA 23606

5. Telephone * [phone]
6. Fax [phone]

7. E-mail NA
8. Project Name * Mirror Lake Subdivision

9. Project Location * Raleigh, Wake County, North Carolina

10. Lat-Long Coordinates 35.7463152 N, 78.0910014E
11. River Basin * Neuse

12. Cataloging Unit ("Igit) * 3 p~ o a o I
13. Project County * Wake

14. Riparian Wetland Impact * 0.5 acres
15. Non-Riparian Wetland Impact * NA acres

16. Coastal Marsh Impact * NA acres

17. Stream-Cold Impact * NA feet
18. Stream-Cool Impact * NA feet

19. Stream Warm Impact * NA feet
20. Buffer-Zone 1 impact * NA square feet

21. Buffer Zone 2 Impact * NA square feet

22. Buffer-Total (Zone 1 + Zone 2) * NA square feet
Date: Signature of Applicant or Agent:

Ft/
Attachments?
Yes E:]No
* Required information; zero answers in 14-22 should be indicated with "0° or "N/A", not left blank.
Buffer mitigation applicable only in the Neuse, Tar-Pamlico and Catawba River Basins
and the Randleman Lake Water Supply Watershed.
Go to EPA "Surf Your Watershed" http://cfoub.ega.gov/surf/locate/index.dm for CU determination
Direct all questions to Carol Shaw at 919-733-5205 or carol.show(c)-ncmail.net

Wetland Delineation Performed By: Soil & Environmental Consultants, PA
11010 Raven Ridge Road
Raleigh, North Carolina 27614
[phone]
DATA FORM
ROUTINE WETLAND DETERMINATION
(1987 COE Wetlands Delineation Manual)
Project/Site: Watts Chapel / 8666.W2 Date: April 14, 2004
Applicant/Owner: Swift Creek LLC County: Wake
Investigator: James Dasher / Aaron Cooper State: North Carolina

Do Normal Circumstances exist on the site? X Yes No Community ID: Mixed pine /hardwood
Is the site significantly disturbed (Atypical Situation)? Yes X No Transect ID: _Flag 125
Is the area a potential Problem Area? Yes X No Plot ID:
If needed, explain on reverse.) I
VEGETATION

Dominant Plant Species Stratum Indicator Dominant Plant Species Stratum Indicator
1. Pinus taeda Tree FAC 9.
2. Liquidambar styraciflua Tree FAC+ 10.
3. Acer rubrum Tree FAC 11.
4. Prunus serotina Tree FACU 12.
5. Eulalia vlminea Herb FAC+ 13.
6. Lonicera japonica Herb FAC- 14.
7. Ligustrum sinense Shrub FAC 15.
8. 16.
Percent of Dominant Species that are OBL, FACW, or FAC
(excluding FAC-): 71%
Remarks: Wetland Vegetation present.

HYDROLOGY

_ Recorded Data (Describe in Remarks): Wetland Hydrology Indicators:
_ Stream, Lake or Tide Gauge Primary Indicators:
_ Aerial Photographs _ Inundated
_ Other _ Saturated in Upper 12 Inches
X No Recorded Data Available _ Sediment Deposits
X Drainage Patterns in Wetlands
Field Observations: Secondary Indicators (2 or more required):
_ Oxidized Root Channels in Upper 12 Inches
Depth of Surface Water. NA (in.) _ Water-Stained Leaves
_ Local Soil Survey Data
Depth to Free Water in Pit: >12 (in.) _ FAC-Neutral Test
_ Other (Explain in Remarks)
Depth to Saturated Soil: >12 (in.)
Remarks: Wetland Hydrology Present

Wetland Delineation Performed By: Soil & Environmental Consultants, PA
11010 Raven Ridge Road
Raleigh, North Carolina 27614
[phone]

Project/Site: Swift Creek LLC / 8666.W2 Plot ID: Flag 125 - Upland

SOILS
Map Unit Name Drainage Class: Well-drained
(Series and Phase): ~A pling fine sandy loam Field Observations
Taxonomy (Subgroup): _ Typic Hapludult Confirm Mapped Type? Yes _ No

Profile Description:
Depth Matrix Color Mottle Color Mottle Texture, Concretions,
inches Horizon (Munsell Moist) _ (Munsell Moist) Abundance/Contrast Structure, etc.
0-4" A 10YR3/3 sand loam
4-12 B 2.5YR 5/3 sand loam

Hydric Soil Indicators:
Histosol Concretions
Histic Epipedon High Organic Content in Surface Layer in Sandy Soils
Sulfidic Odor Organic Streaking in Sandy Soils
Aquic Moisture Regime Listed on Local Hydric Soils List
Reducing Conditions Listed on National Hydric Soils List
Gleyed or Low-Chroma Colors Other (Explain in Remarks)
Remarks: Hydric Soil Absent

WETLANDS DETERMINATION

Hydrophytic Vegetation Present? X Yes _ No Is this sampling point within a wetland?
Wetland Hydrology Present? X Yes _ No Yes x No

Hydric Soils Present? Yes x No

Remarks:

Wetland Delineation Performed By: Soil & Environmental Consultants, PA
11010 Raven Ridge Road
Raleigh, North Carolina 27614
[phone]
DATA FORM
ROUTINE WETLAND DETERMINATION
(1987 COE Wetlands Delineation Manual)

Project/Site: Wafts Chapel / 8666.W2 Date: _ April 14, 2004
Applicant/Owner: Swift Creek LLC County: Wake
Investigator: James Dasher/ Aaron Cooper State: North Carolina

Do Normal Circumstances exist on the site? X Yes No Community ID: Headwater/Emergent
Is the site significantly disturbed (Atypical Situation)? Yes X No Transect ID: Flag 125
Is the area a potential Problem Area? Yes X No Plot ID:
If needed, explain on reverse.
VEGETATION

Dominant Plant Species Stratum Indicator Dominant Plant Species Stratum Indicator
1. Pinus taeda Tree FAC 9.
Lipuidambar styracif/ua Tree FAC+ 10.
3. Acer rubrum Tree FAC 11.
4. Rosa multiflora Shrub UPL 12.
5. Eulalia viminea Herb FAC+ 13.
6. Lonicera japonica Herb FAC- 14.
7. Juncus effusus Herb FACW+ 15.
8. 16.
Percent of Dominant Species that are OBL, FACW, or FAC
(excluding FAC-): 71%
Remarks: Wetland Vegetation present.

HYDROLOGY

Recorded Data (Describe in Remarks): Wetland Hydrology Indicators:
Stream, Lake or Tide Gauge Primary Indicators:
_ Aerial Photographs _ Inundated
_ Other X Saturated in Upper 12 Inches
X No Recorded Data Available Sediment Deposits
X Drainage Patterns in Wetlands
Field Observations: Secondary Indicators (2 or more required):
X Oxidized Root Channels in Upper 12 Inches
Depth of Surface Water. 0 (in.) X Water-Stained Leaves
_ Local Soil Survey Data
Depth to Free Water in Pit: 10 (in.) _ FAC-Neutral Test
Other (Explain in Remarks)
Depth to Saturated Soil: 1 (in.)
Remarks: Wetland Hydrology Present

a

h Wetland Delineation Performed By: Soil & Environmental Consultants, PA
11010 Raven Ridge Road
Raleigh, North Carolina 27614
[phone]

Project/Site: Swift Creek LLC / 8666.W2 Plot ID: Flag 125 - Wetland

SOILS
Map Unit Name Drainage Class: Somewhat poorly
(Series and Phase): Colfax sandy loam Field Observations.
Taxonomy (Subgroup): Aquic Fragiudult Conf.mt Mapped Type? Yes _ No

Profile Description:
Depth Matrix Color Mottle Color Mottle Texture, Concretions,
inches Horizon (Munsell Moist) (Munsell Moist) Abundance/Contrast Structure etc.
5-12" B 10YR5/2 5YR5/8 sand clay loam
0-5° A 10YR4/1 sandy clay loam

Hydric Soil Indicators:
Histosol Concretions
Histic Epipedon High Organic Content in Surface Layer in Sandy Soils
Sulfidic Odor Organic Streaking in Sandy Soils
Aquic Moisture Regime Listed on Local Hydric Soils List
X Reducing Conditions Listed on National Hydric Soils List
X Gleyed or Low Chroma Colors Other (Explain in Remarks)
Remarks: Hydric Soil Present

WETLANDS DETERMINATION

Hydrophytic Vegetation Present? X Yes _ No Is this sampling point within a wetland?
Wetland Hydrology Present? X Yes _ No X Yes No

Hydric Soils Present? X Yes _ No

Remarks:

WITHERS RAVE EL

STORMWATER MANAGEMENT PLAN

MIRROR LAKE
ATLANTIC HOMES - TRYON RD

Raleigh, North Carolina

Prepared For:
Atlantic Homes
s0 San Jose Dr, Suite 4C
Newport News, VA 236o6

Prepared By:
WITHERS & RAVENEL, INC
111 MacKenan Drive
Cary, North Carolina 27511

17
September 2004
Resubmitted October 2004
W&R Project No. 203209

,A4~i1 a%E G yiy Ry tf~r
, 1, iaL~ P~, B.v
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?so ~ , ~ Nt~;S6~e

William E. Lee, P.E.

INTRODUCTION
The purpose of this study is to document pre- and post-development peak stormwater discharges
for the 2-year design storm events. The goal is to provide detention structures adequate to maintain
a discharge less than or equal to the pre-development peak discharges after the site has been
developed.

The ± 26 acre site and surrounding drainage area are primarily open space and woods, and contains
a majority of B soils, with small areas of C soils. There is one stormwater Best Management Practice
(BMP) proposed forthe site to meet peak attenuation requirements and provide reductions of 85%
Total Suspended Solids (TSS) and 25% Total Nitrogen (TN).
The site has an existing pond which is not considered as part of this stormwater management plan
and was not used to determine peak attenuation in this study. There is an earth weir spillway at
normal pool level and it was assumed that the flow coming into the pond equals the flow exiting the
pond.

METHODOLOGY
The stormwater study was conducted using the natural drainage features as depicted by the City of
Raleigh aerial topographic information (2-ft contours), field survey data, and proposed development
within the drainage areas. The site was entered into the model as four drainage areas based on
natural drainage patterns, to evaluate pre development peak discharge rates. In the proposed
model, the area was subdivided with two areas routed through the BMP and the remaining area
discharging directlyto the outfall. The individual peak discharge rates from the two evaluation
points were summed to get total pre- and post-development peak discharge.

The scope of work included the following analyses:
Hydrology
? Simulation of the 2-year and ioo-year rainfall events for the Raleigh area
? Formulation of the 2-year and loo-year flood hydrographs for the pre- and post-
development drainage areas
Hydraulic
? Routing the 2-year and loo-year flood hydrographs for post development runoff through
the proposed stormwater BMP
The 2-year design storm is studied to satisfy the City of Raleigh Ordinance Sec. 10-9023. The ioo-
year design storm is routed through the emergency spillway of the proposed wet pond, and is
included in this study for that purpose. The results of the hydrology calculations are used in the
hydraulic analyses. The hydraulic design requires the development of stage-storage and stage-
discharge functions for the wet pond. The rainfall/runoff hydrographs, stage-storage and stage-
discharge functions have been compiled to create a routing computer simulation model using
Haestad Methods PondPack v9.o software. This PondPack model was then used to assess the
impact of the peak discharges for the design rainfall events. The PondPack modeling results are
provided as appendixto this report.

