SW8030921_COMPLIANCE_20030924

STORMWATER DIVISION CODING SHEET
POST -CONSTRUCTION PERMITS
PERMIT NO.
SW SYD
DOC TYPE
El CURRENT PERMIT
❑ APPROVED PLANS
❑ HISTORICAL FILE
PCOMPLIANCE EVALUATION INSPECTION
DOC DATE
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YYYYMMDD

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BACKGROUND
FOOD LION LLC
Food Lion Store P749
Morehead City, Carteret County, NC
Stormwater Management
Sand Filter
Design Criteria
(revised 9-18-03)
The Food Lion Corporation desires to build a new Food Lion Store in the same location as an exsiting
Winn Dixie Store in the Parkway Shopping Center The footprint of the new store is somewhat narrower
but longer than the existing structure This causes expansion to the rear of the building and the need for
additional drive and loading space The existing asphalt drive will need to be expanded at the rear of the
building Currently all stormwtater runoff sheet flows along the access drive into a drainge that eventually
empties into Peltier Creek No stormwater structures currently exist behind the shopping center Total
runoff from the Food Lion impervious area will be approximately 15 acres Size and volume of the
forebay and sandfilter were sized based on criteria as set forth in the design guide Stormwater Best
Management Practices In order to contain the entire V of rainfall (within the first few hours of the storm)
the structure would have to be much larger
The site location, Food Lion design and limited space available were taken into consideration
Therefore, the Design Intent is as follows
Runoff from adjacent, unimproved areas, pervious and impervious will be allowed to
drain, untreated to the Creek by means of existing surface drainage channels as they've
always done
2 The area of new asphalt ,concrete and roof will be incorporated into the new stormwater
management system
3 Stormwater runoff from impervious surfaces will be collected in a drop inlet catch basins
and conveyed to a key manhole structure near the sand filter
4 The KEY manhole will be designed with an overflow pipe, set at a design height which
will allow runoff in excess of the first flush (I-inch)to bypass the stormwater filtration
system and discharge directly to the creek
The stormwater filter shall have (1) a sediment chamber, (2) CMU overflow weir and
(3) a surface sand filter with underdram discharge to the drainage The filter design shall
be in accordance with NCDENR's Stormwater Best Management Practices Manual, latest
edition
6 The Sand Filter System design criteria, attached hereto, identifies State minimum standards
and the actual design intent, which equals or exceeds State criteria
1 of 4

SAND FILTER DESIGN CRITERIA
A Forebay — Sediment Pool
1 Design Runoff Control Volume
2 Design Tributary Drainage Area
3 Design Rainfall Vol Per Event
4 Basin Volume 4*A*�
5 Side Water Depth
6 Wet Surface Area Allowance
7 Inlet Control
8 Outlet Control
B Sand Fitter Basin
1 Design Storm
2 Rainfall Intensity
3 Expected Runoff Flow Rate
Based on Q=CiA
C=0 90
I= 2 38 in /hr
A= 15 ac
4 Wet Storage Volume Allowance
5 Side Water Depth
6 Sand Filter Surface Area
7 Design Filtration Rate
8 Method of Discharge
9 Maximum Discharge Rate
10 Time to Drain
11 Maximum Water Level in Filter
12 Freeboard
13 Interbasm Weir Elevation
14 Key Manhole Control
Elevation (18" dia Pipe)
15 Key Manhole Rim Elevation
16 Discharge Inv Elevation
@ drainage ditch
Required Engineer's
Design Design
1-inch of Rainfall
15 acres
40,730 gallons
540 cf/ac
1,225 c f
( 810 cf)
Min 18-inches
18-inches
360 sf/ac
1,047 sf
(860 sf)
-
Overflow MH
Weir
Weir to Sand
Filter
10 yr, Tc 10 yr, 1 hour
2 38 -- inch/hr
3 21 cfs (max )
540 cf/ac
1,225 cf
(810 cf)
(9,153 gals )
18-in (Min)
18 inch
360sf
(540 s f)
596 s f
0 04 gpm/sf
0 04 gpm/sf
Underdrain piped to drainage ditch
-
24 gpm
-
6 hours
-
Elev 9 5 fl
-
1 0 ft
-
93ft
Elev 9 5 ft
Elev 12 5 ft
50ft
2 of 4

