SW3220301_Plansheet - SCM Detail_20220420

Entire P
Adjacent pavement (if ,
applicable)
ariater of sand filter
The erirn to r oaf the d p and
P e �'` P
The inlet Swale
The embankment '
Forebay or pretreatment area
Filter bed and undardrain
collection system
Outlet device
Receiving crater
Trash/debris is present.
Sediment Is present on the
pavement surface.
Areas of bare soil andtor
erosive gullies have formed.
Vegetation is too short or too
long,
Areas of bare soil and/or
erosive gullies have formed.
Erosion is occurring in the
Swale, ,
Shrubs have started to grows on
the embankment,
Evidence of muskrat or beaver
activity is present.
A tree has started to grown on
the embankment.
An annual inspection her an
appropriate professional shows
that the embankment needs
repair'.
Sediment has accumulated to a
depth of greater than six
inches.
Erosion has occurred.
Weeds are present,
Water Is pending on the surface
for more than 24 hours after a
sto
Clogging has occurred,
The outlet device Is damaged
Erosion or other Signs of
damage have occurred at the
outlet.
Remove# +` i
as soon as possibW
Reg *,. soil If necessary to
remove- gully,, then
time and a one-time fertilizer
application.
Mai 6tain vegetation
appropriate -.
remove the gully, ,, then
lime r a one-time
application.
to smooth it over # provide
to avoid future problems
erosion.
Remove . -,
Mpt
consultand
professional
remove•'
to remove
Make all needed # .
Search for . of
sedimentsediment and remedy the
problem if possible. Remove
the rl StabiliZeor
it will not impacts•,
streams #
r the BMP.
Provide addi • i r
protection• d
to prevent erosion
problems.
• •If
•• r- -•
spraylng�
Check to see If the collector
cloggedsystem is and flush if
•
• r• 11111611 •
, _
water still ponds, then consult
expert,an
Clean out the outlet
Repairor replace the outlet
device.
Contact- NC Division ,
Water Resources,
FILTERSAND MAINTENANCE
hours1. During the first 3 months after construction inspections should be made after every storm event.
Thereafter, the sand filter should be inspected at least once a quarter (every 3 months) and within 24
-
Frequency2. The sand chamber should be raked periodically to remove surface sediment, trash, and delaris.
not
to
exceedone year.
3. First 2 or 3 inches of sand should be removed and replaced with new sand when water is ponding on the
surface for more
4. Clean out -•iment chamber whenever sedimentaccumulated to s. depth greater
Remove sediment and stablize. Remedy source of sediment If possible,
5. Heplace the sand filter media whenever It fails to function properly
6. All contaminated -.. • and sediment removed to be disposed of in accordance with local,,
federal regulations.
7. Maintain operation and maintenance records In a known set location. Operation and maintenance records
shall be made available upon
1 D FILTER t"iCIVI
NTS
20'x26'(52OsD SAND CHAMBER
TOP OF , M :#
TOP OF y r EL = 557.63
RIP
a P
BERM
SEPARATING
y it a y
1
i +
it lox,M
PVC
CLEANOUT
INVERT = 555.60
10'-6 PERF SCH-40 PVC
SLOPED @ 0.5%
PVC CLEANOUT
INVERT = 555.54
7'-6" SOLID SCH-40 PVC
SLOPED 0.5%
OUTLET STRUCTURE
INVERT = 555.5
SEE OUTLET STRUCTURE
J DETAIL THIS SHEET
f ,
%
; " 40 -15 P
p / LOPED @ 0.75%
WITH F S
i
ro
TOP OF DAM 10.0'
MINIMUM WIDTH
s -
FILTERL, SAND *.LAYOUT
0.17' (2"+/-) THICK LAYER
FILTER FABRIC � `� 3"-#57 WASHED STONE
(Bottom Layer) \_ SCARIFIED SUBGRADE
6" SCHEDULE 40 PERFORATED PVC (NOT COMPACTED)
3"-#57 WASHED STONE 4-HOLE, 3/6" PERFORATIONS, 6" ON CENTER
ALONG TOP & SIDES HOLE ROTATION AT SHOWN
1. ReferenceSKIMMER
BASINr. :,:SCIVI CONSTRUCTION
SEQUENCE (Sheet• x to ..
completed prior to underdrain and sand filter construction
2. Temporary silt fence to be installed around perimeter of proposed sand chamber.
3. Subgrade of sand filter to be scarified (not compacted).
4. Bottom of proposed filter to be lined with Mirafi 140n, or equal, filter fabric.
5. 6" Sch-40 perforated PVC pipes to be placed on top of filter fabric.
6. Perforations shall be 3/8" and spaced 6" on center along four longitudinal rows spaced 900 apart.
7. Perforated PVC pipe to be placed at a minimum slope of 0.5% and rotated such that holes are not placed on
bottom. Spacing of parallel PVC underdrain lines to not exceed 10'.
♦ r
chamber and sides and top of i
. #57 washed stone to be placed along bottom of
VC to a thickness of 3".
r: of • r washed stone.
. #57 stone to be covered with
10. An 18" thick layer of clean, washed, course masonry sand (ASTM C33 or =• particles less
average diameter is to be placed in the sand chamber.
11. Refer to note # 6 of SKIMMER BASIN CONVERSION & SCM CONSTRUCTION SEQUENCE (Sheet 4).
PUM
r : Y
1.'
