20061302 Ver 2_More Info Received_20080702

A R T I F E X
ENVIRONMENTAL
2363 Blake Street, Suite 202
Denver, CO 80205
[phone] phone
[phone] /ax
www.artifexed.com
July 1, 2008
E D inc
DESIGN
Ms. Cyndi Karoly
410 Oversight/Express Review Permitting Unit
1650 Mail Service Center
Raleigh, NC 27669-1650
RE: North Carolina Museum of Art-Museum Expansion Project
Stormwater Management Plan
House Creek [030402, 27-33-13, C, NSW]
Dear Ms. Karoly:
oV - 1302 v2.
flDnVL
J'A 2 L?
2008
BFI
We have reviewed the request for more information dated June, 2 2008 regarding the Stormwater
Management Plan for the North Carolina Museum of Art-Museum Expansion Project (DWQ Project #
06-1302). In order to meet the specified requirements, we have incorporated a stormwater wetland to
create a combined wetland/wetpond system.
Additionally, we have received notification from the U.S. Army Corps of Engineers, Raleigh Filed Office,
that the proposed site improvements will not require a 404 permit, based on the existing pond's history
as a stormwater management facility. We have enclosed this letter for your convenience.
Please note the following responses, and find the attached supplemental application package.
1. The stormwater best management practice has been modified to include a stormwater
wetland, and to function as combined Wet Detention Basin and Stormwater Wetland, in order
to meet the minimum requirements for TSS and TN reduction.
a. Stormwater flowing through the dissipater pad just west of the "E" (of the "Picture
This" feature) flows directly into the stormwater Swale. This Swale directs stormwater
into the existing stormwater pond, modified as described above.
Stormwater from all of the roadway drainage systems that were noted will also be
routed to the pond. The entry drive drains into the northern trunk line, which follows
the road and wraps around the northern side of both the new and existing gallery
buildings. This trunk line can be seen on the drawing Drainage Schematics Post-
Development, it runs through both POA-A and POC-C on the drawing.
The southern half of the existing north parking lot drains to the south and into the
northern trunk line described above. The northern half of the north parking lot, which
is existing and not augmented, drains into an existing storm sewer that runs along the
north and east side of the property. Both of these storm sewer lines empty into the
pond, which will be augmented as described above.
The parking lot adjacent to Blue Ridge Road is an existing parking lot and will not be
modified in the expansion. Nonetheless, stormwater from this lot also enters storm
sewers that drain to the pond. Part of the parking lot drains to the east into the
existing storm sewer in the Swale (south of the amphitheater). Another part of this
parking lot drains north into the north trunk line. The partition of this parking lot can be
• Page 2 July 1, 2008
seen in the basin delineations on the drawing Drainage Schematics Post-
Development.
2. The proposed BMP has been modified to include forebays at each inflow to the detention
pond. The vegetated shelf requirement has been replaced by the adjacent stormwater
wetland.
3. The proposed grassed swale will not be considered a pollutant removal swale, as the slopes
and flow rates will not allow a maximum velocity for the 10-year storm of one foot per second.
4. The Required Item Checklists for each BMP have been documented to indicate page and
sheet numbers where information is found.
Please contact me directly if you have additional questions regarding this application.
Sincerely,
```?NNUttt?bhi?i
CARO Z*/
v? . Q:••FE DiV6.
Stephen H. Blake, P.E. 2? 4Q SEA L •:
Director of Engineering 029585 -
Encl. Nj,•. •?c ?? • Q
Cc: Dan Gottlieb, NCMA
Jeffrey Lee, PBC&L
Walt Havener, LHPA
A RTIFEX inc
ENVIRONMENTAL DESIGN
2363 Blake Street, Sulte 202
Denver, CO 80205
[phone] phone
[phone] fax
www.artifexed.com
July 1, 2008
North Carolina Museum of Art-Museum Expansion Project
Stormwater Management Plan
Supplemental Application Materials
E t _
029505
Civil and Enviromiental Engineering Environmental Restoration Rehabilitation and Conservation Envimnmental and Urban Geography
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ART (? Denver, CO 80205
c t. 720 855 3721 t. 720 855 4210
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2363 Blake Street, Suite 202
ARTIFEXE 'F in c Denver, CO 80205
t. 720 855 3721 1. 720 855 4210
North Carolina Museum of Art
Museum Expansion
Site Area Tabulations
Existing Landcover Distribution
Landcover
IMPERVIOUS AREAS
WOODED AREAS
GARDEN/LANDSCAPE AREAS
MANAGED TURF AREAS
WATER
Total
Impervious Area
Proposed Landcover Distribution
Landcover
IMPERVIOUS AREAS
Existing Impervious Areas
Demolition Areas
Net Impervious Area Remaining
Proposed Buildings
Proposed Paving
Sill
WOODED AREAS Existing Wooded Areas
Demolition Wooded Areas
Proposed Wooded Areas
GARDEN/LANDSCAPE AREAS
Existing Garden/LS Areas
MANAGED TURF AREAS
WATER
Total Area
Net Impervious Area
Impervious Area %
7/1/2008
P-1 Basin P-2 Basin P-3 Basin P-4 B asin P-d to Pond Cover Total Cover

1.18 7.07 4.95 0.26 1.16 13.46 ac 28% 14.63 ac 26%
0.13 2.31 4.41 1.51 2.76 8.36 ac 18% 11.12 ac 20%
0.00 0.00 0.09 0.00 0.00 0.09 ac 0% 0.09 ac 0%a
0.41 5.16 11.67 7.14 4.29 24.38 ac 51% 28.67 ac 51%
0.00 0.00 0.00 1.35 0.00 1.35 ac 3% 1.35 ac 2%
1.73 ac 14.54 ac 21.12 ac 10.26 ac 8.21 ac
69% 49% 23% 3% 14%
Basin P-1 Basin P-2 Basin P-3 Basin P-4 Basin P

1.19 8.48 5.70 0.26 1.
1.18 7.07 4.95 0.26 1.
-0.02 -1.40 -1.16 0.00 0.
1.16 5.68 3.79 0.26 1.
0.00 1.01 0.84 0.00 0.
0.03 1.79 1.07 0.00 0.
0.03 2.80 1.91 0.00 0.
0.13 ac 2.09 ac 5.47 ac 1.51 ac 2.76
0.13 ac 2.31 4.41 ac 1.51 2.76
0.00 ac 1.57 1.00 ac 0.00 0.00
0.00 ac 1.35 2.06 ac 0.00 0.00
0.00 ac 0.00 0.65 ac 0.00 0.00
0.00 0.00 0.09 0.00 0.
