SW6130203_Plansheet - SCM Detail_20240423

3.16 ACRES
Table 2:Sample Operation and Maintenance Provisions for Infiltration Basins CAR
ZONING: RA-20 R ;'37" W
�— .•FE•..D.••••�
SCM element: Potential problem: How to remediate the problem: 5 6 \\�0•��� s'i'�ned
The entire SCM Trash/debris is present. Remove the trash/debris. USE: VACANT J r $d E.
by JafrS,d E.
The grass filter strip or ' \ 'I SF,�HIIIIdrd,h,
other pretreatment area Areas of bare soil and/or erosive gullies Regrade the soil if necessary to H I I.7 I ar -
remove the gully,then plant ground Date: -'
cover and water until established.
0 23\
�i "I'
Provide lime and a one-time fertilizer `.•:�1 N ;
application (5`04'00'
Sediment has accumulated to a depth — ��,,, E[
greater than six inches. Search for the source of the sediment
and remedy the problem if possible. Sample Operation and Maintenance Provisions for Infiltration Basins I ip
Remove the sediment and dispose of 'O en Q)
Important maintenance procedures: �r
it in a location where it will not cause 1.The drainage area will be carefully managed to reduce the sediment load to / co \ M
impacts to streams or the SCM. S� co
the infiltration basin. �� � �
The flow diversion
2. No portion of the infiltration basin will be fertilized after the initial fertilization l � Q)structure(if applicable) The structure is clogged. Unclog the conveyance and dispose N N �
of any sediment off-site.
that is required to establish the vegetation. Lime may be allowed if vegetation SCM DRAINAGE AREA:
co6)
\
is planted on the surface of the infiltration system and a soil test shows that it is needed. � 374,616 SF � UIZ
The structure is damaged. Make any necessary repairs or replace ' co3.The vegetation in and around the basin will be maintained at a height of four to six inches.
if damage is too much for repair. 8.60 AC L
The basin More than four inches of — _ \ BASIN BOTTOM: 'DESIGN VOLUME':25,444 CIF d' Q)
After the infiltration basin is established, it will be inspected once a quarter and �26— _ — � N tr) Q.� �
sediment has accumulated. Search for the source of the sediment �� 420.00' (FROM OUTLET ELEVATION \ U M Q M
within 24 hours after every storm event greater than 1.0 inches(or 1.5 inches 7 and remedy the problem if possible. if in a Coastal County). Records of operation and maintenance will be kept in a 422.00 TO O L N
Remove the sediment and dispose known set location and will be available upon request. \ � N `�
of it in a location where it will not cause Inspection activities shall be performed as follows.Any problems that are found BOTTOM O F BASIN s Lo Q) CL
impacts to streams or the SCM. / \ — ELEVATION 420.00) oo� Ilk / o `�
shall be repaired immediately. / 'L
Erosion of the basin surface �
has occurred or riprap is displaced. Provide additional erosion protection _ MIN.SURFACE AREA FOR'DESIGN VOLUME': �'( �`). / Q) Z Q)
such as reinforced turf matting or riprap � SA=FSx[(DVx12)/(KxT)]
if needed to prevent future erosion problems. SA=2X[(25,444x12)/(0.9102)] /
Water is standing more than / S MIN.SURFACE AREA REQUIRED:9,320 SF U
three days after a storm event. Replace the top few inches of soil to see � SURFACE AREA PROVIDED: 11,373 SF Q� •V
if this corrects the standing water problem. L J
f not,consult and approve repair.
professional STO R M WATE R for a more extensive re air. � L
DRAINAGE N � -�
The embankment Shrubs or trees are growing on Cal •.....
STORM WATER MANAGEMENT NOTES: � E SEMENT
the embankment. Remove trees and shrubs immediately.
1. THE DEVELOPER OR HIS AGENT SHALL CONTACTTHE DESIGN ENGINEER WHEN THE BEST r .Z1 M
An annual inspection by an MANAGEMENT PRACTICES ARE CONSTRUCTED AND ABOUT TO BECOME OPERATIONAL SO THAT A �1 ,
appropriate professional shows FINAL INSPECTION CAN BE PERFORMED TO DETERMINE COMPLIANCE WITH THE APPROVED PLAN. •y'� �10
that the embankment needs repair. Make needed repairs immediately. 2. ANNUAL MAINTENANCE INSPECTION AND REPORT REQUIRED. THE OWNER OF A PERMITTED Dc TOP OF BANK I Q.)
STRUCTURAL STORM WATER BMP SHALL ANNUALLY SUBMIT MAINTENANCE AND INSPECTION 422
423.55' M 1 The outlet device Clogging has occurred. Clean out the outlet device and dispose REPORT FOR EACH BMP TO THE STORM WATER ADMINISTRATOR. ANNUAL INSPECTIONS SHALL BEGIN �I
of sediment off-site. WITHIN ONE YEAR OF THE RECORDATION OF ANY DEED(S)SHOWING STORM WATER BMPS. — \
3. UPON COMPLETION OF THE PROJECT,THE ENGINEER OF RECORD SHALL CERTIFY THAT THE i \
The outlet device is damaged. Repair or replace the outlet device. COMPLETED PROJECT IS IN ACCORDANCE WITH THE APPROVED STORM WATER MANAGEMENT PLANS \ '
AND DESIGNS. �
4. A FINAL INSPECTION OF THE SITE AND STORM WATER BMP SHALL BE SCHEDULED WITH AND
COMPLETED BY THE PROJECT ENGINEER. �Z
5. NCDEQ AND THEIR ASSIGNS HAVE RIGHT TO ACCESS THE STORM WATER CONTROLS FOR INSPECTIONS / k CHI NCE K
OR MAINTENANCE AS NECESSARY.
