SW6210702_Plansheet - Walters Meadow_20210803 (10)

C
RIP-RAP PRE-TREATMENT L U Z
FOREBAY AT PIPE INLETS J C�
SEE DETAIL THIS SHEET REMOVABLE CAP _.,
TOP OF EMBANKMENT = 362.0 6" SCHEDULE 40 PVC, SDR35, OR SMOOTH WALL C)
100-YEAR STORM ELEVATION = 361.68 .�.':<.:r i�%�"\•'+W ti%j �4Y\\}j� \\`�// CORRUGATED PLASTIC PIPE WITH 3/8" PERFORATIONS W
STORMWATER MANAGEMENT NOTES: \\�i,\,,\�, /, GRASS SOD \`� /�`�`\/�`/'\ 6" ON CENTER (4 HOLES PER ROW) zL
1. THE DEVELOPER OR HIS AGENT SHALL CONTACT THE DESIGN ENGINEER WHEN THE SPILLWAY ELEVATION = 360.1 \4 /\ •
/ \ A „ FLUSH WITH PAVEMENT IN
BEST MANAGEMENT
PRACTICE(S)ARE
DETERMINEME EXISTING GRADE = 360.0 10-YEAR STORM ELEVATION = 360.07 ti\r\ .\��`�\,\• , FILTER FABRIC AT BOTTOM \\'�\'%//\\/ / PERMEABLE PAVEMENT AREAS \ 7 Q W
CAN BE \ \' \r AND SIDES OF CLEAN SAND i/%///Y`\'Y�/f / I E-'
COMPLIANCE WITH THE APPROVED PLAN CAN BE PERFORMED. f/,/l//\j\/j J+ 4 ' \�.\\`�r` /\r\ w/
2-YEAR STORM ELEVATION = 358.22 \j\\/.`�\\\ <'f 14/ . "4 ✓ //�\//���\/ / °°o li C!�
2. ANNUAL MAINTENANCE INSPECTION AND REPORT REQUIRED - THE OWNER OF A \'/ f/\'/ /,\�' VNVA1 W ✓,,,, ff%%,/\` `/�`1/�A\/' o°
PERMITTED STRUCTURAL STORMWATER BMP CONTROL SHALL ANNUALLY SUBMIT A `//,//�\'/`\/\y /` �M 1'-0" CLEAN SAND !1� \\/ \/`\.s.W o°o a I-
/ 1-YEAR STORM ELEVATION = 357.75 \ \/ /\` \`"�;},,;>`r°,�/\\\` ''�\V \\ / ,s,'•
MAINTENANCE AND INSPECTION REPORT FOR EACH BMP TO THE STORMWATER \/� /e/ r\/\/,,�`%/ � /� '�\N.‘ �\. \ \/\\/'� o 0
ADMINISTRATOR. ANNUAL INSPECTIONS SHALL BEGIN WITHIN ONE YEAR OF THE \\\% \\�"A <\\ \ \/\'+ /'\a* /\/,/\/ f' //\//mil o N
1.0" RAINFALL ELEVATION - 357.01 / 9", /<///// // ` ` \/tip%
RECORDATION OF ANY DEED(S) SHOWING STORMWATER BMPs/CONTROL ✓\ \ \ \ \ \\\\\�\ +1 r ~/ 4I o 0° v'
STRUCTURES. BOTTOM OF BASIN = 357.0 . " `./' /r/\\� ks./.\.\ y ate/J``/\`���\`�f /. ' INFILTRATION �.,
,7'' f /�,'% / '. /,r/f M \ \\/\\/ '\/ SAND MEDIA
3. UPON COMPLETION OF THE PROJECT, AND BEFORE A CERTIFICATE OF OCCUPANCY \ \\` \ \ \ `` ,f / // o°o = .
SHALL BE GRANTED, THE ENGINEER OF RECORD SHALL CERTIFY THAT THE /�/V'/f% �'�\/ ! '' ;' '` ' i ` '1�1/``/\ °o a
FILTER MIXTURE (FROM TOP) `\\\�\\/\f� \ \ ,\l/` ° ° W
COMPLETED PROJECT IS IN ACCORDANCE WITH THE APPROVED STORMWATER //\✓\` \f /\f "; • . I"!•„ , \ `h\/\/\�,/ o°° o
MANAGEMENT PLANS AND DESIGNS. 1'-0" OF CLEAN ASTM C-33 SAND `s` \ \
�j
(MEDIUM AGGREGATE SAND WITH A SIZE ► \ \ �\�\
CONSULTANT:
4. A FINAL INSPECTION OF THE SITE AND STORMWATER MANAGEMENT BMP/CONTROLS 0.02-INCHO -I H °°o
TO BE SCHEDULED WITH AND COMPLETED BY THE PROJECT ENGINEER.