LOADING RATE CALCULATIONS FOR FILTRATION
OF UNTREATED STORMWATER
Food Lion
Morehead City, North Carolina
o Desian of Filter Flow -Through Capacity
The NCDENR Manual for Stormwater Best Management Practices (SwBMP), dated April 1999,
establishes the average recommended filtration rate at 0.04 gal.mm/sf with one (1) foot of
head on the sand surface A second requirement is that the first inch of rainfall runoff should
pass through the filter within a 24-hour period.
Sand from local sources within the Onslow County area are able to meet the following
specifications
f- Effective grain size
T Uniformity Co -Efficient
—� Dust Content
Permeability
10-20mm
< 3
< 10
6 — 20 in/hr rM Design = 4 0 in/hr
The Design Specification for sand filter media can be met by local sources of supply However, prior to
delivery, the sand shall be tested for compliance with the above standards
The following analysis has been prepared for this specific Stormwater Filter application
o Design Permeability of Filter Sand 4 0 m/hr
o Sand Type Local Supply
o Calculations
P = 4 0 in/hr , = 4 x 144 = 576 in3/sf/hr
576 x 004329 = 2 5 gph/sf
-- 60 = 0.041 GPM/S.F.
o Filter Operation
** Filter Area
** Filtration Rate
** Liquid Vol @ Max
S WD (2 0')
** Min. Drain Time
** Max Drain Time
596 s f
596 x 041 = 24 gpm
1225 c f /9,160 gals
(9160 — 24) = 380 min = 6 3 hrs.
24 hours
3 of 4

Misc. Calculations
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STAGE vs VOLUME
POND AREA_(Forebay and Sandfilter each side)
ELEV � AREA (sf},"IncFnc VQL(c , ' Total VOL(cf} ;, �k� _ —WDIF In EI
112 area
8
596
91 0
0
(o 5
1
9
887
7415
7415
Onp
101T
05
95
1047
4835
1225
05
10
1207
5635
17885
1
11
1555
1381
31695

A B
C D E
F G
H I J
K I L
l
Ef"71
01190®R,111'iDATE
8 "HE-;0ylll-
08/��103
DESIGN PHASE
2
PRELIM ! X 1
CONSTR ! 1
REVISION ! !
RECORD 1 !
OTHER ! 1
(SPECIFY)
3
PROJECT NAME
FOOD LION
PROJECT NO
20034032
4
5
LOCATION
MOREHEAD
BY
TW
6
7
CHECKED BY
T1N
8
9
n= 0 014
�= 195
h= 22
STORM DRAINAGE SCHEDULE CONTINUE
site with building
10
11
12
13
AREAS
(INLETS)
INLET
AREA
(AC)
INLET
Cc
RUNOFF
COEFF
INLET
DISCHARGE
(CFS)
TOTAL
AREAS
(AC)
INLET
TIME
(MIN}
PIPE
TIME
(MIN)
Tc
TIME
OF CONC
(MIN)
I
INTENSITY
(IN/HR)
Cc
RUNOFF
COEFF
FROM TO
N14
15
i6
17
18
'
19
ScenanoI
20
CB1
KEYMH
Al
150
090
321
150
500
000
6000
238
090
21
KEYMH
FES1-PND
A2
001
090
002
151
Soo
006
6000
238
090
22
23
24
Scenano 2
25
CB1
KEYMH
Al
1150
0 90
321
150
5 00
000
5 00
722
090
25
KEYMH
FES2-CRK
A2
001
090
002
151
500
006
500
722
0 90
27
28
29
30
NOTE SCENARIO ONE ASSUMES THAT THE STORM IS THE 1 r 1hr
31
32
NOTE SCENARIO TM ASSUMES THAT THE STORM IS THE 1 r 5MIN Tc
33
uyfguNfkyfmyhl[mhy Date 8/13103 Time 4 08 PM Pere I of 12

A B
M N O P O R
S T U
V I W
1
.,,� `s s� r�F,S�� � � �ary�24+o ay �y
ff t' •�'v�$
DATE
08/13/03
DESIGN PHASE
2
PRELIM 1 X 1
CONSTR 1 1
REVISION I 1
RECORD / /
OTHER I I
(SPECIFY)
3
4
PROJECT NAIVE
FOOD LION
PROJECT NO
20034032
5
LOCATION
MOREHEAD
BY
JTW
6
7
CHECKED BY
TW
8
9
10
11
12
13
n= 0 014
g= 195
h= 22
STORM DRAINAGE SCHEDULE - rQNTINUE©
Ei
DISC #ARUE
q
SIDE-
STREAM
(CFS)
SLOPE
DIA
pN)
CAPAI(TY
{F# MI
V FULL
(FPS)
LENGTH
(FT)
SEGMENT
TIME
(MIN)
UPPER
INV
(FT)
LOUVER
INV
(FT)
UPSTREAM
TOP
ELEV
(FT)
14
15
FROM TO
16
17
18
19
ScenanoI
20
C131
KEYMH
3 21
0 0100
18
98
55
20
006
860 i
840
1100
21
KEYMH
FES1-PND
323
00400
18
195
110
10
002
8 40
800
1250
22
23
24
Scenano 2
25
CB1
KEYMH
975
00100
18
98
55
20
006
860
840
1100
26
KEYMH
FES2-CRK
982
0 1167
18
33 3
18 8
30
003
950
6001
1250
27
28
29
30
31
32
33
uyfgufyfkyfmyhfFmhy Date 8113/03 Time 4 08 PM Page 2 of 12

