SW4240401_Supplement-EZ Form_20240605

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SUPPLEMENT-EZ COVER PAGE
FORMS LOADED
PROJECT INFORMATION
—. — — — _<
1 Project Name Whitehall Village South
2 Project Area(ac) 6.874
I.
3 Coastal Wetland Area(ac) 0
r—4 Surface Water Area ac 0
5 Is this ro'ect Hi h or Low Density? High
6 Does this project use an off-site SCM? No ~,
COMPLIANCE WITH 02H.1003(4)
7 Width of vegetated setbacks provided(feet) 0
8 Will the vegetated setback remain vegetated? N/A
9 If BUA is proposed in the setback,does it meet NCAC 02H.1003(4)(c-d)? N/A
10 10 Is streambank stabilization proposed on this project? No
NUMBER AND TYPE OF SCMs: -
I 11 Infiltration System
0
12 Bioretention Cell 2
13 Wet Pond 0 I
14 Stormwater Wetland - 0
15 Permeable Pavement 0
I 16 Sand Filter 0
17 Rainwater Harvesting(RWH) 0 v�
18 Green Roof 0
19 Level Spreader-Filter Strip(LS-FS) 0 �!
20 Disconnected Impervious Surface(DIS) 0
! 21 Treatment Swale 0
22 Dry Pond
d 23 StormFilter 0
I 24 Silva Cell _ 0
25 Bayfilter 0
126 Filterra 0 -A
FORMS LOADED
,DESIGNER CERTIFICATION
27 Name and Title: Charles P.Truby,Jr.PE PLS Presidentv___
28 Organization: CPT Engineering and Surveying,Inc.
29 Street address: —__-4400 Tyning Street _ �a
30 City,State,Zip: High Point,NC,27265 __
31 Phone number(s): ,[phone] x 304
[e-mail] �
32 Email:
Certification Statement:
I certify,under penalty of law that this Supplement-EZ form and all supporting information were prepared under my direction or supervision;that the
information provided in the form is,to the best of my knowledge and belief,true,accurate,and complete;and that the engineering plans,specifications,
operation and maintenance agreements and other supporting information are consistent with the information provided here.
Designer
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Seal Date

DRAINAGE AREAS
1 Is this a high densi project? _ Yes — 7
j 2 If so, number of drainage areas/SCMs 2
3 Does this project have low density areas? No
4 If so, number of low density drainage areas 0
1 Is all/part of this project subject to previous rule
5 versions? i No
FORMS LOADED
DRAINAGE AREA INFORMATION Entire Site_` jr:_-__
- 9 �r_ 2
- -- L B ._.. �,v-_-�.. o-c _�.. .�
4 Type of SCM Bio-cell �F Bio-cell � Bio-cell5 Total drainage area (sq ft) if-��243936� 67953.6 175982.4
6 Onsite drainage area (sq ft) j 243936 67953.6 I 175982.4
7 Offsite drainage area (sq ft) 0 0 + 0 I
8 Total BUA in project(sq ft) 144184 sf 40511 sf 1 103673 sf !
New BUA on subdivided lots (subject to permitting)
y
9 (sq ft) L sf sf I _ sf
New BUA not on subdivided lots (subject to ! l
10 permitting) (sf) i _ sf sf sf
11 Offsite BUA(sq ft) ' sf I sf sf
l ;
12 Breakdown of new BUA not on subdivided lots:
- Parking (sq ft) 470 sf 470 sf sf _
-Sidewalk(sq ft) 7805 sf 1704 sf . 6101 sf
- Roof(sq ft) 83933 sf 23777 sf _ 60156 sf i
- Roadway(sq ft) 35685 sf 9749 sf 1 2593E sf
- Future(sq ft) sf �- sf sf
V
-Other, please specify in the comment box below I a
(sq ft) j sf j sf ;: sf i
New infiltrating permeable pavement on subdivided ti '
13 lots(sq ft) sf sf I sf 1
New infiltrating permeable pavement not on
14 subdivided lots (sq ft) sf_ sf sf
Existing BUA that will remain (not subject to H l
15 permitting)(sq ft) i sf sf sf
16 Existing BUA that is alread permitted s• ft ( sf sf sf
17 Existing BUA that will be removed (sq ft) sf sf ! sf
18 Percent BUA 59% L 60% ; 59%
19 Design storm (inches 1.0 in 1.0 in 1.0 in
II
20 Design volume of SCM (cu ft) ! 3341 cf ! 8506 cf
21 Calculation method for design volume SCS SCSI SCS
ADDITIONAL INFORMATION
Please use this space to provide any additional information about the
22 drainage area(s):