RANGE OF TO 0 4 NC `' 'ges- ,o c'..-„ c:. °
DIAMETER) t +rr' ) .,)t-4''-) °0° 9 9
° ° Triangle Site Design, PLLC
5. NCDEQ AND THEIR ASSIGNS HAVE RIGHT TO ACCESS THE STORMWATER ,,, 4004 Barrett Drive
CONTROL(s) FOR INSPECTIONS OR MAINTENANCE AS NECESSARY. o LAYER OF GEOTEXTILE PERMEABLE ^, UNDISTURBED SUBSOIL
FILTER FABRIC (MIRAFI N-SERIES OR a o „ Suite 101
INTO
o
6. THE ENGINEER'S CERTIFICATION OF COMPLETION WILL BE REQUIRED PRIOR TO THE EQUIVALENT) ;i FILTER FABRIC IN-SITU4SOIL BASE Raleigh, NC 27609
FINAL PLAT OR CERTIFICATE OF OCCUPANCY. THE STORMWATER CONTROL IS TO ® " ( ,: OBSERVATION WELL
INSERT
•
BE INSPECTED TO ENSURE IT IS FUNCTIONING AS DESIGNED AND HAS FULL SCALE: N.T.S. [phone]
N 1 -0 MIN. UNDISTURBED IN-SITU SOIL z= [e-mail]
DESIGN VOLUME PRIOR TO ISSUANCE OF THE FINAL CERTIFICATE OF OCCUPANCY. = c
z �+
11, THE PROPERTY OWNER IS RESPONSIBLE FOR MAINTAINING THE STORMWATER NC License #P-0619
o
CONTROLS(s) ACCORDING TO THE APPROVED MAINTENANCE PLAN AND DIRECTION c
OF NCDEQ. IN o m z
r C
v
s
STORM DRAINAGE PIPE
OR CONCRETE FLUME
SEASONAL HIGH WATER TABLE = 355.0 OUTFACE INTO POND LENGTH & WIDTH .o `N S S o0`,,'G,
DIMENSIONSBE ' /.'j TO
PER RIP-RAP FILTER BED :Quo tigl•.y •
•
APRON DETAIL ELEVATION SEAL '
•
051571
OPERATION & MAINTENANCE PROVISIONS (INFILTRATION) BIO-RETENTION POND r j, •.�
STORMWATER MANAGEMENT DETAILS
INFILTRATION BASIN TYPICAL SECTION T T - - TAPER DEPTH "ii �'�:;ticl'E`,,- Qom;
BMP element: Potential problem: How to remediate the problem 1 T ° . .'
II I . =� I ,� �.
The entire infiltration basin Trash/debris is present Remove the trash/debris NOT TO SCALE NTS #I�1j'_ FOREBAY t >° , ° •#1 4 --F eP,`
The grass filter strip or other pretreatment Areas of bare soil and/or erosive gullies Regrade the soil if necessary to remove .,� s► °°�°°� °°°°°o°°°°°°°°,�
F r • T �.o°c°o°°°a°n°°Ou°°O°a°o a
area have formed the gully, plant ground cover and water 'x lift, lb °°°°°°°°°°°°ogogog°°°°°,;
until established. Provide lime and a 7°°°°°°°° °°°°°°° ° °
i o°o°°oaoo°°°ao°®Qo,°,a+
one-time fertilizer application '41 ( " E----1,---,i0 ;, if=E i7'°g°°s'a°°°`°c°°o°°ae:7
Sediment has accumulated to a depth Search for the source of the sediment and 6" CLASS B OWNER/DEVELOPER:
greater than three inches remedy the problem if possible. Remove
the sediment and dispose of it in a RIP-RAP
A
location where it will not cause impacts RIP-RAP FOREBAY FILTER FABRIC Lee Humphrey
SCALE:to streams or the SCM Double D Engineering,PLLC
S.
ge Street
The flow diversion structure (if applicable) The structure is clogged Unclog the conveyance and dispose of any C ( �r 1 SoOuthern a Pines, NC 28387
sediment in a location where it will not )
cause impacts to streams or the SCM \ ) / a�1 f` I ( 910-684-8646 (Office)
� // / (( , / FILTER MEDIA (SEE NOTE 2)
The structure is damaged Make any necessary repairs or replace if J ( / 1 �t`r^ SILT FENCE AS NEEDED PUMP 910-206-1808 (cell)
damage is too much for repair 1 I \ Cr- AJ ` M j��.� n /\ \ rFLow [e-mail]
1 �/ r\ 4\' V\ ` 1 I /l1 t fC
The inlet device The inlet pipe is clogged (if applicable) Unclogthe pipe and dispose of any -' " A-
-
P P 99 PP ) P P P \2 ,� �� 1 / \) \ \J \ _
sediment in a location where it will not \ ` / r L / -� � , --
/ e sym .....s4 iiiii 11
cause impacts to streams or the SCM / ` l 4 \ _/ ,................
The inlet pipe is cracked or otherwise Repair or replace the pipe ` /)� �� J `� f �' 'II ' WATER LEVEL
damaged (if applicable) / / \ r I / ✓ '
( •,\ NOTE: 111
Erosion is occurring in the swale Regrade the swale if necessary and r' /'�`/ \ I. PRIOR TO INSTALLATION, MANUFACTURER SPECIFICATIONS OF FILTER MEDIA SHALL
(if applicable) provide erosion control devices such as // r BE REVIEWED TO ENSURE THAT DISCHARGE FROM FILTER MEDIA SHALL MEET OR -
reinforced turf matting or rip-rap to avoid r 7/ / EXCEED THE PROVISIONS OF THE CLEAN WATER ACT. -L
future erosion problems / / \ ��f L -1_ 2. ENSURE THAT PUMP PRESSURE DOES NOT EXCEED FILTER MEDIA PRESSURE RATING.