6. THE PROPERTY OWNER IS RESPONSIBLE FOR MAINTAINING THE STORM WATER CONTROLS 18' WIDE EMERGENCY /
ACCORDING TO THE APPROVED MAINTENANCE PLAN AND DIRECTION OF NCDEQ. \ EX UMP OVERFLOW WEIR:
�� a T11r�ON 423.25' WITH SODDING
8 .y�,
d, RIP RAP OUTLET�APRON
A 174.7598' — 4�s.>o X 2' WIDE AT OUTLET
�?1089.5581'� 3
� LQ
D9'1124 12' LONGf
" � � 4�002•
_ 13' WlbE AT TERMINUS
1 >8 RcfsgBo[9 _ SE 18" THICK CLASS B RIP RAP
O MIRIFI FILTER FABRIC %-4
NOTE: GRADE GRADE APRON TO 421.75 FROM \
PIPE OUTLET TO THE CENTER J
ROAD STORMWATER BASIN MAY BE CONSTRUCTED FOR USE d \
AS A TEMPORARY SEDIMENT BASIN DURING CONSTRUCTION. / OF TH E APRON
1115 ONCE CONSTRUCTION IS COMPLETED,THE TEMPORARY / NINON
SEDIMENT BASIN IS TO BE CLEANED UP AND SHAPED
PRIOR TO USE AS AN INFILTRATION BASIN.
INFILTRATION BASIN PLAN VIEW
SCALE:1"=30' 0 30 60
HORZ.
SCALE FEET
2'X 2' CONC. 8"PVC PLUG
ANTI-SEEPAGE 8" PVC PIPE FOR DRAW SCREW TYPE
COLLAR DOWN ORIFICE
SEE DETAIL INV=422.00',SEE DRAW
DOWN ORIFICE DETAIL
8"PVC
TEE
8" PVC
INV OUT=421.75'
3'MIN. 1 8"PVC PIPE N
STUBBEDINTO Z
OUTLET RISER
1 4'MIN 0_
CUTOFF TRENCH I KEY �1 �8"0 DRAW DOWN a
APPROXIMATE SIZE ORIFICE M
EXCAVATE AND BACKFILL WITH LJJ
COMPACTED FILL AS DIRECTED
BY GEOTECHNICAL ENGINEER Z
O
DRAW DOWN ORIFICE DETAIL
SCALE: N.T.S.
CUTOFF TRENCH - OUTFALL DETAIL
SCALE: N.T.S.
J_
L.L
Z
2' J —
12"
1' Q W
#4 REBAR IN FRONT &REAR FACE FLOW PUMP Q
a OF COLLAR.REBAR TO
HAVE 3" MIN.CONC.COVER
a a FROM EDGE OF FACE OF COLLAR \ 0 O
VJ
a
° ° ° ° a .0Gli
a Z <
,�
a a \ WATER LEVEL v , U
a
a a ^
° a NOTES:
1) ALL CONCRETE TO BE 3000 PSI NOTES: �� r••�
2' a a NON-FLY ASH 1) PRIOR TO INSTALLATION, MANUFACTURER SPECIFICATIONS / O z
a 2) APPLY 1/2"THICK WRAP OF OF FILTER MEDIA SHALL BE REVIEWED TO ENSURE THAT
ASPHALTIC CEMENT AROUND DISCHARGE FROM FILTER MEDIA SHALL MEET OR EXCEED
a DISCHARGE PIPE 6"BEYOND PLANNED THE PROVISIONS OF THE CLEAN WATER ACT.
a SEEPAGE COLLAR ON BOTH SIDES 2) ENSURE THAT PUMP PRESSURE DOES NOT EXCEED FILTER _ z
a ° a a 3) APPLY ADDITIONAL ASPHALTIC MEDIA PRESSURE RATING. — / ` a -:)
1' a a a a CEMENT AT PIPE/SEEPAGE COLLAR 3) FILTER MEDIA MAY BE, BUT NOT LIMITED TO,SAND MEDIA �����j ������� 1
a INTERFACE ON UPSTREAM FACES FILTRATION PRACTICES. Q O
4) TO BE FIELD INSPECTED BY 4) PUMP STRAINER SHALL NOT BE IN CONTACT WITH BOTTOM J U
17 GEOTECHNICAL ENGINEER. ASPHALTIC OF POND.
Z] a ° a a CEMENT TO MEET OR EXCEED LOW POINT J
° A FEDERAL SPECIFICATION SS-153 TYP1: J W w
ASTM-D-2822-75 TYPE 1. z
U_ r••� OE
CONCRETE ANTI- SEEPAGE COLLAR INFILTRATION BASIN DEWATERING z O =
SCALE: N.T.S. SCALE: N.T.S.
DESIGNED BY.- JEH
DRAWN BY.- JLF
APPROVED BY.- JEH
SHEET
SM.: REVISION DESCRIPTION: DATE: C3 . 0
1 REDUCED BASIN SIZE PER NCDEQ4/10/24 COMMENTS 4/22/24 CIVIL