SW3191202_3 - Northgate Supplemental Form_1/2/2020

SUPPLEMENT-EZ COVER PAGE
FORMS LOADED
:OJECT INFORMATI N
1 Project Name
2 Project Area ac
3 Coastal Wetland Area
The Residence at No
7.53
4 1 Surface Water Area ac 0
5 Is this project High or Low Density? High
6 Does this project use an off -site SCM? No
COMPL E WITH 02H .1003(4)
7
Width of vegetated setbacks provided (feet)
25' front and rear setbacks; 5' side setback
8
Will the vegetated setback remain vegetated?
Yes
9
Is BUA other that as listed in .1003 4 c-d out of the setback?
Yes
10
Is streambank stabilization proposed on this project?
No
BER AND TYPE
11
Infiltration System
0
12
Bioretention Cell
0
13
Wet Pond
0
14
Stormwater Wetland
0
15
Permeable Pavement
0
16
Sand Filter
1
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
1 Dry Pond
0
23
StormFilter
0
24
Silva Cell
0
25
Ba filter
0
26
Filterra
0
FORMS LOADED
SIGNER CERTIFICATION
27
Name and Title:
Brian Smith, PE
28
Or anization:
Urban Design Partners
29
Street address:
1318-e6 Central Avenue
30
City, State, Zip:
Charlotte, NC 28205
31
Phone numbers :
704-334-3303
32
1 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.
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12.13.2019
Date

DRAINAGE AREAS
1
Is this a high density project?
Yes
2
If so, number of drainage areas/SCMs
1
3
Is all/part of this project subject to previous rule
versions?
No
FORMS LOADED
A INFORMATION
Entire Site
1
M
N/A
Sand Filter
in ro ect s ft
103966 sf
92114 sf
on subdivided lots (subject to permitting)
7permitting)
N/A
N/A
outside of subdivided lots (subject to
s
103966 sf
92114 sf
8
Offsite -total area (sq ft
12931 sf
12931 sf
9
Offsite BU(sq ft
1790 sf
1790 sf
10
Breakdown of new BUA outside subdivided lots:
Parkin (sq ft
48669 sf
48669 sf
Sidewalk (sq ft
23024 sf
9381 sf
Roof (sq ft
32274 sf
32274 sf
Roadway s ft
N/A
N/A
Future (sq ft
N/A
N/A
Other, please specify in the comment box
below (sq ft
N/A
N/A
11
New infiltrating permeable pavement on
subdivided lots (sq ft
N/A
N/A
12
New infiltrating permeable pavement outside of
Isubdivided lots (sq ft
N/A
N/A
13permitting)
Exisitng BUA that will remain (not subject to
s ft
N/A
N/A
14
Existing BUA that is already permitted (sq ft
N/A
N/A
15
Existing BUA that will be removed (sq ft
8706 sf
8706 sf
16
Percent BUA
32%
43%
17
Design storm inches
1 in
1 in
18
Design volume of SCM cu ft
5852 cf
5852 cf
19
1 Calculation method for design volume
TSS
TSS
ADDITIONAL INFORMATION
20
Please use this space to provide any additional information about the
drainage area(s):
N/A
DRAINAGE AREA INFORMATION
Entire Site
1
4
Type of SCM
N/A
Sand Filter
5
Total BUA from project (sq ft)
6
1995 rules
SL 2006-246
2008 rules
2017 rules
103966 sf
92114 sf
7
New BUA on subdivided lots (subject to
permitting) (sq ft)
1995 rules
SL 2006-246
2008 rules
2017 rules
N/A
N/A
8
New BUA outside of subdivided lots (subject to
permitting) (sf)
1995 rules
SL 2006-246
2008 rules
2017 rules
103966 sf
92114 sf
9
Offsite - total area (sq ft)
1995 rules
SL 2006-246
2008 rules
2017 rules
12931 sf
12931 sf
10
JOffsite BUA (sq ft)
1995 rules
SL 2006-246

2008 rules
2017 rules
1790 sf
1790 sf
11
Design storm (inches)
1995 rules
SL 2006-246
2008 rules
2017 rules
1 in
1 in
12
Breakdown of new BUA:
Parking (sq ft
48669 sf
48669 sf
Sidewalk (sq ft)
23024 sf
9381 sf
Roof (sq ft
32274 sf
32274 sf
Roadway (sq ft)
N/A
N/A
Future (sq ft
N/A
N/A
Other, please specify in the comment box
below (sq ft
N/A
N/A
13
New infiltrating permeable pavement on
Isubdivided lots (sq ft
N/A
N/A
14
New infiltrating permeable pavement outside of
subdivided lots (sq ft
N/A
N/A
15
Exisitng BUA that will remain (not subject to
permitting) (sq ft)
N/A
N/A
16
Existing BUA that is already permitted (sq ft
N/A
N/A
17
Existing BUA that will be removed (sq ft
8706 sf
8706 sf
18
Percent BUA
32%
43%
19
Design volume of SCM (cu ft)
5852 cf
5852 cf
20
Calculation method for design volume
TSS
TSS
ADDITIONAL INFORMATION
21
Please use this space to provide any additional
information about the drainage area(s):
N/A

SAND FILTER
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)?
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 (10-
Iyear storm)?
Yes
8
Is there an overflow or bypass for inflow volume in excess of the design
volume?
Yes
9
What is the method for dewatering the SCM for maintenance?
Drawdown Orifice
10
If applicable, will the SCM be cleaned out after construction?
Yes
11
Does the maintenance access comply with General MDC (8)?
Yes
12
1 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)?
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 SCM designed by an NC licensed professional?
Yes
ISAND FILTER MDC FROM 02H .1056
18
SHWT elevation (fmsl)
19
Type of sand filter (open or closed)
Open
20
If closed, will the filter will be pre -cast or pour -in -place?
21
If closed, top of grate elevation (fmsl)
22
Is this sand filter designed to attenuate peak flows?
Yes
I Sediment Chamber
23
Volume that can be retained in the sediment chamber (cubic feet)
9225 cf
No
24
Will there be a permanent pool in the sediment chamber?
25
Bottom of the sediment chamber (fmsl)
906.00
26
Area of the sediment chamber (square feet)
4040 sf
27
Physical depth of the sediment chamber (inches)
48 in
28
Ponding depth in the sediment chamber, above any permanent pool
(inches)
24 in
29
Elevation of top of weir between chambers (fmsl)
908
Sand Chamber
30
Volume that can be retained in the sand chamber (cubic feet)
9210 cf
31
Bottom of the sand chamber (fmsl)
905.00
32
Area of the sand chamber (square feet)
3585 sf
33
Physical depth of the sand chamber (inches)
48 in
34
Ponding depth in the sand chamber, above any permanent pool
(inches)
24 in
35
Elevation of the bypass device (fmsl)
36
Type of bypass device
37
Mechanism for distributing flow over the sand surface
38
Sand specification for sand chamber
cleaned washed
"concrete" sand
bed
39
Depth above underdrain pipe (inches)
Will the media be maintained to drain at least two inches per hour at the
sand surface?
18 in
40
Yes
41
Is at least one clean -out pipe provided at the low point of each
underdrain line?
Yes
42
Will clean -out pipes be capped?
Yes
INFORMATION
Please use this space to provide any additional information about the
43 Sand Filter(s):
N/A
Sand Filter 4 11:56 AM 11/26/2019