Stone verge is clogged or covered in Remove sediment and clogged stone and / I'�i -/ _1 / 3. FILTER MEDIA MAY BE, BUT NOT LIMITED TO, SAND MEDIA FILTRATION DEVICES, 11 y /11117
sediment (if appliable) replace with clean stone 99 / r ' V ( J - ) RATED FILTER FABRIC BAGS OR POLYMER BASED DEWATERING PRACTICES. _ Q
/ / STORMWATER \ / / 4. PUMP STRAINER SHALL NOT BE IN CONTACT WITH BOTTOM OF POND.
The basin More than four inches of sediment has Search for the source of the sediment and ( 7 `/ MANAGEMENT ) INFILTRATION BASIN DEWATERING LOW POINT
accumulated remedy the problem if possible. Remove \ \ \ EASEMENT / ( / U
the sediment and dispose of it in a / 1 0 z
location where it will not cause impacts
to streams or the SCM f✓ \ I / /
r ( ) Lli I- (-
Erosion of the basin surface has occurred Provide additional erosion protection such �� / /
or riprap is displaced as reinforced turf matting or riprap if ( TOP OF EMBANKMENT Z \ / / z
needed to prevent future erosion problems )7 ELEV=362.0 Q
�• f L I0.° )
q�' \ \ FLOW LONG. TOP OF EMBANKMENT � CD
Water is standing more than three days Replace the top few inches of soil to see .. ) / j / ° \ / SPILLWAY Q(100) SLOPE(%) H B yy SS CHANNEL LINING ELEVATION SPILLWAY ELEVATION Uafter a storm event if this corrects the standing water problem. I/ INFILTRATIONSTRAW WITH NET I I
If not, consult an appropriate professional /\ �C0�' ) SPILLWAY 51.59 CFS 3.33 1.9' 10' 21.4' 3:1 NAG SHOREMAX 362.0 360.1 �_ CD LJJ
for a more extensive repair ) / �1 GRASS SPILLWAY
` r- ° REFER TO DETAIL ( CLASS C W/ P550 - I Q \�
The embankment Shrubs or trees are growing on the Remove trees and shrubs immediately ` J I ,�C�� ° 4 THIS SHEET _ i r Q A11
embankment ( OBSERVATION WELL \%. \/ 1 W
\\,..
/ +_ / I/ EXTEND LINING TO EXTEND LINING TO =
An annual inspection by an appropriate Make needed repairs immediately / ° �� �. TOP OF SPILLWAY TOP OF SPILLWAY TOP OF EMBANKMENT=362.0
professional shows that the embankment •0 •
needs repair 0 �`. �. / =
H CHANNEL LINING
The outlet device Clogging has occurred Clean out the outlet device and dispose of ° •� SS 5`'
sediment in a location where it will not 0 �r / SPILLWAY ELEVATION=360.1
cause impacts to streams or the SCM o 0 �� MATTING SHALL BE AS This document, together with
�� �� / NOTED OR APPROVED EQUAL B { 9
1 the concepts and designs
The outlet device is damaged Repair or replace the outlet device ,", \ 1 GRASS SPILLWAY DETAIL P
�� o `� resented herein, as an
The receiving water Erosion or other signs of damage have Repair the damage and improve the flow ,� o ! / instrument of services, is
P 9 P 0 �• o GRASS SOD ON SPILLWAY intended onl for the s ecific
occurred at the outlet dissipation structureV o ` ' Y Po AND SIDE SLOPES purposeand clientfor which
Discharges from the infiltration trench are Contact the local NCDEQ Regional Office �` ° irTh it was prepared. Reuse of
causing erosion or sedimentation in the r ° / r ( and improper reliance on this
receiving water '( I ti° documentwithoutwritten14
f- o \\? ` °1authorizationandadaptationOPERATION AND MAINTENANCE ( o (�� LbyTrianglesiteDesign, PLLCSTAGE/STORAGE TABLE shall be without liability to
North Carolina storm water rules require quarterly inspections by the regulating agency of infiltration areas as a minimum. More / ° 1 ° INFILTRATION BASIN Triangle Site Design, PLLC.