0.00
0.40 0.00
3.90 0.56
9.26 0.00
7.72 0.
4.
0.00 0.07 0.04 0.77 0.
1.73 ac 14.54 ac 21.12 ac 10.26 ac 8.21
0.01 ac 1.40 ac 0.75 ac 0.00 ac 0.00
69% 58% 27% 3% 1d
47.64 ac 100% 55.85 ac 100%
Total Trib
to Pond
% Cover
Total %
Cover
15.63 ac 33% 16.79 ac 30%
13.46 ac 14.63 ac
-2.57 ac -2.57 ac
10.89 12.05
1.85 ac 1.85 ac
2.90 ac 2.90 ac
4.74 ac 4.74 ac
9.20 ac 19% 11.96 ac 20%
8.36 ac 11.12 ac
2.57 ac 2.57 ac
0.00 ac 3.41 ac
0.65 ac 1% 0.65 ac 1%
0.09 ac 0.09 ac
0.56 ac 0.56 ac
'- 21.28 ac 45% 25.57 ac 46%
0.87 ac 2% 0.87 ac 2%
47.64 ac 100% 55.85 ac 98%
- 2.17 ac 2.17 ac
33% 30%
2363 Blake Street,
CO 80205
A ` I n c t. 720 855 3721 f. 720 855 4210
ENVIRONMENTAL DESIGN www.artifexed.com
North Carolina Museum of Art
Museum Expansion
Hydrology, Proposed Pond
Museum Pond Proposed Grading
Pond Areas and Detention Volumes
Elev (ft) Area (sf) Add Area
392.9
393
394
395
396
397
398
398.7
Inner 398.7
Outer 398.7
399
399.75
400
401
402
403
estimated 403.2
0
4,709
12,285
17,166
22,304
28,904
35,046
35,439
52,664
52,664
57,795
61,669
61,926
67,985
73,173
80,820
86,596
Elevation
WQ Weir/Orifice 398.7
WQ Volume
Flood Control Weir 399.75 ft
Flood Control Volume
Main Pond Volume
Total
AR T I F E X Inc
ENVIRONMENTAL DESIGN
Vol (cf)
0
235
8,497
14,726
19,735
25,604
32,172
30,698
0
0
16,569
44,799
15,449
64,956
70,579
76,997
16,742
Death
1.05
Average
Vol (ac-ft) Cum Vol (cf) Cum Vol (ac-ft) Depth (ft)
0.00 0 0.00
0.01 235 0.01
0.20 8,732 0.20
0.34 23,458 0.54
0.45 43,193 0.99
0.59 68,797 1.58
0.74 . 100,968 2.32
0.70 131,667 3.02 3.8
0.00 131,667 3.02
0.00 131,667 3.02
0.38 148,236 3.40
1.03 193,035 4.43
0.35 208,484 4.79
1.49 273,440 6.28
1.62 344,019 7.90
1.77 421,015 9.67
0.38 437,757 10.05
Volume
61,368 cf 1.41 ac-ft
6.75 (maintain weir in existing configuration)
5.62 ac-ft
3.02 ac-ft
10.05 ac-ft
2363 Blake Street, Suite 202
Denver, CO 80205
t. 720 855 3721 f. 720 855 4210
www.artifexed.com
7/1/2008
North Carolina Museum of Art
Museum Expansion
Hydrology, Proposed Pond
Museum Pond Proposed Grading
Pond Areas and Detention Volumes
Main Pool Average North Forebay South Forebay Total Forebay South Wetland Pools Total Deep Pool
Elev (ft) Area (sf) Vol (cf) Vol (cf) Depth (ft) Area (sf) Vol (cf) Area (sf) Vol (cf) Vol (cf) Pools (sf) Vol (cf) Cum Vol (cf)
392.9 0
393 4709 235 235
394 12285 8,497 8,732
395 16440 14,363 23,095 600 300 126 63 363
396 20461 18,451 41,545 1303 952 540 333 1,648
397 24103 22,282 63,827 2389 1,846 1253 897 4,390 1159 580 580
398 27662 25,883 89,710 3093 2,741 1913 1,583 8,714 2771 1,965 2,545
398.7 28683 19,721 109,431 3.8
398.7
398.7 55955
399 56717
399.75 60827
400 61926
401 67985
402 73173
403 80820
403.2 86596
7/1/2008
2363 Blake Street, Suite 202
AR T I F E X i n c Denver, CO 80205
E N V I R O N M E N T A L D E S I G N t. 720 855 3721 f. 720 855 4210
www.artifexed.com
Nortth Carolina Museum of Art
Museum Expansion
Proposed Site Hydrology
Pond WQv Drawdown Calculations
Outlet Sizing
Summary for Pond 30P: Proposed Pond
Inflow = 0.00 ds @ 0.00 hrs, Volume= 0.000 of
Outflow = 0.51 ds @ 0.00 hrs, Volume= 1.358 af, Atten= 0%, Lag= 0.0 min
Primary = 0.51 ds @ 0.00 hrs, Volume= 1.358 of
Routing by Dyn-Stor-Ind method, Time Span= 0.00-120.00 hrs, dt= 0.01 hr's / 2
Starting Elev- 399.75' Surf.Area= 0 sf Storage= 187,006 d
Peak Bev= 399.75'@ 0.00 hrs Surf.Area= 0 sf Storage= 187,006 d
Flood Elev= 403.20' Surf.Area= 0 sf Storage= 421,683 d (234,677 d above start)
Plug-Flow detention time= (not calculated: initial storage e)cedes outflow)
Center-of-Mass det. time= (not calculated: no inflow)
Volume Invert Axeil.Storage Storage Description
#1 392.90' 431,728 d Custom Stage Data Listed below
Elevation Cum.Store
(feet) (cubic-feet)
392.90 0
393.00 235
394.00 8,934
395.00 23,458
396.00 43,193
397.00 68,797
398.00 100,968
398.70 125,638
399.00 142,207
399.75 187,006
400.00 202,455
401.00 267,411
402.00 337,990
403.00 414,986
403.50 431,728
Device Routing Invert Outlet Devices
#1 Primary 391.11' 36.0" x 84.0' long Culvert RCP, rounded edge headwall, Ke= 0.100
Outlet Invert= 389.69' S= 0.0169'f Cc= 0.900
n=0.011 Concrete pipe, straight & dean
#2 Device 1 398.70' 3.0" Vert. Orifice/Grate X 2.00 C= 0.600
#3 Device 1 399.74' 4.0' long Sharp-Crested Rectangular Weir X 4.00
2 End Contraction(s) 0.7' Crest Height
Primary OutRow Max=0.51 ds @ 0.00 hrs HW=399.75' (Free Discharge)
t--I--,Culvert (Passes 0.51 ds of 121.59 cfs potential flow)
2=Orifice/Grate (Orifice Controls 0.45 cfs @4.63 fps)
13=Sharp-(rested Rectangular Weir (Weir Controls 0.05 cfs @ 0.33 fps)
7/1/2008
I; 2363 Blake Street, Suite 202
A R T I F E X I n Denver, CO 80205
t. 720 855 3721 f. 720 855 4210
ENVIRONMENTAL DESIGN www.artifexed.com
North Carolina Museum of Art 7/1/2008
Museum Expansion