HYDROLOGY
The SCS Method was used to develop runoff hydrographs for the Type II, 24-hour duration, 2-year
and loo-year storm events for the Raleigh area. This method requires three basic parameters: a

Atlantic Homes - Tryon Rd 1 W&R Project 203209
Stormwater Management Report September 2004

curve number (CN), time of concentration (t), and drainage area. The rainfall data used in this
design was taken from the Intensity-Duration-Frequency Table for the Triangle area published in the
City of Raleigh Stormwater Management Design Manual

Curve numbers were based on soil type and land use. Soil types were delineated from the Soil
Survey of Wake County, North Carolina (November 1970). Land use for existing conditions was based
on the most recent Wake County aerial photographs. Post development land use is residential
based on the proposed site plan. The curve numbers used in this study are listed in Table 1.
Times of concentration were calculated using methods described in the SCS publication "Urban
Hydrology for Small Watersheds, TR-55" and based on Wake County topographic maps and field
survey data. The post-development time of concentration was calculated for the two drainage areas
that are piped to the wet pond based on the flow time through the piped drainage systems and
small areas of sheet flow. The breakdown of the time of concentrations and the calculated values
are found in the appendices of this report. The time of concentration paths are shown on the
drainage area maps also found in the appendix.

The pre-development model includes four drainage areas. Basin #1, Basin #2, and Basin #3 are
analyzed at Outfall #1. These basins are delineated based on natural drainage patterns and include
on-site and off-site area in order to analyze the effects of the runoff from the site. Basin #1 is 78.75
acres and includes the drainage area for the existing farm pond. Basin #2 is 32.82 acres and
includes the area downstream of the pond and that area draining to about 500 feet downstream of
the Gorman Street extension. Basin #3, 31.73 acres, extends to Outfall #1. Basin #4 contains 1.30
acres and is analyzed at Outfall #2. This basin only includes on-site area.
The post-development model includes the same area as the pre-development model, but is divided
into eight drainage areas based on the proposed development. These drainage areas are delineated
from the proposed grading plans for post development conditions. Basin #1, Basin #2A, Basin #2B,
DA #i to Wet Pond, DA #2 to Wet Pond, DA #3 to Wet Pond, and Basin #3 are analyzed at Outfall #i.
Basin #1 is reduced from the pre-development model to 66.91 acres due to site grading, but still
includes the area draining to the farm pond. Basins 2A and 2B, 3.4 acres and 15.76 acres, contain
the area downstream of the pond that is naturally draining to about 500 feet downstream of the
Gorman Street extension. DA#1, 13.06 acres, and DA #3, 9.86 acres, include on-site and off-site
area that drains into the piped drainage systems that outfall in the proposed wet pond. DA #2, 3.61
acres, is the area that naturally drains into the wet pond. Basin #3 is 31.49 acres includes the
natural runoff to Outfall #1. Basin #4 contains 0.45 acres and is analyzed at Outfall #2. Drainage
area delineation maps, as well as a summary of data used to formulate hydrographs and peak
discharges are included in the appendix of this report.

Atlantic Homes - Tryon Rd 2 W&R Project 203209
Stormwater Management Report September 2004

TABLE 1. DRAINAGE AREA SUMMARY

Pre-Development

Pre-development
Basin #i

Description Acres . Soil Type Curve Number
Open Space 36.21 B 61
Open Space 0.54 C 74

Woods 28.o6 B 55
Woods 7.315 C 70

Impervious 6.63 - 98

Total 78.75 63

Pre-development
Basin #2

Description Acres Soil Type Curve Number
Open Space 10.27 B 61
Woods 16.20 B 55

Woods 3.05 C 70
Impervious 3-29 - 98
MMWM

Total 32.82 63

Pre-development
Basin #
Description Acres Soil Type Curve Number

Open Space 14.65 6 61
Woods 14.65 B 55
Woods 2.43 C 70

Total 31.73 59'

Atlantic Homes - Tryon Rd 3 W&R Project 203209
Stormwater Management Report September 2004

Pre-development
Basin #
Desc;Space n Acres Soil Type Curve Number
Open 1.30 B 61

T1.30 61

Post Development

Post-development
Basin #1
Description Acres Soil Type Curve Number
Open Space 27.04 B 61

Open Space 0.54 C 74
Woods 24.77 B 55
Woods 7.32 C 70

Lots -1/8 Acre 1.30 B 85
Right of Way 0.29 B 89

Impervious 5.65 - 98

Total 66.91 64

Post-development
Basin #2A
Description Acres Soil Type Curve Number
Open Space o.62 B 61
Woods o.68 $ 55

Woods 0.87 C 70
Lots -1/8 Acre o.69 B 85

Lots -1/8 Acre 0.30 C 9o
Impervious 0.25 - 98

Total 3.40 72

Atlantic Homes - Tryon Rd 4 W&R Project 203209
Stormwater Management Report September 2004

Post-development
Basin #2B
Description Acres Soil Type Curve Number
Open Space 6.83 B 61
Woods 4.12 B 55

Woods 1.37 C 70
Impervious 3.45 98

Total 15.76 68

Post-development
Basin #
Description Acres Soil Type Curve Number

Open Space 14.44 B 61
Woods 14.65 B 55

Woods 2.40 C 70

Total 31.49 59

Post-development
Basin #
Description Acres Soil Type Curve Number
Open Space 0.12 B 61
Lots -1/8 Acre 0.33 B 85

Total 0.45 78

Post-development
DA #1 to Wet Pond

[Description Acres Soil Type Curve Number
ce 5.99 B 61
us 6.24 B 98

ay 0.82 B 8g

13.06 80

Atlantic Homes - Tryon Rd 5 W&R Project 203209
Stormwater Management Report September2004

Post-development
DA #2 to Wet Pond
Description Acres Soil Type Curve Number
Open Space 2.75 B 61

Impervious 0.31 B 98
Woods 0.55 B 55

Total 3.61 63

Post-development
DA # to Wet Pond
Description Acres Soil Type Curve Number
Open Space 1.27 B 61

Lots - i/8 Acre 4.8o B 85
Lots - i/8 Acre 0.07 C 9o

Right of Way 3.72 B 89

Total 9.86 83

HYDRAULICS
Computer simulated reservoir routing of the 2-year and loo-year design storms utilized stage-
storage and stage-discharge functions. Stage-storage functions were derived from the proposed
contours for the wet pond. A non-linear regression relation for surface area versus elevation was
derived for the BMP. This relation estimates the incremental volume of the basin to the stage or
elevation of the basin. Stage-discharge functions were developed to size the outlet structure for the
pond.

CONCLUSIONS
Based on the routing study, the post development peak discharge from the entire site is less than
the pre-development peak for the 2-year design storm. Table 2 below summarizes the peak
attenuation results. The pond routes the loo-year design storm through an emergency spillway. The
design summary of the proposed pond can be found under "Post Development Calculations" in the
appendix.

The resulting post development nitrogen export is 4.63 lbs/ac/yr for the site. A buy-down of $8,722
is required to reach 3.6 lbs/ac/yr. Copies of the detailed supporting calculations for nitrogen export
are provided in the "Nitrogen Calculation" section of the appendix to this report.

Atlantic Homes - Tryon Rd 6 W&R Project 203209
Stormwater Management Report September 2004

TABLE 2. PEAK ATTENUATION SUMMARY FOR THE 2-YEAR DESIGN STORM
2-year ,,,k

Pre-development
Outfall #1 53.09 cfs

Outfatl #2 o.8o cfs
Pre-Development Total 53.89 cfs

Post-Development

Otitfall #1 49.95 cfs
Outfatl #2 0.73 cfs
Post-Development Totat 50.68 cfs

Atlantic Homes - Tryon Rd 7 W&R Project 203209
Stormwater Management Report September 2004

APPENDIX

Atlantic Homes - Tryon Rd 8 W&R Project 203209
Stormwater Management Report September 2004

i

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Type

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BY Da goer
5w7 7•,0 PRE DEVELOPMENT WITHERS RAVENEL Shee1Na.
Drawn By Date HOMES - TRYON ROAD E"°'"EE"5 . P`"""E"S I suRVerDrts
5a~ 9/41n04 ATLANTIC DRAINAGE AREA LAYOUT 111 MacKenan Drive Cary, North Carolina 27511
Checked By lob No, tel:[phone] www.wAhersravenel.com fare 919-467.6009
WEL 707209.0

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o~ .,tttli~ ~•r J~ 1 r~ t tie € { , { `Vi' e Er t Y'((~' ~"~f` ~((r /
! ~ i' ~ ` ~..•..\'`J.."?-.?/` ~ !JJ ,~j t w ~r'r f ~i: ~!ti~J ° t+'r
~~.;:1 t ,f1 ~t t!~ t1l'* f I ~ #1: /'f ~t rr , ;1 t--...~.. ~.;i h t, f^• - i~~ .
i4.......-.,`~; i `l / J 1 :!C`~ ~ r ~0 . m ' ~ fa: 6.91 C ! e i v (
~,._f `'''~;/r, i' ? •1., '`l..~Y..i ! ' i 1~~ S D 1
,f J~ J Ew r~4 1 4. f , y V ' \ i1~~` i k:i
r f I . t t Drain, ~t.~y{
Q7,/ lit
f /tt_ rG 4 ~ti `~t~ (s/'''U J F 'i~( t` f ! t1 t
,~r r~~ ; ~ ~ t~.,,_,„......!•t \ ~ `t ~x; ~ ~ ti.""1,Jtt ! i i;r~ Ir,i f ~ f'.-^-., r € J 1~~~`"t
r l 1 W
~ ti ~ ~ } r...! S ti t,' i t.t;,...".-..__.,,,.._-.^,.1;t t J
D
.4 , 7-v+ftl,
' 1 •r li f f~ f J ?
1 It I 1 } ;f/41 f`~ f~ » z•y'~ - y t~\ M. 1 t z }j1iB 1 i.
n y
j ~ ~!i S 1 f l f
i is ljj~
li Sir /`4i -'s'.~^'«^^'ti-.._ ...,,;:1~- i,,^.~.~ `~~'h. r" !
t v r 1
-----"-~t.r• ~ ',~,-r' r.`~.-,~~, '~`~.l'- ,..N~
4 }r / f ~ r.r•'~~ `e ~i f i \ U 1 ~ ~ ~ ` t E - " ~ = f/ ~P""f
BKainage. rea - 45 Acres
1fJ1~' /I~._!-".t` "~x ~ ~~l'~?~~..,,~,,.~ ~ ~ \ ~i J ~ 1. I i ~Zii J` '4~\ 1'~ ; 3'`i~ - M.,.-r

