HomeMy WebLinkAboutWPO201300067 Plan - VSMP WPO VSMP 2015-10-15GENERAL NOTES.
OWNER PER ALBEMARLE
COUNTY RECORDS TMP 03200-00-00-05000
ROUTE 29 LLC
PO BOX 5548
CHARLOTTESVILLE, VA 22905
TMP 03200-00-00-05600
UPTOWN VILLAGE LLC C/O UNITED LAND CORPORATION
PO BOX 5548
CHARLOTTESVILLE, VA 22905
DEVELOPER MR. WENDELL WOOD
2315 SEMINOLE LANE
CHARLOTTESVILLE, VA 22901
ENGINEER COLLINS ENGINEERING
200 GARRETT STREET, SUITE K
CHARLOTTESVILLE, VA 22902
CONTACT: MR. SCOTT COLLINS
434.293.3719
TAX PARCEL # 03200-00-00-05000 (PART OF)
ACREAGE 11.012 ac. (0.75ac. COMBINED WATER SURFACE AREA)
ZONING NEIGHBORHOOD MODEL DISTRICT
PROPOSED USE CONVERT TWO SEDIMENT BASINS TO SWM FACILITIES
DEVELOPMENT DENSITY- N/A
PROPOSED MAXIMUM LOT COVERAGE (IMPERVIOUS COVER)- NO IMPERVIOUS AREAS ARE PROPOSED WITH THIS PLAIN,
HOWEVER BOTH SWM FACILITIES ARE DESIGNED FOR FUTURE IMPERVIOUS AREAS.
PHASING- THIS PLAN, WHICH PROPOSES THE CONVERSION OF TWO SEDIMENT BASINS TO SWM FACILITIES, SHALL OCCUR IN
ONE PHASE.
IAL SURVEYS INC IN JUNE
- BY LOUISA AER
SURVEY PROVIDED
TOPOGRAPHY/SURVEY- TOPOGRAPHY CREATED FROM AERIAL ,
2007. SURVEY INFORMATION PROVIDED BY RIVAN
NA ENGINEERING
&SURVEYING, PLC. TOPOGRAPHY FIELD VERIFIED BY
COLLINS ENGINEERING 2013.
N CENTER DRIVE, ELEVATION 583.
04 SHOWN ON
THIS SHEET.
OF BOX ON TOW ,
BENCHMARK- ARK- EXISTING TOP ,
DATUM- ELEVATIONS BASED ON NAD 83 DATUM.
FLOODPLAIN INFORMATION- THIS PROPERTY IS LOCATED IN ZONE 'X' AS SHOWN ON THE FLOOD INSURANCE RATE M1AP, MAP
NUMBER 51003C0140D, EFFECTIVE DATE FEBRUARY 4, 2005.
STREAM BUFFERS- NO STREAM BUFFERS EXIST ON SUBJECT PARCEL PER ALBEMARLE COUNTY GIS.
WATERSHED- THIS SITE DRAINS TO THE POWELL CREEK WATERSHED.
EXISTING VEGETATION- NIA. TWO SWM FACILITIES PROPOSED ARE CURRENTLY SEDIMENT BASINS.
ACCESS- TOWN CENTER DRIVE SHALL SERVE AS ACCESS TO SWM FACILITIES.
SETBACKS- N/A
MAXIMUM STRUCTURE HEIGHT- N/A
MINIMUM BUILDING SEPARATION- N/A
NO PARKING IS PROPOSED OR REQUIRED WITH THIS PLAN
NO LIGHTING IS PROPOSED OR REQUIRED WITH THIS PLAN
NO SIGNAGE IS PROPOSED OR REQUIRED WITH THIS TIME
SITE AREAS- SEE SWM DETAILS FOR EXISTING & FUTURE IMPERVIOUS LOADINGS
NO CEMETERIES WERE FOUND DURING THE FIELD INVESTIGATION AND SURVEY TOPO AND BOUNDARY ON THE PROPERTY.
CRITICAL SLOPES- NO ADDITIONAL CRITICAL SLOPES ARE PROPOSED TO BE DISTURBED WITH THIS PLAN.
LANDSCAPING IS PROPOSED FOR THE AQUATIC BENCH, WHERE APPLICABLE.
CONTRACTOR SHALL VERIFY LOCATION AND ELEVATION OF ALL UNDERGROUND UTILITIES SHOWN ON PLANS IN AREAS OF
CONSTRUCTION PRIOR TO STARTING WORK. CONTACT ENGINEER IMMEDIATELY IF LOCATION OR ELEVATION IS
DIFFERENT FROM THAT SHOWN ON THE PLANS, IF THERE APPEARS TO BE A CONFLICT, AND UPON DISCOVERY OF
ANY UTILITY NOT SHOWN ON THE PLANS.
COLLINS ENGINEERING SHALL NOT HAVE AUTHORITY OVER CONTRACTOR'S WORK, SAFETY PRECAU77ONS, SCHEDULES, OR COMPLIANCE WITH LAWS' AND
REGULA77ONS, WE SHALL NOT ASSUME RESPONSIBILITY FOR ANY CONSTRUCTION BEGUN PRIOR TO PLAN APPROVAL.
.LEGEND
EARTH DITCH
—1
EXISTING CUL VER T
(�}
Y
CUL VERT
si
A
DROP INLET & STRUCTURE NO.
VDOT STANDARD STOP SIGN
CURB
— EXISTING CONTOUR
6
CURB & GUTTER
200
240.55
PROPOSED SPOT ELEVATION
PROPOSED PAVEMENT
TBC DENOTES TOP/BACK CURB
EC—JA DITCH
0
63,
0 Y
DEPTH OF EC—JA DITCH
_0 °
EC -2 DI TCH
6"
DEPTH OF EC -2 DITCH
HOLLYMEAD TOWN CENTER
Di IT
M__ 49
It Ll
UPTOWN VILLAGE LLC C/O
UNITED LAND CORPORATION
ZONE: R-15 RESIDENTIAL
TMP: 03200-00-00-05600
USE: VACANT
RIO MAGISTERIAL DISTRICT
ALBEMARLE COUNTY, VIRGINIA
APPROXIMATE LOCATION OF
EXISTING ROAD NETWORK
TOWN CENTER DRIVE
60' PUBLIC R/W TO BE
DEDICATED
ROUTE 29 LLC ---___
ZONE: NEIGHBORHOOD MOIDEL DISTRIC-
TMP: 03200-00-00-05000
USE: RESIDENTIAL
D.B. 3801 PG. (609
APPROXIMATE LOCATION CATIO
N OF-
PARCEL OWNIED BY
WILLOW GLE
NA LB
EMARL
E INC
TMP 032KO-00-000DO
EXISTING SEDIMENT BASIN
PROPOSED► TO BE CONVERTF
TO SWM FACILITY #1 WITH
THIS SET OF PLANS
1
TRIBAL PROPERTIES LLC C/0`
REAL PROPERTY INC. j
EIGHBORHOOD MODEL DISTRICT 1
TMP:032BO-00-00-000AO
USE: RESIDENTIAL tr JI
F /
EXISTING SEDIMENT BASIN -
PROPOSED TO BE CONVERTED
TO SWM FACILITY #2 WITH
THIS SET OF PLANS,_,-)
;I
PROJIECT OVERVIEW
SCALE: 1" = 100'
DEVELOPER
MR. WENDELL WOOD
2315 SEMINOLE LANE
CHARLOTTESVILLE, VA 22901
,
\ ABINGTON PLACE @
EARTH DITCH
F
DRIVEWAY CULVERT
(�}
Y
BENCH MARK
si
CLEARING LIMITS
s�
VDOT STANDARD STOP SIGN
— — —2�p— —
— EXISTING CONTOUR
6
PROPOSED CONTOUR
200
240.55
PROPOSED SPOT ELEVATION
STORMWATER MANAGEMENT DETAILS- SWM FACILITY #3
TBC DENOTES TOP/BACK CURB
TAB DENOTES TDP OF BOX
HOLLYMEAD TOWN CENTER
Di IT
M__ 49
It Ll
UPTOWN VILLAGE LLC C/O
UNITED LAND CORPORATION
ZONE: R-15 RESIDENTIAL
TMP: 03200-00-00-05600
USE: VACANT
RIO MAGISTERIAL DISTRICT
ALBEMARLE COUNTY, VIRGINIA
APPROXIMATE LOCATION OF
EXISTING ROAD NETWORK
TOWN CENTER DRIVE
60' PUBLIC R/W TO BE
DEDICATED
ROUTE 29 LLC ---___
ZONE: NEIGHBORHOOD MOIDEL DISTRIC-
TMP: 03200-00-00-05000
USE: RESIDENTIAL
D.B. 3801 PG. (609
APPROXIMATE LOCATION CATIO
N OF-
PARCEL OWNIED BY
WILLOW GLE
NA LB
EMARL
E INC
TMP 032KO-00-000DO
EXISTING SEDIMENT BASIN
PROPOSED► TO BE CONVERTF
TO SWM FACILITY #1 WITH
THIS SET OF PLANS
1
TRIBAL PROPERTIES LLC C/0`
REAL PROPERTY INC. j
EIGHBORHOOD MODEL DISTRICT 1
TMP:032BO-00-00-000AO
USE: RESIDENTIAL tr JI
F /
EXISTING SEDIMENT BASIN -
PROPOSED TO BE CONVERTED
TO SWM FACILITY #2 WITH
THIS SET OF PLANS,_,-)
;I
PROJIECT OVERVIEW
SCALE: 1" = 100'
DEVELOPER
MR. WENDELL WOOD
2315 SEMINOLE LANE
CHARLOTTESVILLE, VA 22901
,
\ ABINGTON PLACE @
Sheet Title
F
\ HOLLYMEAD TC
2
(NOT PART OF THIS SET
si
OST -DEVELOPMENT STORMWATER MANAGEMENT PLAN- SWM FACILITIES #1 & #2
-
OF PLANS & RECEIVES
5
STORMWATER MANAGEMENT DETAILS- SWM FACILITY #2
6
SEPARATE TREATMENT),'
, z`
f
r
STORMWATER MANAGEMENT DETAILS- SWM FACILITY #3
�:7 7
r
0
SCALE
0 Y
_0 °
�j
NIA
p 3
� Q7
J
SHEET NO.
a
;
1
.j
r
d,
s,.