Proposed Site Hydrology
Pond WQv Drawdown Calculations
Outlet Sizing
Hydrograph for Pond 30P: Proposed Pond
Time Inflow Storage Elevation Primary
(hours) (cfs) (cubic-fleet) (feet) (cfs)
0.00 0.00 187,006 399.75 0.51
5.00 0.00 179,102 399.62 0.42
10.00 0.00 171,830 399.50 0.39
15.00 0.00 165,164 399.38 0.35
20.00 0.00 159,104 399.28 0.32
25.00 0.00 153,650 399.19 0.29
30.00 0.00 148,802 399.11 0.25
35.00 0.00 144,561 399.04 0.22
40.00 0.00 140,929 398.98 0.18
45.00 0.00 137,936 398.92 0.15
50.00 0.00 135,626 398.88 0.11
55.00 0.00 133,918 398.85 0.08
60.00 0.00 132,649 398.83 0.06
65.00 0.00 131,680 398.81 0.05
70.00 0.00 130,933 398.80 0.04
75.00 0.00 130,332 398.78 0.03
80.00 0.00 129,841 398.78 0.02
85.00 0.00 129,442 398.77 0.02
90.00 0.00 129,114 398.76 0.02
95.00 0.00 128,830 398.76 0.01
100.00 0.00 128,579 398.75 0.01
105.00 0.00 128,359 398.75 0.01
110.00 0.00 128,165 398.75 0.01
115.00 0.00 127,994 398.74 0.01
120.00 0.00 127,844 398.74 0.01
2363 Blake Street, Suite 202
Denver, CO 80205
A i n c t. 720 855 3721 f. 720 855 4210
ENVIRONMENTAL DESIGN www.artifexed.com
North Carolina Museum of Art
Museum Expansion
Hydrology, Flows at Proposed Pond
Storm
First Flush
1
Proposed Pond Conditions
Inflow Outflow
19 cfs 0.3 cfs
118 cfs 47 cfs
284 cfs 139 cfs
378 cfs 146 cfs
Existing Pond Conditions
Inflow Outflow
16 cfs 6 cfs
97 cfs 60 cfs
246 cfs 139 cfs
320 cfs 146 cfs
11/15/2006
V
2363 Blake Street, Suite 202
A R T I F E x i n c Denver, CO 80205
ENVIRONMENTAL DESIGN t. 7208553721 f. 7208554210
www.arUfexed.com
North Carolina Museum of Art
Museum Expansion
Hydrology, Proposed Pond
NCMA Expansion Stormwater Wetland Design
Area Plantings
Wetland Wetpond BMP
Total % Total % Total Plant Type Qty/ 200sf Quantity Type
Required WQ„o, Simple Method
Required min. WQ„o, 1" runoff, SCS
Total Area
Required Min. Area
Zones
Shallow Water
Shallow Land
Forebay
Deep Pool
61,600 cf
42,035 cf
27,909 sf 45% 33,760 sf
27,909 sf 66% 14,126 sf
12,063 sf 43%
10,267 sf 37%
3,823 sf 14%
1,756 sf 6%
27,909 sf 100%
55% 61,669 sf
34% 42,035 sf
Emergent 6 362 plugs
Total 565 varies
Herbaceous 6 308 4" container
Shrubs 4 205 1 gal container
Trees 1 51 2.5" dbh b-b
Total 105 varies
Floating 6 53 4" container
Submerged 6 53 4" container
Total Plantings 1032 varies
775 herbacious
6/30/2008
2363 Blake Street, Suite 202
A R T I F E X i n c Denver, CO 80205
t. 720 855 3721 f. 720 855 4210
ENVIRONMENTAL DESIGN www.arfrfexed.com
North Carolina Museum of Art
Museum Expansion
Water Quality Feature Sizing
Proposed Basin Hydrology
reatment Area
Basin P-1, P-2, P-3, P-4 Tributary to Pond
Total Area At := 47.64acre
Proposed Impervious Area
Percentage Impervious
Existing Impervious Area
Aimp := 16.21acre
l:= Aimp
At
Aeximp = 13.46acre
Permanent Undisturbed Open Space Anat := 9.20-acre
Permanent Managed Open Space Aman := 22.23-acre
Percentage Impervious lex := Aeximp
At
Water Quality Capture Volume Calculation
Q Reference:P:\NCMA_Expansion\Analysis\WaterQuality\WQ_RaleighData.xmcd(R)
Site Data
Water Quality Precipitation Depth PWQ := l in
Volumetric Runoff Coefficient Rv:= 0.05 + 0.009•I.100
RV = 0.356
Required WQ Volume
Required Volume for site with limp <15%
I = 34.026 %
Iex = 28.254 %
WQV := PWQ•RV-At WQV = 6.16 x 104cf
WQv= 1.414acft
WQvmin 0.2in•Al WQvmin = 3.46 x 104cf
WQvmin = 0.794acft
Aimp = 16.21 acre
7/1/2008
2363 Blake Street, Suite 202
Denver, CO 80205
l ' n c t 720.855.3721 f 720.855.4210
www.artifexed.oom
Fr?v[gOrlattrtT?l OESiGN
North Carolina Museum of Art
Museum Expansion
Water Quality Feature Sizing
Wet Detention Pond Sizing
Required Forebay Size
Required Wet Pond Volume, minimum
WQvwet = 2.942 x 104 cf
Required Permanent Pool Surface Area Mountain & Piedmont, 90% TSS Removal
Permanent Pool Depth
n := 0., cols(SADAQ,,) - 1
SARn := linte41P90, SADA9 ?? , I) SAn := SARn At
100
3 2.142 1.02
3.5 2.001 0.953
4 1.821 0.867
4.5 1.661 0.791
5 1.561 0.744
5.5 1.521 0.724
ool90 =
d 6 ft SAR
= 1.421 SA
= 0.677
p n n
6.5 1.301 0.62
7 1.201 0.572
7.5 1.161 0.553
8 1.121 0.534
8.5 1.021 0.486
9 0.981 0.467
Combined Wetland / Wetpond System
%wetland = 0.45 %wetpond = 0.55
depth := 3.8ft SAd := linterp(dpool90 SA, depth)
SARd := linterp(d
ool90 , SAR, depth
p ,
acre
Forebay Area
FA := 0.1-SA n
n
4444.17
4153.1
3778.48
3446.99
3239.47
3155.92
FA = 2948.4 ft2
n
2700.46
2492.94
2409.39
2325.84
2118.32
2034.77
SAd = 0.902 acre
7/1/2008
SAd = 3.928 x 104 ft2
SARd = 1.893
Wetpond Area Areafeq := %wetpond• SAd AreaCeq = 0.496 acre
AreaCeq = 2.161 x 104 ft2
Combined Wetland / Wetpond System
%wetland := .45 %wetpond := .55
Fv := 0.1 in• Aimp Fv = 5.884 x 103 cf
Fv = 0.135 acft
WQvwet := 0.5in•Aimp WQvwet = 0.675 acft
2383 Blake Street, Suite 202
AR T I F E X E Di n c Denver, CO 80205