frequent inspections by the land owner or system operator are strongly encouraged to ensure the proper operation of infiltration (/ (� 1areas. \ ° ^ �� / 1 1 ° STAGE ELEVATION CONTOUR INCREMENTAL TOTALA. Rainfall Event / / ) ti /o/ \\ a (FT) (FT) AREA (SF) STORAGE (CF) STORAGE (CF)1. Inspect the basin after every rainfall event greater than 1.5 inches. \eQdJI ) o / 0.0 357.0 34050 0 0
B. Monthly Inspection ���° f' / \ 1.0358.0361503510035100
1. Inspect the basin monthly T
����� / \ / 2.0 359.0 38320 37235 72335
2. Check the infiltration area side slopes; remove trash and repair eroded areas before the next rainfall event. ; 1�a o / 3.0 360.0 40535 39428 111763
3. Check the vegetative and rock filters for sediment accumulation, erosion and proper operation of the flow spreader 1 1 / �� / 4.0 361.0 42810 41673 153435
mechanism and repair as necessary. � \ /` _ / `( �( .�• • o �> V 5.0 .562.0 45145 43978 197413
C. Quarterly Inspection �" y,,..,\
� , r .> ' L • C 0 7
1. Inspect the collection system (i.e. catch basin, pipes and grass swales) for proper functioning. Clear accumulated Ni\\�/' �, 4., (/�0 :.� ° \ -
trash from basin grates and basin bottoms. Check piping for obstructions. o.• 0
2. Check pond inlet pipes for undercutting, replace rip-rap and repair broken pipes. > o ( \ / \
3. Reseed grassed swales, including the vegetated filter if applicable, twice a year as necessary. Repair eroded areas • �TORMWATER MANAGEMENT DESIGN
immediately. / ° , • J J
D. Six Month Inspection \ . \)�-K> y 1\ \ / 7r ` INFILTRATION BASIN
1. Remove accumulated sediment from the bottom of the outlet structure or other areas where accumulated sediment is • o C / \
noted. \ o o \ J L ` RIVER BASIN: LUMBER
2. Inspect the embankment taking note of any wet areas where water may be seeping through the soil. \ \t•\%, J .\ \/f RECEIVING STREAM: BUFFALO CREEK
E. General Inspection / / \'\ V \ / STREAM INDEX: 14-2.5 0
1. Maximum grass height is to be bin. / , ) 1 �� 1 o2. No woody vegetation shall be allowed to grow in the infiltration area. \ \ ° ' , STREAM CLASS: C3. Debris shall be removed from blocking the inlet and outlet structures and from areas of potential clogging. `•♦ STORMWATER �' HUG: 03040203
4. Periodic removal of dead vegetation shall be accomplished. \ \ MANAGEMENT \ (� Z
5. All components of the infiltration system must be kept in good working order. / •� / v / \�/ EASEMENT / , POND DESIGN SUMMARY �' 2
\ / \� \ DRAINAGE AREA TO POND: 25.74 ACRES
�.��_ 7 c
CRASS
SOD NOTE: J L (� \ �ao I ) / �` / / \ � SITE IMPERVIOUS AREA TO POND: 7.02 ACRES
ASS SOD SHALL BE EITHER HYBRID BERMUDA GRASS OR CENTIPEDE THAT HAS BEEN GROWN IN A SOIL 7 l�./` v 1J r / �� OFF-SITE DESIGN IMPERVIOUS AREA TO POND: 0.34 ACRES Drawn
.)
AT IS FREE OF AN IMPERMEABLE LAYER (SUCH AS CLAY). ( _ �\/ /./(
/t__? r2y,' 5�� / / TOTAL DESIGN IMPERVIOUS AREA TO POND: 7.36 ACRES Checked
✓ ,/ � Approved
•
PRE-DEVELOPED POST-DEVELOPED POST DEVELOPED
(-NOTES: ( �! 34‹I ✓( �� - . C`� / 7 a© THROUGH POND PPrject No: July t044, 20161. ALL INFILTRATION BASINS SHALL HAVE AN ACCESS EASEMENT CONNECTING TO A DEDICATED PUBLIC RIGHT OF WAY. /� . C 1 DRAINAGE AREA: 25.74 AC25.74 AC
, \ \ �) CURVE NUMBER: 58.4 70.9
2. ALL DRAINAGE AREAS TO AN INFILTRATION BASIN ARE TO BE STABILIZED PRIOR TO INSTALLATION OF SOILS OR GRASS SOD. \ ,� \,v ��z Title
21
V /J ` \ / / \ r� J INFILTRATION RATE: 4.5 IN/HR
3. THE DRAINAGE AREA OF THE INFILTRATION BASIN WILL BE CAREFULLY MANAGED TO REDUCE THE SEDIMENT LOAD TO THE SAND FILTER SYSTEM. / \ / ) \ \�n/ / ` _ STORMWATER
4. THE WATER LEVEL IN THE MONITORING WELL(S) WILL BE RECORDED ONCE A MONTH AND AFTER EVERY STORM EVENT GREATER THAN 1.5 INCHES. \ \ / 1.0" STORM EVENT: 0.136 CFS 0.000 CFS
/ \ \ GRAPHIC SCALE 1-YEAR STORM EVENT: 3.237 CFS 33.94 CFS 0.000 CFS CONTROL
\ / \ \ 30 0 15 30 2-YEAR STORM EVENT: 7.967 CFS 51.83 CFS 0.000 CFS
5. IMMEDIATELY AFTER THE
ESTABLISHED (COMMONLYI SIX WEEKS) BASIN IS ESTABLISHED, THE VEGETATION WILL BE WATERED TWICE WEEKLY IF NEEDED UNTIL PLANTS BECOME l ',v-1 7 J / \ / ` \ `` / \ MEASURE DETAILS
l ` 10-YEAR STORM EVENT: 28.20 CFS 107.12 CFS 0.000 CFS
f i, ,. ( . \ t , J 1111.11111
100-YEAR STORM EVENT: 71.93 CFS 207.83 CFS 51.59 CFS
6. NO PORTION OF THE INFILTRATION BASIN WILL BE FERTILIZED AFTER THE INITIAL FERTILIZATION THAT IS REQUIRED TO ESTABLISH THE VEGETATION.
Sheet No.