3r
s
t
ENGINEER
COLLINS ENGINEERING
200 GARRETT STREET, SUITE K
CHARLOTTESVILLE, VA 22902
THIS
PROJECT
VICINITY MAP
SCALE: 1" = 2000'
Sheet List Table
zK o
SCOTT R. COLLINSZ
No. 35791
a
Sheet Number
Sheet Title
1
TITLE SHEET
2
PRE -DEVELOPMENT STORMWATER MANAGEMENT PLAN- SWM FACILITIES #1 & #2
3
OST -DEVELOPMENT STORMWATER MANAGEMENT PLAN- SWM FACILITIES #1 & #2
4
STORMWATER MANAGEMENT DETAILS- SWM FACILITY #1
5
STORMWATER MANAGEMENT DETAILS- SWM FACILITY #2
6
PRE -DEVELOPMENT STORMWATER MANAGEMENT PLAN- SWM FACILITY #3
7
POST -DEVELOPMENT STORMWATER MANAGEMENT PLAN- SWM FACILITY #3
8
STORMWATER MANAGEMENT DETAILS- SWM FACILITY #3
1.1
TOTAL SHEETS
W
Ul
Z
I
Z
a �
Li
U) U)w
n
Q�
�z
„ w
o�
z
-'
0
c
o (5)
Q1
c �
Uj o
I.L 2
U) c N
Uj Q
x
U N
F- a
o�
F— Q�
i O
o
o �
E
0
� o
o +,
V
CD
Z +
E
Li
Li °
Z_ V
O
Z
wa
c
Z �
J
J Sz
O -0
O �
O
>'
0- V
0
L
sz
Q c
9 °
•� v
°
U
° v
E
a)
0 0
cnc
v �
LU
>
_0D
JOB NO.
.�
102036
L
U
° j
0
SCALE
0 Y
_0 °
�j
NIA
p 3
� Q7
O O
SHEET NO.
a
0 Q
1
Fn
. . ........ ITIIIR OP E RTY_ '0 0 I77:7 ItIititit... . . . . ...... tto - -------- r7 Irr
iII
F-c 11 ( ,0
•
tt
. . . . . . . . . . DA #:LA: '(AN L r �EDA,� 51_0��,. ...... IgoGRASS
WOODS ^`'. 501, itN' OVEkLAND F OW APPROXIMATE\LqCATIrOIN OF II13.6ac =�oo' C 58.o �Tc=ioi in) 6STING ROADWAYBY (�TERS) TA ELEV.= IC LIN I ANN�L FLO (G�ASS)=1,125'\A�l -------- - A ELEV.�68'(Tc= —:L5 min.. ]ON OF kXISTINGSED1 ITO BE CONE'. 0 I:5 min.) PROPUED �VVIVI,ABILITY #1 IIFINAL TC it min.ITMP 03200-60-00 56c� IIIitIIIitITJWWCZNTBR DRfflE - ----- w X� --- --- ------- tbA/#3.B. ITIac. /9
S.
L.
ro
•
tOVERLAN,D FL6,wrr T w i ELE� -8- (fe,=8 rhin.,)/ EXI�FING SEDIME� -------- �OC 11 F i0- -6TEE�TO LFJ BA511 E CON�E ------ ------- I- - t i 0 CITY # n./) , , pi� A---ELEW=58l(f SV�M ACILI D H A N rf E L FL OW= tc 5 _._iFIN i itI7 .. ...... ... -00-00- TMP 0�200
lq
vy
q o56o If �1 T--------- ------- L IIIi4 7 F tTTV/ t -A - ----- — ----- 100 2ob 4DO 100 ft
100LOCATIO F EX N SE D I MENT 0 0 ISTt N CONYERTED, 0 BASIN 0 PROPOJ SWM i�CJLJTY 3 ED F I/* ``t
II'SUM f
ft r
rr
Short Version BMP Computations For Worksheets 2 - 6
Albemarle (' ounty Water Protection Occlinancea- Modified Simple Method
Plan] ......,,,,Ho]NTeadTc>wnceMer.Water,.Quality Water Re.5ources Area a DewiloprrientAre
.. ....... .. . .
---
Preparer. FGM, PE Date..
Project Drainage Area Designation
L sicirm pultuliant export in pounds, L = [I'(PI)RW112 C(A)2.72 I
Ru man runoffc oefficient, Rv = 005 + 0-009(l)
Pi smal starriq rwerton facia, 09
I per cent irrpetviousr�ess
F annual prer[pitalion, 43" In Albemarle
A protect area in acres in subject dranage areali A= 2221
C pollutant concennt on, 111g,11 or ppm target phosphorus
z
t factor applied to RR
V re qui red trelfrient VOI In e in c y, O_ S' over 1 rnper. area = A(I)4356fJ(0_ 51 Z,V27
RR required renictilial L(pos!]1-fxL(pre)
% RR remGliar efficiency, RRIUGIL�postl
C;6
Impervious Cover Computation (\a lues in feet & square feet)
Item
pre -development iArea post-develc merit . ...... . .
Area
subtotai
UIC Kefson Road 14,250: Credit for Future Deveropinent,'Impery[ous.Areas i
595 000:
rillobile Home ParK Roads 25,700, Exisling'AlHilow Gen In -p. Areas being treated
I2200�
Existing. w
Tricentef Dril,eil3ldewalk being treated
�5j
J Exist ng Dic kerson Road Not being Treated, buit
3g,3m:704,875
. . . . ...... "f�lobileHaTePark Gra,,etDrivc,wv s
V)
16550;x 0.70 I 15.16 :x0.70 .
. ................... . suubtail
SU
3lvlobie Horre Park Buildings
LU
I.
. . ....... ..... fAcfiwlv-gra7ed pasture & Area I Area
trard_, and cultivated turf 830A93�iXO-03= 70j39 x 0,08 -
21,007,
AcIlvecrop land AreaIx'x0.26=
,Other rrpeNIOLIsAreas
ImperviousCover
I pre)
0.72 ....... .
U
Nm,stin 20 %ewD lo FDA easexi
C _!FZv(pre) L(pre) 1 L(post) RR R Area,Type
701.63 48 23' GSY,;� Detif4opment Area
z
_0 Of
W Ld
. . ...........
min. Values
fi
f 11n
ary o ' D.A. #1 B Impervious Areas Existing Roads (paved) 25,700 sf Exisfing.. DrivewaysExisting Buildings 30,475 sf Ex,istinq Dickerson Road 14,250 sf Total 86, sf
SWM NARRATIVE/NOTES:
THE FUTURE DEVELOPMENT WITHIN DA #11S ANTICIPATED TO NOT EXCEED 595,000sf OF IMPERVIOUS
AREA. A FUTURE IMPERVIOUS AREA OF 595,000sf WITHIN DA #i GENERATES A REMOVAL RATE
EFFICIENCY REQUIREMENT OF 68%. TWO PROPOSED SWIM FACILITIES ARE DESIGNED TO PROVIDE
WATER QUALITY TREATMENT FOR THIS FUTURE IMPERVIOUS AREA, THE PRIMARY SWM FACILITY,
FACILITY #:1, PROVIDES A REMOVAL EFFICIENCY OF 65%. THIS FACILITY ALSO PROVIDES ALL OF -THE
DETENTION NECESSARY FOR DA *1 WITHOUT TAKING INTO CONSIDERATION THE DETENTION
BENEFITS FROM SWM FACILITY #2. HOWEVER DUE TO THE 3% WATER QUALITY SHORTAGE, AN
ENHANCED EXTENDED DETENTION FACILITY IS PROPOSED TO PROVIDE SUPPLEMENTAL TREATMENT
TO GAIN COMPLIANCE. THE ENHANCED EXTENDED DETENTION FACILITY, SWM FACILITY #2,
PROVIDES A REMOVAL RATE EFFICIENCY OF So%. ALSO, THE MINOR WATER QUALITY VOLUME
SHORTAGE ASSOCIATED WITH THE 390 OVERAGE FOR SWM FACILITY #3. IS GREATLY EXCEEDED IIN THE
WATER QUALITY VOLUMES PROVIDED WITH SWM FACILITY #2.
BECAUSE IMPACTING THE EXISTING GREENWAY AND EMBANKMENT DOWNSTREAM OF SWM FACILITY #2 IS NOT IDEAL, THE DRAINAGE FROM SWM FACILITY #2 IS PIPED TO THE EXISTING 48" STORM SEWER UNDER TOWN CENTER DRIVE WHERE IT ULTIMATELY OUTFALLS INTO SWM FACILITY #i.
YH L isqSCOTT R. COLLINStZ
lu No. 35791
k9
z
C;6
V)
LU
CL
U
I 0
z
_0 Of
W Ld
_L2
U)LUII
U)
0
z
Cf)
,
0
Emomom
EL
5
to
III
LU
L9
U
z
UJ
LLJ
3
< z
0
Q) :3
0
ce
w �C_
F_
UJ
-0. 3i
0 0)
0 C�)
Ul
<
ce-
C .0
0 -
UJ
0
F—
L'i 0
�z
UJ
V)
0
0
LU
>,
>
C)
0
U-1
>0
UJ
'55 ()
0
X
Q)
uJ rn
0
U.11
LU
E
cl�
En
JOB NO.
102036
0 >
Cn 0)
SCALE
(n 0
0 Co
1 it =100,
SHEET NO.