t 720.855.3721 f 720.855.4210
www.artifexed.com
Er:VIR04MEN7.L DESIGN
North Carolina Museum of Art
Museum Expansion
Water Quality Feature Sizing
tormwater Wetland Sizing
Required wetland area
%wetland• WQv
Awetland
dwetland
Combined Wetland / Wetpond System
%wetland = 0.45 %wetpond = 0.55
dwetland 12in
Awetland = 0.636 acre
Awetland = 2.772 x 104 ft2
Deep Pools, 5-10% of wetland area, 18-36" depth
Apools = 0.1-Awetland
Apools = 0.064acre
Apools = 2.772 x 103 ft2
Forebay, 10% of wetland area, 18-36" depth
Aforebay 0.1 • Awetland Aforebay = 0.064 acre
`4forebay = 2.772 x 103 ft2
Low Marsh
Alowmarsh 0.4Awetland Alowmarsh = 0.255 acre
Alowmarsh = 1.109 x 104 ft2
High Marsh
Ahighmarsh 0.4Awetland Ahighmarsh = 0.255 acre
Ahighmarsh = 1.109 x 104 ft2
AR T I F E X' inc
ENVIH0NMEIN TA DESIGN
7/11/2008
2363 Blake Street, Suite 202
Denver, CO 80205
t 720.855.3721 f 720.855.4210
www.artifexed.com
North Carolina Museum of Art
Museum Expansion
Water Quality Feature Sizing
Nutrient Export Calculations
Nitrogen Management under Neuse Stormwater Rule (15A NCAC 213.0235)
Permanent Natural Open Space TNnat 'gnat TNcoeffo
Permanent Managed Open Space TNman Amari TNcoeff
1
Impervious Surfaces
Existing Impervious Reduction
TNimp = (Aimp)'TNcoeff2
TNeximp = (Aeximp)'TNcoeff2
Total
lb
TNnat = 5.52 -
yr
TNman = 26.676 lb
yr
lb
TNimp = 343.652 -
yr
TNeximp = 285.352 lb
Yr
TNt = TNnat + TNman + TNimp - TNeximp TNt = 90.496 lb
yr
TNt
Average for Site TNav _ TN = 1.9 lb
g At avg
acre•yr
Required
Target residential = 3.6 Ib/ac/yr (without development fees)
commercial = 3.6 Ib/ac/yr (without development fees)
Combination Wet Detention Pond / Created Wetland °/uwetland = 0.45 %wetpond = 0.55
TNRe ff := %wetland•TNRI + %wetpond TNR2 TNReff = 0.317
lb
TNred TNavg'TNReff TNred = 0.603 acre yr
Reduction neglecting existing impervious area credit
TNnat + TNman + TNimp
TNt lb
_ TN = 7.889
At avg acre•yr
d?- TNavg'TNReff TNred = 2.505 lb
b
acre-yr
7/1/2008
2363 Blake Street, Suite 202
tiR Denver, CO 80205
t 720.855.3721 f 720.855.4210
ARTIFEX ` n c
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fN IRt UUFN7AL OE31GN
Permit Number1012- t 3 O ^ V z
(to be provided by DWQ)
A ?
NCDENR
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WETLAND SUPPLEMENT
This form must be filled out, printed and submitted.
The Required Items Checklist (Part Ill) must be printed, filled out and submitted along with all the required information.
O?O? W A T?9?G
h ?
o
1. PROJECT MFOFOAATION
Project name North Carolina Museum of Art - Museum Expansion Project
Contact name Stephen H. Blake
Phone number [phone]
Date June 10, 2008
Drainage area number
II. DESIGN INEOUATION
Site Characteristics
Drainage area 2,075,198 fe
Impervious area 706,108 fe
Percent impervious 34.0%%
Design rainfall depth 1.0 inch
Peak Flow Calculations
Does this project require pre/post control of the 1-yr 24-hr peak
flow?
1-yr, 24-hr runoff depth
1-yr, 24-hr intensity
Pre-development 1-yr, 24-hr runoff
Post-development 1-yr, 24-hr runoff
Pre/Post 1-yr, 24-hr peak control
Storage Volume: Non-SR Waters
Design volume (temporary pool volume)
Depth of temporary pool/ponding depth (Dpw,,)
Drawdown time
Diameter of orifice
Coefficient of discharge (CD) used in orifice diameter
calculation
Driving head (Ho) used in the orifice diameter calculation
Storage Volume: SR Waters Parameters
1-yr, 24-hr depth
Pre-development 1-yr, 24-hr runoff
Post-development 1-yr, 24-hr runoff
Minimum volume required
Volume provided
Y (Y or N)
1.6 in
0.2 in/hr
26.5 ft3/sec
33.1 ft3/sec
6.6 ft3/sec
27,909 ft3 OK
12 in OK
5 days OK
3.00 in OK
0.65 (unitless)
0.333 ft OK
in
ft3
ft3
ft3
ft3
Form SW401 -Wetland-Rev. 1 Parts I and II. Project Design Summary, Page 1 of 3

Surface Areas of Wetland Zones
Surface Area of Entire Welland
Shallow Land
The shallow land percentage is:
Shallow Water
The shallow water percentage is:
Deep Pool
Forebay portion of deep pool (pretreatment)
The forebay surface area percentage is:
Non-forebay portion of deep pool
The non-forebay deep pool surface area percentage is:
Total of wetland zone areas
Add or subtract the following area from the zones
Topographic Zone Elevations
Temporary Pool
Shallow Land (top)
Permanent Pool
Shallow Water (top)
Deep Pool (top)
Most shallow point of deep pool's bottom
Deepest point of deep pool's bottom
Design must meet one of the following two options:
This design meets Option #1,
Deep pool is 611nches below SLWT, If yes:
SLWT (Seasonally Low Water Table)
This design meets Option #2,
Has a clay liner
If yes:
Depth of topsoil above clay liner
Topographic Zone Depths
Temporary Pool
Shallow Land
Permanent Pool
Shallow Water
Deep Pool (shallowest)
Deep Pool (deepest)
Planting Plan
Are cattails included in the planting plan?