` THAI I: # r J` { rj''r~ ''r~` UTFALL #1
jy }#,`t't : ._/~r "~»=j ~t,t~ f r l t r \ r~1 f( 1(' f! `
tt t lf` fir, f f,? tr r - "ti-
~E t f-.~ 4 ~ / r %('jj !Ir .,1~,~,'µ„r-..---..,._::~•, ~ t ,Ya
3 to
Area. 96 c s I'r , ! ` " f t`~\
jil"
~ \Y J f ~J r7J7 ~ 7 J ~ 7: ~ y l ~ ~ ~ `"..~~Y f ~ l f ! ` ' r, i ' ~
Time of Concentration
1 ii 1 ~i { ` ,~`f~ ?lr ,l li (f ! t f 1 J ~"'~t i j~ t t f i~.""`--""``"y. r«"y `-,1
Type
r +(`t~t i, t/1 y. ^ G j t Channel Flow
~I, , I f ; i 1, i~,'` l "l~~ J/!' ~jj ~ ~ r; ~ ~4 ~rl ~ ~ ~s, ~..-:...,f'. r i I I I f l r~~ ....r,,..,„,~ ~ t, ~..t`'•.~ , ~
Vi%
Shallow Flow
` i' = ti ~I ~ //f r r : r' ! f tt t tf.,~ f,.~ . ~ ~ ~ 1 ( f~ ` it { f ~ ~ l ' ~ ` l~ ~ ~ ~ 4 °%,ti
J. + 1 !t' r r t i; V l i l~ r?( 1 J. i! f 1? t i i Shallow Flow Paved
jr r~ ~s f'kl ! 1i i1 Sheet Flow
i 77M. 1 I i O,. J'f ,,._.f t#~, ~if ~1 r 1 1~ f i r,! 1\ ` # ((1 ,/r > J t. i ~4ti ` T r~ ( i /J r r 1
BY Designer WITHERS ` Y E N E L Sheet No.
sAH = ,ea POST DEVELOPMENT
Drawn By SAN Dace,en4ne04 ATLANTIC HOMES ' TRYON ROAD ENGINEERS I PLANNERS I SURVEYORS 2
DRAINAGE AREA LAYOUT ,,,htacKerenDrrveCary, North CardinaY76„
decked BY No. tek 919469-3340 www.withersravenel.wm fax [phone]
- job

n Project Name: Gorman-Tryon Project 203209
Ci at • Raleigh, NC te• 14-Oct-04
Table 1. l Surface Area to Drainage Area Ratio for Permanent Pool Sizing• for 85% Pollutant
Removal Efficiency in the Piedmont
% Impervious Permanent Pool Depth (feet)
Cover 3.0 4.0 5.0 6.0 7.0 8.0 9.0
10 0.59 0.49 0.43 0.35 0.31 0.29 0.26
20 0.97 0.79 0.70 0.59 0.51 0.46 0.44
30 1.34 1.08 0.97 0.83 0.70 0.64 0.62
40 1.73 1.43 1.25 1.05 0.90 0.82 0.77
50 2.06 1.73 1.50 1.30 1.09 1.00 0.92
60 2.40 2.03 1.71 1.51 1.29 1.18 1.10
70 2.88 2.40 2.07 1.79 1.54 1.35 1.26
80 3.36 2.78 2.38 2.10 1.86 1.60 1.42
90 3.74 3.10 2.66 2.34 2.11 1.83 1.67
Source: NCDENR/DWQ Stormwater Best Management Practices, pg. 5, April 1999
STORMWATER BMP #1 - WET POND (25% TN Removal)
Area % IA Imp. Area
Land Use (ac) (ac)
Open Space 10.005 0 0.0
Impervious 6.55 100 6.6
ROW 4.542 65 3.0
Lots 4.878 65 3.2
Woods 0.549 0 0.0
Totals 26.524 12.7
Total % Impervious Surface Area = 47.8 %
Normal Pool De 3 4 5 6 7 8 9
SA/DA Ratio 2.06 1.73 1.50 1.30 1.09 1.00 0.92
Minimum Surface Area R uired
Acres 0.55 0.46 0.40 0.34 0.29 0.27 0.24
Sq. Ft 23800.94 19988.17 17330.78 15020.01 12593.70 11553.85 10629.55
Surface Area of Permanent Pool:
Assumed depth = 3 feet
SA/DA ratio = 1.73 % From Table 1.1
Minimum pond surface area (SA) _ (DA * SA/DA ratio)/100
SA = 0.459 acres
19988 sq. ft.
Normal pool elevation = 407.5 feet
Surface area provided = 0.533 acres
23217 sq. ft.
1-Inch Runoff Volume Calculation
Using the runoff volume calculations in the "Simple Method" as described by Schueler (198
Rv = 0.05 + 0.009() where, Rv = Runoff coefficient, in./in.
= Percent impervious
Rv = 0.48 in./in.
Total runoff volume from 1-inch precipitation:
Runoff volume, S - (Design rainfall) (Rv) (Drainage Area)
S = 1.061 acre-ft
46217 cu. ft.
Water quality pool elevation= 409.50 feet
Storage volume provided - 1.169 acre-ft
50922 cu.ft.

PRE-DEVELOPMENT

CALCULATIONS

Atlantic Homes - Tryon Rd 9 W&R Project 203209
Stormwater Management Report September 2004

• 1

BASIN #1

0
Hi

BASIN #2 (;nk BASIN #4
4
CL
Jun 10
rn
0

BASIN #3 ~1nkg

Outfall #2
Jun 20
r

w

Outfall #1

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Job File: K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW
Rain Dir: K:\03\03-200\03209\H&H\

JOB TITLE

Project Date: 8/30/2004
Project Engineer: Withers and Ravenel
Project Title: Atlantic Homes - Tryon Rd
Project Comments:
This report documents the pre-development peak discharge rates and supporting calculations
for the site.

SIN: 22160372E1C5 Withers & Ravenel
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ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - PRE-DEVELOPMENT ti

Table of Contents i

Table of Contents

MASTER SUMMARY

Watershed....... Master Network Summary 1.01

DESIGN STORMS SUMMARY

Wake County..... Design Storms 2.01

TC CALCULATIONS

BASIN #1........ Tc Calcs 3.01
BASIN #2........ Tc Calcs 3.04

BASIN #3........ Tc Calcs 3.07
BASIN #4........ Tc Calcs 3.10

CN CALCULATIONS

BASIN #1........ Runoff CN-Area 4.01

BASIN #2........ Runoff CN-Area 4.02
BASIN #3........ Runoff CN-Area 4.03

BASIN #4........ Runoff CN-Area 4.04

SIN: 22160372E1C5 Withers & Ravenel
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ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Master Network Summary Page 1.01
Name.... Watershed
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW

MASTER DESIGN STORM SUMMARY

Network Storm Collection: Wake County

Total
Depth Rainfall
Return Event in Type RNF ID

1 3.0000 Synthetic Curve TypeII 24hr
2 3.6000 Synthetic Curve TypeII 24hr
5 4.6500 Synthetic Curve TypeII 24hr
10 5.3800 Synthetic Curve TypeII 24hr
25 6.4100 Synthetic Curve TypeII 24hr
50 7.2100 Synthetic Curve TypeII 24hr
100 8.1000 Synthetic Curve TypeII 24hr
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)

Max
Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage
Node ID Type Event ac-ft Trun hrs cfs ft ac-ft

BASIN #1 AREA 2 4.649 12.3284 30.44
BASIN #1 AREA 100 24.571 12.3284 202.98
BASIN #2 AREA 2 1.941 12.0785 22.21
BASIN #2 AREA 100 10.257 12.0785 141.04
BASIN #3 AREA 2 1.410 12.2451 10.58
BASIN #3 AREA 100 8.716 12.1618 95.00
BASIN #4 AREA 2 .067 12.0785 .80
BASIN #4 AREA 100 .381 12.0785 5.40
JUNC 10 JCT 2 6.589 12.1618 42.64
JUNC 10 JCT 100 34.829 12.1618 296.18
JUNC 20 JCT 2 7.999 12.1618 53.09
JUNC 20 JCT 100 43.544 12.1618 391.18

SIN: 22160372E1C5 Withers & Ravenel
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ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Master Network Summary Page 1.02
Name.... Watershed
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)

Max
Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage
Node ID Type Event ac-ft Trun hrs cfs ft ac-ft

*OUTFALL #1 JCT 2 7.999 12.1618 53.09
*OUTFALL #1 JCT 100 43.544 12.1618 391.18
*OUTFALL #2 JCT 2 .067 12.0785 .80
*OUTFALL #2 JCT 100 .381 12.0785 5.40

SIN: 22160372E1C5 Withers & Ravenel
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ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Design Storms Page 2.01
Name.... Wake County

File.... K:\03\03-200\03209\H&H\
Title... Project Date: 8/30/2004
Project Engineer: wr
. Project Title: Watershed
Project Comments:
DESIGN STORMS SUMMARY
Design Storm File,ID = Wake County
Storm Tag Name = 2

Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 2 yr
Total Rainfall'Depth= 3.6000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs
Storm Tag Name = 100
----------------------------------------------------------7-----------
Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 100 yr
Total Rainfall Depth= 8.1000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs

SIN: 22160372E1C5 Withers & Ravenel
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ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Tc Calcs Page 3.01
Name.... BASIN #1
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW

TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: TR-55 Sheet

Mannings n .2400
Hydraulic Length 97.55 ft
2yr, 24hr P 3.6000 in
Slope .020500 ft/ft
Avg.Velocity .12 ft/sec
Segment #1 Time: .2177 hrs

Segment #2: Tc: TR-55 Shallow
Hydraulic Length 2212.80 ft
Slope .016300 ft/ft
Unpaved
Avg.Velocity 2.06 ft/sec

Segment #2 Time: .2984 hrs

Segment #3: Tc: TR-55 Channel
Flow Area 4.0000 sq.ft
Wetted Perimeter 6.00 ft
Hydraulic Radius .67 ft
Slope .009800 ft/ft
Mannings n .0400
Hydraulic Length 1432.76 ft
Avg.Velocity 2.81 ft/sec
Segment #3 Time: .1414 hrs

Total Tc: .6575 hrs

S/N: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

! ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Tc Calcs Page 3.02
Name.... BASIN #1
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW

Tc Equations used...

SCS TR-55 Sheet Flow
Tc =.(.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))

Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, %
SCS TR-55 Shallow Concentrated Flow
Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)

Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 'Time: 3:44 PM Date: 10/14/2004

ATLAN'T'IC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Tc Calcs Page 3.03
Name.... BASIN #1
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW
SCS Channel Flow

R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n
Tc = (Lf / V) / (3600sec/hr)

Where: R = Hydraulic radius
Aq = Flow area, sq.ft.
Wp = Wetted perimeter, ft
V = Velocity, ft/sec
Sf = Slope, ft/ft
n = Mannings n
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Tc Calcs Page 3.04
Name.... BASIN #2

File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW

TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 87.63 ft
2yr, 24hr P 3.6000 in
Slope .022800 ft/ft
Avg.Velocity .13 ft/sec
Segment #1 Time: .1915 hrs

Segment #2: Tc: TR-55 Shallow
Hydraulic Length 515.50 ft
Slope .058200 ft/ft
Unpaved
Avg.Velocity 3.89 ft/sec
Segment #2 Time: .0368 hrs

Segment #3: Tc: TR-55 Channel
Flow Area 9.0000 sq.ft
Wetted Perimeter 9.00 ft
Hydraulic Radius 1.00 ft
Slope .012000 ft/ft
Mannings n .0400
Hydraulic Length 831.32 ft
Avg.Velocity 4.08 ft/sec
Segment #3 Time: .0566 hrs

Total Tc: .2848 hrs

SIN: 22160372E1C5 Withers & Ravenel
PondPack Vex. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Tc Calcs Page 3.05
Name.... BASIN #2
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW

Tc Equations used...
.