2
U)
r _ ✓
('
,
/' t
'i , f1- Jr,,. i
'' /
a ... __.., `--____`-�___- :r'-'„ .. -_- • •'� _ r Y �, r j \e .,. j r t_= a-
��'' / _ /
6 1,
,.
i '. t _._... . __./ i 1 %f , --- a--'..^- _ _-__`.....' - _ � " // ,rd t r � l' t, yf ;' � 1
�,
ry
:J
�,,
, --
_- I--
- _, __ i _- __... 1 ✓ ,t
,
__._ - -
( , '', t ,- _.__- - `, jj i6.r' `„ t i ..__ _._..._._ ._._<.. / „i,- �, , ,% ,r t ,f -�
t 1, `_-...._.,_ 1 i ,` / ` \ ,_ /��
r, -.-- r
I _
E -, _
_ _ r ✓ 1
w. r ! k; �hF t p.
I \ ...` ; i , ,a. '`-', .. u. .v_._ __-'�`.--'--- .--__ -- /'- ,J'f r"'f tjJ �(+/ (.. i
�_ i / ..
3 t , _ __--- i € 3 • i, ! \ � ` ✓ '-'` ,r'� t �� 7f \ 1-a' sr,.-
., , },
'4
'� ' ,^ - ..-
..n .- .-.. �.�^ r
M
�s
k `� - ,.
t s _ ) .._..._... ...,.., , t - _. -
. ; l _ ., .� - �^�,. • ,-- � ,,,'- _- ' ''''`` ''i' ,1-j �
.-- r ,
- - /:
r -' , F
I
i' - ,r`
/ /
_ i r G° 'f r ARfEAMWIT IN (zEENWAYE,•EN1 NTSHALO ?:„
F e r ` DAM & OWN'SLOPE Ee 16ANENT SHALL
- r
, _
11 "._ f RfMAINUNDIS ��-6URINC (� J
izoPE
RT t' rj
' 1 ) C 1 , I f ---`- /' r"" =' e _--... _.. \s _ CO . STRUC TON. Pf FJP SWM FAC`4LITY ,._.. , ,+r {'.
r `+ r1-; -- LINE.(.TYP.) ! T , ty r,
l z 4, - __
(;I, j t / t_ - - 1, - - SHA1 L`.BE B af2ADEp;1(vTE NALLY TO HAVE A }
___
Ii ( 1 . , _... __,.l f _ �- �, \ , \. SEDIMENT OREBAY A ` A UATIC BENCH &'i f { ';
% a
y _._.
Y ,; j : _.: - .._.. \ MINf UM Fria SID..SLO 5 AS SHOWN '.
` t , ", V I d' i r i t `< r --` - ,''' ._....r �.. f _ ( :t 1
_ /
t
t
, \
e
l -
._ , _
o _
a : ,:i _. _ .__ _ .__.. _,�.,
t �€ I 1
, r
_<
r _ .._,_.,_.
n ( _
\ ' I f # ..... --..�\.
;" � __. .. ." "�__... � • :., f , i :... ,, k.<,.,... '\ _._ -"' \ \i 1 ' `l \ ' � i'; t tJ,'•/?i +i
.., ` l ; s 1 I -=" \ - .-. _ _. __. _._ `ems ,
Y-:„
4�
i
r
' 1,:. .;! /��`^
�H.
S i - k �.--^ \ ,,,, .. f 4' 4 1 ✓' ``' \- , `\ !�'�'. t't _ 1-3 r
! y
vi. "e
t
i'-. .. --'.,
u-`: ._ _,.-_ o �O. "' t r l,I _ � ,.� ...,. �- i.''� .�........_ ,- i 0 � � ' , ;-1,J 1 '^. 1 �. t - ,, r ., �t
T
(„ _ r, ,f
_..
-- -
_,. '' I _
•
,
^'� _
( 11
e r t
s <„--...._ I „ .p .--... ..._ ._ __._..-_. `\ 1 S ''{!'1 ,1-^t, f Sr:
..-..._.- ., F"0 , , a. .,.� ..
__
i _ , ,..
, .r __
f
. - 3 x`.. . , rya -. _.,-,^_ / `
... ._. .:•..-___ \ 1 1- "1 : +, , . ./`` .. ._ r = ,...-� - _ - �- \ \t �' 1 ' ' r} r,,., . r`� F .>
---
, , \ I , I \ f , } i . . , _ _ _ -_.. f r"r t ` g t i
f
,.__,.,_
t
> ! i .- -
,N...,, ., ,%j Y.'
-"_ „ I
-. -_ 1 t ft
\ ,
, , i
.. < \ \ \ \ ,l , J :( ; :;, ,; ,.. '-'--_ -,. " 1 a , L j ",,�, ,r11f ,a y't is t"; - i �' t
f(
j .^ p / , j \ ` I p,... - e '"_---_ _ 1 ' �``'-''"''. t ;!, ;1I t ,.y,... .qb:
-_
e , , ' �. _ ar ar -,
m \ y ,, -
__
�'� -
_ -' /
1
, r T ; I _._ r'7 r' r r { rr r, ) > ,J
, ,
,. c �, !. %
/f/ i
, . ,` K , --1,_, i € r: �:• _.__-... .,.., t "✓ % ! r f i k'+ 1 7 �;T,~,
l.._ �.. < t r'-, .� i - % 1 €:. . t - _r' - ' - r r .``\'"`L 4.' ! > i J i� -,, t e - t r : . 7,
,,/' - ,..._.. .\ „ , i " ': _. -__.- ''.;� .. t* ',r ✓{ f 1 ,
>
N<
, t Jf/
1 i r , =`. i ' t 1 , - -'�\ 7" t \:, . l ' e1 -\ \ ,,` ,,,,'' / J I I 1 Jt r -3 ^ '
} i , r : y . ,u. a r ___ ; _. ... :eu '„� f /'r j i' 1. J -,,,
8
d`
\ yy
j.
,' G
: r
�t
r )
fr
,
r-.
� J' J ,
u
J c,
i , `- % \\ \
` --- r'1- - c� t
( f
1
___--
, ;� t
r
_ , r
_. _ .._,,.____ ' j`1 r. 1 , _ -. \ S r.-- ^ Vis. .i
i 7 f �r & PROPOSED TYPE III a i,
_.
i 1
ap \, / �'
a
y`'
r, ,, RETENTOhBASIN i
5: , , ,.._,. r.
i
(�
l I .. ):
,
,
_.-; - ......z i i ..;, f - t @ -,.....r,, r( ' ,11, 5 r ''vf,a:.:::' a,:,# •:vl'. ,.,._ t -,,, �,,
_ r a :, s ! • : ,1 r �� SWM FACILITY -#1- a i
_.. - , i
_...._ \ t
- \ ....-.
i t t x ,.1
is , , _.. \ i t�
D # 1. \ 1,
f t. - \'•,
,s , t : 3 i� i ',�it" ��'` r. 'r l y\\\j\\ 1 1 t .Y, qq '-k. 1ti
y'
} , :,.<:
\' ; s
' 1
ATER UALITY 8c DETENJ7'lON I• i �� s :� ''``u
t I, �\ I
g i
- , i t ` , ,i p' , �.€31 , � . ,may,. �pF '' bl �
1
,
_ s. OOsf t3.
__.. � 1 ... , :. � GRE T FOR 595 0 OF , -.. , ,\ e ; � i . ` `^,�
; ____- __ .•. ' -,: ; s , .. , , . , , r t , --, , ,, �. f '., b k � . , , ..,, _ :: �' � gat. fd 1-'r '\
__ i t - +# rr
/' i
1
_.
, ,
, I
,
n FUZtJR fA�RRi/lOrJS ARL�A) APPROXIMATE'LOCATI NOF: ,, ?' ;f, �r
i t;r
1 ,! , 1 r ' \
h !j
t
1
ING D
,
,
AWAY BY ERS /' «:.., ; ;
f, _ $ EXIST R� C}TM a H $,.,.,,, „ , _ (:. I_ ,. "\ ;`, "'\
..` ... r1- ,.t l; ;{ j; f /` I $.o ,. 1 , S IJ ,t c',.:'S ......... - - _ -
1 •t ) )) )t� .t'.
__.-..-.. , "f ,.,.....-. '`;'y `:'; (, ' r l t i I tti ,`e t, , , i 1 f 1 1j
...__,._, ti ;} v. t , € 1 .'�' ( -._tj, i ttt , ;aj;
i
jJp)
2 .21 c3xx
- ;i ., ,[ , rntn.
:,,:
r ,� !
%'
i
I`,
1€
ff
t
TC -- -
'1
t
1
3,
t i" �!. ' t i ,tai-. ..�
t 1
S
!! t
i ,i
;u t
�t a ,l
L I-
i
i
1 S ';._
l `
i
_ - „° r
,
TM o zoo-oo-oo-0 600 -:.
T
,.: ` , " a d :r, 1 , .1. : (, , ) I ,�._,._ .--.,. I IS 3 5 , '. \ F::: µ R4 t _ l -'% , i
,
.I 1 .. ;':F .....r '1 7
¢ ._, j : :., ya�...u. •.> .�- < ,9 t r _�Naf .r,.-�--_:':
I
ii , '9
{ _.j_ 7
i
f �::_ F
L
t� � 4
,�J
i � a 7 as-
�sf
r h
r -
_
I -
.. _,_ k v,xs.
--- -- - ...... ... wF a a,
- ry
.... / ..,_t ._. .. / ,
,_ _ t , ..... C- .., -
t t
c_.. Fn ., :- __..-- ,.+ F t a p" ` 5 ' ,.-,..-..a I _ i .,""` rA<„'yj2:. t _, r-"_'--'-'_`_' -
__
' i TOIINCENTER DRIVE v - ""
" -_
N
\
.._.-�<_--._ V
s ,. ...._ P' zo 00 0 6 -
_. _«_ __ , .,-. RTI NS OF TM o
__. INAGE R�ROIw O C5 0
.r.
