20052107 Ver 3_More Info Received_20101221

WITHERS & RAVENEL
ENGINEERS 1 PLANNERS I SURVEYORS
December 17, 2010
Mr. Ian McMillan
401 Oversight/Express Review Permitting Unit
Wetlands and Stormwater Branch
NCDENR - Division of Water Quality
2321 Crabtree Blvd; Suite 250
Raleigh, NC 27604
Re: Creekside at Olde Carpenter
DWQ Project #05-2107
Corps AID #SAW-2009-02322
Mr. McMillan:
05-g-?olV3
Rim[NOWIMB
DEC 2 1 2C10
DENR - WATER QUALITY
VIVI OANDM MwATERNWO
This letter is in response to you Request For More Information letter, dated November
17, 2010 for the Creekside at Olde Carpenter project.
1. Per the requirements of the Neuse Riparian Buffer Rule, all stormwater drainage from
this site must be discharged through a correctly designed level spreader. Level spreader
design requirements are set forth in Chapter S of the North Carolina Stormwater BMP
Manual. A Town of Cary Stormwater Approval does not indicated that diffuse flow
requirements have been met. If you fail to provide an appropriate diffuse flow plan in
your resubmittal, then your project will be returned.
A BMP Detail plan has been enclosed with this letter.
Please feel free to contact me if you have any questions or require additional information
to complete you review.
Sincerely,

Troy Beasley
Environmental Scientist
1410 Commonwealth Drive, Suite 1o1 Wilmington, North Carolina 28403 tel: [phone] fax:[phone]
www.withersravenel.com
/ \ ` OUTLET STRUCTURE GENERAL NOTE RAL NOTES
ELEMENTS INTO RISER STRUCTURE ARE CRITICAL AND SHALL BE INSTALLED
E ELEVATION SHOWN. ~ ~
ToP of onroi 1 . ELEVATIONS OF FLOW ELEMENT ELEV. as sNOwN ~ENCrH ns sHOwN oN P~nNS WITHIN 0.02' OF THE ELEVAT
oN P~aNS ToP of wEiR ELEV. as / z. SLOT FOR OUTLET PIPE SHALL PE SHALL HAVE~A VERTICAL PLAY OF 0.3' TO ALLOW FOR VARIATION IN ELEVATION
2 sHOwN oN PLANS 2~ _ \ OF OUTLET PIPE. THE EXCESS E EXCESS AREA OF THE OPENING SHALL BE FILLED WITH CONCRETE DURING THE INSTALLATION. 16I C~
~~l ;
~ T ~ ~ ' ~ 3. RISER SHALL HAVE A TRASH R TRASH RACK INSTALLED OVER TOP AND WEIR ON SIDE. MAXIMUM OPENING SHALL BE 6"x6". end Ass®~~~~~s
'tT ~'r,C- 1 ~ Ir~ • ' 18" CONCRETE WEIR . l
X75 Walnut Street 10' EL. 345.00
S T WEIR CROSS-SECTION ALONG DAM = e ~ t ~(`~nC 1 ~ ~ ~ ~ EMERG. SPILLWAY EL. 344,00 Suite 36®
LEVEL SPREADER CONCRETE Q ~4 ~}--i~ °"-~J ~ ~ ~ -___________________________1ST 1'mmSTORAGE_ Cary, NC 27511 ~•ti BUSINESS LIC. C-496
UP (ELEVATION SHOWN ON O~O r..` ^ ^ RS,P
PLAIDS) 1 1 ? ~ U Phane~ X919) -1101
