SW5221001_Supplement-EZ Form_20240402

SUPPLEMENT-EZ COVER PAGE
FORMS LOADED
PROJECT INFORMATION
1 Project Name Umstead State Park Campground Improvements
2 Project Area(ac) 150.4
3 Coastal Wetland Area(ac) 0
4 Surface Water Area(ac) 1.8
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) 50
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 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 CERTIFICATION
27 Name and Title: John F.Watson
28 Organization: Finch and Associates
29 Street address: 309 N.Boylan Ave
30 City,State,Zip: Raleigh,NC 27603
31 Phone number(s): 919-833-1212
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.
Designer
``��I11111111/�/''
•- O-* E S S p `•?/y',
•
SEAL • — Signature of Designer
= 039760 =•
'•FHGINEE�•'
///JohnlF.IW ao-•„•` 4/2/2024
Seal Date

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 1
Is all/part of this project subject to previous rule
5 versions? No
FORMS LOADED
DRAINAGE AREA INFORMATION Entire Site LD 1
4 Type of SCM none none
5 Total drainage area (sq ft) 6,549,600 6,549,600
6 Onsite drainage area (sq ft) 6,549,600 6,549,600
7 Offsite drainage area (sq ft) J 0 0
8 Total BUA in project (sq ft) 188599 sf 188599 sf
New BUA on subdivided lots (subject to permitting)
9 (sq ft) sf sf
New BUA not on subdivided lots (subject to
10 permitting) (sf) 71700 sf 71700 sf
11 Offsite BUA (sq ft) sf sf
12 Breakdown of new BUA not on subdivided lots: 0 0
- Parking (sq ft) 37400 sf 37400 sf
- Sidewalk (sq ft) 4300 sf 4300 sf
- Roof(sq ft) 3000 sf 3000 sf
- Roadway (sq ft) 8600 sf 8600 sf
- Future (sq ft) sf sf
- Other, please specify in the comment box
below (sq ft) 18400 sf 18400 sf
,
New infiltrating permeable pavement on subdivided
13 lots (sq ft) sf sf
New infiltrating permeable pavement not on
14 subdivided lots (sq ft) sf sf
Existing BUA that will remain (not subject to
15 permitting) (sq ft) 116899 sf 116899 sf
16 Existing BUA that is already permitted (sq ft) sf sf
17 Existing BUA that will be removed (sq ft) 63600 sf 63600 sf
18 Percent BUA 3% 3%
19 Design storm (inches) NA NA
20 Design volume of SCM (cu ft) NA NA
21 Calculation method for design volume NA NA
ADDITIONAL INFORMATION
Please use this space to provide any additional information about the
22 drainage area(s):
BUA not categorized under item #12 above consists of surface components
for septic system and hardscape campsite areas for picnic tables and tent
setup.

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) I 3 sf
5 Maximum velocity in the vegetated conveyances during the 10-year storm? 2.5
6 Are curb outlet swales proposed? No
7 Maximum longitudinal slope of curb outlet swale(s)(%) NA
8 Bottom width of curb outlet swale(s)(feet) NA
9 Maximum side slope of curb outlet swale(s)(H:V) NA
10 Minimum length of curb outlet swale(s)(feet) NA
11 Are treatment swales used instead of curb outlet swales? No
12 Is stormwater released at the edge of the setback as dispersed flow? Yes
13 Have stormwater outlets been designed to prevent downslope erosion? Yes
14 Are variations to rule.1003 proposed? No
ADDITIONAL INFORMATION
15 Please use this space to provide any additional information about this low density project:
4.Side slope of Vegetated conveyances:3:1
13.Flow velocities in vegetated conveyances are not sufficient to require rip-ra d ators.
Drainage Pervious
Swale BUA Q Slope V,now V,au,i Flow depth
Area area
(ac) (cfs) (%) (fps) (fps) (ft)
(ac) (ac)
1 0.74 0.27 0.47 0.40 2.10 0.70 4.00 1.40 0.73
2 0.94 0.32 0.62 0.40 2.70 3.00 4.00 2.50 0.75
3
4
5
s_
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30