Number of Plants in planting plan recommended:
Herbacious (41nch diameter)
Shrubs/small trees (1 gallon or larger)
Trees (1.5" dbh)
Number of Plants in planting plan provided (several species of
each plant type are recommended):
Herbacious (4inch diameter)
Shrubs/small trees (1 gallon or larger)
Trees (1.5" dbh)
Permit Number
(lo be provided by DWQ)
27,909 fe OK
9,646 ftz OK
35%
11,840 ftz Insufficient shallow water area.
A 1a_
3,652 fe OK
13%
2,771 ftz OK
10%
27,909 ft2 OK
0.00 fe
399.70 fmsl
398.70 fmsl
398.25 fmsl
396.75 fmsl
396.00 fmsl
Y (Y or N)
398.50 fmsl OK
N/A
N/A in
12 in OK
5.4 in OK
18 in OK
27 in OK
N (Y or N) OK
840
560
140
365 Higher density is recommended.
255 Higher density is recommended.
21 Higher density is recommended.
Form SW401-WeUand-Rev.1 Parts I and II. Project Design Summary. Page 2 of 3
Permit Number
(to be provided by DWQ)
Additional Information
Can the design volume be contained? Y (Y or N) OK
Does volume in excess of the design volume flow evenly N (Y or N) Excess volume must pass through filter.
distributed through a vegetated filter?
What is the length of the vegetated filter? It
Does the design use a level spreader to evenly distribute flow? N (Y or N) Show how flow is evenly distributed.
Are calculations for supporting the design volume provided in the Y (Y or N) OK
application?
Is BMP sized to handle all runoff from ultimate build-out? Y (Y or N) OK
Is the BMP located in a recorded drainage easement with a Y (Y or N) OK
recorded access easement to a public Right of Way (ROW)?
The length to width ratio is: 6.9 :1 OK
Approximate wetland length 296.0 It
Approximate wetland width 43.0 ft

Approximate surface area using length and width provided
12,728 ftz This approx. surface area is within this number of square
feet of the entire wetland surface area reported above:
Will the wetland be stabilized within 14 days of construction? Y (Y or N) OK
Form SW401-Wetland-Rev.1 Parts I and II. Project Design Summary, Page 3 of 3
Permit No. 06-1302
(to be provided by DWQ)
Ill. REWIRED ITEMS CiC
Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below. If a
requirement has not been met, attach justification.
Initials Pagel Plan
Sheet No.
SP01
Draina a Schematics Post Develo ment
SW106
SW104
Plans (1" - 50' or larger) of the entire site showing:
- Design at ultimate build-out,
- Off-site drainage (if applicable),
- Delineated drainage basins (include Rational C coefficient per basin),
- Wetland dimensions (and length to width ratio),
- Pretreatment system,
- Maintenance access,
- Recorded drainage easement and public right of way (ROW),
- Overflow device, and
- Boundaries of drainage easement.
?lOc? 2. Plan details (1" = 50' or larger) for the wetland showing:
Sw1 os - Wetland dimensions (and length to width ratio)
- Pretreatment system,
- Maintenance access,
- Recorded drainage easement and public right of way (ROW),
- Design at ultimate build-out,
- Off-site drainage (if applicable),
Sw104 - Overflow device, and
- Boundaries of drainage easement.
Sk_ SW1 os 3. Section view of the wetland 0" = 20' or larger) showing:
- Side slopes, 3:1 or lower
- Wetland layers
All wetlands: Shallow land depth, shallow water depth, deep pool depth
Option 1, no clay liner: SLWT depth
Option 2, clay liner: Depth of topsoil on top of liner, liner specifications
_S106 SW105 4. A detailed planting plan (1" = 20' or larger) prepared by a qualified individual showing:
- A variety of suitable species (not including cattails),
- Sizes, spacing and locations of plantings,
- Total quantity of each type of plant specified,
- A planting detail,
- The source nursery for the plants, and
- Fertilizer and watering requirements to establish vegetation.
IStormwater Wetland Construction 5. A construction sequence that shows how the wetland will be protected from sediment until the entire
drainage area is stabilized.
A endix C 6. The supporting calculations (including drawdown calculations).
7. A copy of the signed and notarized inspection and maintenance agreement.
ISee Attached Sheet Item #3 8. A copy of the deed restriction.
SW401-Wetland-Rev.1 Part III, page 1 of 1
Permit
(to be provided by DWQ)
OF W ATF9
A O O? O?
?? r
HWENR °
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
401 CERTIFICATION APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form must be filled out, printed and submitted.
The Required gems Checklist (Part 111) must be printed, filled out and submitted along with all of the required information.
