HomeMy WebLinkAboutSW5230802_Supplement-EZ Form_20240612 SUPPLEMENT-EZ COVER PAGE
FORMS LOADED
PROJECT INFORMATION
1 Project Name Chatham Habitat for Humanity Townhouses
2 Project Area(ac) 3.12
3 Coastal Wetland Area(ac) 0
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)? 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: Robert W.Brantly,P.E.-Consulting Engineer
28 Organization: Engineering&Environmental Science Co.
29 Street address: 3008 Anderson Dr.Ste.102
30 City,State,Zip:131 Phone number(s):
Raleigh,NC 27609
919-781-7798
32 Email: e2s@bellsouth.net
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 \\ 11111/1
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1984 ' -- Signature of Designer
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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 N/A N/A
5 Total drainage area(sq ft) 135907 135907
6 Onsite drainage area(sq ft) 135907 135907
7 Offsite drainage area(sq ft) 0 0
8 Total BUA in project(sq ft) 28583 sf 28583 sf
New BUA on subdivided lots(subject to permitting)
9 (sq ft) 19200 sf 19200 sf
New BUA not on subdivided lots(subject to
10 permitting)(sf) 9383 sf 9383 sf
11 Offsite BUA(sq ft) sf sf
12 Breakdown of new BUA not on subdivided lots:
-Parking(sq ft) 6918 sf 6918 sf
-Sidewalk(sq ft) 2465 sf 2465 sf
-Roof(sq ft) sf sf
-Roadway(sq ft) sf sf
-Future(sq ft) sf sf
-Other,please specify in the comment box
below(sq ft) sf sf
New infiltrating permeable pavement on
13 subdivided 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) sf sf
16 Existing BUA that is already permitted(sq ft) sf sf
17 Existing BUA that will be removed(sq ft) 3280 sf 3280 sf
18 Percent BUA 19% 19%
19 Design storm(inches) N/A N/A
20 Design volume of SCM(cu ft) N/A N/A
21 Calculation method for design volume N/A N/A
ADDITIONAL INFORMATION
Please use this space to provide any additional information about the
22 drainage area(s):
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) 3:1 min.
5 Maximum velocity in the vegetated conveyances during the 10-year storm? 2.15
6 Are curb outlet swales proposed? No
7 Maximum longitudinal slope of curb outlet swale(s)(%)
8 Bottom width of curb outlet swale(s)(feet)
9 Maximum side slope of curb outlet swale(s)(H:V)
10 Minimum length of curb outlet swale(s)(feet)
11 Are treatment swales used instead of curb outlet swales?
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
I14 Are variations to rule.1003 proposed? Yes
I ADDITIONAL INFORMATION
15 I Please use this space to provide any additional information about this low density project:
The proposed Impervious/RUA et the sits will be less than 24%.Runoff will generally be conveyed by vegetated swales end sheet flow over vegetated areas,These design requirements
for Low Density permitting per 15A NCAC 02H.1003(2)are met for this project.
To comply with stormwater ordinances reviewed and enforced by the local jurisdiction(Town of Slier City),a runoff detention erea with sufficient storage to meet these local requirements
is provided on-silo.Please note that Ihis Is not a stets required SCM,and Is only being Installed to meal local jurisdiction requirements.
Discharge from the detention area will be to a wide vegetated area,which will allow all runoff from the site to be conveyed off-site vie dispersed flow over vegetated areas.A minimum 30•
vegetated area will be provided between the detention area discharge and the properly line.
Drainage Pervious
Swale BUA Q Slope Vagew Va„„A Flow depth
N Area area C
(ac) (cfs) (%) (fps) (fps) (ft)
(ac) (ac)
1 1 0.03 0.01 0.02 0.59 0.13 12.50 3.50 1.15 0.18
'A 2 0.11 0.03 0.08 0.51 0.41 7.70 3.50 1.14 0.30
a 3 2.66 0.35 2.31 0.43 8.66 5.00 3.50 2.15 0.35
3 4 2.94 0.43 2.52 0.44 9.82 5.00 3.50 1.53 0.38
5 0.22 0.12 0.10 0.67 1.11 2.50 3.50 0.47 0.50
A 6 0.24 0.12 0.13 0.64 1.17 5.00 3.50 0.78 0.56
r 7 0.16 0.11 0.05 0.77 0.94 5.00 3.50 0.62 0.39
.CA 8 0.18 0.11 0.07 0.72 1.00 5.00 3.50 0.83 0.46
6 9 0.17 0.14 0.04 0.83 1.08 5.00 3.50 0.74 0.39
d A 10 0.22 0.14 0.08 0.72 1.19 3.30 3.50 0.68 0.47
j g I 11 0.54 0.16 0.39 0.53 2.19 1.00 3.50 0.93 0.89
yjj� 12 0.01 0.00 0.01 0.35 0.04 2.00 3.50 0.25 0.24
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