CNANNEI TO 8E 6" SOW PATM 3~ LAYER OF ~ J RMAL P00 EL. 342.00 Fal(~ X919)460-7637
DEEP AND 1' IN VADTH ~'J ~ STONE ~~fl { J` 10:1 FIl7ER STRIP - J ~ 6" GATE / 4' 1
u? FOREBAY 5 ~ VALVE ~ ~ i~ ~i
- ti'I BOTTOM OUTLET PIPE
- 3' WIDE STRIP OF Q 3 6.. ~ FILTER FABRIC ~ ~ 4~ EL. 337.00 ~ ~ EL. 337.00
4' SI.OTiED CORRUGATED O 2/ _ J 4_ PLASTIC VNDERDRAIN CONCRETE FOOTER ~(/PO)/- ~ Y ~ I, I FOREBAY DIVIDER CONC. ANTI-SEEP COLLAR INV, 336.49 ~ a i
,8° - 3q3 ~4 WITH CLASS AS NOTE: USE #57 STONE OVERLAID CROSS-SECTION THROUGH DAM 5.5 x 5.5 x 8 THICK z as ai I { ! ~ ~ ~ ~ ~
TH CLASS ARIP-RAP 12" THICK ~ ~ ( , NOT TO SCALE o mom mf i ~ ~
LEVEL SPREADER INSTALLATION W1LL / 1 BE DONE BASED ON THE CURRENT G~' n l~ _I ~ ; ~ _ i I I
DWQ DESIGN GUIDELINES. Pv '3 Q~ ~I
{ , I iii
LEVEL SPREADER DETAIL ~ ~ 4 r?~~ ~ TRASH RACK DETAIL _ i N.T.S. 1 10 TOP OF DA~h345.00 ~
~ I STORAGE FOR 1ST 1" OF AUNOFF ~
6~ . 400 YR. -343.96 ~ I ~ ~ ~ ~ _ . ~ ~ - ~ - -----9.ST. 1" ~ I
z 3' I ~ i
ti F~~~ 345 34~- s° ~ i i •":6" ~ '
0 TOP SHELF 342,50 ~ ~ ma ( {
"~R ~PO~~ , 1~ . \ ONG qE pp ~ / 1'r OR MORE 1. N. P,- 342.00 ° ~
~Q~ _.---_342' S EL` _ 34 ~ s °auc~uRE TRnsH Ra Q / 342 ~ BOTTOM SHELF 341.50 '
-TRASH RACK NORMAL POOL ti ~ ~ o a I I~ ~ w°°w~ ! I~ I i~I
/ Q~ ~ ~Pj _ ~ STRUCTURE SEDIMENT STORAGE ~ I 1 1' 5TORAGE zoo ~ ~ ~ ~ I ~ I
BOTTOM 337.00 ~ ~ I I I I i ~ i H ~ ~ d
/ -341 ~ ~ I m RETEN110N POND CROSS-SECTION ~ z Z p j ~ ~ ~ ~ ~ I,
>~~ti iii E~Z f I
~ TRASH RACK NOTES NOT TO SCALE w w I ~ I ~ I I ~
3E 6" CLEAR OF STRUCTURE TOP~AND aa" ~,~il ~~''ll
~ ~ 1 SIDES.RBOTTOMASHABL BE 1~ i~Q~~ ~ ,~PZ / 3~9 ~ PRPEH RACK NEED NOT COVER ,L BE 1" OR MORE BELOW SLOT. THE ""a ~i~ " I, i;,,;, ~ I
)T COVER THE TREATMENT OUTLET '~I~'~~I ~
TREATMENT ° ° I ; ' ~ ! ~ ' i " I I
j' / 337 m 2. TRASH RACK SHALL BE FASTE ~ ~ / ~ ~ ~ m Q I / STRUCTURE AT AT LEAST 2 P REMOVED FOR MAINTENANCE O y~~0= / / / / ~ m I m ~ STRUCTURE. 3E FASTENED TO EACH SIDE OF THE OUTLET { ~ i j ~ ~ I ~ I I I I
.AST 2 POINTS. IT SHALL BE EASILY SIDE C F~PEE TMENT OUTLET ~ ~ ~ ~ ~ i ; ; ; i I~
=NANCE OR ENTRY INTO THE m o a T ` ~ i ~Tl-~i~j o il~li ;
¢moo ~1~ ii~l~il
3. TRASH RACK SHALL ACCOMMOO gti / AN OPENING. ACCOMMODATE VALVE SHAFT THOUGH I ~ ~ ~ 6" POND DRAIN 5' ° ~ o ~ I , ~ ~ I ' j ' ; ~ _ _ ~ i I_
~ OS1 r 4. TRASH RACK SHALL BE MADE 0 = / m MATERIAL WHICH WILL NOT R ~ ~ / I ( / m I SUNLIGHT AND IS ACCEPTABL / 5. MAX. OPENING IN TRASH RAC Q 6. TOP OF TRASH RACK SHALL H / ~ ~ / ~,I Itrl j- (MAX. 6"X6") .