I. PROJECT INFORMATION
Project name North Carolina Museum of Art - Museum Expansion Project
Contact person Stephen H. Blake
Phone number [phone]
Date 3/24/2008
Drainage area number
h. DEMN INFORIr1AT101
Site Characteristics
Drainage area 2,075,198 fe
Impervious area 706,108 fe
% impervious 34.02605438 %
Design rainfall depth 1.0 in
Storage Volume: Non-SR Waters
Minimum volume required 29,420 fe
Volume provided 244,807 fe
Storage Volume: SR Waters
1-yr, 24-hr runoff depth in
Pre-development 1-yr, 24-hr runoff fe
Post-development 1-yr, 24-hr runoff ft'
Minimum volume required fe
Volume provided fe
Peak Flow Calculations
Is pre/post control of the 1-yr 24-hr peak flow required? Y (Y or N)
1-yr, 24-hr rainfall depth 1.6 in
Rational C, pre-development (unifless)
Rational C, post-development (unifless)
Rainfall intensity: 1-yr, 24-hr storm 0.2 in/hr
Pre-development 1-yr, 24-hr peak flow 26.5 fe/sec
Post-development 1-yr, 24-hr peak flow 33.1 fe/sec
Pre/Post 1-yr, 24-hr peak flow control 6.6 fe/sec
Basin Elevations
Basin bottom elevation 392.90 It
Sediment cleanout elevation 393.90 It
Permanent pool elevation 398.70 It
Temporary pool elevation 399.75 ft
Volume and Surface Area Calculations
SAIDA ratio 0.02 (unifless)
Permanent pool, surface area required 23,090 fe
Permanent pool, surface area provided 28,683 fe
Permanent pool volume 109,431 fe
Average depth for SAIDA tables 3.815186696 It
Forebay volume 12,506 fe
Forebay % of permanent pool volume 11 %
Temporary pool, surface area provided 61,669 fe
OK
OK
Must be approx. 20%, Adjust pond dimensions
Form SW401-Wet Detention Basin-Rev.2 Parts I. & II. Design Summary, Page 1 of 2
Permit
(to be provided by DWQ)
11. DESGM DWOM710N
Drawdown Calculations
Treatment volume drawdown time 5 days OK
Treatment volume discharge rate 0.51 ft'/s
Pre-development 1-yr, 24-hr discharge 12.47 Fels OK
Post-development 1-yr, 24-hr discharge 0.42 g3 /s OK
Additional Information
Diameter of orifice 3.00 in
Design TSS removal 90 %
Basin side slopes 3 :1 OK
Vegetated shelf slope 14 :1 OK
Vegetated shelf width 14 It OK
Length of flowpath to width ratio 3.818181818 :1 OK
Length to width ratio 2.045454545 :1 OK
Trash rack for overflow & orifice? Y (Y or N) OK
Freeboard provided 1 It OK
Vegetated filter provided? N (Y or N) Design must be based on 90% TSS removal
Recorded drainage easement provided? Y (Y or N) OK
Capures all runoff at ultimate build-out? Y (Y or N) OK
Drain mechanism for maintenance or emergencies Ex. Drain
Form SW401-Wet Detention Basin-Rev.2 Parts I. & II. Design Summary, Page 2 of 2
Permit No. 06-1302
(to be provided by DWQ)

Please indicate the page or plan sheet numbers where the supporting documentation can be found. An incomplete submittal package will
result in a request for additional information. This will delay final review and approval of the project. Initial in the space provided to
indicate the following design requirements have been met. If the applicant has designated an agent, the agent may initial below, If a
requirement has not been met, attach justification.
Pagel Plan
Initials Sheet No.
522.oAt 1. Plans (1" - 50' or larger) of the entire site showing:
SP01 - Design at ultimate build-out,
Off-site drainage (if applicable),
Delineated drainage basins (include Rational C coefficient per basin),
Drainage Schematics Post Development _ Basin dimensions,
Pretreatment system,
High flow bypass system,
Maintenance access,
Recorded drainage easement and public right of way (ROW),
Overflow device, and
SW104 Boundaries of drainage easement.
54 2. Partial plan (1" = 30' or larger) and details for the wet detention basin showing:
Outlet structure with trash rack or similar,
SW104 Maintenance access,
SW101 Permanent pool dimensions,
Forebay and main pond with hardened emergency spillway,
- Basin cross-section,
- Vegetation specification for planting shelf, and
- Filter strip.
"? SW106 3. Section view of the dry detention basin (1" = 20' or larger) showing:
Side slopes, 3:1 or lower,
Pretreatment and treatment areas, and
Inlet and outlet structures.
?V N)A 4. If the basin is used for sediment and erosion control during construction, clean out of the basin is specified
on the plans prior to use as a wet detention basin.
Appendix C 5. A table of elevations, areas, incremental volumes & accumulated volumes for overall pond and for forebay,
to verify volume provided.
6. An assurance that the installed system will meet design specifications upon initial operation once the
project is complete and the entire drainage area is stabilized.
IStormwater Wetland Construction 7. A construction sequence that shows how the wet detention basin will be protected from sediment until the
entire drainage area is stabilized.
A endix C 8
Th
ti
l
l
i
.
e suppor
ng ca
cu
at
ons.
9. A copy of the signed and notarized inspection and maintenance (I&M) agreement.
See Attached Sheet Item #3 10. A copy of the deed restriction.
Form SW401Met Detention Basin-Rev. 1 Part III. Required Items Checklist, Page 1 of 1
A x .
RTIFEXd; are inc
ENVIRONMENTAL DESIGN
2363 Blake Street, Suite 202
Denver, CO 80205
[phone] phone
[phone] fax
www.artifexed.com
July 1, 2008
Permit Attachment
Wet Detention Basin and Grassed Swale Supplements - Additional Explanations
1. The existing pond has been rehabilitated to maximize the storage for suspended sediment by
providing three distinct forebays at the entrance of all stormwater outfalls to the pond. Given the
existing pond's large initial wet pool, however, a maximum ratio of forebay volume to wet pool volume
of 8% is provided. It was determined preferable to retain the wet pool size, even though it is significantly
larger than required for the site's water quality requirements. The required ratio of total sediment
storage to site impervious area has been provided in the proposed design.
2. The existing pond configuration is relatively rectangular. With grading of the pond margins and
aquatic shelf, and the effects of vegetation around the pond perimeter, a length to width ratio of 2.5:1
has been provided in the proposed design. Relocation of the outfall may help improve this ratio for the
majority of the site's stormwater runoff, but was not deemed feasible within this project due to cost
considerations.
3. The property is owned in its entirety by the State of North Carolina. The portion of the property in
question is part of the North Carolina Museum of Art Park, and will not be sold or subdivided. The area
where the BMPs are to be created is currently dedicated to Stormwater Management, with existing
storm sewers, inlets and a detention pond. Access is provided from the public right of way along Blue
Ridge Road, along the site roads and concrete path, which also serves as the pond embankment and
access, and provides access to the existing electrical power transmission towers.
Stormwater Wetland Inspection and Maintenance Agreement
I will keep a maintenance record on this BMP. This maintenance record will be kept in a
log in a known set location. Any deficient BMP elements noted in the inspection will be
corrected, repaired or replaced immediately. These deficiencies can affect the integrity
of structures, safety of the public, and the removal efficiency of the BMP.
Important maintenance procedures:
- Immediately after the stormwater wetland is established, the wetland plants will
be watered twice weekly if needed until the plants become established
(commonly six weeks).
- No portion of the stormwater wetland will be fertilized after the first initial
fertilization that is required to establish the wetland plants.
- Stable groundcover will be maintained in the drainage area to reduce the
sediment load to the wet detention basin.
- Once a year, a dam safety expert will inspect the embankment.
After the wet detention pond is established, I will inspect it once a month and within 24
hours after every storm event greater than 1.0 inches (or 1.5 inches if in a Coastal
County). Records of inspection and maintenance will be kept in a known set location
and will be available upon request.
Inspection activities shall be performed as follows. Any problems that are found shall
be repaired immediately.
