SW3230701_Supplement-EZ Form_20240621

SUPPLEMENT-EZ COVER PAGE
FORMS LOADED
PROJECT INFORMATION _
1 Project Name Stewart's Grove
2 Project Area(a ) _ 17.67
3 Coastal Wetland Area(ac) 0
4 Surface Water Area(ac) _ 0.74
5 Is this project High or Low Density? High
6 Does this project use an off-site SCM? I
No
COMPLIANCE WITH 02H.1003(4)
7 Width of vegetated setbacks provided(feet) 50'
8 Will the vegetated setback remain vegetated?
9 �If BUA is proposed in the setback,does it meet NCAC 02H.1003(4)(c-d)? N/A
L10 Is streambank stabilization proposed on this project? Yes
No
NUMBER AND TYPE OF SCMs:
11 Infiltration System 0
12 Bioretention Cell 0
13 Wet Pond 0
14 iStormwater Wetland 0
15 Permeable Pavement 0
16 Sand Filter _ 1 2
17 Rainwater Harvesting(RWH) —I 0
18 Green Roof I 0
19 ,Level Spreader-Filter Strip(LS-FS)_ 0
20 (Disconnected Impervious Surface(DIS) _ —_ _—I 0
21 'Treatment Swale I 0
_22 Dry Pond —I 0
23 StormFilter _ i 0
24_:Silva Cell I 0
25 Bayfilter I 0
26 Filterra i 0
FORMS LOADED
DESIGNER CERTIFICATION
27 Name and Title: Nestor Hemandez,PE
28 Organization: _ Thomas&Hutton
29 Street address: 1020 Euclid Ave
30 Cjy,State,Zip: Charlotte,NC 28203
31 Phone number(s): [phone]
32 Email: [e-mail]
Certification Statement:
I certify,under penalty of law that this Supplement-EZ farm 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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DRAINAGE AREAS
1 Is this a hi.h density project? Yes
If so,number of drainage areas/SCMs _ 2
Does this project have low densi areas? No
4 If so,number of low densi drainage areas 0
Is all/part of this project subject to previous rule
5 versions? I No
FORMS LOADED
DRAINAGE AREA INFORMATION Entire Site 1 2
4 Type of SCM N/A Sand Filter Sand Filter
5 iTotal drainage area(sq ft) L 418,152 374,507 j 43,645 _
6 lOnsite drainage area(sq ft) _ 398,368 _ 354,738 43,630 __
7 Offsite drainage area(sq ft) _ 19,784 — 19,769 15
8 Total BUA in project(sq ft) 213431 sf 205736 sf 7695 sf
New BUA on subdivided lots(subject to
9 ipermittingEs}New BUA not on subdivided lots(subject to 126720 sf T 119040 sf _ 7680 sf —
10 ipermitting)(sf) 66949 sf 66949 sf _
11 1Offsite BUA(sq ft) 19762 sf T 19747 sf 15 sf _
12 Breakdown of new BUA not on subdivided lots: __ _ ___
-Parkin _(sq ft) _ 1290 sf 1290 sf N/A
-Sidewalk(sq ft) 14615 sf 14615 sf N/A __
_ -Roof(sq ft)_ - - — _ N/A -
-Roadway(sq ft_—_ 51044 sf _ 51044 sf — N/A ___
-Future(sq ft) N/A N/A _ N/A _
-Other,please specify in the comment box
ibelow( g ft) N/A N/A N/A
' New infiltrating permeable pavement on
13 subdivided lots(sq ft) N/A N/A _ N/A
New infiltrating permeable pavement not on
14 (subdivided lots(sq ft) N/A N/A _ N/A _
Existing BUA that will remain(not subject to
15 permittingj(sq ft) N/A N/A — N/A
16 Existing BUA that is already permitted(sq ft) _ N/A _ N/A N/A
17 Existing BUA that will be removed(sq ft) N/A N/A N/A
_ 18 Percent BUA 51% 55% _ 18% —
_ 19 Design storm(inches) 1.0 in 1.0 in 1.0 in _
20 Design volume of SCM(cu ft) 17751 cf 16992 cf __ 759 cf _
21 Calculation method for design volume ` Simple Simple Simple
ADDITIONAL INFORMATION
Please use this space to provide any additional information about the
22 drainage area(s):

SAND FILTER
1 Drainage area number 1 2
2 Minimum r uired treatment volume(cu ft 12744 sf 569 sf
3 Is the SCM sized to treat the SW from all surfaces at build-out? Yee Yes
4 Is the SCM located away from contaminated soils? Yes Yes
5 What are the side slopes of the SCM(H:V)? 3:1 3:1
6 Does the SCM have retaining walls,gabion walls or other No No
engineered side slopes?