3
a -P- ?' ,. .... .. 6
\. . :.:,-:. _; s; ., `; -,� __ SHAL OUTFALL INTO THE PROPOSED SWM FA ILITY #z
` � 1
€ /' 4 f,r _.. r ,: FOR PPLEME TAL VNATER QU+LITYTRE TMEN C PRlO
i J -J'
1- I i t m r, t,� a n ' 1 j �
4 ¢EIiG P D INTO T.HE E�f1STING PIPE INTOW
:I ' 8 '7: `, =' \ Vii' 1 i � y ,,' -
I Y ,„7 _._-_-__ _.-_.-._.\. ._ ,._.x....# §{;' I' r' EOTEPI�RI IPW EREITS,DRjINAG II,LTHENRECEIVE
qi 19 / r D AE7DITIONAL WATER QUALITY '' 1-,f
DET TIO AN �!
1� -" , `;. , t i 1 i , - --, r �,_,__-,,. '-, ' I t` f §EATivIEN1T`FROM THE PROPOSED SWWrF CI,LITY #� J,! 1
i
3 r
,. __. ..,_-.-'...._._ .._... ., � F ;,; �....._^.-, ..-,.,Y-,.:, - '.. 4% �a _.... 1 � f' i` -,.J"J � rr r'� 7� J
' r
L - '
`.
' 't
Z
_._ _. : .
I , _...
__: ..
f
t
ii >�
c, . ,
4
--, ( i
f ' ! D _.
O$E
I R
OP DENHANCE
,
w
I ). I j
: r
_ , -
,, i i 11 i i i i i EXTENDED C}ETEf�TION i \ 1 `""
!. ,
t
_._-_ v r, 3.. :-'€ ,.;,,....__ J 1' / ACILITY SWMFACILITY#z
1}
j : (/'
f 1
t
1 , , t : , ..... 1 tt
"t i i 1 - i\ f1 f
1 i F , t� 4 f ..
_ _, !' - \ P o zoo oo-oo-0 6o \
, I �M 5 1 - \ ,
., d j -._
\\\
i f ,t f Il t i /:' I i i, 1 ,... 1-r....._-o� i. _ .,-I , '\ _d^..,r,.. . -
;, ,, . , , �.{
,
,
� _
_ - - / 1 l,/ `' !
1
f
j i r`✓
/`
/j ry J t r(,' � ,
r
/'
Jt.
f
r
f>
s
_. _ � r
/f ' _
- f;''',, r' ,, „ I
r
r rt
f 7 w r��/.'f � � ,f ,3 /J � I
r°
! ///� /
i' kk
/'x r ?
'1- `"e.:-,._ i''✓ ' : f .1 1 1
V,
t't P ,
r
@ f j '.
4 y t / ,. jj/r f' r '
-,_ / /JJf 1
J
r /!
`\ /
fJfr ! FI f1f /f�,% 'i /' ,'1:
f � f t r,<
r
'fir r r rf'f` ( r 1-J
�r r
i
� / f t� Jr, t l� I
f 1 / E
1-J / if f` r f
i \
.I,
i',
:S
\
f
f f j, II/ 'f fJft,
if lr
I :t t `f / f,/ /f --- - � PS J
: ,
' }
7 - }
s
f Ila
, J
J i
t 1-r'
j I 17f r _
1'lrr'
/ ` ', -
:,:;
, j t . r , ___.._,
I t, ti ( ,
f \`-..
/ J i
f.
V'
f
/C
tiff I - �`-^"f�rr`.,
s^,"
I =
f` r
rr ,
i r
E_� /r
r `- i t
/ I
_ J
l l
L 1....,,_..,. • f
r--`_ _ 1
i
-(`f�ff�(�JfJ,f 1 t q
~moi f+
1
\ ((tt
�(
f w 33
i
1 't
_J
,� i
t
- .,. ;
a �,
i �
r } �� s / -7 ({j ` 1
I I ��J `',
v .. G / f ''--�...,J E i ,jf , "r fir- y
�••' � ' r
i
_
i I f 1 e, ``
�I
f
!; � ' l- j
i !i+
fr
f' f
v., r 1 % ! -
L
- G
__. , --__. -- --.,. _.____�-.-,-_- _-,--_
�_- -- j
,,`
Basin Input Data
BasinFlow printout
INPUT:
Basin: Hollymead Town Center Retention Basin
Type III
\� g Contour Areas
4J Elevation(ft) Area(sf) Computed Vol.(cy)
}� 512.00 io564,00 0.0
J 514.00 1336g.00 884.4
! ;' ' 51-6.00 26628.00 1-993.2
518.00 20037,00 3349'2
529.00 25095.00 41-83.2
t 520.00 26424.00 5137.2
ULiV� 522.00 29191.00 71-96.1-
524-00 3zo61-.00 9463.9
525'00 33505.00 1-o678,o
Start_Elevation(ft) 51-9,00 VOL(cy) 4283'20
200 F-7 ` I r- ,`--j ;iii -� j 400
IM FEET )
Outlet Structures
Inflow Hydrographs
Routing Method:
Area 2 -Year Outfall 10 -Year Outfall
Description (acres)
storage -indication
4OutletStructures
3InflowHydrographs
D.A. #1A 13.00
Outlet structure o
2- Year, SCS 24-hour Storm Distribution
Culvert
Area (acres) 22.220
2_ Year, SCS 24-hour Storm Distribution
name:Barrel
CN 88.000
inflow (cfs) 6o.748 at 1-1-.96 (hrs)
multiple 1-
Type z
dischar e cfs 1-z. at 1-z.z (hrs)
discharge out of riser
rainfall, P (in) 3.700
water level (ft)) 521-703 at 12.24 (hrs)
D (in) 36.000
time of cont. (hrs) o.2800
storage (cy) 6877-857
h (in) 0.000
Length (ft) 86.000
time increment (hrs) 0.0200
time limit(hrs) 60.000
1 -o -Year, SCS z4 -hour Storm Distribution
Slope 0.070
fudgefactor 1-.00
inflow (cfs) 205.094 at 1-1-.96 (hrs)
Mannings n 0.013
routed true
discharge (cfs) 43.32o at 1-2.14 (hrs)
Inlet coeff. Ke 0.500
peak flow (cfs) 6o.748
water level 523.165 1-2.1-4 (hrs)
Equation constant set 3
peal<time (hrs) 1-1-.970
ra
storage (cy) 8490.806
9
Invert(ft) 51-6.000
volume(cy) 731-4-1-1-6
loo -Year, SCS z4 -hour Storm Distribution
Outlet structure 1-
1-o- Year, SCS 24-hour Storm Distribution
inflow (cfs) 189.45o at 1-1-.96 (hrs)
Curve
Area (acres) zz.220
discharge (cfs) 171-.979 at 1-2.02 (hrs)
name:Anti-Vortex Device
CN 88.000
water level (ft) 523.962 at 12.02 (hrs)
multiple 1-
Type z
storage (cy) 941-8.448
Invert (ft) 52z.zo0
rainfall, P (in) 5.600
discharge into riser
time of cont. (hrs) o.2800
file: fortyeightAxt
time increment (hrs) 0.0200
timelimit(hrs) 6o.000
Outlet structure 2
fudge factor 1.00
Orifice
routed true
name:Low-FlowOrifices
peakflow(cfs) 205,095
area (sf) 0.442
peaktime (hrs) 1-1-.970
diameter ordepth(in) 9.000
volume(cy) 1-2653.402
width for rect. (in) 0.000
coefficient o.600
1-oo- Year, SCS 24-hour Storm
invert (ft) 519-000
Distribution
multiple 4
Area (acres) 22.220
discharge into riser
CN 88.000
Type 2
Outlet structure 3
rainfall, P (in) 9.1-00
Weir
time of cone (hrs) o.1-800
name: Emergency Spillway
time increment (hrs) 0.oz00
length (ft) 45,000
time limit (hrs) 6o.000
side angle 0.000
fudgefactor 1-.00
coefficient 3.300
routed true
invert(ft) 523<20o
peaI-flow(cfs) ?89,451-
multiple 1
peak time (hrs) 11.970
discharge through dam
volume (cy) 22809'851
Watershed Summary
\}
1`I t
+r
t'
1 r� t :;
11 , ,
-i
1-y x
1, f.1- } X' 7 ) 1 ';
fl;( i tfY� est
i _ ii
i� (
_ ,-
-r
/.
1`:
t
.--,-.-•-- t
i"
/ _
T
,.
i
ED r
ROP S TYPE II "dU i
"int . 1 7- �.
;
f
,� r
TE O BA�'1N
-r� '.:i i'
RE TI N
�r : r
. f '., 1'1- '_F• ! I
r I J t` , t} (SWM ACILITY #'�) ,
��
� . //
f('r
1 ti
i' i
i
€ f,
,- � I:. , t 1r �i t,
i f J t 1 17 ` t 1 'r;t I
pt 3' ,a 1 , t i , I\ ,
1 � Y
i \
/ 7' (J
r S , �, el ',F 4 tp i -
\\
�,..
,` 3
i
e f 1 fl
F' V l E.F , 1 11 i v
` pr 9 , t a , ''.t i
, , 1
w
R
i
'. z.
t
t,
' y i
i
r y \
{' t i >v`' . t t \ t t __1 `
t xh.:, 'i k' fit,, "-.,
3 _ _ 1 \
t
i
t rt : 1. ,� - I
1^ 1.: t ^^^"www
i
r t.
' h 4 )1-4 kA \ \ } t fs l.'\
:t
,
\, t
-......i t , - ,
\ i \\\ i
,- tt ,i �.. y r Y,.l 1
1 jjj ` a t �\ ' \' ' / r 1 i
tk > ' * i
I }i �t J �t t t4\ \ \•>~..._-.« r`1-! 1 i t 3 / • \:
i �, a i 1�� ,,`1 t
\ I ,jY ,T' y ', 7 . r-1- �, § .. i<\
f \ , r /� r {
i' C' l ,j1- A,� 4 n,', phi('i'^rl ,
1
} t n - rt tt_t :1�Ti �. e y "'. i t ', r -! f l -
1 ,l t r t
I) r r Ili \; f ; t:' j �t, t i t �`
\\\
` ` t
1 f r '�t .r _,_-_----- �',� I t : -',r � i I t { jl ,-
t JJJ
•! r S
.i i f , rf /'
1-1 1 1 ,p i ', tc ,} ; Jr t� '-i r
Y,. i t ,`�.i 1-}}1 1 .�r1�rJ / ! '.