BMP element: Potential problem: How I will remediate the problem:
The entire BMP Trash/debris is resent. Remove the trash/debris.
The perimeter of the Areas of bare soil and/or Regrade the soil if necessary to
wetland erosive gullies have formed. remove the gully, and then plant a
ground cover and water until it is
established. Provide lime and a
one-time fertilizer application.
Vegetation is too short or too Maintain vegetation at a height of
long. approximately six inches.
The inlet device: pipe or The pipe is clogged (if Unclog the pipe. Dispose of the
Swale applicable). sediment off-site.
The pipe is cracked or Replace the pipe.
otherwise damaged (if
applicable).
Erosion is occurring in the Regrade the Swale if necessary to
swale (if applicable). smooth it over and provide erosion
control devices such as reinforced
turf matting or riprap to avoid
future problems with erosion.
BMP element: Potential problem: How I will remediate the problem:
The forebay Sediment has accumulated in Search for the source of the
the forebay to a depth that sediment and remedy the problem if
inhibits the forebay from possible. Remove the sediment and
functioning well. dispose of it in a location where it
will not cause impacts to streams or
the BMP.
Erosion has occurred. Provide additional erosion
protection such as reinforced turf
matting or riprap if needed to
Prevent future erosion problems.
Weeds are present. Remove the weeds, preferably by
hand. If a pesticide is used, wipe it
on the plants rather than spraying.
The deep pool, shallow Algal growth covers over Consult a professional to remove
water and shallow land 50% of the deep pool and and control the algal growth.
areas shallow water areas.
Cattails, phragmites or other Remove the plants by wiping them
invasive plants cover 50% of with pesticide (do not spray) -
the deep pool and shallow consult a professional.
water areas.
Shallow land remains flooded Unclog the outlet device
more than 5 days after a immediately.
storm event.
Plants are dead, diseased or Determine the source of the
dying. problem: soils, hydrology, disease,
etc. Remedy the problem and
replace plants. Provide a one-time
fertilizer application to establish the
ground cover if a soil test indicates
it is necessary.
Best professional practices Prune according to best professional
show that pruning is needed practices.
to maintain optimal plant
health.
Sediment has accumulated Search for the source of the
and reduced the depth to 75% sediment and remedy the problem if
of the original design depth possible. Remove the sediment and
of the deep pools (see dispose of it in a location where it
diagram below). will not cause impacts to streams or
the BMP.
BMP element: Potential problem: How I will remediate the problem:
The embankment A tree has started to grow on Consult a dam safety specialist to
the embankment. remove the tree.
An annual inspection by an Make all needed repairs.
appropriate professional
shows that the embankment
needs repair.
Evidence of muskrat or Use traps to remove muskrats and
beaver activity is present. consult a professional to remove
beavers.
The micropool Sediment has accumulated Search for the source of the
and reduced the depth to 75% sediment and remedy the problem if
of the original design depth possible. Remove the sediment and
(see diagram below). dispose of it in a location where it
will not cause impacts to streams or
the BMP.
Plants are growing in the Remove the plants, preferably by
micropool. hand. If a pesticide is used, wipe it
on the plants rather than spraying.
The outlet device Clogging has occurred. Clean out the outlet device. Dispose
of the sediment off-site.
The outlet device is damaged Repair or replace the outlet device.
The receiving water Erosion or other signs of Contact the NC Division of Water
damage have occurred at the Quality 401 Oversight Unit at 919-
outlet. 733-1786.
Permit No.
State of North Carolina
Department of Environment and Natural Resources
Division of Water Quality
(to be provided by DWQ)
STORMWATER MANAGEMENT PERMIT APPLICATION FORM
WET DETENTION BASIN SUPPLEMENT
This form may be photocopied for use as an original
DWQ Stormwater Management Plan Review:
A complete stormwater management plan submittal includes an application form, a wet detention basin
supplement for each basin, design calculations, and plans and specifications showing all basin and outlet
structure details.
1. PROJECT INFORMATION
Project Name: North Carolina Museum of Art - Museum Expansion Project
Contact Person: Stephen H. Blake Phone Number: ( 720 855-3721
For projects with multiple basins, specify which basin this worksheet applies to:
elevations
Basin Bottom Elevation 392.90 ft.
Permanent Pool Elevation 398.70 ft.
Temporary Pool Elevation 399.74 ft.
areas
Permanent Pool Surface Area 52,664sq. ft
Drainage Area 47.64 ac.
Impervious Area 16.21 ac.
(floor of the basin)
(elevation of the orifice)
(elevation of the discharge structure overflow)
(water surface area at the orifice elevation)
(on-site and off-site drainage to the basin)
(on-site and off-site drainage to the basin)
volumes
Permanent Pool Volume 131,667 cu. ft. (combined volume of main basin and forebay)
Temporary Pool Volume 61,368 cu. ft. (volume detained above the permanent pool)
Forebay Volume 8,714 cu. ft. (approximately 20% of total volume)
Other parameters
SAMA1
Diameter of Orifice
Design Rainfall
Design TSS Removal 2
1.893 (90%) (surface area to drainage area ratio from DWQ table)
3
in. (2 to 5 day temporary pool draw-down required)
8 in.
90 %
Form SWU-102 Rev 3.99 Page 1 of 4
(minimum 85% required)
JUL 2 Mg
DEW Sj pSERBRW
WE11 A1?
Footnotes:
When using the Division SA/DA tables, the correct SA/DA ratio fur permanent pool sizing should be computed based upon the
actual impervious % and permanent pool depth. Linear interpolation should be employed to determine the correct value for non-
standard table entries.
In the 20 coastal counties, the requirement for a vegetative filter may be waived if the wet detention basin is designed to provide
901/6 TSS removal. The NCDENR BW manual provides design tables for both 855/6 TSS removal and 90% TSS removal.
11. REQUIRED ITEMS CHECKLIST
The following checklist outlines design requirements per the Stormwater Best Management Practices Manual
(N.C. Department of Environment, Health and Natural Resources, February 1999) and Administrative Code
Section: 15 A NCAC 2H. 1008.
Initial in the space provided to indicate the following design requirements have been met and supporting
documentation is attached. If the applicant has designated an agent in the Stormwater Management Permit
Application Form, the agent may initial below. If a requirement has not been met, attach justification.