# 7 WASHED STONE 6"
I
zNo MEMO -
• `' r ! . • r
rd
rj
. *
rz
.�* �, .: . *, a ,, r► _ -* .' i # � • -
•
♦
•
`� . a � � ',*♦ . . .. :.. • ..r :: I~ r i r `r r
4• � � `� • • ! , Ili # l i #, i- #' - � #
"
u5l5i 1116111IM1. ''.•. ,r
Ili IIIII``I`iIII�I ';9I �'"'"•
555
„ rir i .+ a - r ' -- o* a+, *r • r: r
NOTES:GENERAL
CONCRETEi BE USED THROUGHOUT.
2. PIPE ouTLEr STRUCTURETO BE STRUCK
INSIDEri r AND BRUSHED SMOOTH.
3. FORMS TO BE USED FOR CONSTRUCTION OF BOTTOM
CONCRETE4. COVER:
1. AREA UNDER EMBANKMENTx xr.:r GRUBBED, AND STRIPPED OF
ANY VEGETATION AND ROOT
MAT. THE
POOL
AREA
y SHALL BE
CLEARED.
2. SUBGRADE FOR DAM TO
BE PRO r _PRIOR
TO EARTH
r PLACEMENT.
ANY • PUMPING AREAS ARE BE UNDERCUT , r ,
w WITH
COMPACTED
" EARTH
CORE TRENCH TO BE
TED TO GOOD CLAY SOIL MATERIAL. TRENCH
EARTH +rCOMPACTED TO MINIMUM OF . OF r PROCTOR
MAXIMUM DRY
r
MATERIAL
. THE FILL r
i ROOTS OR
EMBANKMENT k
WOODYOTHER
VEGETATION AS AS OVERSIZED ORGANIC
OBJECTIONABLEMATERIAL OR OTHER MATERIAL.
EMBANKMENT
MAXIMUMBE COMPACTED BY TRAVERSING WITH EQUIPMENT WHILE BEING CONSTRUCTED.
15. COMPACTED EARTH FILL TO HAVE DRY UNIT WEIGHT OF AT LEAST 90 PCF.
ALL EARTH FILL TO BE COMPACTED TO MINIMUM OF 95% OF STD. PROCTOR
DRY DENSITY.
6. EXCAVATED SIDE SLOPES TO BE STABILIZED WITH SOD IN ACCORDANCE WITH
SPECIFICATIONS.
7. FINAL DAM INTERNAL EMBANKMENT SLOPES TO BE TRACKED AND STABILIZED
WITH SOD IN ACCORDANCE WITH SPECIFICATIONS,
1°
RIP RAP
SPILLWAY EL. 560.3
TOP OF DAM
EL. 561.5
CROSS SECTION
a• REM 4"CONCH EMERGENCY SPILLWAY N TS
COVER
ROVER 3 5$0.3 19"wx3-h
131W x 8°h " .. PENING (3 Sides)
ENING (3 $Idea)
n 13"
° 559.3 0" 559.30
;0
p
CH WIDTH
1 III II
(FOrErndad
DrBfn} ;> a& 3'Tbmaded Capped PVC TRENCH
v (PPE� 11- -F
WDTH
P.
�. T } �tr
55 8 a Sand =TTI GRADE11T-
r`
3c s°
_ Ii
v
1I-
I
�k
ti. • `k l
=
1
15"NQPE a � o- '
.�1- A I Ia I1(-
PIPE
555.5 60 16" PVC Underdratn a _ �
a II ITH
a'<
��.
SECTION X-XI- Ia I II
SECTION Y-Y - ., aan- II=i uu E a"
�1TI • I �� a (GAMECONCRETE OUTLET s
STRUCTUREI
IT= ..•a w� ITT =1 ` g r
- I :. , •: i:; "• :IT � p . --Ill-1 E
PLR M
ANTI-SEEPLL N T3
r
r ,
a
ii DDING
ar
PVC CLEANOUTen 3 Side561.5
T ENDS
_. Si __ _ _____
c�10 E1=560.45 _ _ _ _ _.Is
�
Q50 EI=560.3 _. --- - - - - .,_._ -. _ _ _ 1
Class T_______________________m 10 EI=560.05 - - - - __ __ _ _ _ �_.�___ 6prap L.iri r° spillway--'-
IP A -------------,.______- -i, Q2 EI=5 .76 -
1 1=559,5 _ -
SAND CHAMBER
QV=559,43 _
MIN. 520 SF SURFACE AREA 1 OV(Ad])=5,09
1 • ' TOP OF ASHD STONE - 557 i30 it
TOP OF SAND = 557.63 _
Storm = 26
..��
1) 4'x4' 0.5' Concrete1 4I Natural Ground layer of
Antiseep Collar
r-57±
ached stone. .
_ --------_---- -�
-�- tura o o a a o a o o a o o a a a a o -------
55. ottaIII I UUhtTKtNUM
Clean, washed, course masonry son IN -SITU SOIL of SandFilter DETAIL THIS (AST C or equal) with particles ,
less than m average diameter r
2 sry6" Sch-40 Perforated V 4 -1 "HDPE o-ub II al' c t -
-Holed /S Perforations, on center aints s II v t i ht seals
Hole Rotation at 4-6- .'clack n
�l
r
4' MIN
DEPTH
CORE TREINICH
DETAIL NTS
0