3E MADE OF DURABLE ~ ~ o cum ; ~ I j( I i _L NOT RUST ,OR DETERIORATE IN z I i!~I:lii ,
;CEPTABLE TO THE TOWN OF CARP. ~ 6" GATE
SASH RACK SHALL BE 6"x6" . o VALVE ~
SHALL HAVE A GRID OF BARS ~ a OUTLET PIPE, SIZE
gq`g44q AiM1t81,~I ~ AND MATERIAL q 'Rr
N d SIDE A DRAINAGE SCHEDULE e,~~°~~ p°,°e~.~Q~.d
WE3R OPENING ANTI-SEEP COLLAR, „ 4"~.,~";'~• a Q~~',. 09-SB-001 PLAN VIEW SIZE 5.5 x 5,5 x 8 THICK b~ ~ :
3 37.0 0 os-se-orn ~ ~ % ~ / BOTTOM ~ND #1 / m (SHOULD BE PLACED „via o ~ ~
/ ~v is NpRMAL POOL- 342 ~ ~ J APPROVE ~ a 345.00 ,PV CUTLET STRUCTURE OS1 APPROx. IN THE ~ ~ ° MIDDLE OF EARTH
N.T.S, DAM) `s~~?~'°° gyp`°~,~~ d~*
/o` o~ ^ TOP OF DAM- TOWN OF C ~ ~
/ m ~ j ~ nJ / ~ / APPROVED BY DATE NOTE. ed`dj ~°FY~iaoasuU''"~e,40* HAND WHEEL WALL THICKNESS AND
' I ~ J ~ PLANNING DATE (ABOVE TRASH RACK) i I REINFORCEMENT DESIGN TO BE
~ / ~ P I DETERMINED BY PRECAST o
/ ~ r ENGINEERING DATE `fi L _ I CONCRETE MANUFACTURER a
0
/ gOREBAY DIVIDER j / ~ i BRACKET
~ TOP TOP OF THE TEE SHALL HAVE A PLUG OR ~i
~ i r / CAP CAP THAT IS REMOVEABLE FOR MAINTENANCE ~
/ - \ / ~ w ~ SHAFT =.:M~ STANDARD MANHOLE STEPS AT ~ ~ 16" O.C. SHALL BE PLACED ABOVE T
~ j / ~ ~ w TREATMENT OUTLET 1" DIA. _ OUTLET PIPE ON OUTSIDE OF STRUCTURE ~
O~ o~ PIPE INV.-342.00 'y.~.. OUTLET LENGTH PER
~ ~U o? 3» DRAINAGE SCHEDULE ~
' ~ ~ a 3" TREATMENT OUTLET a Q
1 ~ \ ~ ~ I m / zv~ _ ~ ' PIPE TO LEVEL SPREADER a cn ~ Z
I ~ ~ ~ ~ ~ m U} j
~ 6" POND DRAIN 6" GATE ~ ~
- ~ I TREATMENT OU / p P ~ ~ - m ~ / N.T.S. POND DRAIN VALVE ~ ~ SENT OUTLET DETAIL ELEV. 337,00 A GROUT N Q
BOTTOM I ~ ~ U N, T. S.
\ ~ NOTE: POND BOTTOM SLOPE FO GRAIN ! ~ _
J ~ - ~ PVC NOT ACCEPTA S ~ , OR OTHER MATERI \ ~ p \ ~ W~ / TO THE TOWN OF ~ s 'OT ACCEPTABLE. USE GSP _ _ , ~ i'-------~- ~ ~ 1 I o d ~ 'HER MATERIAL ACCEPTABLE ~-u' ~ . ro4
E TOWN OF CARP. - ' - ~
I' ~ " 6.:1~ OUTLET PIPE c~ tl Q Z 30" RCP o ~ y=
~ i,T-~~ ~
`7 i _ THICKNESS 36" (MIN. FOR CONCRETE BOTTOM ANTI-SEEP COLLAR, SIZE ~ ~ ~ z
\ U' \ ~OREBAY 10 ~ / LISTED ABOVE L ~ ANTI-FLOATATION) CROSS SECTION O
4 U
p~ OUTLET STRUCTURE OS1 ~ W
u~ ~ _ n \ N.T.S. r-, ~
Q
n ~ . 338 D \ - TOP ELEV. -TOP ELEV.
w 343, 50 I ~ 343.50 ~ y
I
U' ~ N 340 \ n
~ ~ .
WEIR ELEV. 343.19 ~ r,~ WIDTH 6" " ~ ~ ~ ~,s
/ , ~ 341.5 ~ 342 ~ i : ~
J 11,!
4 ~
2 Q
% ; ~._--342.5/ 344 4' J08 # 6062.05
~ OSN/CHK BY: PNJiPNJ _
DWN BY: BAH
~ ~ ~ DATE: 11/12/2009
345 ~ ~ / ~C v HRZ SCALE: 1"=40'
o tirnT crni c• ninnic
POND B+ POND BOTTOM POND BOTTOM
345 346 r7 vn ~~H~~. vvw~ SHEET NO
V i I I N
i"=10' GRAPHIC SCALE V
348 r -
350 V ELEVATION A ELEVATION C °
0 g0 2Q 30 OUTLET STRUCTURE OS1 OUTLET STRUCTURE OS1
N.T.S. N.T.S. G