J `IA i I Al ; 1- j ' t l
` I i�'I E t 1\ ,�{Y ',t t ,J r-
/ t
��y,� '
Pre -Development Post -Development
Area
2 -Year Outfall
10 -Year Outfall
Area 2 -Year Outfall 10 -Year Outfall
Description (acres)
CN (cfs)
(cffs)
(acres) CIN (cfs) (cfs)
D.A. #1A 13.00
58.0 5.70
19..98
22.21 88.0 12.98 43.32
D.A. #113 9.21
66.9 9.66
24..00
Total= 22.21 15.36 43..97 22.21 12.98 43.32
.f
=S
d
F . fpJ�p}�
✓ M
1
'f
l
9t
f
y,Irp 5l�1 f I
�G`TH olp/
�_
SCOTT R, COLLINSZ
No. 35791 ,�
PO ��
l ,�
.1ft I NAL E���
END LL
_REPAIR & REPLACE AS
i NECESSARY\, THE RIPRAP -;
;j OUTFALL. VDQT STD: EC -1, _
} __d'L.-HI, TYPE, B RIPRAP
- /IL-6 ,Wr-12°,W,-10',D-,2 _min:) �s
V4
--i-. '."'- _`'... D;s ,1 t' F ':f;e' / -•:ar1
.'S ad'.
2
I
I f
1 I•
1 ?'
O i k
i
h
' ..,,:.:%...+• .. ... .. ._..-.... i ', mit -
1 r
i
�f
i
r
--E
EXISTING
.... .> ........- t _...- ..
j i
i t .:M�y.. , ...� - - f. / � E ENDif'ALL
-, EPI_&. -REP -LADE
....._ XCESSARY THE RIPRAP - - -. 1 _. - r ` " - _.., w• :__
OUTFALL, VDOT.-,STD."
CL, 1,_TYPE $""RTP RAP s _m I
AQUATIC BENCH LANDSCAPING
J
_
- ut <.
Caliper
Size
10 -Year
TotalCanopy
AS NOTED ° 3
FQREBAYSPILLWAY EMERCENCYSPILLWAY
I rile[ Argo,
°-
Quantity Canopy
Aquatic Bench Landscaping
CA
Clethra alnifolia
Hummingbird BUmmersweet
�� r
Standard Dimension
_. Pte.
Approx-
2'
18
25
400
BDN
Viburnum Dentatum
Arrowwood Viburnum
27 33 112 60 � 2 37 12 22P, '` `'h A-^�r• I . �- ,-- ,'.'� .,,• F�
31-4'
31
30
,
HVI
Hamamelis Vir iniana
Common 'Witchhazel
48 58 9 84 10C 62 4,2 �rrtrnsl v� �� 03.,E Vm
0'
113
28
3104
AP/FR
Beed mix: 50% Agrostis
Autumn Bentcdrass & Red
sea per
7 04112 1 140 �:' ' (8-97 Ar i-"Vor sir Cara OL), s,
84 100 126 147. 104 1 a,?G€ nYa � CapI LI
✓ CULVERT:
Fescue
manlacturers
1
1,150 sf
r
Festuca rubra
recommendations
ar
,,I.3 An1l V-_: ax day ?jE,:,� (r ap arat: > iserl hr9ianvf AiarYd tat
➢
3 y
�r J � f
kr
�� M
;t Ir dat atim ,AE 1a be#aear 613,,Jne Li7., and riser Ofi.) i; grmi3ler
than oiata' area, (Area orr icer I.C.)
4 Slab r €nforcernertt to be A T M AP I F
--— FIGURE 3.01 - la
Hoiii(�,eiteoir.s Etiibrtr'z%srierats oto/ S'eepuge Controls
Homogeneous fill
1
4' min
C `-Cut cuff trench -4 below suitable I
I material
Soil or rack L - -- - _ ._...- ._._..-..-. _ - J
TYPICAL HOMOGENEOUS
EMBANKMENT
Transition fill
,,,..mock or gravel
e' "" -' Carse filt r
Perforated collector around slo-s �Blonket strain
Eoundati€ln drain
FOUNDATION DRAIN BLANKET DRAIN
Chimney drain
Sand, gravel or rock
drain outlet
- Bock or gravel
Rock toe �j drain
,-Transition filter Transition fitter
CHIMNEY DRAIN TOE DRAIN
:Sozlree: SCS F,n illeet-Mg t ielct 1Arawful
3,01 - 3
r " .
Abb.
Scientific Name
Conymn Dame
Caliper
Size
10 -Year
TotalCanopy
AS NOTED ° 3
FQREBAYSPILLWAY EMERCENCYSPILLWAY
I rile[ Argo,
°-
Quantity Canopy
Aquatic Bench Landscaping
CA
Clethra alnifolia
Hummingbird BUmmersweet
�� r
Standard Dimension
_. Pte.
Approx-
2'
18
25
400
BDN
Viburnum Dentatum
Arrowwood Viburnum
27 33 112 60 � 2 37 12 22P, '` `'h A-^�r• I . �- ,-- ,'.'� .,,• F�
31-4'
31
30
930
HVI
Hamamelis Vir iniana
Common 'Witchhazel
48 58 9 84 10C 62 4,2 �rrtrnsl v� �� 03.,E Vm
0'
113
28
3104
AP/FR
Beed mix: 50% Agrostis
Autumn Bentcdrass & Red
sea per
7 04112 1 140 �:' ' (8-97 Ar i-"Vor sir Cara OL), s,
84 100 126 147. 104 1 a,?G€ nYa � CapI LI
Perennans, 50%
Fescue
manlacturers
1
1,150 sf
r
Festuca rubra
recommendations
,,I.3 An1l V-_: ax day ?jE,:,� (r ap arat: > iserl hr9ianvf AiarYd tat
r RETENTION BASIN TYPE III AQUATIC BENCH PLANTINGS.
SEED
MIX FOR AUTUMN BENTGRASS & RED FESCUE
Technical Bulletin 7 Minimum Standard 3.02
s
1/2" zinc p2a-E;ad ho ixk
mit.chmd rith 3{0' te,atme�r
* ot --r 2--1/b- din, hole z
ti
IsometricC N
„1{.i= Hhpg! date
pipe . t�iks� i.* EW -1
HVFX #tr;Ac vyQ plo.xkty witkt
1 0 4-1/8' heilps And 1/4 ptsta
r r11on,2rt6t,Tad 1�y PIANtiU
aSalutlow Ina- or equal
r 0
1 0000
_ - - - • dhawfl 'rrith agtiana plate
Ik
T{ 01,110
MOTatd, (khickj HDPE etavetucal grlaLaup WAh
2-1/3' holey ruid 1/4-' late
section
idaaturad by iastitc
Sioluuonv Tn374 PT equal
d" din, h.nia
0
\-VDOs eta. M-1
i t
I sp`''y,
--- ----------------
Elevation -------
.�Jtl� Eleva.tion
r,riilae
PLASTIC IteGL�e
,
SOLUTIONS
BMP DEBRIS VA ice
L7LB�:'I C�'ACx INC
xRir. plastic -a drelirJrJ.arm
TB7-3
I for mwater Iain a ern nt
W' T pt
FOREBAY WEIR CREST w/ CREST ELEV.= 523.20'
SCALE o
ELEV.=516'
AS NOTED ° 3
FQREBAYSPILLWAY EMERCENCYSPILLWAY
I rile[ Argo,
°-
SHEET No.
NTS NTS
€ 1Juf`,lArrNN
7
(a�
�� r
Standard Dimension
_. Pte.
Approx-
t C
# oil. % ,+ai. �5 i ,t 1 r �.
E.
24 'fit? 48 o% :a4 A9
�Y
27 33 112 60 � 2 37 12 22P, '` `'h A-^�r• I . �- ,-- ,'.'� .,,• F�
,
10 60 72 41 2,26
r,k6 44 60 72 48 2.7
48 58 9 84 10C 62 4,2 �rrtrnsl v� �� 03.,E Vm
Sld
5- 6,F 1!2 1 84 100 1 rj, den f J #
'-!`,f iJ' I �°�,t i
. iniJii''.�ftai'
640 7 z 96 414 1 ,rf i 6A8 �Wn yr�W
d
fm ',,', 913 1:'4 1 84 12 5.39
72 86 108 128 4x,) 1 6,83
7 04112 1 140 �:' ' (8-97 Ar i-"Vor sir Cara OL), s,
84 100 126 147. 104 1 a,?G€ nYa � CapI LI
{sf�rt
N)Det
1
r
_Ainli-Vc.fi3 5 r t7 C . is
,,I.3 An1l V-_: ax day ?jE,:,� (r ap arat: > iserl hr9ianvf AiarYd tat
.-r, ,1ar.q with A+ TPA w.uI Rection ,�i-A.
11) 'F_',irnpen'4on-ubjacti lio 1'i' nis i:,hle %,ori Hoflu'; f ASTts - {•.'41.8.
;t Ir dat atim ,AE 1a be#aear 613,,Jne Li7., and riser Ofi.) i; grmi3ler
than oiata' area, (Area orr icer I.C.)
4 Slab r €nforcernertt to be A T M AP I F
' 1L J r{:?"G"�'jYt7E 9 f!I"`fi`9 i.Ebril9f-:<f71 t `` bo A,af 1 @, rj 1 60 E
x i S";2,5 x kjY2,5iNN7 rri ilirrnu'n
r�ir- prJ rti�: i i + t 1 f ! 1,tS i} s i, Cnrg€:rstF
a
- •. All C}3 ,Ersr4wty51.S sFlr!f t tf 51ioCe.'i$i1[;.
s.) 01-1 Frame & 03fale is a. „iilac e fc)i -1 i' 117p, riiiers ant- .larowe,
Precast Anfi-Vor ex Device (Cap and Riser) VA '"Hanson
VDOT STD. EC -1, --
CL. II, TYPE B
RIP -RAP
General Construction notes for Stormwater Manaaement Plans
1. All dams and constructed fill to be within 95% of
maximum dry density and 2% of optimum
moisture content. All fill material to be approved by a
geotechnical engineer. A
geotechnical engineer is to be present during construction of
dams.