SCS TR-55 Sheet Flow

Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, %
SCS TR-55 Shallow Concentrated Flow

Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Tc Calcs Page 3.06
Name.... BASIN #2
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW

SCS Channel Flow
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n

Tc = (Lf / V) / (3600sec/hr)
Where: R = Hydraulic radius
Aq = Flow area, sq.ft.
Wp = Wetted perimeter, ft
V = Velocity, ft/sec
Sf = Slope, ft/ft
n = Mannings n
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT PRE-DEVELOPMENT

Type.... Tc Calcs Page 3.07
Name.... BASIN #3
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW

TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: TR-55 Sheet

Mannings n .2400
Hydraulic Length 111.50 ft
2yr, 24hr P 3.6000 in
Slope .017900 ft/ft
Avg.Velocity .12 ft/sec
Segment #1 Time: .2557 hrs

Segment #2: Tc: TR-55 Shallow

Hydraulic Length 1297.50 ft
Slope .047800 ft/ft
Unpaved
Avg.Velocity 3.53 ft/sec
Segment #2 Time: .1022 hrs

Segment #3: Tc: TR-55 Channel

Flow Area 9.0000 sq.ft
Wetted Perimeter 9.00 ft
Hydraulic Radius 1.00 ft
Slope .005950 ft/ft
Mannings n .0400
Hydraulic Length 672.72 ft
Avg.Velocity 2.87 ft/sec
Segment #3 Time: .0650 hrs

Total Tc: .4229 hrs

S/N: 22160372E1C5 Withers & Ravenel
.PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - PRE-DEVELOPMENT

Type.... Tc Calcs Page 3.08
Name.... BASIN #3

File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW

Tc Equations used...

SCS TR-55 Sheet Flow
Tc (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))

Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, %
SCS TR-55 Shallow Concentrated Flow
Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)

Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

TRYON
ATLANTIC HOMES - RD
PONDPACK OUTPUT - PRE-DEVELOPMENT
Type.... Tc Calcs Page 3.09
Name.... BASIN #3
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW

SCS Channel Flow
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n
Tc = (Lf / V) / (3600sec/hr)

Where: R = Hydraulic radius
Aq = Flow area, sq.ft.
Wp = Wetted perimeter, ft
V = Velocity, ft/sec
Sf = Slope, ft/ft
n = Mannings n
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 2216037 MC5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - PRE-DEVELOPMENT

Type.... Tc Calcs Page 3.10
Name.... BASIN #4

File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW
.
TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 94.87 ft
2yr, 24hr P 3.6000 in
Slope .021100 ft/ft
Avg.Velocity .13 ft/sec
Segment #1 Time: .2104 hrs

Segment #2: Tc: TR-55 Shallow
Hydraulic Length 190.90 ft
Slope .021000 ft/ft
Unpaved
Avg.Velocity 2.34 ft/sec
Segment #2 Time: .0227 hrs

Total Tc: .2331 hrs

S/N: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT i

Type.... Tc Calcs Page 3.11
Name.... BASIN #4
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW

Tc Equations used...

SCS TR-55 Sheet Flow

Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, %
SCS TR-55 Shallow Concentrated glow

Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282.* (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN.: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - PRE-DEVELOPMENT

Type.... Runoff CN-Area Page 4.01
Name.... BASIN #1

File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW
RUNOFF CURVE NUMBER DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C RUC CN

Impervious Areas - Paved parking to 98 6.628 98.00
Pasture, grassland - good; B 61 36.210 61.00
Pasture, grassland - good; C 74 .537 74.00
Woods - good; B 55 28.063 55.00
Woods - good 70 7.315 70.00
COMPOSITE AREA & WEIGHTED CN 78.753 62.90 (63)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Runoff CN-Area Page 4.02
Name.... BASIN #2
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW
RUNOFF CURVE NUMBER DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C RUC CN

Impervious Areas - Paved parking to 98 3.291 98.00
Pasture, grassland - good; B 61 10.274 61.00
Woods - good; B 55 16.199 55.00
Woods - good; C 70 3.051 70.00
COMPOSITE AREA & WEIGHTED CN 32.815 62.59 (63)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Runoff CN-Area Page 4.03
Name.... BASIN #3
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW

RUNOFF CURVE NUMBER DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C %UC CN

Pasture, grassland - good; B 61 14.648 61.00
Woods - good; B 55 14.648 55.00
Woods - good 70 2.434 70.00
COMPOSITE AREA & WEIGHTED CN 31.730 58.92 (59)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES TRYON RD
PONDPACK OUTPUT - PRE-DEVELOPMENT

Type.... Runoff CN-Area Page 4.04
Name.... BASIN #4
File.... K:\03\03-200\03209\H&H\GORMAN PRE NOPOND.PPW
RUNOFF CURVE NUMBER DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C %UC CN

Pasture, grassland, or range - good 61 1.300 61.00
COMPOSITE AREA & WEIGHTED CN 1.300 61.00 (61)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

POST DEVELOPMENT

CALCULATIONS

Atlantic Homes - Tryon Rd 10 W&R Project 203209
Stormwater Management Report September 2004

Basil 1
Basin 4

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Basin 2A
Go an
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Oudall
Addlink 80
Basin .E.

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- oaC:nK3~ DA 2
CA Roy<e Wet dlipk ii0
Basin 3 Addlink 90

Jun 20
D DA 3
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Outfall

ATLRNTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Job File: K:\03\03-200\03209\H&H\GORMAN_POST_NEWPOND.PPW
Rain Dir: K:\0.3\03-200\03209\H&H\

JOB TITLE

Project Date: 10/14/2004
Project Engineer: Withers and Ravenel
Project Title: Atlantic Homes - Tryon Rd
Project Comments:
This report documents the post-development peak discharge rates and supporting calculations.
DESIGN SM44MY
Pond #1 - Normal Pool = 407.5 ft
Bottom Elevation = 403.5 ft
Top of Dam = 411.5 ft
Required Surface Area = 0.459 Acres (19,988 ft2)
Surface Area Provided = 0.533 Acres (23,217 ft2)
Required WQ Storage Volume = 1.061 Acre-ft (46,217 ft3)
WQ Storage Volume Provided = 1.169 Acre-ft (50,922 ft3)
100-year Calculated Freeboard = 0.14 ft

Outlet Structure:
3 ft x 3 ft Inlet Box Riser with 1 ft x 0.5 ft opening on one side @ 409.5'ft
Orifice @ 407.5 ft - 3 in circular
12 in RCP Culvert
Emergency Spillway - 65 ft wide - Crest = 410.50 ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Table of Contents i

Table of Contents

MASTER SUMMARY

Watershed....... Master Network Summary 1.01

DESIGN STORMS SUMMARY

Wake County..... Design Storms 2.01

******************xt** TC CALCULATIONS

BASIN 1......... Tc Calcs 3.01

BASIN 2A........ Tc Calcs 3.04
BASIN 2B........ Tc Calcs 3.07

BASIN 3......... Tc Calcs 3.10
BASIN 4......... Tc Calcs 3.13
DA 1 WP......... Tc Calcs 3.15

DA 2 WP......... Tc Calcs 3.17
DA 3 WP......... Tc Calcs 3.19

CN CALCULATIONS

BASIN 1......... Runoff CN-Area 4.01
BASIN 2A........ Runoff CN-Area 4.02

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

i
ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Table of Contents ii

Table of Contents (continued)

BASIN 2B........ Runoff CN-Area 4.03

BASIN 3......... Runoff CN-Area 4.04
BASIN 4......... Runoff CN-Area 4.05

DA 1 WP......... Runoff CN-Area 4.06
DA 2 WP......... Runoff CN-Area 4.07

DA 3 WP......... Runoff CN-Area 4.08

POND VOLUMES

WET POND........ Vol: Elev-Area 5.01

OUTLET STRUCTURES

Wet Pond........ Outlet Input Data 6.01 .
Composite Rating Curve 6.05

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT
Type.... Master Network Summary Page 1.01
Name.... Watershed
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

MASTER DESIGN STORM SUMMARY

Network Storm Collection: Wake County

Total
Depth Rainfall
Return Event in Type RNF ID

2 3.6000 Synthetic Curve TypeII 24hr
100 8.1000 Synthetic Curve TypelI 24hr
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(True= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)

Max
Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage
Node ID Type Event ac-ft Trun hrs cfs ft ac-ft

BASIN 1 AREA 2 4.213 12.3284 28.45
BASIN 1 AREA 100 21.511 12.2451 178.35
BASIN 2A AREA 2 .336 12.0785 4.63
BASIN 2A AREA 100 1.355 12.0785 18.82
BASIN 2B AREA 2 1.261 12.0785 17.03
BASIN 2B AREA 100 5.673 11.9952 80.07
BASIN 3 AREA 2 1.400 12.1618 11.02
BASIN 3 AREA 100 8.652 12.1618 97.17
BASIN 4 AREA 2 .059 12.0785 .73
BASIN 4 AREA 100 .207 12.0785 2.57
DA 1 WP AREA 2 1.867 12.1618 21.22
DA 1 WP AREA 100 6.223 12.0785 69.39
DA 2 WP AREA 2 .213 11.9952 3.00
DA 2 WP AREA 100 1.125 11.9952 18.64

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Master Network Summary Page 1.02
Name.... Watershed
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW
MASTER NETWORK SUMMARY
SCS Unit Hydrograph Method
(*Node=Outfall; +Node=Diversion;)
(Trun= HYG Truncation: Blank=None; L=Left; R=Rt; LR=Left&Rt)

Max
Return HYG Vol Qpeak Qpeak Max WSEL Pond Storage
Node ID Type Event ac-ft Trun hrs cfs ft ac-ft

DA 3 WP AREA 2 1.596 11.9952 26.18
DA 3 WP AREA 100 4.989 11.9952 78.47
GORMAN ST JCT 2 4.550 12.3284 30.00
GORMAN ST JCT 100 22.866 12.2451 186.74
JUN 30 JCT 2 5.811 12.1618 37.88
JUN 30 JCT 100 28.539 12.1618 230.06
JUNC 20 JCT 2 10.866 12.1618 49.95
JUNC 20 JCT 100 49.506 12.0785 467.74
*OUTFALL 1 JCT 2 10.866 12.1618 49.95
*OUTFALL 1 JCT 100 49.506 12.0785 467.74
*OUTFALL 2 JCT 2 .059 12.0785 .73
*OUTFALL 2 JCT 100 .207 12.0785 2.57
WET POND IN POND 2 3.676 11.9952 45.05
WET POND IN POND 100 12.337 11.9952 153.73
WET POND OUT POND 2 3.656 12.6616 7.93 410.59 1.898
WET POND OUT POND 100 12.315 12.0785 149.49 411.36 2.451

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type.... Design Storms Page 2.01
Name.... Wake County
File.... K:\03\03-200\03209\H&H\
Title... Project Date: 9/1/2004
Project Engineer: wr
Project Title: Watershed
Project Comments:
DESIGN STORMS SUMMARY
Design Storm File,ID = Wake County

Storm Tag Name = 2

Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 2 yr
Total Rainfall.Depth= 3.6000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs
Storm Tag Name = 100

Data Type, File, ID = Synthetic Storm TypeII 24hr
Storm Frequency = 100 yr
Total Rainfall Depth= 8.1000 in
Duration Multiplier = 1
Resulting Duration = 24.0000 hrs
Resulting Start Time= .0000 hrs Step= .1000 hrs End= 24.0000 hrs

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.01
Name.... BASIN 1
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 97.55 ft
2yr, 24hr P 3.6000 in
Slope .020500 ft/ft
Avg.Velocity .12 ft/sec
Segment #1 Time: .2177 hrs
_
Segment #2: Tc: TR-55 Shallow

Hydraulic-Length 2212.80 ft
Slope .016300 ft/ft
Unpaved
Avg.Velocity 2.06 ft/sec
Segment #2 Time: .2984 hrs

Segment #3: Tc: TR-55 Channel

Flow Area 4.0000 sq.ft
Wetted Perimeter 6.00 ft
Hydraulic Radius .67 ft
Slope .009800 ft/ft
Mannings n .0400
Hydraulic Length 1432.76 ft
Avg.Velocity 2.81 ft/sec
Segment #3 Time: .1414 hrs

Total Tc: .6575 hrs

S/N: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.02
Name.... BASIN 1

File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

Tc Equations used...