1 INCH = 30 FEET
7. THE VEGETATION IN AND AROUND THE BASIN WILL BE MAINTAINED AT A HEIGHT OF APPROXIMATELY SIX INCHES. PLAN VIEW
S C 1
`.. / . J
I

RIP-RAP PRE-TREATMENT W Z
FOREBAY AT PIPE INLETS J CJ
TOP OF EMBANKMENT = 364.0 SEE DETAIL THIS SHEET REMOVABLE CAP
I
i r 6" SCHEDULE 40 PVC, SDR35, OR SMOOTH WALL (I)
1TO R M WAT E R MANAGEMENT NOTES: 100-YEAR STORM ELEVATION = 363.69 1,, ..-�`\�->, '\ N• M.., y �f /�j\Y\j\\\ \%/��r CORRUGATED PLASTIC PIPE WITH /8" PERFORATIONS W
1. THE DEVELOPER OR HIS AGENT SHALL CONTACT THE DESIGN ENGINEER WHEN THE SPILLWAY ELEVATION = 362.7 v may/ + r \/\� GRASS SOD j1�,�I\/\ ��\\���\i �' ® 6" ON CENTER (4 HOLES PER�ROW) Z
\/ \/ 4 / FLUSH WITH PAVEMENT IN
BEST MANAGEMENT PRACTICE(S) ARE CONSTRUCTED AND ABOUT TO BECOME 10-YEAR STORM ELEVATION = 362.66 '/ \`/\\/' / / /\ /' PERMEABLE PAVEMENT AREAS a W
OPERATIONAL SO A FINAL INSPECTION CAN BE PERFORMED TO DETERMINE /� �\i /f�/ FILTER FABRIC AT BOTTOM \/�' /\\//\�,\\�
COMPLIANCE WITH THE APPROVED PLAN CAN BE PERFORMED. \ \j�'y\\j\°�/`*, AND SIDES OF CLEAN SAND //\\////\/,�\/ 1 F-+
2-YEAR STORM ELEVATION = 361.11 :\\�
2. ANNUAL MAINTENANCE INSPECTION AND REPORT REQUIRED - THE OWNER OF A \\/\\ %,k, /o/ \/....`> / / /,/,� 0 0
Z
PERMITTED STRUCTURAL STORMWATER BMP CONTROL SHALL ANNUALLY SUBMIT A **\/\ // / /\/°'''i y X.,•„.f//\ /\\,/ / °
/ / \/\/ / \/\ \�\ 1'-O" CLEAN SAND / �1 ' \ \ o 0
MAINTENANCE AND INSPECTION REPORT FOR EACH BMP TO THE STORMWATER 1-YEAR STORM ELEVATION = 360.69 +\ \`� \\\,\ \\ \ .r ?/` / / / / /'
Yi%i ;,/% ram/i / i\ *A\� ,`�\\�iX\,„ \/\j \\� . °°
ADMINISTRATOR. ANNUAL INSPECTIONS SHALL BEGIN WITHIN ONE YEAR OF THE \ \\Jr \ \�j\, , �V 1 r-// \//.',;%' �\` /// °0 o N
RECORDATION OF ANY DEED(S) SHOWING STORMWATER BMPs/CONTROL 1.0" RAINFALL ELEVATION = 360.01 \// /\/\�/\// /// // \j \�%�\ �/\�/\/ °o
STRUCTURES. )'\//j�// % %\/j�`�'\/\i� .M y1�'i /\\/\ //\\//\\ /\/'�\ \// � INFILTRATION o LJ
P\/ \l\ \/ f\/ o 0° „''
EXISTING GRADE = 360.0 BOTTOM OF BASIN = 360.0 \ \/\\�j\j\\ \�`` / 1641 r /\;;'f�/ \\ .\ :\\ //\\,\/ SAND MEDIAa
3. UPON COMPLETION OF THE PROJECT, AND BEFORE A CERTIFICATE OF OCCUPANCY �- '� / . l i�'/�//\//\//\//� / ° °0
SHALL BE GRANTED, THE ENGINEER OF RECORD SHALL CERTIFY THAT THE FILTER MIXTURE (FROM TOP) \/ °� \/\\//\\// 'F • ` ;: , „ <' '�l/\//`>`/T\/�%/\\//� /\ o a
._ .,�t r O O LaJ
COMPLETED PROJECT IS IN ACCORDANCE WITH THE APPROVED STORMWATER 1 /j/r�/ ii ;. ��°� �/�\/\\\ \\\
MANAGEMENT PLANS AND DESIGNS. 1'-0" OF CLEAN ASTM C-33 SAND \� ` / _' rf!��; �, \/'\y/j,\ //' //• °0° c
. :
4. A FINAL INSPECTION OF THE SITE AND STORMWATER MANAGEMENT BMP/CONTROLS (MEDIUM AGGREGATE SAND WITH A SIZE °o° CONSULTANT:
TO BE SCHEDULED WITH AND COMPLETED BY THE PROJECT ENGINEER. RANGE OF 0.02-INCH TO 0.04-INCH , 0 0
DIAMETER) Triangle Site Design, PLLC
5. NCDEQ AND THEIR ASSIGNS HAVE RIGHT TO ACCESS THE STORMWATER w LAYER OF GEOTEXTILE PERMEABLE ° e Drive
CONTROL(s) FOR INSPECTIONS OR MAINTENANCE AS NECESSARY. o �+ UNDISTURBED SUBSOIL
Barrett 4004 Barr
FILTER FABRIC (MIRAFI N-SERIES OR 2 o INSERT 4"-6" INTO Suite 101
6. THE ENGINEER'S CERTIFICATION OF COMPLETION WILL BE REQUIRED PRIOR TO THE N EQUIVALENT) FILTER FABRIC IN-SITU SOIL BASE Raleigh, NC 27609
FINAL PLAT OR CERTIFICATE OF OCCUPANCY. THE STORMWATER CONTROL IS TO oOBSERVATION WELL
BE INSPECTED TO ENSURE IT IS FUNCTIONING AS DESIGNED AND HAS FULL 919 553-6570
DESIGN VOLUME PRIOR TO ISSUANCE OF THE FINAL CERTIFICATE OF OCCUPANCY. 3 1'-O" MIN. UNDISTURBED IN-SITU SOIL SCALE: N.T.S.