2. Pipe and riser joints are to be watertight within
stormwater management facilities.
3. For temporary sediment traps or basins which are to be
converted to permanent stormwater
management facilities; conversion is not to take place until
the site is stabilized, and
permission has been obtained from the County erosion control
inspector.
UTILIZE EXISTING TOP OF DAM &
GRADED ACCESS AT ELEV =526 f. NOTE.•
HIGHEST ANALYZED BASIN ELEV,=525' &
WD TH AT ELEV 525' EXCEEDS 10'
CUT IN 45' GRASS LINED
HANSON CONCRETE EMERGENCY SPILLWAY WEIR
ANTI—VORTEX TRASH 'lam/ CREST ELEV.= 523.20'
RACK
zh
10' AQUATIC \ o
BENCH \ �.
ASH RACKS SHALL BE INSTALLED ON
ALL ORIFICES PER VSMH TECHNICAL
BULLETIN #7, OR EQUIVALENT
ORIFICE COEFF.= 0.6
PLUG EXISTING DEWATERING
ORIFICE, RAISE EXISTING 048"
RCP RISER TO ELEV.=522.20' &
INSTALL FOUR -09" ORIFICES
ELEV -519 O'
r�H 0��
IS
SCOTT R. COLLINSZ
a-,
No. 35791 �
jONAL �'
Cn
EXIS77NG 36" RCP BARREL
CONTRACTOR SHALL ENSURE RISER 86 LF @ 7% (Y')
IS EMBEDDED 6" WITHIN A MIN. 18" INV. IN= 516.0'
THICK 08' CONCRETE BASE INV. OUT= 510.0' CSI 7
PRINCIPAL SPILLWAY NMERM 45
(NO T TO ,SCALE'
t CL
0!
0
VZ
til r--1 a
U �z
100 YEAR 10 YEAR EXISTING TOP OF DAM & o WWUTILIZE
W.S.E.=523.96 W.S.E.=523.17
WQV PROVIDED= GRADED ACCESS AT ELEV.=526 f. NOTE.
112 947cf 2 YEAR HIGHEST ANALYZED BASIN ELEV =525' & w o _J
W.SE.=521.70 WIDTH AT ELEV. 525' EXCEEDS 10' N
HANSO CUT IN 45' GRASS LINEDZ o
3' WIDE FOREBA:Y TOP OF CONCRETE EMERGENCY SPILLWAY WEIR �--i
DAM ELEV.= 5183' w/ 10' ANT7-VORTEX w/ CREST ELEV.= 523.20' o
WIDE RIPRAP LINED TRASH RA CK
FOREBAY WEIM CREST W J 0
ELEV. = 51t 6'
�., MAX. EMBANKMENTL9
LU
HT.=14' (526-512)
----------
_ _ __ C o
7'}—
L
MWSE=519'PONDING \� 10 AQUATICZ x
BENCH �
V-3 DEP TH Com, UJ
ORIFICE COEFF. = 0.6
BOTTOM OF FOREBA Y -J
ELEV = 512.0'
BOTTOM OF RETEN7701V
BASIN= 512.0'
UTILIZE EXISTING TOP OF DAM &
GRADED ACCESS AT ELEV =526'-±. NO TE:
HIGHEST ANALYZED BASIN ELEV =525' &
WIDTH AT ELEV 525' EXCEEDS 10'
3' WIDE
FOREBAY TOP OF
DAM ELEV.= 518'
------- ------------- - ----- ----
-- _ _ -- --
9'
2>
10'
- u�
4\i _ LD °
i < 3
PLUG E CONTRACTOR SHALL ENSURE < T
EXISTING DEWATERING °
EMBANKMENT CONTAINS AN EXISTING
ORIFICE, RAISE EXISTING 048" IMPERVIOUS CORE w/ CUTOFF TRENCH
RCP RISER TO ELEV.=522.20 & EXISTING 36" RCP BARREL IN ACCORDANCE w/ THE DETAIL w 0� � -°
INSTALL FOUR -09" ORIFICES ® Lia ° U
86 LF @ 77. SHOWN ON THIS SHEET.
ELEV. =519.0' 0_- In Z P
INV. 1N= 516.0 �' z U)
INV OUT= 510.0' y� <
W O
0
°
TYPE III .RETENTION BASIN LLJ
(NOT TO SCALE) 0 z
J�
UTILIZE EXISTING TOP OF DAM & 0
°
100 YEAR 2 & 70—YEAR STORM GRADED ACCESS AT ELEV=526'1. NOTE. o
W.S.IE.=52396 EVENTS DO NOT CREST THE HIGHEST ANALYZED BASIN ELEV. =525' &
.-140 YEAR EMERGENCY SPILLWAY WIDTH AT ELEV. 525' EXCEEDS 10' w/ °
WI. S. E. =523.17 ADEQUATE FREEBOARD "'
> o
2 YEAR °
W.S.E. = 521.70 °
100 YEAR X
W.S.E.=523.96
1.04' OF FREEBOARD L E
DURING THE 100- YR
p STORM EVENT RELATIVE o 0
TO 525' DESIGN ELEV
'a � r c�• C� � � E n
0
Lu
U)
0
45 '- WEIR COEFF. = 3.3
WEIR COEFF.= 3.3 Jor3 No. 102036CUT IN 45' GRASS LINED
U ° ll
j
O N
10' WIDE RIPRAP LINED —J EMERGENCY SPILLWAY WEIRm
o
FOREBAY WEIR CREST w/ CREST ELEV.= 523.20'
SCALE o
ELEV.=516'
AS NOTED ° 3
FQREBAYSPILLWAY EMERCENCYSPILLWAY
°-
SHEET No.
NTS NTS
7
(a�
t C
f �
� l
✓ / x
._'.
i
_TO PROVIDE DETENTION &
ROPOS--E"TDRESAW%FACILITY
#1
ADDITIONAL QUALITY
TMENT
-� ak
i�
EXISTING 048"�' _
M \
xi
st
,mom-' STORM SEWER z
_n
C
F1GT .07 - 2
. 'aOn - Section
f- _o wii�i
i
T
,�esJQ lent F Ia
t~
mi1d-,Slala Rae
Y IG�Ui RE, 3,07 - 3c
y
D'E'LI }"A NPE ti5.*..,YR
/pY f
P
CANOPY (sf)
r
/
QUANTITY
COVERAGE(,f}
tF 'Y PLATE
9
17
R {
CF
CALYCANTHUS FLORIDUS
M L.1-; lAeE RISER
f
32
832
IV
1 1
PAVEETSPIRE
64
20
�! y
it
3: 1 SIDE SL OPES
up
t
L
.,
\
Pod
PROPOSED 36" CONC. RISER
Dip P*'We
E
;.
MINL {
{ i
. 1
,
ff
?
Z
LU06"
i
r ' F 41 C A
f PV 4
/ t 20 IY Q'
17 CO
F t jF
l
f �'
SWM IACIL rI Y #2 DETAIL
IT A TIL T7 C+/ �' A TITATl"' T)T A AT'!
/
y
COMMON NAME
/pY f
P
CANOPY (sf)
r
/
QUANTITY
COVERAGE(,f}
BU)TTONBUSH
9
17
R {
CF
CALYCANTHUS FLORIDUS
SVIVEETSHRUB (FRAGRANT)
f
32
832
IV
1 1
PAVEETSPIRE
64
20
1,280
3: 1 SIDE SL OPES
,
t
L
4 T.w s
\
Pod
PROPOSED 36" CONC. RISER
Dip P*'We
E
;.
RIM ELEVATION=527'
{ i
. 1
,
ff
?
Z
LU06"
KI Stindwo
INVERTED PIPE w/ SCREW CAP AT
L 0
o
Q U
O �
PLANT SCHEDULE
SYM
BOTANICAL
COMMON NAME
SIZE
CANOPY (sf)
TOTAL SITE
QUANTITY
COVERAGE(,f}
SHRUBS
CL.A
CLETHRA ALNIFOLIA
SU MMERSWEET CLETHRA 24" HT.
16
41
6S6
CO
CEPHALANTHUS OCCIDENTALIS
BU)TTONBUSH
9
17
153
CF
CALYCANTHUS FLORIDUS
SVIVEETSHRUB (FRAGRANT)
26
32
832
IV
ITEAVIRGINICA
PAVEETSPIRE
64
20
1,280
GRASS
PV I PAN ICU M VIRGATUM SWITCH GRASS
TOTAL CANOPY 2,921
GRASS AREA MIX (GR):
1. GRASS (GR) SHALL BE USED ON THE BOTTOM OF THE ENHANCED EXTENDED DETENTION BASIN.
2. GRASS AREA TO CONSIST OF 50% SHRUBS & 50% GRASSES (BY AREA). GRASS SHALL CONSIST OF PANICUM VIRGATUM SHENANDOAH
& AMSONIA HUBRICHTII AND SHRUBS SHALL CONSIST OF ILEX VERTICILLATA RED SPRITE' AND ILEX GLABRA 'JIM DANDY.
3. CONTRACTOR SHALL USE PLUGS, NOT GALLON OR GREATER SIZED CONTAINERS - SPACED 30" O.C. OR PER SPECIES RECOMMENDATION
p L{ix... 3.07 .- 29�.}y ;ry
Eirka,picelaii
Intie'ta��� ---
<
DAM ELEV = 528'
° •o
.a�drtiortal t± ester O ality N;`olu,me Prcdi� 'd - 2,�,� of
_ r
�
- Mao sttvmo _ �llwae 4.