SCS TR-55 Sheet Flow
T c = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))

Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, %
SCS TR-55 Shallow Concentrated Flow
Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)

Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

f

" ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.03
Name.... BASIN 1
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

SCS Channel Flow
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n
Tc = (Lf / V) / (3600sec/hr)

Where: R = Hydraulic radius
Aq = Flow area, sq.ft.
Wp = Wetted perimeter, ft
V = Velocity, ft/sec
Sf = Slope, ft/ft
n = Mannings n
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT.

Type.... Tc Calcs Page 3.04
Name.... BASIN 2A

File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: TR-55 Sheet
Mannings n .4000
Hydraulic Length 100.00 ft
2yr, 24hr P 3.6000 in
Slope .059900 ft/ft
Avg.Velocity .13 ft/sec
Segment #1 Time: .2176 hrs

Segment #2: Tc: TR-55 Shallow
Hydraulic Length 290.04 ft
Slope .048300 ft/ft
Unpaved
Avg.Velocity 3.55 ft/sec
segment #2 Time: .0227 hrs

Segment #3: Tc: TR-55 Channel
Flow Area 9.0000 sq.ft
Wetted Perimeter 9:00 ft
Hydraulic Radius 1.00 ft
Slope .021500 ft/ft
Mannings n .0400
Hydraulic Length 186.36 ft
Avg.Velocity 5.46 ft/sec
Segment #3 Time: .0095 hrs

Total Tc: .2498 hrs
-

S/N: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.05
Name.... BASIN 2A
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

Tc Equations used...

SCS TR-55 Sheet Flow

Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, %
SCS TR-55 Shallow Concentrated Flow

Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)

Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN:' 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.06
Name.... BASIN 2A
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

SCS Channel Flow
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n

Tc = (Lf / V) / (3600sec/hr)
Where: R = Hydraulic radius
Aq = Flow area, sq.ft.
Wp = Wetted perimeter, ft
V = Velocity, ft/sec
Sf = Slope, ft/ft
n = Mannings n
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.07
Name..:. BASIN 2B
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 100.00 ft
2yr, 24hr P 3.6000 in
Slope .029960 ft/ft
Avg.Velocity .15 ft/sec
Segment #1 Time: .1908 hrs

Segment #2: Tc: TR-55 Shallow

Hydraulic Length 611.00 ft
Slope .065500 ft/ft
Unpaved
Avg.Velocity 4.13 ft/sec
Segment #2 Time: .0411 hrs

Segment #3: Tc: TR-55 Channel

Flow Area 9.0000 sq.ft
Wetted Perimeter 9.00 ft
Hydraulic Radius 1.00 ft
Slope .155300 ft/ft
Mannings n .0400
Hydraulic Length 386.50 ft
Avg.Velocity 14.68 ft/sec
Segment #3 Time: .0073 hrs

Total Tc: .2392 hrs

S/N: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.08
Name.... BASIN 2B

File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

Tc Equations used...

SCS TR-55 Sheet Flow
Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))

Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, %
SCS TR-55 Shallow Concentrated Flow
Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)

Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type:... Tc Calcs Page 3.09
Name.... BASIN 2B
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

SCS Channel Flow
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n
Tc = (Lf / V) / (3600sec/hr)

Where: R = Hydraulic radius
Aq = Flow area, sq.ft.
Wp = Wetted perimeter, ft
V = Velocity, ft/sec
Sf = Slope, ft/ft
n = Mannings n
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.10
Name.... BASIN 3

File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 100.00 ft
2yr, 24hr P 3.6000 in
Slope .017900 ft/ft
Avg.Velocity .12 ft/sec
Segment #1 Time: .2344 hrs

Segment #2: Tc: TR-55 Shallow
Hydraulic Length 1297.50 ft
Slope .047800 ft/ft
Unpaved
Avg.Velocity 3.53 ft/sec
Segment #2 Time: .1022 hrs

Segment #3: Tc: TR-55 Channel
Flow Area 9.0000 sq.ft
Wetted Perimeter 9.00 ft
Hydraulic Radius 1.00 ft
Slope .005950 ft/ft
Mannings n .0400
Hydraulic Length 672.72 ft
Avg.Velocity 2.87 ft/sec
Segment #3 Time: .0650 hrs

Total Tc: .4016 hrs

S/N: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.11
Name.... BASIN 3
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

Tc Equations used...

SCS TR-55 Sheet Flow

Tc = (.007 * ((n * Lf)**0.8).) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, %
SCS TR-55 Shallow Concentrated Flow

Unpaved surface:
V = 16.1345 * (Sf**0.5)
Paved surface:
V = 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)

Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT ,

Type.... Tc Calcs Page 3.12
Name.... BASIN 3
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

SCS Channel Flow
R = Aq / Wp
V = (1.49 * (R**(2/3)) * (Sf**-0.5)) / n

Tc = (Lf / V) / (3600sec/hr)
Where: R = Hydraulic radius
Aq = Flow area, sq.ft.
Wp = Wetted perimeter, ft
V = Velocity, ft/sec
Sf = Slope, ft/ft
n = Mannings n
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.13
Name.... BASIN 4
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 162.80 ft
2yr, 24hr P 3.6000 in
Slope .018400 ft/ft
Avg.Velocity .13 ft/sec
Segment #1 Time: .3424 hrs

Total Tc: .3424 hrs

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.14
Name.... BASIN 4
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

Tc Equations used...

SCS TR-55 Sheet Flow
Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))

Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, %

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

I
ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.15
Name.... DA 1 WP
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 64.37 ft
2yr, 24hr P 3.6000 in
Slope .031070 ft/ft
Avg.Velocity .14 ft/sec
Segment #1 Time: .1322 hrs

Segment #2: Tc: TR-55 Shallow
Hydraulic Length 711.25 ft
Slope .019700 ft/ft
Unpaved
Avg.Velocity 2.26 ft/sec
Segment #2 Time: .0872 hrs

Segment #3: Tc: TR-55 Shallow
Hydraulic Length 179.47 ft
Slope .033400 ft/ft
Paved
Avg.Velocity 3.72 ft/sec
Segment #3 Time: .0134 hrs

Segment #4: Tc: User'Defined
Segment #4 Time: .1670 hrs

Total Tc: .3998 hrs

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.16
Name.... DA 1 WP
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

Tc Equations used...

User Defined
Tc = Value entered by user

Where: Tc = Time of concentration

SCS TR-55 Sheet Flow

T c = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))
Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope, %
SCS TR-55 Shallow Concentrated Flow

Unpaved-surface:
V = 16.1345 * (Sf**0.5)
Paved.surface:
V =.20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs.
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.17
Name.... DA 2 WP
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: TR-55 Sheet
Mannings n .2400
Hydraulic Length 78.37 ft
2yr, 24hr P 3.6000 in
Slope .051000 ft/ft
Avg.Velocity .17 ft/sec
Segment #1 Time: .1269 hrs

Segment #2: Tc: TR-55 Shallow

Hydraulic Length 488.32 ft
Slope .069600 ft/ft
Unpaved
Avg.Velocity 4.26 ft/sec
Segment #2 Time: .0319 hrs

-
Total Tc: .1588 hrs

S/N: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD ,
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.18
Name.... DA 2 WP
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

Tc Equations used...

SCS TR-55 Sheet Flow
Tc = (.007 * ((n * Lf)**0.8)) / ((P**.5) * (Sf**.4))

Where: Tc = Time of concentration, hrs
n = Mannings n
Lf = Flow length, ft
P = 2yr, 24hr Rain depth, inches
Sf = Slope,
SCS TR-55 Shallow Concentrated Flow
Unpaved surface:
V = 16.1345 * (Sf**0.5)

Paved surface:
V 20.3282 * (Sf**0.5)
Tc = (Lf / V) / (3600sec/hr)
Where: V = Velocity, ft/sec
Sf = Slope, ft/ft
Tc = Time of concentration, hrs
Lf = Flow length, ft

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.19
Name.... DA 3 WP
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

TIME OF CONCENTRATION CALCULATOR

Segment #1: Tc: User Defined

Segment #1 Time: .1670 hrs

Total Tc: .1670 hrs

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Tc Calcs Page 3.20
Name.... DA 3 WP

File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

Tc Equations used...

User Defined
T c = Value entered by user

Where: Tc = Time of concentration

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type.... Runoff CN-Area Page 4.01
Name.... BASIN 1
File.... K:\03\03-200\03209\H&H\GORMAN_POST NEWPOND.PPW

RUNOFF CURVE NUMBER DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C %UC CN

Woods - good 70 7.316 70.00
Woods - good 55 24.773 55.00
Pasture, grassland, or range - good 74 .537 74.00
Pasture, grassland, or range - good 61 27.043 61.00
Impervious Areas - Paved parking to 98 5.653 98.00
Residential Districts - 1/8 acre (t 85 1.299 85.00
Impervious Areas - Paved; open ditc 89 .292 89.00
COMPOSITE AREA & WEIGHTED CN 66.913 63.58 (64)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Runoff CN-Area Page 4.02
Name.... BASIN 2A
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

RUNOFF CURVE NUMBER DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C %UC CN

Impervious Areas - Paved parking to 98 .246 98.00
Residential Districts - 1/8 acre (t 90 .302 90.00
Residential Districts - 1/8 acre (t 85 .685 85.00
Pasture, grassland, or range - good 61 .616 61.00
Woods - good 55 .682 55.00
Woods - good 70 .869 70.00
COMPOSITE AREA & WEIGHTED CN 3.400 72.19 (72)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type.... Runoff CN-Area Page 4.03
Name.... BASIN 2B
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

RUNOFF CURVE NUMBER DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C oUC CN

Impervious Areas - Paved parking to 98 3.445 98.00
Pasture, grassland, or range - good 61 6.826 61.00
Woods - good 55 4.123 55.00
Woods - good 70 1.367 70.00
COMPOSITE AREA & WEIGHTED CN 15.761 68.30 (68)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOP2IENT

Type.... Runoff CN-Area Page 4.04
Name.... BASIN 3
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

RUNOFF CURVE NUMBER DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C RUC CN

Pasture, grassland, or range - good 61 14.441 61.00
Woods - good 55 14.648 55.00
Woods - good 70 2.402 70.00
COMPOSITE AREA & WEIGHTED CN 31.491 58.90 (59)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Runoff CN-Area Page 4.05
Name.... BASIN 4
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

RUNOFF CURVE NUMBER DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C RUC CN

Residential Districts - 1/8 acre (t 85 .330 85.00
Pasture, grassland, or range - good 61 .123 61.00
COMPOSITE AREA & WEIGHTED CN .453 78.48 (78)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type.... Runoff CN-Area Page 4.06
Name.... DA 1 WP

File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW
RUNOFF CURVE NUMBER-DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C %UC CN

Impervious Areas - Paved parking to 98 6.239 98.00
Pasture, grassland, or range - good 61 5.993 61.00
Impervious Areas - Paved; open ditc 89 .823 89.00
COMPOSITE AREA & WEIGHTED CN 13.055 80.45 (80)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Runoff CN-Area Page 4.07
Name.... DA 2 WP
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

RUNOFF CURVE NUMBER DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C %UC CN

Impervious Areas - Paved parking to 98 .311 98.00
Woods - good 55 .549 55.00
Pasture, grassland, or range - good 61 2.745 61.00
COMPOSITE AREA & WEIGHTED CN 3.605 63.28 (63)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Runoff CN-Area Page 4.08
Name.... DA 3 WP
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

RUNOFF CURVE NUMBER DATA

Impervious
Area Adjustment Adjusted
Soil/Surface Description CN acres %C %UC CN

Residential Districts - 1/8 acre (t 85 4.804 85.00
Residential Districts - 1/8 acre (t 90 .073 90.00
Pasture, grassland, or range - good 61 1.267 61.00
Impervious Areas - Paved; open ditc 89 3.719 89.00
COMPOSITE AREA & WEIGHTED CN 9.863 83.46 (83)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type.... Vol: Elev-Area Page 5.01
Name.... WET POND
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

Elevation Planimeter Area Al+A2+sgr(Al*A2) Volume Volume Sum
(ft) (sq.in) (acres) (acres) (ac-ft) (ac-ft)

407.50 .5330 .0000 .000 .000
408.50 .5840 1.6749 .558 .558
409.50 .6370 1.8309 .610 1.169
410.50 .6920 1.9929 .664 1.833
411.50 .7480 2.1595 .720 2.553
POND VOLUME EQUATIONS
* Incremental volume computed by the Conic Method for Reservoir Volumes.