- g com
<n ?= mlowder®trianglesitedesi n.
11, THE PROPERTY OWNER IS RESPONSIBLE FOR MAINTAINING THE STORMWATER Za. ti o NC License #P-0619
CONTROLS(s) ACCORDING TO THE APPROVED MAINTENANCE PLAN AND DIRECTION '
c
OF NCDEQ. `V No m a
STORM DRAINAGE PIPE
OOUTFALLRINTO ETE FPOND
_ LENGTH & WIDTHLUME s Q� ��
SEASONAL HIGH WATER TABLE = 358.0 DIMENSIONSBE : E'• '' / ,RIPTO :_��o S S I oy.•,
PER RIP-RAP FILTER BED • q
, . ;'. APRON DETAIL
ELEVATION •¢ SEAL
OPERATION & MAINTENANCE PROVISIONS (INFILTRATION) 1 BIO-RETENTION POND ';••Foj/Y •
r STORMWATER MANAGEMENT DETAILS - - - - TAPER DEPTH o
1� BMP element: Potential problem: How to remediate the problem \ INFILTRATION BASIN TYPICAL SECTION I_. ;_,-. ;. 0 GIN. �o,.
fThe entire infiltration basin 1 i I " mho °
Trash/debris is present Remove the trash/debris NOT TO SCALE NTS Y _ - 9 ' FOREBAY t' 1. •E �.
--I
li a 2, ,oi;r.n..►.�
I 34 Imo, 1,
The grass filter strip or other pretreatment Areas of bare soil and/or erosive gullies Regrade the soil if necessary to remove I , It g
� .
area have formed the gully, plant ground cover and water I, L-i'6, °A ° G"
I-4 I- hg.g.g.g.g.2.g?
until established. Provide lime and a .I i T „0 .g.g.gpg.gggg
one-time fertilizer application i Q:_� E i- i Tll i
Sediment has accumulated to a depth Search for the source of the sediment and 6" CLASS B OWNER/DEVELOPER:
greater than three inches remedy the problem if possible. Remove
�/ RIP-RAP OVER
the sediment and dispose of it in a I RIP-RAP FOREBAY FILTER FABRIC Lee Humphrey
lotocation steams whereo the it will SCM
cause impacts RIP-RAP f: D Double DpEngineering,PLLC
SCALE: N.T.S.
The flow diversion structure (if applicable) The structure is clogged Unclog the conveyance and dispose of any Sou S. Page Street
sediment in a location where it will not Southern Pines, NC 28387
cause impacts to streams or the SCM 910-684-8646 (Office)
FILTER MEDIA (SEE NOTE 2)
The structure is damaged Make any necessary repairs or replace if PUMP 910-206-1808 (Cell)
damage is too much for repair SILT FENCE AS NEEDED `
The inlet device I FLOW (C lee®doubledeng.com
The inlet pipe is clogged (if applicable) Unclog the pipe and dispose of any ` r- -
sediment in a location where it will not I / -
cause impacts to steams or the SCM / / \ \ r r -/ J \� \^ - �i0%i0�%%%ii%�:%�-! �'� O�
The inlet pipe is cracked or otherwise Repair or replace the pipe \ / J ' N. S FWATER LEVEL
damaged (if applicable) \ l (-\-`) \ NOTE: II
Erosion is occurring in the swale Regrade the swale if necessary and \ / I 1• PRIOR TO INSTALLATION, MANUFACTURER SPECIFICATIONS OF FILTER MEDIA SHALL
(if applicable) provide erosion control devices such as /( /-/ BE REVIEWED TO ENSURE THAT DISCHARGE FROM FILTER MEDIA SHALL MEET OR
reinforced turf matting or rip-rap to avoid / EXCEED THE PROVISIONS OF THE CLEAN WATER ACT. -
future erosion problems f / ) "--"'ti 1 / /
�� ) �\ / \ \ / < / I - L. ENSURE THAT PUMP PRESSURE DOES NOT EXCEED FILTER MEDIA PRESSURE RATING.