ANTI -VORTEX IRASHRACK. SEE
A
SHEET 4 FOR ADD17IONAL PROPOSED 20' WIDE GRASS
CDU
ai
f" 2
Wz
'►y
i s
3: 1 SIDE SL OPES
t�w�
I
NA
4 T.w s
\
Pod
PROPOSED 36" CONC. RISER
Dip P*'We
RIM ELEVATION=527'
. 1
0 16
0
?
Z
LU06"
KI Stindwo
INVERTED PIPE w/ SCREW CAP AT
L 0
o
Q U
O �
THE RISER & A 03" ORIFICE OPENING.
0
0
d
� y
s2 �
- a CttlCl�,..r
Poe)
UPSTREAM INVERT INTO RISER=525.0'
'hIieAcd
;o
) Dogti Zen iaf :irxix &LhIx
I lam;" Pxi'l 207 r.
.N
o
a Lo krql 35
I go Mai 457.
X -0
307-4
TH
0
SCOTT R. COLLINSZ
No. 35791 ,�
SIONAL E�
EXIS77NG 10'+ TOP OF
<
DAM ELEV = 528'
° •o
.a�drtiortal t± ester O ality N;`olu,me Prcdi� 'd - 2,�,� of
PROPOSED HANSON CONCRETE
�
ANTI -VORTEX IRASHRACK. SEE
i—d
SHEET 4 FOR ADD17IONAL PROPOSED 20' WIDE GRASS
CDU
INFORMA770N. F — — — WEIR CREST ELEV.=527' w/
Wz
'►y
EC
w c
o
zU
3: 1 SIDE SL OPES
L o
w -o
z
\
z
PROPOSED 36" CONC. RISER
J �
RIM ELEVATION=527'
0 16
0
?
Z
LU06"
INVERTED PIPE w/ SCREW CAP AT
L 0
o
Q U
O �
THE RISER & A 03" ORIFICE OPENING.
0
0
d
DOWNSTREAM INVERT=520' ORIFICE COEFF. = 0.6
s2 �
UPSTREAM INVERT INTO RISER=525.0'
;o
.N
o
0
X -0
TRASH RACKS SHALL BE INSTALLED ON ALL PROPOSED 30" CL. III
ORIFICES IN ACCORDANCE w/ THE DETAILS RCP BARREL
PROFFERS FROM ZMA 1992-14 FOR TMP 03200-00-00-05600
SHOWN ON SHEET 4, OR EQUIVALENT. 109LF @ 1.74%
^ a . INVERT IN=521.90'
INVERT OUT=520.00'
.
0 0
ACCORDANCE WITH THE COMPREHENSIVE PLAN, DURING THAT PERIOD OF TIME, THE PROPERTY SHALL NOT BE AVAILABLE TO ANY OTHER
SUPPORT RISER S77?UCTURE IN ACCORDANCE w/ VESCH
m
3.14. CONTRACTOR SHALL INSTALL A MINIMUM OF 30"
COMPACTED SOIL OR AGGREGATE OVER 6x6 x1/4" THICK
0 7,
DEEMED ACCESSORY AND SUBORDINATE TO THE MOBILE HOME PARK. IN THE EVENT THE CONDITIONS OF SP -93-13 ARE NOT MET, OR AT THE
GALV. STEEL BASE PLATE OR EMBED THE RISER 6"
w
E
INTO AN 18" THICK (MINIMUM) CONCRETE BASE
,C3
PMNCIPLE SPILLWAY
(NOT TO SCALE)
s
— —
IOee Fool 518 522 Low Marsh 522-52
Water o
___ .... P _... �_ .._ ... _.. _)- ..._.._._._ ._(__.-.__. _`�) ., .._...-___ High Marsh (524-525) Extended Detention {5�5 �27j Combined SWM �acili Flanletrics , , ; - �. •: ., �' LU �
Til � tl lit � l° etltoe�l Basin rr � �11�� � Laal rte}' �,..
i Elevation Area Vollume Elevatlorr jArea Volume ! Elevation i Area Volume Elevation Area Volume
Elevation Area Volume Percentage cf'IV ate Gualty Overage 1% � N
� 3 I � � 3 �, a � �. �_
t.
ft. f ft- ft. t f
( ) (ft) (ift ( ) (ft } ft ( ) ft {ft ( ) ft ft ( ) fft ft {s ater OUalth "Volume O I3 e at - 1cl-S of
_..... _ ) ( } .. _ t ... ) ( (i ( ( )
E
i x
e
i 1 3 "� - N
518 109 �1 518
518 0 r. ,.: r-
518 1t 9 �.;�ter 0
-_ - - -
f
uait� �`_ 1LIrT-ie O gra �,e, at 1:� _ ,��_ of U
i
11
I
i t N
LLj
520 439 5 520
� 520 520
520 4:39 511
t
i L
? A
Q
522 959 " 1'875 522 975 521
522
522 1,934 2707ate L
uJ
524 L 2,7583,578 524 2,753 - 524 - - 524 2,753 7,370 E.rrIna �: Eta Cteter7llC l3aStH
525 4,790 3,725 525 4.790 525 4,7 11,095 A& ti rlalWater Otuallhf, Required =
526 -.... _.. _.. ___.. _.._ ...... ... ....._ ....... ._..Additional .tV aterr O Ua l4P rwi did = t
�o �
r 5,647 526 6,549
. _._...
..-..... C
527 7,640 12,734 5277,640 23 829 �/ Q o
528 9,' 43 32,258 ditioria.l Water Gina lite 'Valu me P&qur red= '1, O a � cf � � E In
Surface Area % _ Tar et %- a
Deep Pool 20 20
Love Marsh 37 35
High Marsh 43 45
- 100 ' 1100
ENHANCED EXTENDED DETENTION SUMMARY:
SHALLOW MARSH WATER SURFACE ELEVATION=525'
EXTENDED DETENTION WATER SURFACE ELEVATION=527 (3' MAX. ABOVE SHALLOW MARSH WSE)
DEEP POOL ELEVATIONS: 518'-522'
LOW MARSH ELEVATIONS: 522'-524'
HIGH MARSH ELEVATIONS: 524'•-525'
EXTENDED DETENTION ELEVATIONS: 525'-527' (3' MAX.)
1xWQV REQUIRED BETWEEN ELEVATIONS 518'-525': 1,079cf
WQV PROVIDED BETWEEN ELEV1'ATIONS 518'-525': 3,725cf
1xWQV REQUIRED BETWEEN ELEVATIONS 525'-527': 1,079cf
WQV PROVIDED BETWEEN ELEVATIONS 525'-527': 9,0094
06" INVERTED PIPE UPSTREAM IINVERT INTO RISER ELEVATION= SHALLOW MARSH ELEVATION= 525' FOR ENHANCED EXTENDED DETENTION
06" INVERTED PIPE SHALL HAVE: A SCREW CAP AT THE RISER w/ A 03" ORIFICE OPENING
TOP OF 036" RISER ELEVATION= EXTENDED DETENTION WATER SURFACE ELEVATION= 527' FOR EXTENDED DETENTION
20' EMERGENCY SPILLWAY ELEVATION= RISER ELEVATION= 527'
030" BARREL OUTFALL STRUCTURE INTO EXISTING TOWN CENTER DRIVE DI: 109 LF @ 1.74%, INVERT IN=521.9 & INVERT OUT=520'
TOP OF DAM ELEVATION= 528'
172X0%;;%£for IS01% EEC Rem0c 0[U
`
<
0�
° •o
.a�drtiortal t± ester O ality N;`olu,me Prcdi� 'd - 2,�,� of
�"a
�
i—d
CDU
Wz
'►y
EC
w c
o
zU
L o
w -o
z
W
J �
0 16
0
?
L 0
o
Q U
O �
s2 �
;o
.N
o
0
X -0
PROFFERS FROM ZMA 1992-14 FOR TMP 03200-00-00-05600
1. THE MOBILE HOME PARK IS PROFFERED FOR A PERIOD OF NOT LESS THAN FIFTEEN YEARS FROM THE START OF THE DEVELOPMENT IN
.
0 0
ACCORDANCE WITH THE COMPREHENSIVE PLAN, DURING THAT PERIOD OF TIME, THE PROPERTY SHALL NOT BE AVAILABLE TO ANY OTHER
m
R-15, RESIDENTIAL USES EXCEPT NOTHING CONTAINED HEREIN SHALL PROHIBIT THE ZONING ADMINISTRATOR FROM AUTHORIZING USES
0 7,
DEEMED ACCESSORY AND SUBORDINATE TO THE MOBILE HOME PARK. IN THE EVENT THE CONDITIONS OF SP -93-13 ARE NOT MET, OR AT THE
w
E
TIME OF EXPIRATION OF SP -93-13 IN ACCORDANCE WITH SECTION 31.2.4.4 OF THE ZONING ORDINANCE, THE APPLICANT SHALL PERMIT THE
,C3
o
PROPERTY TO BE REZONED TO RA, RURAL AREAS, BY THE BOARD OF SUPERVISORS AND THEREAFTER THE PROPERTY SHALL ENJOY ALL RA
tY
o -
USES. FOR THE PURPOSES OF THIS PROFFER, THE TERM "START OF DEVELOPMENT" IS DEFINED AS THE DATE OF ISSUANCE OF THE FIRST
Ln
° D
MOBILE HOME BUILDING PERMIT. NOTHING HEREIN SHALL PROHIBIT THE BOARD OF SUPERVISORS FROM GRANTING AN EXTENSION OF THE
JOB NO.
EXPIRATION DATE OF SP -93-13 IN ACCORDANCE WITH SECTION 31,2.4.4 OF THE ZONING ORDINANCE.