7 Are the inlets,outlets,and receiving stream protected from erosion Yes Yes
(10-year storm)?
8 Is there an overflow or bypass for inflow volume in excess of the Yes Yes
design volume?
9 What is the method for dewatering the SCM for maintenance? Drawdown Orifice Drawdown Orifice
10 If applicable,will the SCM be cleaned out after construction? Yes Yes i11 Does the maintenance access comply with General MDC(8)? Yes Yes
12 Does the drainage easement comply with General MDC(9)? Yes Yes
If the SCM is on a single family lot,does(will?)the plat comply with
13 General MDC(10)? N/A NIA
14 Is there an O&M Agreement that complies with General MDC(11)? Yes Yes
15 Is there an O&M Plan that complies with General MD C(12)? Yes Yes
16,Does the SCM follow the device specific MDC? Yes Yes
17 Was the SCM designed by an NC licensed professional? Yes Yes
SAND FILTER MDC FROM 02H.1056
18 SHWT elevation(fmsi) u �Not Found _ Not Found
19 T pe of sand filterSopen or closed) Open Open
20 If closed,will the filter will be pre-cast or pour-in-place? N/A N/A
21 If closed,top of gyrate elevation(fmsl) N/A N/A
22 Is this sand filter designed to attenuate peak flows? Yes Yes
Sediment Chamber
231Volume that can be retained in the sediment chamber(cubic feet) 8008 cf 751 cf
24 Will there be a permanent pool in the sediment chamber? No _ No
25 Bottom of the sediment chamber(fmsl) 534.00 537.00
26 Area of the sediment chamber(square feet) 3274 sf 576 sf
27 Physical depth of the sediment chamber(inches) 24 in _ 12 in
28 Ponding depth in the sediment chamber,above any permanent 24 In 12 in
__ pool(inches)
29 Elevation of top of weir between chambers(fmsl) 536 538
Sand Chamber
30 Volume that can be retained in the sand chamber(cubic feet) 60231 cf 3550 cf
31 I Bottom of the sand chamber(fmsl) 531.50 534.50
32 Area of the sand chamber(square feet) 3976 sf 1787 sf
33 Physical depth of the sand chamber(inches) 54 in 48 in _
Ponding depth in the sand chamber,above the sand surface
34(inches) 24 in _ 18 in
35 Elevation of the bypass device(fins!) 536 538.5
36 Type of bypass device Weir Weir
37 Mechanism for distributing flow over the sand surface Natural Flow Natural Flow
38 Sand specification for sand chamber ASTM C33 or ASTM C33 or
equivalent _ equivalent _
39 Depth above underdrain pipe(inches) _ 18 in 18 in
40 Will the media be maintained to drain at least two inches per hour at Yes Yes
the sand surface?
41 Is at least one clean-out pipe provided at the low point of each Yes Yes
_ underdrain line'?
_ 42 Will clean-out pipes becapp d? Yes Yes
ADDITIONAL INFORMATION
43 Please use this space to provide any additional information about
the sand filter(s):
18)Geotech analysis did not find evidence of SHWT within the vicinity of
:the proposed SCMs.See report prepared by Southern Engineering.30)
Sand chamber volume includes storage above sediment chamber and
below the bypass device.