Stone verge is clogged or covered in Remove sediment and clogged stone and z�\�< ( •
\ L / / 3. FILTER MEDIA MAY BE, BUT NOT LIMITED TO, SAND MEDIA FILTRATION DEVICES, I g I
sediment (if applicable) replace with clean stone ( ) (/ -�rl \ STORMWATER S) RATED FILTER FABRIC BAGS OR POLYMER BASED DEWATERING PRACTICES. _ _
MANAGEMENT , �) ) \ 4. PUMP STRAINER SHALL NOT BE IN CONTACT WITH BOTTOM OF POND. III I-
./ ti) \) s r /
The basin More than four inches of sediment has Search for the source of the sediment and `/ / EASEMENT "'
accumulated remedy the problem if possible. Remove �/ L� r / INFILTRATION BASIN DEWATERING / LOW POINT I� U
the sediment and dispose of it in a fa ) / Z
location where it will not cause impacts -.� N,� e's \ / ICI (/)
to streams or the SCM _.-------" / I 0
------ - I Q L i J >-
Erosion of the basin surface has occurred Provide additional erosion protection such - \ , L1J i-- f-
/
or riprap is displaced as reinforced turf matting or riprap if ---' ( ) 1 r _ 1, -
needed to prevent future erosion problems ----�- / \ \�/l � 7_ I.� Q
'� `n --��- I. >1 \ / �` `) FLOW LONG. TOP OF EMBANKMENT V) O
Water is standing more than three days Replace the top few inches of soil to seems -1 OBSERVATION WELLAtk SPILLWAY SS CHANNEL LINING SPILLWAY ELEVATION
after a storm event if this corrects the standing water problem. rt ) (TYP.) ` ` �r N Q(100) SLOPE() H B W ELEVATION U
f �- INFILTRATION 24.90 CFS 3.33 1.3' 10' 17.8' 3:1 STRAW WITH NET 364.0 362.7 W L�J
If not, consult an appropriate professional y L. n l L. / I V SPILLWAY NAG SHOREMAX I--- U W for a more extensive repair
\ \\l / I ( i� r (^'\ / \ CLASS C W/ P300 - <
The embankment Shrubs or trees are growing on the Remove trees and shrubs immediately J� ' / J / Q C
GRASS SPILLWAY
embankment S ( I r r' r W
r o / . , REFER TO DETAIL EXTEND LINING TO ® _
CA y \ 1\4 THIS SHEET 1 EXTEND LINING TO =
An annual inspection by an appropriate Make needed repairs immediately ( \ I la, J o I TOP OF SPILLWAY TOP OF SPILLWAY TOP OF EMBANKMENT=364.0
professional shows that the embankment I
1 N'' /
needs repair , <
)I (, ) �• / H CHANNEL LINING
The outlet device Clogging has occurred Clean out the outlet device and dispose of -.i) TOP OF EMBANKMENT `'' r W / / SS SS
sediment in a location where it will not ELEV=364.0 / 0) / +♦�� 1 SPILLWAY ELEVATION=362.7
cause impacts to streams or the SCM �-"l ( ) o ', -> / MATTING SHALL BE AS
The outlet device is damaged Repair or replace the outlet device \\� �' / M �/ o 44744 i � NOTED OR APPROVED EQUAL. B '� theThisconceptsnand deesignsther ith
/ l GRASS SPILLWAY DETAIL presented herein, as an
The receiving water Erosion or other signs of damage have Repair the damage and improve the flow C ) /I \ ( -' 1 instrument of services, is
occurred at the outlet dissipation structure \ / ( 0 r o / GRASS SOD ON SPILLWAY intended only for the specific
1 <\ h I co J \ J� AND SIDE SLOPES purpose and client for which
Discharges from the infiltration trench are Contact the local NCDEQ Regional Office S. I r�? o 0 / / 1 / it was prepared. Reuse of
causing erosion or sedimentation in the „ /
receiving water / and improper reliance on this
7Ilik111111,111111111111111. ‘- \ >S 1 E i I document without written
� //`J authorization and adaptation
OPERATION AND MAINTENANCE --__ / < a ° / L by Triangle Site Design, PLLC
North Carolina storm water rules require quarterly inspections by the regulating agency of infiltration areas as a minimum. More ) ) ( Z !_.^ STAGE/STORAGE TABLE shall be without liability to
frequent inspections bythe land owner or system operator are strongly encouraged to ensure the proper operation of infiltration STORMWATER < ° / \
areas. p y p g Y g p p p MANAGEMENT / / / / \ INFILTRATION BASIN Triangle Site Design, PLLC.
