SW6231102_Supplement-EZ Form_20231102

SUPPLEMENT-EZ COVER PAGE
FORMS LOADED
PROJECT INFORMATION
1 Project Name Buffalo Creek Subdivision
2 Project Area(ac) 52.2
3 Coastal Wetland Area(ac)
4 Surface Water Area(ac) 0
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)? Yes
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 Bayfilter 0
26 Filterra 0
FORMS LOADED
DESIGNER CERTIFF CATION
27 Name and Title: Jarrod E.Hilliard, PE
28 Organization: Hilliard Engineering,PLLC.
29 Street address: P.O.Box 249
30 City,State,Zip: Sanford,NC 27331
31 Phone number(s): [phone]
32 Email: jhilliardOhilliardengineerinmcom
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.
Designer
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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 3
Is all/part of this project subject to previous rule
5 versions? No
FORMS LOADED
DRAINAGE AREA INFORMATION Entire Site LD 1 LD 2 LD 3
4 Type of SCM
5 Total drainage area(sq ft) 2273025 788436 165528 69696
6 Onsite drainage area(sq ft) 2273025 788436 165528 69696
7 Offsite drainage area(sq ft)
8 Total BUA in project(sq ft) 323151 sf 248895 sf 52254 sf 22002 sf
New BUA on subdivided lots(subject to permitting)
9 (sq ft) 164500 sf 52500 sf 35000 sf 7000 sf
New BUA not on subdivided lots(subject to
10 permitting)(sf) 158651 sf 196395 sf 17254 sf 15002 sf
11 Offsite BUA(sq ft)
12 Breakdown of new BUA not on subdivided lots:
-Parking(sq ft)
-Sidewalk(sq ft) 22177 sf 17076 sf 3548 sf 1553 sf
-Roof(sq ft)
-Roadway(sq ft) 136474 sf 105084 sf 21835 sf 9555 sf
-Future(sq ft)
-Other,please specify in the comment box
below(sq ft)
New infiltrating permeable pavement on
13 subdivided lots(sq ft)
New infiltrating permeable pavement not on
14 subdivided lots(sq ft)
Existing BUA that will remain(not subject to
15 permitting)(sq ft)
16 Existing BUA that is already permitted(sq ft)
17 Existing BUA that will be removed(sq ft)
18 Percent BUA 14% 32%. 32% 32%
19 Design storm(inches)
20 Design volume of SCM(cu ft)
21 Calculation method for design volume
ADDITIONAL INFORMATION
Please use this space to provide any additional information about the
22 drainage area(s):
Percent BUA is based on total project area.

LOW DENSITY
DESIGN REQUIREMENTS FOR LOW DENSITY PROJECTS FROM 02H.1003
1 Is project below density thresholds set forth in the applicable stormwater rule? Yes
2 Does project maximize dispersed flow and minimize channelization of flow? Yes
3 Has the use of piping been minimized per.1003(2)(c)? Yes
4 Side slopes of the vegetated conveyances(H:V) 3 sf
5 Maximum velocity in the vegetated conveyances during the 10-year storm? 3.04
6 Are curb outlet swales proposed? Yes
7 Maximum longitudinal slope of curb outlet swale(s)(%) 7%
8 Bottom width of curb outlet swale(s)(feet) 3 ft
9 Maximum side slope of curb outlet swale(s)(H:V) 3:1
10 Minimum length of curb outlet swale(s)(feet) 100 ft
11 Are treatment swales used instead of curb outlet swales? No
12 Is stormwater released at the edge of the setback as dispersed flow? No
13 Have stormwater outlets been designed to prevent downslope erosion? Yes
14_Are variations to rule.1003 proposed? No
F----
DITIONAL INFORMATION
5 i Please use this space to provide any additional information about this low density project:
*BUA&Pervious areas are for the swale drainage areas only
Swale Drainage BUA Pervious Q Slope V,ib„, V,n,,,, Flow depth
Area area C
# (ac) (cfs) (%) (fps) (fps) (ft)
(ac) (ac)
1 18.10 5.7* 12.4* 0.35 57.32 1.00 6.00 3.04 1.80
2 3.80 1.19* 2.26* 0.35 11.24 0.50 5.00 1.53 1.03
3 1.80 0.50* 1.30* 0.35 4.89 1.80 5.00 3.18 0.35
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