Appl' is Initials
a. The permanent pool depth is between 3 and 6 feet (required minimum of 3 feet).
b. The forebay volume is approximately equal to 20% of the basin volume. -?K
c. The temporary pool controls runoff from the design storm event.
d The temporary pool draws down in 2 to 5 days.
e. If required, a 30-foot vegetative filter is provided at the outlet (include non-erosive flow
calculations)
y'1'f The basin length to width ratio is greater than 3:1. *
g. The basin side slopes above the permanent pool are no steeper than 3:1.
h. A submerged and vegetated perimeter shelf with a slope of 6:1 or less (show detail).
i. Vegetative cover above the permanent pool elevation is specified.
J. A trash rack or similar device is provided for both the overflow and orifice.
yL A recorded drainage easement is provided for each basin including access to nearest right-
of-way. *,
1. If the basin is used for sediment and erosion control during construction, clean out of the
basin is specified prior to use as a wet detention basin.
in. A mechanism is specified which will drain the basin for maintenance or an emergency.

III. WET DETENTION BASIN OPERATION AND MAINTENANCE AGREEMENT
The vet detention basin system is defined as the wet detention basin, pretreatment including forebays and the
vegetated filter if one is provided.
This system (check one) 0 does vedoes not incorporate a vegetated filter at the outlet.
This system (check one) edoes 0 does not incorporate pretreatment other than a forebay.
Form SWU-102 Rev 3.99 Page 2 of 4
Maintenance activities shall be performed as follows:
1. After every significant runoff producing rainfall event and at least monthly:
a. Inspect the wet detention 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 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 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 2.8 feet in the main pond, the sediment shall be removed.
When the permanent pool depth reads 2.8 feet in the forebay, the sediment shall be removed.
BASIN DIAGRAM
(fill in the blanks)
Permanent Pool Elevation 398.7
Sediment Re oval El. 395.9 75°/?
_ _ _ _ _ _ _ _ _ _ _ _ _ _ Sediment Removal Elevation 395.9 75°/
--------------
Bottom Ele ation 395 25% "----------------------------------------- /j
------
Bottom Elevation 395 25
FOREBAY MAIN POND
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.
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.
Form SWU-102 Rev 3.99 Page 3 of 4
.
7. All components of the wet detention basin system shall be maintained in good working order.
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: 7ARIEL- GcrrfLlEC6
Title: ?? t e Cvr o F (?? lunh. a, q es i qh
Signature:
Date:
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.
a Notary Public for the State of AlOr-tk 6&,m 6t ,
County of yJ a? , do hereby certify that b" (
personally appeared before me this $ day of r, 7waf(, and acknowledge the due
execution of the forgoing wet detention basin maintenance requirements. Witness my hand and official seal,
SEAL
My commission expires R L25120 ( 0
Form SWU-102 Rev 3.99 Page 4 of 4
U.S. ARMY CORPS OF ENGINEERS
Wilmington District
Action ID: 2008-01423 County: N\'ake
NO DEPARTMEN'T' OF THE ARMY AUTHOI;UZATION REQUIRED
Property
Owner North Carolina Museum of Art
Attn: Dan Gottlieb
Address Raleigh, NC 27607
Property
Owner
Add
Telephone Nuniber_919-839-6262 Telephone Number.
Size and Location of Property (waterbodv, Hi!hway name/number, town, etc.): The North
Carolina Museum of Art, museum expansion project is 165 acres of land located in the northeast
quadrant of the intersection of Wade Avenue and Blue Ridge Road, in Raleigh, Wake County,
North Carolina.
Description of Activity: The project includes the expansion of the existing museum buildings,
construction of new exhibition space and revised site parking and roadway configuration on upland areas
of the property. Additionally, the project includes improvements to thb. existing stormwater retention
pond. All proposed work will be constructed in upland areas or on the non jurisdictional storinwater
retention pond.
Your work as proposed does not require Department of the Army authorization for the following reason(s):
X
This Department of the Army determination does not relieve the permittee of the responsibility to
obtain any other required Federal, State, or local approvals/permits. The permittee may need to
contact appropriate State and local agencies before beginning work.
Anv chap ;es in the above described work must be coordinated with the Corps of Engineers prior to
commencement. If you have any questions regarding the Corps of Engineers regulatory program,
please contact _ Crystal Amschler at telephone number (919) 55,- 4884 extension 27
Regulatory Project Manager Signature
Date June 5, 2008 Expiration Date N/A
There are no jurisdictional waters or wetlands within the boundaries of the property.
The proposed project does not impact jurisdictional waters or wetlands.
The proposed project is exempt from Department of the Army regulation.
(Specify)
SURVEY PLATS, FIELD SKETCH, WETLAND DELINEATION FORM, ETC., MUST BE ATTACHED
IF REQUIRED OR AVAILABLE.
_ U AR T I F ExEDinc
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Drainage 0
Basin Designation
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ma er ?? Proposed Storm Sewer Line
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l Point of Analysis
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IMPERVIOUS AREA= 5.79 AC WOODED AREA- 1.51 AC S STATE PLANE
o 61'' ear +i A4 Al WOODED AREA- 3.41 AC \ GARDENALANDSCAPE AREA- 0.00 AC
oeo. 9 \ \ ?\\ GARDEN/LANDSCAPE AREA- 1.77 AC \\\ MANAGED TURF AREA- 7.72 AC DATUM:
M
I ANAGED TURF AREA- 9.95 AC \ ?' WATER AREA=. 0.77 AC
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WEIGHTED CURVE NUMBER- 72
NORTH SCALE:
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NOTES AND REVISIONS
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Basin Boundary
/ \ J I I III ?? ?? % ;? Dranage
P 1
Basin Designation
Proposed Storm Sewer Line
I
4
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Existing Storm Sewer Line
53
Point of Analysis
Proposed Major Contour
POA D?
Proposed Minor Contour
Existing major contour
Existing Minor Contour -
Pond Tributary Basin
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..TOTAL AREA- 10.26 AC
?? A y -IMPERVIOUS AREA- 0.26 AC y/ A COORD SYS:
-TOTAL AREA- 21.12 AC
1 1 A IMPERVIOUS AREA= 5.79 AC WOODED AREA- 1.51 AC PLANE
A V ??
\ \ STATE
`WOODED AREA= 3.41 ACS GARDEN/LANDSCAPE AREA= 0.00 AC-?? --??
AREA- 1.77 AC MANAGED TURF AREA= 7.72 AC DATUM:
V?v MANAGED TURF AREA- 9.95 AC WATER AREA= 0.77 AC
NAD
WATER AREA= 0.20 AC ?'?_???WEIGHTED CURVE NUMBER= 71 83
a ?'"k A
Lli ! ?? "?,A?I A WEIGHTED OURVE NUMBE NORTH SCAL
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DATE: 12_.01.2006
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DENR•WATER QUAUTY
WETLANDS AND STORMWATER BRANCH
DRAWING NUMBER
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