Volume = (1/3) * (EL2-EL1) * (Areal + Area2 + sq.rt.(Areal*Area2))
where: ELI, EL2 Lower and upper elevations of the increment
Areal,Area2 = Areas computed for ELI, EL2, respectively
Volume = Incremental volume between ELI and EL2

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Outlet Input Data Page 6.01
Name.... Wet Pond

File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

REQUESTED POND WS ELEVATIONS:
Min. Elev.= 407.50 ft
Increment = .05 ft
Max. Elev.= 411.50 ft

OUTLET CONNECTIVITY

Forward Flow Only (Upstream to DnStream)
Reverse Flow Only (DnStream to Upstream)
Forward and Reverse Both Allowed
Structure No. Outfall E1, ft E2, ft

Weir-Rectangular DM TW 411.500 411.500
Weir-Rectangular SW TW 410.500 411.500
Orifice-Area 01 CU 409.500 411.500
Orifice-Circular OR CU 407.500 411.500
Culvert-Circular CU TW 404.500 411.500
TW SETUP, DS Channel

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT
Type.... Outlet Input Data Page 6.02
Name.... Wet Pond

File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

OUTLET STRUCTURE INPUT DATA

Structure ID = DM
Structure Type = Weir-Rectangular

# of Openings = 1
Crest Elev. = 411.50 ft
Weir Length = 380.00 ft
Weir Coeff. = 2.800000
Weir TW effects (Use adjustment equation)

Structure ID = SW
Structure Type = Weir-Rectangular

# of Openings = 1
Crest Elev. = 410.50 ft
Weir Length = 65.00 ft
Weir Coeff. = 2.800000
Weir TW effects (Use adjustment equation)

Structure ID = Ol
Structure Type = Orifice-Area

# of Openings = 1
Invert Elev. = 409.50 ft
Area = .5000 sq.ft
Top of Orifice = 410.00 ft
Datum Elev. = 409.75 ft
Orifice Coeff. _ .600

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT 4

Type.... Outlet Input Data Page 6.03
Name.... Wet Pond
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

OUTLET STRUCTURE INPUT DATA

Structure ID = OR
Structure Type = Orifice-Circular

# of Openings = 1
Invert Elev. = 407.50 ft
Diameter = .2500 ft
Orifice Coeff. _ .600
Structure ID = CU
Structure Type = Culvert-Circular

No. Barrels = 1
Barrel Diameter = 1.0000 ft
Upstream Invert = 404.50 ft
Dnstream Invert = 404.00 ft
Horiz. Length = 75.00 ft
Barrel Length = 75.00 ft
Barrel Slope = .00667 ft/ft
OUTLET CONTROL DATA...
Mannings n = .0130
Ke = .5000 (forward entrance loss)
Kb = .031274 (per ft of full flow)
Kr = .5000 (reverse entrance loss)
HW Convergence = .001 ft
INLET CONTROL DATA...
Equation form = 1
Inlet Control K = .0098
Inlet Control M = 2.0000
Inlet Control c = .03980
Inlet Control Y = .6700
T1 ratio (HW/D) = 1.156
72 ratio (HW/D) = 1.303
Slope Factor = -.500
Use unsubmerged inlet control Form 1 equ. below T1 elev.
Use submerged inlet control Form 1 equ. above T2 elev.
In transition zone between unsubmerged and submerged inlet control,
interpolate between flows at T1 & T2...
At T1 Elev = 405.66 ft Flow = 2.75 cfs
At T2 Elev = 405.80 ft Flow = 3.14 cfs

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Outlet Input Data Page 6.04
Name.... Wet Pond
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

OUTLET STRUCTURE INPUT DATA

Structure ID = TW
Structure Type = TW SETUP, DS Channel

FREE OUTFALL CONDITIONS SPECIFIED
CONVERGENCE TOLERANCES...
Maximum Iterations= 30
Min. TW tolerance = .01 ft
Max. TW tolerance = .01 ft
Min. HW tolerance = .01 ft
Max. HW tolerance = .01 ft
Min. Q tolerance = .10 cfs
Max. Q tolerance = .10 cfs

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACK OUTPUT - POST-DEVELOPMENT

Type.... Composite Rating Curve Page 6.05
Name.... Wet Pond

File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

COMPOSITE OUTFLOW SUMMARY
WS Elev, Total Q Notes
Converge
Elev. Q TW Elev Error
ft cfs ft +/-ft Contributing Structures

407.50 .00 Free Outfall (no Q: DM,SW,OI,OR,CU)
407.55 .00 Free Outfall OR,CU (no Q: DM,SW,01)
407.60 .02 Free Outfall OR,CU (no Q: DM,SW,01)
407.65 .03 Free Outfall OR,CU (no Q: DM,SW,01)
407.70 .06 Free Outfall OR,CU (no Q: DM,SW,01)
407.75 .08 Free Outfall OR,CU (no Q: DM,SW,01)
407.80 .10 Free Outfall OR,CU (no Q: DM,SW,01)
407.85 .11 Free Outfall OR,CU (no Q: DM,SW,01)
407.90 .12 Free Outfall OR,CU (no Q: DM,SW,01)
407.95 .13 Free Outfall OR,CU (no Q: DM,SW,01)
408.00 .14 Free Outfall OR,CU (no Q: DM,SW,01)
408.05 .15 Free Outfall OR,CU (no Q: DM,SW,01)
408.10 .16 Free Outfall OR,CU (no Q: DM,SW,01)
408.15 .17 Free Outfall OR,CU (no Q: DM,SW,01)
408.20 .18 Free Outfall OR,CU (no Q: DM,SW,01)
408.25 .19 Free Outfall OR,CU (no Q: DM,SW,01)
408.30 .19 Free Outfall OR,CU (no Q: DM,SW,01)
408.35 .20 Free Outfall OR,CU (no Q: DM,SW,01)
408.40 .21 Free Outfall OR,CU (no Q: DM,SW,01)
408.45 .21 Free Outfall OR,CU (no Q: DM,SW,01)
408.50 .22 Free Outfall OR,CU (no Q: DM,SW,01)
408.55 .23 Free Outfall OR,CU (no Q: DM,SW,01)
408.60 .23 Free Outfall OR,CU (no Q: DM,SW,01)
408.65 .24 Free Outfall OR,CU (no Q: DM,SW,01)
408.70 .24 Free Outfall OR,CU (no Q: DM,SW,O1)
408.75 .25 Free Outfall OR,CU (no Q: DM,SW,01)
408.80 .26 Free Outfall OR,CU (no Q: DM,SW,01)
408.85 .26• Free Outfall OR,CU (no Q: DM,SW,01)
408.90 .27 Free Outfall OR,CU (no Q: DM,SW,01)
408.95 .27 Free Outfall OR,CU (no Q: DM,SW,01)
409.00 .28 Free Outfall OR,CU (no Q: DM,SW,01)
409.05 .28 Free Outfall OR,CU (no Q: DM,SW,01)
409.10 .29 Free Outfall OR,CU (no Q: DM,SW,01)
409.15 .29 Free Outfall OR,CU (no Q: DM,SW,01)
409.20 .30 Free Outfall OR,CU (no Q: DM,SW,01)
409.25 .30 Free Outfall OR,CU (no Q: DM,SW,01)
409.30 .31 Free Outfall OR,CU (no Q: DM,SW,01)
409.35 .31 Free Outfall OR,CU (no Q: DM,SW,01)
SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type.... Composite Rating Curve Page 6.06
Name.... Wet Pond
File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

COMPOSITE OUTFLOW SUMMARY

WS Elev, Total Q Notes
Converge
Elev. Q TW Elev Error
ft cfs ft +/-ft Contributing Structures

409.40 .31 Free Outfall OR,CU (no Q: DM,SW,01)
409.45 .32 Free Outfall OR,CU (no Q: DM,SW,01)
409.50 .32 Free Outfall OR,CU (no Q: DM,SW,01)
409.55 .45 Free Outfall 01,OR,CU (no Q: DM,SW)
409.60 .57 Free Outfall 01,OR,CU (no Q: DM,SW)
409.65 .70 Free Outfall 01,OR,CU (no Q: DM,SW)
409.70 .82 Free Outfall 01,OR,CU (no Q: DM,SW)
409.75 .95 Free Outfall 01,OR,CU (no Q: DM,SW)
409.80 1.07 Free Outfall 01,OR,CU (no Q: DM,SW)
409.85 1.19 Free Outfall 01,OR,CU (no Q: DM,SW)
409.90 1.32 Free Outfall 01,OR,CU (no Q: DM,SW)
409.95 1.44 Free Outfall 01,OR,CU (no Q: DM,SW)
410.00 1.57 Free Outfall 01,OR,CU (no Q: DM,SW)
410.05 1.69 Free Outfall 01,OR,CU (no Q: DM,SW)
410.10 1.80 Free Outfall 01,OR,CU (no Q: DM,SW)
410.15 1.90 Free Outfall 01,OR,CU (no Q: DM,SW)
410.20 1.99 Free Outfall 01,OR,CU (no Q: DM,SW)
410.25 2.08 Free Outfall 01,OR,CU (no Q: DM,SW)
410.30 2.17 Free Outfall 01,OR,CU (no Q: DM,SW)
410.35 2.25 Free Outfall 01,OR,CU (no Q: DM,SW)
410.40. 2.33 Free Outfall 01,OR,CU (no Q: DM,SW)
410.45 2.41 Free Outfall 01,OR,CU (no Q: DM,SW)
410.50 2.48 Free Outfall 01,OR,CU (no Q: DM,SW)
410.55 4.59 Free Outfall SW,O1,OR,CU (no Q: DM)
410.60 8.38 Free Outfall SW,O1,OR,CU (no Q: DM)
410.65 13.27 Free Outfall SW,O1,OR,CU (no Q: DM)
410.70 19.04 Free Outfall SW,O1,OR,CU (no Q: DM)
410.75 25.57 Free Outfall SW,O1,OR,CU (no Q: DM)
410.80 32.79 Free Outfall SW,O1,OR,CU (no Q: DM)
410.85 40.63 Free Outfall SW,O1,OR,CU (no Q: DM)
410.90 49.05 Free Outfall SW,O1,OR,CU (no Q: DM)
410.95 58.01 Free Outfall SW,O1,OR,CU (no Q: DM)
411.00 67.47 Free Outfall SW,O1,OR,CU (no Q: DM)
411.05 77.41 Free Outfall SW,O1,OR,CU (no Q: DM)
411.10 87.82 Free Outfall SW,O1,OR,CU (no Q: DM)
411.15 98.67 Free Outfall SW,O1,OR,CU (no Q: DM)
411.20 109.94 Free Outfall SW,O1,OR,CU (no Q: DM)
411.25 121.61 Free Outfall SW,O1,OR,CU (no Q: DM)
SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