A A
B
X
Y Z AA
AB AC
AD
AE
AF
AG
All
1
sAN'�
�.x.l�o
rya 2Y" 4 SfWN
Qar
DATE
08/13/03
DESIGN PHASE
2
PRELIM
CONSTR
REVISION
RECORD
OTHER
(SPECIFY)
1 X I
1 1
(_ /
I 1
3
PROJECT NAME
FOOD LION
PROJECT NO
20034032
4
5
LOCATION
MOREHEAD
BY
TW
6
7
8
CHECKED BY
Tw
9
n=
9=
h=
0014
195
22
WoflAULJC GRADE LINE
PIPE HYDRAULIC SIDESTREAM
AREA RADIUS SUMMATION Hf
(FT) (FT) (CFS)
90 DEG=O 7
60 DEG=O 55
HEAD LOSS
He He
BEND LOSS
Hb
K'S
30 DEG 28
15 DEG=010
HI
BEND
LOSS
K
CONTINUED
FRICTION
SLOPE
(FTIFT)
— N
FRICTION
VELOCITY
(FPS)
11
d10
12
13
14
FROM TO
15
16
17
18
19
Scenano 1
20
CBI
KEYMH
17671
03750
000
002
001
000
000
003
000
00011
181
21
KEYMH
FES1-PND
17671
03750
000
001
001
002
000
004
000
00011
182
22
23
24
Scenano 2
25
CBS
KEYMH
17671
03750
000
020
012
0 00
000
032
000
1 00099
549
26
KEYMH
FES2-CRK
17671
03750
000
030
012
016
000
058
0 00
00101
553
27
28
29
30
31
32
33
uyfgufyfkyfmyhffmhy Date 8113A3 Time 4 08 PM Page 3 of 12

A B
AI AJ AK AL AM AN AO
AP AQ AR
AS
5
PROJECT NAME
FOOD LION
DATE
01/00/00
DESIGN PHA
PRELIM
CONSTR
REVISION
RECORD
OTHER
(SPECIFY)
3
PROJECT NO
20034032
4
5
LOCATION
MIOREHEAD
BY
TW
6
7
CHECKED BY
TVV
8
9
n= 0014
9= 195
h= 22
HYDRAIUMG
D
NE- fONIINUED
DESIGN CRITERIA
1 10 YR STORM 1 hr
DESIGN CRITERIA
1 10 YR STORM 5 mmTc
10
11
12
13
OUTLET
W S ELEV
(FT)
INLET
W S ELEV
FLOW
CONDITION
CONTROL
1
COMMENTS
14
FROM TO
OUTLET
CONTOL
(FT)
INLET
CONTROL
(FT)
USE
(FT)
15
16
17
18
19
Scenano 1
20
CBI
KEYMH
960
963
949
963
OUTLET
137
OK
21
KEYMH
FES1-PND
920
924
929
929
INLET
321
OK
22
23
24
Scenano 2
25
C131
KEYMH
1158
1190
1066
1190
OUTLET
0 90
OVERFLOW
26
KEYMH
FES2-CRK
720
778
1158
1158
INLET
092
OK
27
28
29
30
31
32
33
uyfgul wrnyhlfmhy pate sn W3 Time 4 08 PM Page 4 of 12

®
o'x;'"''� jDATEDESIGN
j�(
1kMimlk'i
08/13/03
PHASE
PRELIM
1 X 1
PROJECT NAME
PROJECT NO
CONSTR
1 I
FOOD LION
2003403
REVISION
1 I
LOCATION
BY
RECORD
1 1
MOREHEAD
TW
OTHER
1 1
CHECKED BY
(SPECIFY)
TW
Storm Outlet Structure
FES No =
' ' FES 1
Pipe Dia=
18
in
Q10 =
3 23
cfs
Qfull =
19 51
cfs
VfUll =
1102
fps
From Fig
8 06 b 1
From Fig
8 06 b 2
Storm Outlet Structure
FES No =
I FES2
Pipe Dia=
18
in
Q 10 =
9 82
cfs
Qfull =
33 32
cfs
Vfull =
18 83
fps
From Fig
8 06 b 1
From Fig
8 06 b 2
Q10/Qfull = 017
V1Vfu 1I = 072
V = 7 9 fps
Zone -- 1
D5o
- 4 in
DMAx
= 6 in
Riprap Class
= A
Apron Thickness
= 9 in
Apron Length
= 60 ft
Apron Width = 3xDia
= 45 ft
Q101Qfull = 029
VNfull = 085
V = 16 1 fps
Zone = ,1
D50 = 4 in
DMAx = 6 in
Riprap Class = A
Apron Thickness - 9 in
Apron Length = 6 ft
Apron Width = 3xDia - 45 ft
Is 10304100131ADMINIfoodhonstorml0 As LATEST REVISION 8113103 4 19 PM PAGE 1 OF 2