A. Rainfall Event EASEMENT ` (1 / I / 1>`�) / /.i \
STAGE ELEVATION CONTOUR INCREMENTAL TOTAL /-
/ ) I (FT) (FT) AREA (SF) STORAGE (CF) STORAGE (CF)
1. Inspect the basin after every rainfall event greater than 1.5 inches. 1 ) 1 / / ° 0.0 360.0 11385 0 0
B. Monthly Inspection J / 1 `\r /1/ / /J 1.0 361.0 12740 12063 12063
1. Inspect the basin monthly , / -\ \, 2.0 362.0 14155 13448 25510
2. Check the infiltration area side slopes; remove trash and repair eroded areas before the next rainfall event. i 3.0 363.0 15620 14888 40398
3. Check the vegetative and rock filters for sediment accumulation, erosion and proper operation of the flow spreader ? / ` r 4.0 364.0 17145 16383 56780
mechanism and repair as necessary. y ,� II \ p3C1, tp� / Oj I
C. Quarterly Inspection I l \ o 03�L� �� I _ -
1. Inspect the collection system (i.e. catch basin, pipes and grass swales) for proper functioning. Clear accumulated 1 \ \ �� i I `- Z
trash from basin grates and basin bottoms. Check piping for obstructions. ( \
2. Check pond inlet pipes for undercutting, replace rip-rap and repair broken pipes. \ ) \77 1 / I \\
3. Reseed grassed swales, including the vegetated filter if applicable, twice a year as necessary. Repair eroded areas 1 \ \ /1 \ \ -- I \ I
immediately. / \ (STORMWATER MANAGEMENT DESIGN
D. Six Month Inspection � \ ( S� \ /�� -/ INFILTRATION BASIN
1. Remove accumulated sediment from the bottom of the outlet structure or other areas where accumulated sediment is \ .� \ /- - -' / \ \
noted. \ ( / Z V / \� RIVER BASIN: LUMBER
2. Inspect the embankment taking note of any wet areas where water may be seeping through the soil. ^ _ \ / ' RECEIVING STREAM: BUFFALO CREEK
E. General Inspection t� \ ) /
1. Maximum grass height is to be 6in. I \ \ / / `��, .- / STREAM INDEX: 14-2.5 H
\ \ - / STORMWATER / m
2. No woody vegetation shall be allowed to grow in the infiltration area. c \ \ \ 1 f N / MANAGEMENT STREAM CLASS: C o
3. Debris shall be removed from blocking the inlet and outlet structures and from areas of potential clogging. ( \ ( N _ EASEMENT ( HUC: 03040203
4. Periodic removal of dead vegetation shall be accomplished. N \ / \ / L 1 \ __ - 1 V - rr zen
5. All components of the infiltration system must be kept in good working order. _, �/ z N / \ )1(k
o
1 \ ) /.1 s \ POND DESIGN SUMMARY o
\ DRAINAGE AREA TO POND: 7.63 ACRES
CRASS
SOD NOTE:
~\ \� \ -� // / Ili
SITE IMPERVIOUS AREA TO POND: 2.12 ACRES
ASS SOD SHALL BE EITHER HYBRID BERMUDA GRASS OR CENTIPEDE THAT HAS BEEN GROWN IN A SOIL ( ' � \ / \� OFF-SITE DESIGN IMPERVIOUS AREA TO POND: 0.00 ACRES Drawn
AT IS FREE OF AN IMPERMEABLE LAYER (SUCH AS CLAY). \\ �\ \J� ���- // \r I' 1 r\ \\ ,I / TOTAL DESIGN IMPERVIOUS AREA TO POND: 2.12 ACRES Checked
Approved
(I ( i A LC`L <► -Q
\ \-J \ • PRE-DEVELOPED POST-DEVELOPED POST DEVELOPED
�OTES: ) / ~` -
// I \\ \_ ^ aQ THROUGH POND Project No: 048016
1. ALL INFILTRATION BASINS SHALL HAVE AN ACCESS EASEMENT CONNECTING TO A DEDICATED PUBLIC RIGHT OF WAY. / \ N.
\_k \ ^ \ (.' DRAINAGE AREA: 7.63 AC 7.63 AC Date: July 14, 2021
2. ALL DRAINAGE AREAS TO AN INFILTRATION BASIN ARE TO BE STABILIZED PRIOR TO INSTALLATION OF SOILS OR GRASS SOD. /
�/ / L 1 � / \J v ` \ CURVE NUMBER: 59.3 70.6 Title
/ \ I \ )<T S INFILTRATION RATE: 3.0 IN/HR
3. THE DRAINAGE AREA OF THE INFILTRATION BASIN WILL BE CAREFULLY MANAGED TO REDUCE THE SEDIMENT LOAD TO THE SAND FILTER SYSTEM. / ^J \ `r \ \ \✓ t, ,) \ STORMWATER
// r 1 I 1.0" STORM EVENT: 0.037 CFS 0.000 CFS
4. THE WATER LEVEL IN THE MONITORING WELL(S) WILL BE RECORDED ONCE A MONTH AND AFTER EVERY STORM EVENT GREATER THAN 1.5 INCHES. / \J/ N-J \
_ r ( , GRAPHIC SCALE 1-YEAR STORM EVENT: 1.594 CFS 9.858 CFS 0.000 CFS CONTROL
5. IMMEDIATELY AFTER THE INFILTRATION BASIN IS ESTABLISHED, THE VEGETATION WILL BE WATERED TWICE WEEKLY IF NEEDED UNTIL PLANTS BECOME N c 1 / \ --, I �tI\` I- 1/ r / 30 0 15 30 2-YEAR STORM EVENT: 3.769 CFS 15.12 CFS 0.000 CFS
ESTABLISHED (COMMONLY SIX WEEKS) �/ N
' 10-YEAR STORM EVENT: 12.45 CFS 31.44 CFS 0.000 CFS MEASURE DETAILS
6. NO PORTION OF THE INFILTRATION BASIN WILL BE FERTILIZED AFTER THE INITIAL FERTILIZATION THAT IS REQUIRED TO ESTABLISH THE VEGETATION. l mi 100-YEAR STORM EVENT: 30.27 CFS 61.19 CFS 24.90 CFS
1 INCH = 30 FEET Sheet No.
7. THE VEGETATION IN AND AROUND THE BASIN WILL BE MAINTAINED AT A HEIGHT OF APPROXIMATELY SIX INCHES. J PLAN VIEW
SCE2
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