SW3220302_Supplement-EZ Form_20220613

SUPPLEMENT-EZ COVER PAGE
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PROJECT INFORMATION
1 Project Name
Denver Defense
2 Project Area (ac)
4.494
3 Coastal Wetland Area (ac)
N/A
4 Surface Water Area (ac)
N/A
5 Is this project High or Low Density?
High
6 Does this project use an off -site SCM?
No
NUMBER AND TYPE OF SCMs:
11 Infiltration System
12 Bioretention Cell
13 Wet Pond..
14 Stormwater Wetland
15 Permeable Pavement
16 Sand Filter .... .... .... .... .... .... .... .... .... .... ..1
17 Rainwater Harvesting TM)
18 Green Roof
19 Level Spreader -Filter Strip
20 Disconnected Impervious Surface (DIS)
21 Treatment Swale
22 Dry Pond ..
23 Storm Filter
24 Silva CelL........
25 Bayfilter
26 �Filterra
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DESIGNER CERTIFICATION
27
Name and Title:
Jay Henson, Principal
28
Organization:
HensonFoley
29
Street address:
121 Gilead Rd.
30
City, State, Zip:
Huntersvill, NC, 28078
31
1 Phone number(s):
704„-875-1615
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.
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Sign ture of besigner
6/9/2022
Date

DRAINAGE AREAS
.............................................................................................................................................................................................................................................................................
1
Is this a high density project?
Yes
2
lisp, 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
Is all/part of this project subject to previous rule
5
versions?
No
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DRAINAGE AREA INFORMATION
Entire Site
1
4
Type of SCM
N/A
sand filter
5
Total drainage area kq ft
195759
119449
6
Onsite drainage area (sq ft
195759
117333
7
Offsite drainage area s ft
0
2116
8
.........................................g..........................(sq......).........................................................................................................................................................................................................................
Total BUA in project (sq ft)
121358 sf
72929 sf
New BUA on subdivided lots (subject to
9
permitting) (sq ft)
N/A
N/A..
New BUA not on subdivided lots (subject to
10
ermittin sf
87385 sf
53641 sf
11
Offsite BUA s ft
N/A
2116 sf
12
Breakdown of new BUA not on subdivided lots:
Parking„ (sq ft)
51222 sf
40041 sf
- Sidewalk (sq ft)
1600 sf
1600 sf
Roof (sq ft)
17203 sf„
12000„sf
Roadway (sq ft)
Future„(sq ft)
17360 sf„
Other, please specify in the comment box
below (sq ft
New infiltrating permeable pavement on
13
subdivided lots (sq ft)
N/A
N/A
New infiltrating permeable pavement not on
14
subdivided lots (sq ft
N/A
N/A
Existing BUA that will remain (not subject to
15
permitting) (sq ft)
33973 sf
17172 sf
16
Existing BUA that is already permitted„ (sq ft)
17
Existing BUA that will be removed (sq ft)
16572 sf„
2900 sf
18
Percent BUA
49%
61 %
19
Design storm (inches)
1.0 in
1.0 in
20
Design volume of SCM (cu ft)
n/a
4611 cf
21
Calculation method for design volume
n/a
Simple RV method
ADDITIONAL INFORMATION
�Please use this space to provide any additional information about the
22
drainage a rea(s)
With
site conditions it was found impossible to get all new BUA to BMP. As
a comprimise, some existing BUA would be taken to bmp
and that the final
BUA
number to BMP was greater than proposed BUA.

SAND FILTER
III 1 Drainage area number
1
.............................................................
Yes
No
Yes
.............................................................
Yes
.............................................................
Drawdown Orifice
.............................................................
Yes
18
SHWT elevation (fmsl)
831.5
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
Sediment Chamber
23
Volume that can be retained in the sediment chamber (cubic feet)
2305 cf
24
Will there be a permanent pool in the sediment chamber?
No
25
Bottom of the sediment chamber (fmsl)
842.00
26
Area of the sediment chamber (square feet)
500 sf
27
Physical depth of the sediment chamber (inches)
18 in
28
Ponding depth in the sediment chamber, above any permanent
18 in
pool (inches)
29
Elevation of top of weir between chambers (fmsl)
843.5
Sand Chamber
30
Volume that can be retained in the sand chamber (cubic feet)
2305 cf
31
Bottom of the sand chamber (fmsl)
841.50
32
Area of the sand chamber (square feet)
525 sf
33
Physical depth of the sand chamber (inches)
24 in
34
Ponding depth in the sand chamber, above the sand surface
24 in
(inches)
35
Elevation of the bypass device (fmsl)
843:5
36
Type of bypass device
6" ORIFICE
37
Mechanism for distributing flow over the sand surface
RIP -RAP BERM
38
Sand specification for sand chamber
ASTM C33
39
Depth above underdrain pipe (inches)
18 in
40
Will the media be maintained to drain at least two inches per hour at
Yes
the sand surface?
41
Is at least one clean -out pipe provided at the low point of each
Yes
underdrain line?
42
Will clean -out oioes be capped?
Yes
Please use this space to provide any
43 the sand filter(s):
Sand Filter 1 4:03 PM 6/9/2022