ATLANTIC HOMES - TRYON RD
PONDPACR OUTPUT - POST-DEVELOPMENT

Type.... Composite Rating Curve Page 6.07
Name.... Wet Pond

File.... K:\03\03-200\03209\H&H\GORMAN POST NEWPOND.PPW

COMPOSITE OUTFLOW SUMMARY
WS Elev, Total Q Notes
Converge
Elev. Q TW Elev Error
ft cfs ft +/-ft Contributing Structures

411.30 133.67 Free Outfall SW,OI,OR,CU (no Q: DM)
411.35 146.13 Free Outfall SW,Ol,OR,CU (no Q: DM)
411.40 158.94 Free Outfall SW,OI,OR,CU (no Q: DM)
411.45 172.13 Free Outfall SW,01,OR,CU (no Q: DM)
411.50 185.65 Free Outfall SW,OI,OR,CU (no Q: DM)

SIN: 22160372E1C5 Withers & Ravenel
PondPack Ver. 9.0029 Time: 3:44 PM Date: 10/14/2004

NITROGEN

CALCULATIONS

Atlantic Homes - Tryon Rd ii W&R Project 203209
Stormwater Management Report September 2004

Exhibit 3-1 Method 1 for Quantifying TN Export from
Residential Developments when Building and Driveway
Footprints are Not Shown

Step 1: Determine area for each type of land use and enter in
Column (2).
Step 2: Total the areas for each type of land use and enter at the
bottom of Column (2).
Step 3: Determine the TN export coefficient associated with right-
of-way using Figure 3.1.
Step 4: Determine the TN export coefficient associated with lots
using Figure 3-2.
Step 5: Multiply the areas in Column (2) by the TN export
coefficients in Column (3) and enter in Column (4).
Step 6: Total the TN exports for each type of land use and enter at
the bottom of Column (4).
Step 7: Determine the export coefficient for site by dividing the total
TN export from uses at the bottom of Column (4) by the
total area at the bottom of Column (2) and enter it in at the
bottom of Column (5).
(Z) (3) (4) (5)
Type of Land Cover Site TN Export TN Export TN Export
Area Coeff. by Land Use From Site
Acres Ibs/a r Ibs! r Ibs/actyr
Permanently preserved undisturbed
open sace forest, unmown meadow) q , i&0 6 Z .o` t
Permanently preserved managed
5 • c) 1.2
open space (grass, landscaping, etc. 3
Right-of-way (read TN export from
1 .O Figure 1)
Lots (read TN export from Figure 2) • a~~
Total A) .(03 Average for Site

City of Raleigh January 2002
StormwaterDesign Manual Page 79

r

Method 2 is for residential, commercial and industrial developments
when the entire footprint of the roads, parking lots, buildings and any
other built-upon area is shown on the site plans. This method is
simpler and more accurate since it does not require estimating the
impervious surface. Method 2 is shown in Exhibit 3.2.

Exhibit 3-2 Method 2 for Quantifying TN Export from
Residential / Industrial / Commercial
Developments when Footprints of all Impervious
Surfaces are Shown
Step 1: Determine area for each type of land use and enter in
Column (2).
Step 2: Total the areas for each type of land use and enter at the
bottom of Column (2).
Step 3: Multiply the areas in Column (2) by the TN export
coefficients in Column (3) and enter in Column (4).
Step 4: Total the TN exports for each type of land use and enter at
the bottom of Column (4).
Step 5: Determine the export coefficient for site by dividing the total
TN export from uses at the bottom of Column (4) by the
- total area at the bottom of Column (2) and enter the result
at the bottom of Column (5).

(2) (3) (4) (5)
Type of Land Cover Site TN Export TN Export TN Export
Area Coeff. by Land Use From Site
Acres (lbs/aclyr) Ibs lbs/a
Permanently preserved undisturbed 0.6
O
open sace oestunmown meadow
Permanently preserved managed D 1.2 0
open sace (grass, landscaping, etc.
Impervious surfaces (roads, parking 21.2 Z
lots, driveways, roofs, paved storage C~
areas, etc.
Total
Average for Site
011 E{ia\YL 51~E'. • 295• 04 AorCS ~ S.W. 1j,1-6 1bs1 ~ V
p,,~crage, -TN &'Y~pov-)-
~~c-,6 Wek?on& ~ Cv.17 1 bslacl.
YeAuo,4 i &V\s
Q ~e,r 25~~ 1lfe~~o~nd = ~•ly3 ~bs~°~`~M

City of Raleigh Ye y~ ~p January 2002
StormwaterDesign Manual Page 81
Ca she~s de;~a~ led
Please see,o`44.gL Jie d spYeadl
kca

i

Figure 3-1 Total Nitrogen Export from Right-of-Way

25.0

20.0
a
i
15.0-

10.0-
U1 Z
5.0

0.0 - E-E!
0% 20% 40% 60% 80% 100% 120%
Percentage of Right-of-Way that is Pavement

Figure 3-2 Total Nitrogen Export from Lots

12.00

10.00

a. 6.00
V
W
it
a_
e
r 6.00
CL
X
W
Z
F-
4.00 .
3•%
2.00
0.00
0 2 4 6 8 10 12 14 16 18 20 22 24 26 28 30 32
Number of Dwelling Units per Acre
City of Raleigh January 2002
StormwaterDesign Manual Page 80

Nitrogen Control Plan
Residential Subdivision with no known building footprints

Project Title: Atlantic Homes - Tryon Rd
Part I. Riparian Buffers
Area includes riparian buffers? [ ] No [x] Yes [ ] Exempt
If yes, [X] 50 foot [ ] 100 foot
River Basin? [ X Neuse [ ] Cape. Fear
Basis for Exemption
Show buffers on site plan.
Part 11. Nitrogen. Calculations:
a.. Subdivision. Information
Number of lots 67 Average house size +/-3000 sf
Number of lots / acre 2.61 Amount of. Right-of-Way 2.97 ac
Totat area of. lots (excluding Percent of Right-of-Way
R/W and open space) 7.49 ac that is impervious. area 50.10%
Average lot size 5500 sf Total estimated impervious area 1.49 ac
b... Pre-development loading: TN Export
Area TR export coeff from use
Type of Land. Cover (acres) (Ibs/ac/yr) (Ibs/ )
Permanently protected undisturbed open
space (forest, unmown meadow) 25.64 0.6 15.38
Permanently protected managed. open space
(grass, landscaping, etc.) 0 1.2 0
Impervious Area 0 21.2 0
TOTAL 25.64 15.38
Nitrogen Loading Rate (Ibs/ac/yr) = 0.60
c... Post-development loading: TN. Export
Area TN export coeff from use
Type of. Land Cover (acres) (Ibs/ac/yr) Ibs/yr)
Permanently protected undisturbed open
space (forest, unmown. meadow) 4.84 0.6 2.91
Permanently protected managed open space
(grass, landscaping, etc.) 5.93 1.2 7.12
Impervious. Surface 4.40 21.2 93.32
Right-of-Way (read TN export from Graph 1) 2.97 26.77
Lots (read TN. export from. Graph 2) 7.49 If 28.47
TOTAL 25.64 158.58
Nitrogen Loading. Rate. (Ibs/ac/yr) = 6.18
Proposed BMP(s) Wet Pond
Nitrogen Load after BMPs. = 4.63 Ibs/ac/yr
Nitrogen Load offset by Payments = 1.03 Ibs/ac/yr Estimated Buy Down = $8,722
Net change in on-site N Load = 2.58 Ibs/ac/yr

Atlantic Homes - Tryon Road Nitrogen Loading Calculations

Project Name: Atlantic Homes - Tryon Rd Date: 9/8/2004
Project 203185 Computed by: SAH

TOTAL TRACT
Total Area: sgft. = 25.64 ac.
Right-of-Way Area: sqft. = 2.97 ac. 50 % Impervious
Right-of-Way Impervious sqft. = 1.49 ac.
Natural Open Space Area: sqft. = 4.84 ac.
Managed Open Space Area: sqft. = 5.93 ac. .
Lot Area: sgft. = 7.49 ac. 67 Lots
2.61 du/ac
Estimated Pre-Development TN Loading
Type of Land Cover Acres TN Export Coeff. TN EXPORT (Ibs/yr)
Permanently Protected Undisturbed Area 0.6 15.38
Permanently Protected Managed Area 1.2 0.00
Impervious Surface 21.2 0.00
Totals 25.64 15.38
Estimated Post-Development TN Loading
Drainage Area A. Wet Pond
Type of Land Cover Acres TN Export Coeff. TN EXPORT (Ibs/yr)
Permanently Protected Undisturbed Area 0.00 0.6 0.00
Permanently Protected Managed Area 4.11 1.2 4.94
Impervious Surface 4.11 21.2 87.17
Lot Area 4.88 3.8 18.53
R1W Area 2.68 9.0 24.14
L Totals 15.78 134.77
Estimated BMP Reduction for Wet Pond: 25%
Estimated Drainage Area A Nitrogen Loading Reduction: 33.69 Ibs/yr

Drainage Area B: Remainder of Site
Type of Land Cover Acres TN Export Coeff. TN EXPORT (Ibs/yr)
Permanently Protected Undisturbed Area 4.84 0.6 2.91
Permanently Protected Managed Area 1.82 1.2 2.18
Lot Area 2.62 3.8 9.94
R/W Area 0.29 9.0 2.63
Totals 9.57 17.65
Estimated BMP Reduction: 0%
Estimated Drainage Area B Nitrogen Loading Reduction: 0.00 Ibs/yr
Estimated Project Pre-BMP TN Export: 152.43 Ibs/yr
Estimated Project BMP TN Removal: 33.69 Ibs/yr
Estimated Project TN Load Rate After BMPs: 4.63 lbs/ac/yr
Est imated Project Composite Nitrogen Loading Rate Reduction: 22.10 %

W A TFgQ . Michael F. Easley, Governor
z„._ .
William G. Ross Jr., Secretary
r7„ North Carolina Department of Environment and Natural Resources
Alan W. Klimek, P.E. Director
Division of Water Quality
November 4, 2004
Project Name: Mirror Lake
Wake County
EXPRESS REVIEW ACCEPTANCE LETTER

Villages of Swift Creek, LLC
Attn: Jonathon Skinner
729 Thimble Shoals Blvd., Suite 6C
Newport News, VA 23606
Fax [phone]

Subject Property; Located on Tryon Rd., just East of the intersection of Lake Dam Rd. & Tryon Rd. in
Wake County

Dear Mr. Skinner:

On November 4, 2004, the Wetlands/401 Unit of the Division of W~ter Quality received a Fax/email request from
Soil and. Environmental Consultants, PA regarding a project known as "Mirror Lake" for acceptance into the
Express Review Program. This letter advises you that your project,, will be accepted into the Express Review
Program once the following items are received: 1) a fee of $3,000.00 made payable to the North Carolina
Division of Water Quality, 2) seven complete and collated copies of the application and 3) seven copies of all
additional information pertaining to this project. Thank you for your attention to this matter.
Please keep in mind that the clock for this project will not start until receipt.of the completed application package
and required fee are received.

