SW1220701_Supplement-EZ Form_20230329

SUPPLEMENT-EZ COVER PAGE
FORMS LOADED
PROJECT INFORMATION
1
Project Name
All About Plumbing Building Addition
2
Project Area (ac)
3.15
3
Coastal Wetland Area (ac)
_
0
0
4
Surface Water Area (ac)
5
1 Is this project High or Low Density?
Low
6
Does this project use an off -site SCM?
No
COMPLIANCE
WITH 02H .1003(4) -
7
Width of vegetated setbacks provided (feet)
30
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 0
12
Bioretention Cell
0
13
Wet Pond
0
14
Stormwater Wetland
0
15
Permeable Pavement
0
16
Sand Filter
0
17
Rainwater Harvesting (RWH)
0
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
0
23
StormFilter
0
24
Silva Cell
0
25
Ba filter
0
26
1 Filterra
0
FORMS LOADED
DESIGNER CERTIFICATION
27 Name and Title: J. David McCutchen, P.E.
28
Organization:
McCutchen Engineering Associates, PC
29
Street address:
898 West Saint John Street
30
City, State, Zip:
Spartanburg, SC 29301
31
Phone number(s):
864-582-0585
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.
\\O\\\pP� FES......
2Q SEAL r i
025335
r
%INE�P:
41CCV��:?��
Seal
4 5;, T10"s M, 1/6 d§r
of
dZ�Ixr
5
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
5
Is all/part of this project subject to previous rule
versions?
No
FORMS LOADED
jDRAINAGE AREA INFORMATION
4 Type of SCM
Entire Site
LD 1�
-
5
Total drainage area (sq ft
137,214
6
Onsite drainage area sq ft)
137,214
7
Offsite drainage area (sq ft
0
8
Total BUA in project (sq ft)
57935 sf
9
New BUA on subdivided lots (subject to permitting)
(sq ft
N/A
10permitting)
New BUA not on subdivided lots (subject to
s
14376 sf
11
Offsite BUA (sq ft
N/A
12
Breakdown of new BUA not on subdivided lots:
Parking (sq ft
7841 sf
Sidewalk (sq ft
N/A
Roof (sq ft
6535 sf
Roadway (sq ft)
N/A
Future (sq ft
N/A
- Other, please specify in the comment box
below (sq ft
N/A
13
New infiltrating permeable pavement on
subdivided lots (sq ft
N/A
14
New infiltrating permeable pavement not on
subdivided lots (sq ft
N/A
15permitting)
Existing BUA that will remain (not subject to
sq ft
43560 sf
16
Existing BUA that is already permitted (sq ft
sf i
17
Existing BUA that will be removed (sq ft
N/A
18
Percent BUA
15%
19
Design storm inches
7.1 in
20
Design volume of SCM (cu ft)
f
21
Calculation method for design volume
ADDITIONAL INFORMATION
22
Please use this space to provide any additional information about the
drainage area(s):

LOW DENSITY
DESIGN
REQUIREMENTS FOR LOW DENSITY PROJECTS FROM 02H .1003
Is project below density thresholds set forth in the applicable stormwater rule?
Does project maximize dispersed flow and minimize channelizatlon of flow?
Has the use of piping been minimized per. 1 003(2)(c)?
Side slopes of the vegetated conveyances (H:V)
Yes
Yes
Yes
3 sf
1
2
3
4
5
Maximum velocity in the vegetated conveyances during the 10-year storm?
2.97
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?
No
12
Is stormwater released at the edge of the setback as dispersed flow?
Yes
13
Have stormwater outlets been designed to prevent downslope erosion?
Yes
14 I Are variations to rule .1003 proposed?
ADDITIONAL INFORMATION
15 1 Please use this space to provide any additional information about this low density project:
J No
Vegetated grass swales were designed using mannin s equation. See drainage swale calculations in Appendix
D of the SWPPP.
Swale
#
Drainage
Area
BUA
(ac)
Pervious
aarea
c
Q
(cfs)
Slope
N
V,11,w
(fps)
V,«,,A
(fps)
Flow depth
(ft)
1
0.82
0.57
0.25
0.77
4.50
5.00
4.00
2.97
0.45
2
0.27
0.15
0.12
0.68
1.30
2.00
4.00
1.38
0.32
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30