SW6210302_Supplement-EZ Form_20210602

SUPPLEMENT-EZ COVER PAGE
L E011 MS LOADE D
-PROJECT
INFORMATION
Project Name Utility Improvements to Serve Maxwell Ridge
Project Area (ac) 14.229
Coastal Wetland Area (ac) -
Surface Water Area (ac) 0.008
1
2
3
4
5
Is this pro*ect High or Low Density?
High
6 j
Does this project use an off -site SCM?
No
COMPLIANCE WITH 02H.1003(4)_____
7
Wid.th of vegetated setbacks provided (feet)
30
8
Will the vegetated setback remain vegetated?
Yes
9
If BLIA is proposed in the setback, does it meet NCAC 02H.1003(4)(c-d)?
No
10
Is streambank stabilization proposed on this project?
No
NUMBER AND TYPE OF SCMs:
11
Infiltration System
Bioretention Cell
I
0
12
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
0
25
Bayfilt r
26
Filterra
0
I FORMS LOADED
DESIGNER CERTIFICATION
27 JNameandTitle:
28 lOrganization:
29 Istreetaddress:
30 ICity,State.ZiD
31 1 Phone number(s)
32 lEmail:
Matt Lowder, PE
4004 Barrett Drive, Suite 101
Raleiqh. NC 27609
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.
24434
I fill;
/-R /"-� L�'/
SigAture jA Designer
Date
be I I /V

DRAINAGE AREAS
I
ITS this �'�high density project?
Yes
2
If so, number of drainage areas/SCMs
1
3
Does this project have low density areas?
No
4
If so, number of low density drainage areas
0
5
Is all/part of this project subject to previous rule
versions?
No
I FORMS LOADED
;DRAINAGE AREA INFORMATION
Entire Site
i
4
Type of SCM
-
Infiltration Basin
5
Total drainage area (sq ft)
392290 sf
392290sf
6
Onsite drainage area (sq ft)
392290 sf
392290sf
7
Offsite drainage area (sq ft)
8
Total BUA in project (sq ft)
96311 sf
96311 sf
9
New BUA on subdivided lots (subject to permitting)
(sq ft)
10
New BUA not on subdivided lots (subject to
permitting) (sf)
11
Offsite BUA (sq ft)
12
Breakdown of new BUA not on subdivided lots:
—Parking (sq ft)
Sidewalk (sq ft)
3805 sf
3805 sf
Roof (sq ft)
64000sf
64000 sf
Roadway (sq ft)
Future (sq ft)
28506sf
28506sf
Other, please specify in the comment box
below (sq ft)
—
13
New infiltrating permeable pavement on
subdivided lots (sq ft)
14
New infiltrating permeable pavement not on
subdivided lots (sq ft)
15
Existing BUA that will remain (not subject to
permitting) (sq ft)
16
Existing BUA that is already permitted (sq 4)
17
Existing BUA that will be removed (sq ft)
18
Percent BUA
16%
26%
19
Design torm (inches)
1.0 in
20
Design volume of SCM (cu ft)
8858 ef
21
Calculation method for design volume
Simple Method
ADDITIONAL
INFORMATION
22 -1Please
use this space to provide a�—y —additional information about the
drainage area(s):

INFILTRATION SYSTEM
1 JDrainage area number I
2 1 Minimum reauired treatment volume (cu ft) 8868 cf
3
Is the SCM sized to treat the SW from all surfaces at build -out?
Yes
4
Is the SCM located away from contaminated soils?
Yes
5
What are the side slopes of the SCM (H:V or enter "Vertical" for
trenches)?
3:1
6
Does the SCM have retaining walls, gabion walls or other engineered
side slopes?
No
—
7
Are the inlets, outlets, and receiving stream protected from erosion
(1 0-year ston-n)?
Yes
—
8
Is there an overflow or bypass for inflow volume in excess of the
desiqn volume?
Yes
9
What is the method for dewatering the SCM for maintenance?
Pump (preferred)
10
If aeplicable, will the SCM be cleaned out after construction?
Yes
11
Does the maintenance access comply with General MDC (8�?
Yes
12
Does the drainage easement comply with General MDC (9)?
Yes
13
If the SCM is on a single family lot, does (will?) the plat comply with
General MDC (10)?
N/A
14
Is there an O&M Agreement that complies with General MDC (11)?
Yes
15
Is there an O&M Plan that complies with General MDC (12)?
Yes
16
Does the SCM follow the device specific MDC?
Yes
17
Was the SCIM desiqned bv an NC licensed professional?
Yes
18 Proposed slope of the subgrade surface(%)
19 Are te races or baffles provided? No
20 IType of pretreatment: I Forebay
Snits Data
21
Was the soil investigated in the footprint and at the elevation of the
infiltration system?
Yes
22
SHWT elevation (fmsl)
344.00
23
Depth to SHWT per soils report (in)
84.00
24
Ground elevation at boring in soils report (fmsl)
351.00
25
Is a detailed hydrogeologic study attached if the separation is
between 1 and 2 feet?
Yes
26
Soil infiltration rate (in/hr)
6.00
r27�Factor
7
of safety (FS) (2 is recommended)�
—2-00---1
IFlavatinn-z
29
Bottom elevation (fmsI)
347 ft
30
Storage elevation (fmsl)
349. fl.
31
Bypass elevation (fmsl)
351.8 ft
For Basins On!y
32 Bottom surface area (ft) 4720 ft
33 Storage elevation surface area (ft2 7885. ft
Fnr Trt-nchps Oniv
34
Length (ft)
35
Width
36
Perforated pipe diameter, if applicable (inches)
37
Number of laterals
38
Total length of perforated pjpinq
39
tone type, if applicable
40
Stone orosity (%)
41
Is stone free of fines?
42
Is the stone wrapped in geotextile fabric?
43
Has at least one inspection pDrt been provided?
1 44 IDesign volume of SCM (cuft) 8858 ef
1 45 1 Time to draw down (hours) 8 hrs
46 Please use this space to provide any additional information about the
� infiltration system(s):
Infiltration 1 10:13 AM 6/1/2021