If you have any questions or wish to discuss these matters further please do not hesitate to call Cyndi Karoly at
919-733-9721 or Deborah Edwards at 733-9502.
Sincerely,

1 Alan W. Klimek, P.E., Director

AWK/dae

cc: Mike Horan- DWQ Regional Office
File copy
Central Files
Todd Preuninger-S&EC
Filename: Mirror Lake

NoithCarolina
401 Wetlands Certification Unit Qtunally
1650 Mail Service Center, Raleigh, North Carolina 27699-1650,,
2321 Crabtree Boulevard, Suite 250, Raleigh, North Carolina 27604
Phone: [phone]/ FAX [phone]/ Internet: lam://h2o.enr.state,ne.us/ncwetlands
An Equal Opportunity/Affirmative Action Employer-50% Recycled/10% Post Consumer Paper

MULTI COMMUNICATION REPORT

DATE NOV-4-2004 THU 10:24
NAME DWQ-WETLANDS
TEL [phone]
REF. NAME
-
COMMUNICATION MODE: TX
NO. FAX NAME/NUMBER START TIME TIME MODE PAGE RESULTS

619 87578730651 11-04 10:20 03'03" ECM 2/2 OK
619 98469467 11-04 10:23 00'49" ECM 2/2 OK

TOTAL TIME : 00:03' 52"
TOTAL PAGES 4

11/04/2004 06:30 FAX DW9 DORNEY U001

Soil & Environmental Consultants, PA
11010 Haven kidp- Road • Raleigh, North Carolina 27614 * Phone: [phone] * Fax: (919) $46-9467
wwwSandEC.com

FACSIMILE SHEET
FAX NO. (919) 84 4,067

DATE: I N2' Project Number-- !SGtd.cow-A

TO: NAME: CC:
COMPANY:_

FAX NUMBER; .

FROM- ~ ~ SUBJECT- '-1 V l JE ~W E~A>
The following items are being fared: Number of pages including transmittal sheet:

,.for Your Comments/Approval For Your Information
Per Our Conversation Per Your Request
Please Advise Please Call
Would Like To Discuss Please Handle
HARD COPY SENT:
US Regular Mail Hand Delivery
Overnight e-- o Hard Copy Sent

REMARKS:

IF YOU HAVE ANY PROBLEMS WITH THIS TRANSMSSXON, PLEASE
CON'TAC'T AT [phone].
*CONFIDENTIALITY NOTICE*
This transmission is intended only for the use of the individual or entity to which it is addressed and may contain
information that is privileged and, conficentiai. If the reader of this wessage is not the intended rccipicat, you are hereby
notified that any disclosure, distribution or copying of this information is strictly prohibited- If you have received this
transmission in error, please notify as indmediately by telephone and return the faxed documents to us at the above address
via the United Stages Postal Service.

rr rt wrp Office:
Charlotte-Office:
236 LcP'hilhp Court; Suite C 3817-E Lawadale Drive
Concord, NC 28025 Greensboro, NC 27455
Phone: [phone] phone:; [phone]
Fax: [phone] Fax:. [phone]
NOV-4-2004 THU 08:03 TEL:[phone] NAME:DWQ-WETLANDS P. 1

11/04/2004 08:30 FAX r DWQ DORNEY IM002

INITIAL INTEREST IN PARTICIPATION IN THE EXPRESS P ITTING PROGRAM
FOR THE 401 WATER QUALITY CERTIFICATION,
ISOLATED WETLAND PERMITTING
OR STREAM ORIGIN DETERMINATION PROGRAMS
February 25, 2004
Version 2
- VA Applicant Name:_

Applicant Address: s
-Cu.. Ck

Applicant's phone number: Fax number.. S - SAS- D us 1
Applicant's email address:

Consultant Name (if applicab e ; v a~'~'c'
Consultant address (if applicable)'

Consultant's phone number. <& A , Fax number; <PnW (o T"y--1r(,

Consultant's email address:

Type of action requested under t:ie: Express Review program (check all that apply)'

A0. Water (duality Certification,
-el
? Isotated Wetland Permit + 17 q 6
,tfRiparian Buffer Approval
0 Strom Origin Determination
# of Determinations Requested

Name of Project'

Property size (acres) County:

Nearest named stream (from USt3S topo map):
Please provide a brief description of this project (attach, site plan if available):

Please attach a map of site locati,)n using USGS 1:24,000 map and county soil survey"

NOV-4-2004 THU 08:03 TEL:[phone] NAME:DWQ-WETLANDS P. 2

11/04/2004 08:31 FAX DWq DORNEY 1@003

Location of project site - pleas( include reference to the county, nearest name town and highway number:
e

C.

Proposed impacts: _ 0.& :a Afi. Acres of wetlands
Acres of isolated wetlands

Linear feet of streams
Linear feet of isolated streams
A- ~gCy ~1 Square feet of protected stream buffers

Has consultant or applicant at:eaded any DWQ-sponsored training sessions in the past two years? If so,
please list which ones. __Pr ti <r ~~s
Which other environmentalpeerrmits will be needed for this project? Please list them below:

o1-k 'R !4~

Does this project require approval under the State Environmental Policy Act or National Environmental
Policy Act? R U
Does this project require appro•-al of a Variance from the NC Environmental Management Commission."

Are you aware of any local controversy concerning this project? If so, please describe the controversy and any
measures that have been taken with respect to public involvement.

tdr5

This form must be submitted via email (c/o 40IMpress(anemailhet fax [phone]) or hand-delivered
(Parkview Building, 2321 Crattree Blvd., Raleigh, NC 27604) within the first three (3) working days of the
month for the first three months of the Express Review Program (until January 1, 2004). Application
procedures after that time will be provided at a later date. Applicants who are selected to participate in the
Express Review Program will be notified via email or fax with one additional working day. Successful
applicants will then be instructed regarding detailed procedures for full application. Unsuccessful applicants
will be queried to determine if they want to be in the following month's selection process or whether they
want to follow the normal application process.
Please contact John Domey at $19-733-9646 if you have any questions regarding this form.

2

NOV-4-2004 THU 08:04 TEL:[phone] NAME:DWO-WETLANDS P. 3

11/04/2004 08:31 FAX i DW9 DORNEY 0 004

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Project No. Figure 1 - NO$ Map
8666.W1 Soil & Environmental Consultants, PA
~
Project Mgr.; WattWitherss & Chapel 11010 Raven Ridge Rd.- Raleigh, NC 27514
SC Wake County, NBC [phone] - (999) 846r9467
Web Page: www.SandEC.com
Scale:
1" = 2,000' _
NOV-4-2004 THU 08:04 TEL:[phone] NAME:DWQ-WETLANDS P. 4

11/04/2004 08:32 FAX DWQ DORNEY Q005

::,ty: r1•'G ; ,i~,r

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i

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ProjectM Scale:
8666-WI 1"=1320 Fi ure 2 - Soil Elurve
Project me: g X ~ Soil. & Environmental Consultants, PA
Mgr- SC 419/04 Watts Chapel 11016 Raven Ridge Rd.- Raleigh, NC 27614
Withers 8 Ravenel [phone] - [phone]
Raleigh. North Carolina Web Page: www.SandEC.com
Wake County Soil:-Survey
Sheet 66
NOV-4-2004 THU 08:05 TEL:[phone] NAME:DWQ-WETLANDS P. 5

EXPRESS REVIEW SCHEDULE

PROJECT NAME: rd f DWO

ACTION DATE 1
j
Acceptance letter
/L4
Application received
Initial review/letter ' I

Information received t 1 Z-
Field Meeting 12 P

Additional information letter

Information received
Office Meeting

Additional information letter

Information received
Expiration I

Issued/ jected (circle one) 1Z, d6;tl

WITHERS & R"ENEL, INC. 212b2

Invoice Number Date Voucher Amount Discounts Previous Pay Net Amount

203209 Tryon Road 11/4/04 0020343 3,000.00 3,000.00
NCDENR Totals 3,000.00 3,000.00
CCBChecki 1
I

REV

NUV ~ ~
51004 _ iArr
DENR - WATER QUALITY
OSANDSTOMwjj TES
9RANG j DENR - WATER QUALITp(AMM

~F?~""~o-wr~.rgi~Ml~

AR: COMPLETE THIS SECTION COMPLETE THIS SECTION ON DELIVERY
¦ Complete items 1, 2, and 3. Also complete Signature
item 4 if Restricted Delivery is desired. ? Agent
¦ Print your name and address on the reverse ? Addressee
so that we can return the card to you. B. Ftece ed by ( me Na C at o e've
¦ Attach this card to the back of the mailpiece,
or on the front if space permits. I L/
D. Is delivery address different from item 1? s
1. Article Addressed to: If YES, enter delivery address below: No
Villages of Swift Creek, LLC
729 Thimble Shoals Blvd, Suite 6C
Newport News, VA 23606 3. Service Type
DWQ 04-1796 - Wake aCertifled Mail ? Express Mail
? Registered O-Return Receipt for Merchandise
? Insured Mail ? C.O.D.
4. Restricted Delivery? (Extra Fee) ? Yes
2. Article Number 7004 1160 0002 2706 6882
(Transfer from service label)
PC Fnrm 3811 FahnMarv gnnd nnm-tip-. Roturn P-Int -'tn~sr

UNITED STATES POSTAL SERVICE First-Class Mail
Postage & Fees Paid
USPS
Permit No. G-10
• Sender: Please print your name, address, and ZIP+4 in this box •

NC DENR Division of Water Quality
- 401 Oversight/Express Unit
2321 Crabtree Boulevard, Suite 250
Raleigh, NC 27604

T' ' i[[i[~~[t[i[~f[[ii[[ee~:[i[ei[ e[~[1[ IIIIIIIII[[[[1ili
'l L

JER: COMPLETE THIS SECTION COMPLETE THIS SECTION ON DELIVERY
¦ Complete items 1, 2, and 3. Also complete A. Signature
Rem 4 If Restricted Delivery is desired. [3 Agent
¦ Print your name and address on the reverse X ? Addressee
so that we can return the card to you. B. Recei)TE ted Name ) C. Date of Delivery
¦ Attach this card to the back of the mailpiece, if CII,,
or on the front if space permits.
D. Is delivery address different from item 11 El es
1. Article Addressed to: if YES, enter delivery address below: ? No
Villages of Swift Creek, LLC
729 Thimble Shoals Blvd., Suite 6C
Newport News, VA 23606 3. Service Type
EXP# 04-1796 - Wake Ot Certified Mail ? Express Mail
? Registered K Return Receipt for Merchandise
? Insured Mail ? C.O.D.
4. Restricted Delivery? (Extra Fee) ? Yes
2. Article Number 7004 1160 0002 2706 6752
(Transfer from service
PC Fnrm 541411 Fnhn ions 9nnd nn-fir- Return RP ..Pint 1M.Yr,

UNITED STATES POSTAL SERVICE First-Class Mail
Postage & Fees Paid
LISPS
Permit No. G-10
• Sender: Please print your name, address, and ZIP+4 in this box •

NC DENR Division of Water Quality
401 Oversight Unit
2321 Crabtree Boulevard, Suite 250
Raleigh, NC 27604

= IIF~li~tlelt~let~lts~t~tt~tt~4iflitll~ftl~ti~ltiit!'~11!!l1~it