BIORETENTION CELL
1 Drainage area number 1 -1 r_ 2
' 2 Minimum required_treatment volume(cu ft),____ 3341 cf 8506 cf
'GENERAL MDC FROM 02H.1050 _ �3
3 Is the SCM sized to treat the SW from a surces
Yes
Yes
ll
i 4 Is the SCM located away from contaminatedsoi s'at build out? Yes Yes ti
5 What are the side slopes of the SCM(H:V)? 3:1 ; 1:1
i 6 Does the SCM have retaining walls,gabion walls or other engineered
side slopes? Yes 1 Yes
Are the inlets, outlets, and receiving stream protected from erosion 1
7
' (10-year
storm)? Yes Yes
8 Is there an overflow or bypass for inflow volume in excess of the
design volume? Yesi' Yes
j 9 What is the method for dewatering the SCM for maintenance? Drawdown Orifice I:, Drawdown Orifice
10 If applicable,will the SCM be cleaned out after construction? Yes ! Yes
r 11 Does the maintenance access comply with General MDC(8)? Yes 'F No
_
12 Does the drainage easement comply with General MDC(9)? Yes Yes
13 If the SCM is on a single family lot, does(will?)the plat comply with
General MDC(10)? N/A N/A
1 14 Is there an O&M Agreement that complies with General MDC 11 ? Yes 9 P ( )• Yes
15 Is there an O&M Plan that complies with General MDC(12)? — Yes 1 Yes
1 16 Does the SCM follow the device specific MDC? _ _ Yes Yes
I 17 Was the SCM designed by an NC licensed professional? Yes �� Yes ��
BIORETENTION CELL MDC FROM 02H.1052
1 18 SHWT elevation(fmsl) 973.00 i 969.80
19 Bottom of the bioretention cell(fmsl) 976.72 3 968.70
20 Ponding depth of the design storm(inches) 12 in 12 in
1 21 Surface area of the bioretention cell(square feet) 3459 sf i 8534 sf a
22 Design volume of SCM(Cu ft) 3341 cf 8506 cf •
23 Is the bioretention cell used for peak attenuation? Yes Yes
24 Depth of peak attenuation over planting surface(in) 25 in I 26 in --
25 Height of peak attenuation outlet above the planting surface(in) 30 in 1 30 in, i
26 Infiltration rate of the in situ soil(inch/hour) NA i NA �i
27 Diameter of the underdrain pipes(if applicable) 6 in i 6 in f
1 28 Does the design include Internal Water Storage(IWS)? Yes '' Yes J
29 if so,elevation of the top of the IWS(fmsl) 979.5 _ ! 971.5
30 Elevation of the planting surface(fmsl) 981 T 973 -1'
j What type of vegetation will be planted? (grass,trees/shrubs,other)? Grass Grass
1 32 Media depth(inches) 30 in t1 Y 30 in
33 Percentage of medium to coarse washed sand by volume 75-85% i 75-85% 1
34 Percentage of fines(silt and clay)by volume _ 8-15% 8-15%
35 Percentage of organic matter by volume 5-15% 5-15%
36 Type of organic material Pine Bark • Pine Bark
37 Phosphorus Index(P-Index)of media(unitless) 50 ' 50 _ J
38 Will compaction be avoided during construction? Yes Yes
39 Will cell be maintained to a one inch/hour standard? Yes Yes
' 40 Depth of mulch, if applicable(inches) — in in
41 Type of mulch,if applicable 0 0
42 How many clean out pipes are being installed? 5 10
43 Type of pretreatment that will be used: Rip-rap Forebay Rip-rap orebay 1
ADDITIONAL INFORMATION —_---,I _--.-_--
44 Please use this space to provide any additional information about the
bioretention cell(s):
Proposed Bio-Cell#2 will require impermeable geo-membrane liner to top of 1i'
sod(973.0)
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*retention 1= 12:15 PM 4/3/2024