SW4220601_Supplement-EZ Form_20221221

SUPPLEMENT-EZ COVER PAGE
FORMS LOADED
PROJECT INFORMATION
1
Project Name
Havenbrooke SubdMsion
2
Project Area ac
74A9
3
Coastal Wetland Area (ac)
0
4
Surface Water Area (ac)
0.78
5
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?
Yes
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
Sioretention Cell
13
Wet Pond
14
Stormwater Wetland
15
Permeable Pavement
16
i8and Filter
17
Rainwater Harvesting RWH
18
Green Roof
19
Level Spreader -Filter Strip LS-FS)
20
Disconnected Impervious Surface (DI5
21
Treatment Swale
22
23
Q Pond
StormFilter
24
Silva Cell
25
Bayfilter
2$
Filterra
FORMS LOADED
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 knowiedge 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.
¢ttttsrtet#,
4•; �,rESS/O �y
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SEAL
• 18584
Date

DRAINAGE AREAS
1
Is this a high density project?
No
2
If so, number of drainage areaslSCMs
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
DRAINAGE AREA INFORMATION
Entire Site I.D 1
4
'Type of SCM
NIA NIA
5
Total drainage area (sq ft)
3,276,616 3,276,616
6
Onsite drainage area sq ft
3,231,716 3,231,716
7
Offske drainage area ft
44,900 44,900
8
Total BUA in Nject sq ft
358388 sf 358388 sf
9
New BUA on subdivided lots (subject to permitting)
s ft)
213000 sf 213000 sf
10
New BUA not on subdivided lots (subject to
permittin sn
127983 sf 127983 sf
11
lOffsite BUA (sq ft
17405 sf 17405 sf
12
Breakdown of new BUA not on subdivided lots:
- Parkina (so ftl
sf sf
Sidewalk �sq ft)
18438 sf 18438 sf
Roof (sq ft
sf sf
Roadway s ft)
- Future (sq ft
109545 sf 109545 sf
sf sf
[-
Other, please specify in the comment box
below(so ft
Sf sf
13subdivided
New infiltrating permeable pavement on
lots (sq ft)
sf sf
14
New infiltrating permeable pavement not on
subdivided lots (sq ft)
sf sf
15permitting)
Existing BUA that will remain (not subject to
s ft
sf sf
16
ExistingBUA that is already permitted (sq ft
sf sf
17
"sting BUA that will be removed (sq ft
sf sf
18
Percent BUA
11% 11%
19
20
21 [Calculation
AAi11T1A\I
Desi n storm inches
Design volume of SCM cu ft)
method for design volume
AI Ia,�we�a• a �,w..
NIA NIA
NIA NIA
N/A
Irlq l Ivlr
Please use this space to provide any additional information about the
- drainaae arealsl
single family

LOW DENSITY
D IGN
RE UIREMENTS FOR LOW DENSITY PROJECTS FROM 02H .1003
Is project below density thresholds set forth in the applicable slormwater rule?
Yes
1
2
Does project maximize dispersed flow and minimize chennelization of flow?
Yes
3
Has the use of piping been minimized per. 1003(2)(.)?
No
4
Side slopes of the vegetated conveyances (H:V)
3 sf
5
6
Maximum velocity, in the vegetated conveyances during the 10-year storm?
Are curb outlet swales proposed?
4.53
No
7
Maximum longitudinal slope of curb outlet swale(s) (%)
No
8
Bottom width of curb outlet swale(s) (feet)
No
9
Maximum aide slope of curb outlet swale(s) (H:V)
No
10
Minimum length of curb outlet swale(s) (feet)
No
Are treatment swaies used instead of curb outlet swales?
No
r14
Is stormwater released at the edge of the setback as dispersed flov. ?
Yes
Have stormwater outlets been designed 10 prevent downslope erosion?
Yes
Are variations to rule .1003 proposed?
No
ADDITIONAL INFORMATION
15 iPlease
use this space to provide any additional information about this low density project:
Line 4 is nut formatted properly. The side sle es are 3:1
Swale
#
Drainage
Area
ae
BUA
(aaJ
Pervious
area
(at),(cfs)
C
Q
Stop.
{y,)
V,i -
(fps)
V,�,
(fps)
Flow depth
{ft)
1
0.35
0.16
0.19
0.50
1.2D
3.00
5.00
1.41
0.30
2
0.19
0.05
0.14
0.50
0.$5
2.76
5.00
1.05
0.23
3
5.02
0.85
4.17
0.50
13.73
4.26
5.00
2.88
0.97
4
0.61
0.10
0.51
0.50
2.09
4.27
5.00
1 A4
0.44
5
0.37
0.11
0.26
0.50
1.27
4.64
5.00
1.24
0.34
8
T
8
1.42
5.84
2.70
0.07
0.00
1.12
1.35
5.84
1.58
0.50
0.50
0.50
4.86
15.97
7.38
4.60
4.18
4.21
5.00
5.00
5.00
2.06
4,53
3.42
0.61
0.80
0.58
9
3.57
0.07
3.50
0.50
8.15
5.00
5.00
3.90
0.56
10
7.84
1.46
6.38
0.45
18.73
5.00
S.pO
3.60
1.06
11
0.93
0.24
0.69
0.50
3.18
2.20
5.00
1.73
0.52
12
3.41
0.19
3.22
0.50
8.85
3.80
5.00
3.46
0.65
13
0.36
0.06
0.30
0.50
1.23
1.77
5.00
1.07
0.37
14
1.56
0.00
1.58
0.50
4.05
4.19
5.00
2.72
0.45
15
2.82
1.04
1.78
0.60
7.32
4.76
5.00
3.66
0.55
16
1.68
0.65
1.03
0.50
5.79
2.34
5.00
2.24
0.06
17
4.36
0.39
3.97
0.45
13.42
5.00
5.00
3.13
0.91
1s
19
20
21
22
23
24
25
28
27
28
29
30