SW6241002_Supplement-EZ Form_20241118

SUPPLEMENT-EZ COVER PAGE
FORMS LOADED
(PROJECT INFORMATION
1 Project Name Powder Horn Subdivision
2 Project Area (ac) 18.6
3 Coastal Wetland Area (ac) 0
4 Surface Water Area (ac) 0
5 Is this project High or Low Density? Low
6 Does this project use an off-site SCM? No
COMPLIANCE WITH 02H .1003(4) I
7 Width of vegetated setbacks provided (feet) 0
8 Will the vegetated setback remain vegetated? No
9 If BUA is proposed in the setback, does it meet NCAC 02H.1003(4)(c-d)? N/A
10 Is streambank stabilization proposed on this project? No
NUMBER AND TYPE OF SCMs:
11 Infiltration System
12 Bioretention Cell
13 Wet Pond
14 Stormwater Wetland
15 Permeable Pavement
16 Sand Filter
17 Rainwater Harvesting (RWH)
18 Green Roof
19 Level Spreader-Filter Strip (LS-FS)
20 Disconnected Impervious Surface (DIS)
21 Treatment Swale
22 Dry Pond
23 StormFilter
24 Silva Cell
25 Bayfilter
26 Filterra
FORMS LOADED
DESIGNER CERTIFICATION
27 Name and Title: William K. Marsh, PE
28 Organization: Marsh Engineering Services
29 Street address: 5624 Toby Place Road
30 City, State, Zip: Stedman, NC 28391
31 Phone number(s): 910-229-5814
32 Email: [e-mail]
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
Signature of Designer
Seal Date

DRAINAGE AREAS
1 'Is this a high density project? No
2 If so, number of drainage areas/SCMs 0
3 Does this project have low density areas? Yes
4 If so, number of low density drainage areas 1
Is all/part of this project subject to previous rule
5 versions? No
FORMS LOADED
DRAINAGE AREA INFORMATION Entire Site LD 1
4 Type of SCM Low Density _ Low Density
5 Total drainage area (sq ft) 810,108 810,108
6 Onsite drainage area (sq ft) 810,108 _ 810,108
7 Offsite drainage area (sq ft) 0 0
8 Total BUA in project (sq ft) 194425 sf 194425 sf
New BUA on subdivided lots (subject to
9 permitting) (sq ft) 144249 sf 144249 sf
New BUA not on subdivided lots (subject to
10 permitting) (sf) 50176 sf 50176 sf
11 Offsite BUA (sq ft)
12 Breakdown of new BUA not on subdivided lots:
- Parking (sq ft)
- Sidewalk (sq ft) _
- Roof(sq ft)
- Roadway (sq ft) 50176 sf 50176 sf
- Future (sq ft)
- Other, please specify in the comment box
below (sq ft)
New infiltrating permeable pavement on
13 subdivided lots (sq ft)
New infiltrating permeable pavement not on
14 subdivided lots (sq ft)
Existing BUA that will remain (not subject to
15 permitting) (sq ft)
16 Existing BUA that is already permitted (sq ft)
17 Existing BUA that will be removed (sq ft)
18 Percent BUA 24% 24%
19 Design storm (inches)
20 Design volume of SCM (cu ft)
21 Calculation method for design volume
ADDITIONAL INFORMATION
Please use this space to provide any additional information about the
22 drainage area(s):

LOW DENSITY
DESIGN REQUIREMENTS FOR LOW DENSITY PROJECTS FROM 02H .1003
1 Is project below density thresholds set forth in the applicable stormwater rule? Yes
2 Does project maximize dispersed flow and minimize channelization of flow? Yes
3 Has the use of piping been minimized per.1003(2)(c)? Yes
4 Side slopes of the vegetated conveyances (H:V) 3
5 Maximum velocity in the vegetated conveyances during the 10-year storm? 5
6 Are curb outlet swales proposed? No
7 Maximum longitudinal slope of curb outlet swale(s)(%) N/A
8 Bottom width of curb outlet swale(s) (feet) N/A
9 Maximum side slope of curb outlet swale(s) (H:V) N/A
10 Minimum length of curb outlet swale(s) (feet) N/A
11 Are treatment swales used instead of curb outlet swales?
12 Is stormwater released at the edge of the setback as dispersed flow? N/A
13 Have stormwater outlets been designed to prevent downslope erosion? Yes
14 Are variations to rule .1003 proposed? No
ADDITIONAL INFORMATION T
15 Please use this space to provide any additional information about this low density project:
Drainage Pervious
Swale BUA Q Slope Vallow Vactual Flow depth
Area area C
# (ac) (cfs) (%) (fps) (fps) (ft)
(ac) (ac) _
1 1.22 0.19 1.03 0.40 3.88 1.00 5.00 7 1.59 0.82
2 0.44 0.07 0.37 0.40 1.40 1.00 5.00 1.11 0.57
3 0.72 0.11 0.61 0.40 2.29 1.66 5.00 1.78 0.58
4 0.16 0.06 0.10 0.55 0.70 1.66 5.00 1.17 I 0.37
5 1.68 0.39 1.29 0.45 4.81 1.00 5.00 1.71 0.89
6 2.28 0.70 1.58 0.50 6.11 0.75 5.00 1.57 1.06
7 2.47 0.76 1.71 0.50 6.62 2.00 5.00 2.88 0.80
8 3.77 1.45 2.32 0.55 11.11 0.50 5.00 1.53 1.48
9 1.24 0.48 0.76 0.55 3.66 2.00 5.00 2.34 0.64
10 0.95 0.37 0.58 0.55 3.32 0.75 5.00 1.27 0.85
11 0.36 0.14 0.22 0.55 1.58 1.00 5.00 1.16 0.59
12 5.47 0.84 4.63 0.40 13.92 0.50 5.00 1.65 1.36
13 0.28 0.11 0.17 0.55 1.23 1.00 5.00 1.06 0.54
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15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30

Low Density (continued)
Drainage I Pervious
Swale# Area BUA area C Q Slope Vallow Vactual
(ac) (ac) (ac) (cfs) (%) (fps) (fps)
31
32
33
34
35
36
37
38
39
40

Flow
depth (ft)
1