20181245 Ver 2_SuppEZ 8_17_20_20200817

SUPPLEMENT-EZ COVER PAGE
FORIVIS LOADED
Pl7OJ]ECT INFORMATION
Project.Name Ferguson Street Development
2 Project Area ac 22.31 Acres
3 Coastal Wetland Area ac _ 0 --
4 Surface Water Area ac 3133
5 is this ra ect High or Low Densi 7 High
6 floes this project use an off-site SCM? No
COMPLIANCE WI:6jjWA2 i.[4
7 1 Width of etated setbacks provided feet N/A
8 lWiil the v etated setback remainvegetated? NIA
9 Ilf BUA is prop2sed in the setback,does it meet NCAC 02H_10 4)Jc-d? N/A
10 1 Is strreambank stabilization proposed on this project? No
NUMBER AND TYPE OF S.CMs:
11 linfiftration System
12 Biaretention Cell 1
13 Wet Pond
t4 Stomtwater Wetland
15 Permeable Pavement
16 Sand Filter
17 Rainwater Harvesting RWH
18 Green Roof
19 Level Spreader-Filter Stn LS-FS
20 Disconnected Impervious Surface DIS
21 Treatment Swale
22 Dry Pond
23 StormFilter
24 Silva Cell --
25 Ba Iter
26 Flterra
FQRMSLOADED
DESIGNER CERTIFICATION
27 Name and Title WiNiam A.Stillwell,Pro ect E lneer
28 D anization: Sttlh%*Jl Engineer€.Inc.
28 Street address: 42 Marsh Lily brine
30 City.State Zip- Zukun,NC 28779
31 Phone numbe s: 828.586,6066
32 Email: w.stilts+e€[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.
t7esr4ner
lirk CA
n
'zp E551p
= Q SEAL Signature of Designer
026084
70
t111W0 Date
Sea

DRAINAGE AREAS
!, Is this a high densitproject? v. . _ Yes..
2 if so number of drains a areas/SCMs 2 _
3 Does this project have low densy areas? No _
4 If so,number of low clensy drainage areas 0
Is alllpart of this project subject to previous rule
5 versions? No
FARMS LOAI)E❑
DRAINAGE AREA INFORMATION Entire Site 1 2
4 1 TvDe of SC None Bioretention Cell
5 Total drainage areas ft 124582 sf 22216 sf 102366 sf
fi lOnsite drainage area ft 103238 sf 22216 sf 81022 sf
7 Offsite drainage area(sq 41 sf s€ sf
8 Totai BUA in ro ct(sq ft sf sf sf
New BUA on subdivided lots(subject to permitting)
g ft sf sf sf
New BUA not on subdivided lots[subject to
10 ermittin� s sf sf sf
11 Offsite BUA ftl sf sf sf
12 Breakdown of new BUA not on subdivided lots:
7-Parkin (sqM
-Sidewalk q ft
-Root WE ft
-Road wa s It
-Futures ft
Other,please specify in the comment box
below ft
New infiltrating permeable pavement on
13 subdivided lots ft sf sf sf
New infiltrating permeable pavement not on
14 subdivided lots ft sf sf sf
Existing BUA that will remain{not subject to
15permitting) s ft sf sf sf
16 Fxistinq BUA that is already rrnitted s fl sf sf sf
17 Existing BUA that will be removed(sq ft 21344 sf sf 21344 sf
18 Percent BUA 22% 71%
18 Des n storm inches 1.0 in 1.0 in 1-0 in
20 Desi n volume of 5CM cu tt of Of 6743 cf
21 lGaiculation method for design volume Simple Method
ADDITIONAL INFORMATION.
Please use this space to provide any additional information about the
22 drains a area s]:
Drainage area has been split into two proposed parcels,one for a commercial
facility and one for a residential development.The residential development
parcel has been designed for low density_

BIORETENTION CELL
1 I Drainage area.number _ 2
2 !Minimum required treatment volume cu ft) ! 6683 cf
ENERALMM FROM 02H.1050 _
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 1 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-year 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? Pump(preferred)
10 If applicable,will the SCM be cleaned out after construction? Yes
11 Does the maintenance access comply with General MDC(8)? Yes
12 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)? NIA
14 is there an O&M Agreement that complies with General MDC(11)? No
15 is there an O&M Plan that complies with General MDC(12)? Yes
1e Does the SCM follow the device specific MDC? Yes
t7 Was the SCM designed by an NC licensed professional? Yes
BIORETENTION CELL.MDC FROM 02H.1052
18 SHWT elevation(fmsl] - ,W Unknown
19 1 Bottom of the bioretention cell(fmst) 2W.00
20 Ponding depth of the design storm(inches) 12 in
21 Surface area of the bioretention cell(square feet) LL 7459 sf
22 Desi n volume of SCM cu fl ee83 cf
23 is the bioretention cell used for peak attenuation? Yes
24 Depth of peak attenuation over planting surface(in) 24 in
25 Height of peak attenuation outlet above the planting surface(in) 18 in
26 Infiltration rate of the in situ soil(inch/hour) 2 inlhr
27 Diameter of the underdrain pipes(if applicable) 8 in
28 Does the design include Internal Water Storage(IWS)? Yes
29 if so,elevation of the top of the IWS(frnsl) 2143,5
30 Elevation of the planting surface(fmsl) 2145
31 What type of vegetation will be planted? (grass,trees/shrubs,
other)? Grass
32 Media depth(inches) 30 in
33 J.Percentege of medium to coarse washed sand by volume 75%
34 Percentage of fines(silt and day)by volume 8%
35 Percentage of organic matter by volume 5%
3e Type of organic material Pine Bark Fines
37 Phosphorus Index(P-Index)of media(unitless) 49 MAX
38 Will compaction be avoided during construction? Yes
39 Will cell be maintained to a one inchlhour standard? Yes
40 Depth of mulch,if applicable(inches) NIA
41 Type of mulch,if applicable NIA
42 r How many dean out pipes are being installed? 2
43 Type of pretreatment that will be used: FOREBAY
ADDITIONAL INFORMATION
44 jPeease use this space to provide any additional information about the
bioretention cell(s):
A drainage maintenanance and access easement has been tentatively
established but not yet recorded until review of stormwater plan is completed
-An operation and maintenance manual has been established but not yet
retarded until review of the plan is completed.SHWT is in excess of 2'below
proposed cell media,which is being placed entirely in a frll area
Bioretention 1 3.28 PM 8/14/2020