5, SHALL
102036
0
2. THE FRONTAGE OF ROUTE 29 CONTAINING TAX MAP 32, PARCELS 43A, 43, 42E, 42D, 42B, 42C, 42A AND TAX MAP 46, PARCEL
CONTAIN NOT MORE THAN THREE ENTRANCES. THE COUNTY MAY REQUIRE CLOSURE OF ANY EXISTING ENTRANCES AT THE TIME OF
N o
ESTABLISHMENT OF ANY NEW ENTRANCE SUCH THAT THE TOTAL NUMBER OF ENTRANCES DOES NOT EXCEED THREE.
SCALE
3. AN ACCESS ROAD BETWEEN THE MOBILE HOME SALES AREA AND MOBILE HOME PARK SHALL BE DEVELOPED AT THE TIME OF ESTABLISHMENT
a
OF THE MOBILE HOME SALES USE. THIS ACCESS ROAD SHALL BE USED ONLY FOR THE MOVEMENT OF MOBILE HOMES BETWEEN THE TWO
AS NOTED
a �
USES AND FOR EMERGENCY ACCESS.
CONDITIONS FROM SP 1993-14 FOR TMP 03200-00-00-05600
SHEET NO.
o�
n
1. THE INVENTORY SHALL INCLUDE MOBILE HOMES WHICH MEET THE NOISE ATTENUATION STANDARDS OF ZMA-92-14.
5>
Qa
� o
TH ItIIitSCOTT R. COLLINS�?,
0
U No. 35791 tAPPROVED SWM -777—�
- ---- - FA TY- N -PART IOT
. . . ...... . ... WIVI . ..... . ... . ........ ----- ------- OINVAL . ......... ------ ----- - t-- ----- ----- I--- ------ -- (BIOFILTER #1) THIS DEVELOPMENT 'ST -SE N IN G- -ORM �b k APPROVED S -THIS-DEVEL9RVENT-' (BIOFIL:TER,#2) FACILITY- NOT PART OF ,TO17r OROS D I. . . . ..... r - - ------ -- IVP IDE EL M E N I"STORMWA
ILA 0 T IEXISTING
IDRAINS To APPROVED.-.--. T Rl`0FIl TE #,9 LOCA ED 0.1! IIANAGEMENT FACILITY #2"
TER ------------ :-4 i TMP032B-oo-oo-000Ag I- - - - ---------------------- -- - - - --------- -- - -- ---- -- - ----- sz
HIS',� - ----- - -- ---- I------------- - - - ---------- -- - --- - -------- 0
UEV -------------- ----- -- ------- -- N T PART T . .... - - ------ I , _ f � ! I / "I I I "" /M
II0 'O
BIC, I---------- �A E L Q IVI E 1, IU 2:
-- - ------------ ILU
---------- I<
I0 Z . .. ....... . IEXISTING SEDIMENT tM z
IBE CONVERTED To = , it" BASIN PROPOSED TO II--- ------- - ----- EXISTING DEVELOPMEN-1 V , ...... . ....... DRAINS TO APPROVED 8 --------- -------- 7' ----------- .......... ------------ I- ----- SWM FACILITY #3 A ------- IUJ
I LTER #i LOCATED ON Ce
.,,-BIOF IIPAR T P - - ----- - --- tYRM El IIE R STORM SEW .. . ........ . EVELOPM F tEXISTING IE -0,TH IDRA IN, ING F IW "NOIRtH - ----- ------- 1 0 EXISTR G S��M — - - ------ - ------------------------- -1 , - -/ N / I I I - ", , I
/ EN ........... ...... . . ...... I�i(#211LOC#T IE-01bN I----- ----- ---------- I--------- -- ----------- I -PA 7 DEVELOPMEK tT ?2 < - r
trI r I------ - - - ---------- ----- - - ----- IIII------- - --- .... .. ..... . ----- - .... . - ----- ------ . ....... ------ -------- - . .......... ..... .. ------ W W/ I? I Tf T - ------ -- - ItItI- ----- ------ ----- - - — --------- - ------- -- ---------- - - ------------- - ------------ - -- — — --------------------------------- - - - - - -- - - - --------- ;77, I... ... ... ... .. IMEER=
I-------------------- I-------- w M M Im ON - -M
- - - ------- - - I. ..... ... ....... - --------- CL -- - ------- IU
tII0 LL I---- - - ... .. TING 0 IQ) Of
IL
IIL
POCH L
IV
IIILLJ
IC
....... CL IC
UJ
UJ OVERLANDI FLOW --400' W/ LU
I0 Short Version BMP Computations For Worksheets 2 - 6 min.
cl) :t
A ELEV.�2'(Tc=13 L9 IDA #2: ——,CONCENTRATED FLOW= Albemarle County Water Protection Ordinance: Modified Simple Method i 1 I-1, 200 W/ < I(ANALYZED AS 50A. z
50% LAW#�) A ELEV. �47'(Tc=6 mW WOODS/ ICHANNEI�,FLOW wi�AN Plan:- Holly -mead Town Center Water Resources Area: Development Area 370' CN= 58 >
IESTIMATED VELOCITY=5fPs 11 4&w( Preparer: FroM, PE Date: 19 -Sep -13 C (Tc=i min.) Q
:3
-0
0
FINAL Tc 20 min. C= min. LU T I2
Project Drainage Area Designation DA*1 L storm pol[utant export in pounds, L [P(Pj)Rv/12 f C(A)2.721 0 lop' Rv mean runoff coefficient, Rv M5 0.009(l)
small storm correction factor, 09 0 0 Pi IE I percent imperviousness
. . ........ annual precipitation, 43" in Albernarle P
'A project area in acres in subject drainage area. A= 11-44 C
--------- Ul asphorus C pollutant concentration, mg)t or ppm target ph
Ii f factor applied to RR [if z LJ C
s- ------ ----------- r irripery Ld V required treatment volume in cy, 0.5" ove -area= A(1)43500(0-5�12)/27
-- -- - ----- LU
\7 RR required removal, L(post) - f x L(pre) - - -- --------- - C
--------------- ',,.RR removal efficiency RR1 00/L(post) UJ -C
CL- ------------- C
IsSTORM SEWER DR Impervious Cover Computation (values in feet & square feet)
—J ANIN II1tem —T ------ LU 0 -XtSf1' -SW' C4 1 0 E NG M, -development IArea -development 'Area LITY post ---FACI -.-LOCATEDON,-` F pre
subtotal subtotal -oo-oo-oo5oo TMP04600 90, Roads, Alleys & Driveways Proposed RoadslAlre�,ways!Dnveways ------- C
& 35,000 '(N OT PART -0 FTt4l S P LAN) ------- -- -- ;Existing Lockwood, Town Cen, LJJ
. . .... .. ... .. Meeting St- 0
- ------------- CL I0 125,000 --- 4
. . ...... .. . .. .. ... .... . ...... C
'Gravel areas Area Gravel Areas in
x 070 0 070 0 CITES: —C) Structures subtotal Structures subtotal X
TO EXISTING SWM IIISTORM SEWER DRAINING
SWM NARRATIVE/N
PER THE NEIGHBORHOOD MODEL DISTRICT ZONING & PROFFERS APPROVED ON 9/12/07 FOR M FACILITY LOCATED ON P E
IZMA-2007-001, AN ADDITIONAL 20% PHOSPHOROUS REMOVAL RATE SHALL BE PROVIDED FOR TM t0! 0 TI\/fR046o6-oo-oo-oo5oG- 03200-00-00-04500- SWM FACILITY #3 RECEIVES DRAINAGE FROM THIS PARCEL AND REQUIRES A �Acflvely-grazccl pasture & Area sAre a (NOT PART OF TH�S,PLAN) REMOVAL RATE EFFICIENCY OF 30% WHEN TAKING INTO CONSIDERATION THE EXISTING 373,326 x 0 08 29,866 cn
166i 498,326:xG.0R- :yards and cultivated turf AL uActjve c4 Area Area
op land U 2o% ADDED THE REQUIRED REMOVAL RATE FOR THIS FACILITY IS So% TOCOMPLYWITHTHE IMPERVIOUS AREAS & g0000sf OF FUTURE IMPERVIOUS AREAS. HOWEVER, WITH AN ADDITION 0" :x 0�26 — 0 LU
t E
H t SCALE 025
T PROFFERS THIS PLAN PROPOSES A TYPE 11 RETENTION BASIN WITH A REMOVAL RATE EFFICIENCY 0 LLJ
C) — --- - Other Impervious Areas tI0 0
fl. En
24G OF 50%- I 'A' I ... 111 - -0 C
r i - -------- 'Impervious Cover 31 'yo: JOB NO. l(post)
. ....... .... [(pre) C) IS DESIGNED TO HANDLE AN ADDITIONAL 20,00OSf OF FUTURE IMPERVIOUS AREA FROM A 0
IN THE EVENT THE FUTURE DEVELOPMENT EXCEEDS go,000sf OF IMPERVIOUS AREA, THE FACILITY
DETENTION STANDPOINT. SHOULD THE FUTURE DEVELOPMENT GENERATE AN IMPERVIOUS AREA -EET IN -F
------ SCALE
BETWEEN 9o,000-:Li0000sf A FILTERRA INLET(s) WILL NEED TO BE INSTALLED TO PROVIDE WATER Rv(post) V lqqw*
1 =60 QUALITY FOR THE 20,00OSf OVERAGE. OM 2
.......... & New Development (For Development Areas, existing impervious cover <= 20%)
-------- -- I (pre) Rv(pre) % RR Area Type
SHEET NO.
REGARDLESS OF THE FINAL BUILDOUT IMPERVIOUS AREA, THE FACILITY IS DESIGNED TO TREAT I'T L(pre) L(post) RR
f C Q) (
5 00 30% Develop ment Area
6
3 1154� 16-94 CENTER DRIVE & MEETING STREET.
DETAIN THE EXISTING ROADS. THESE ROADS INCLUDE PORTIONS OF LOCKWOOD DRIVE, TOWN
I...... . .. r , , ; , , ,
Imin- values C
s
itIIH 0
tSCOTT R. COLL S
U No. 35791 IIN
�AP ROVED SWM FACILITY- NOT PA T OF ---- --- ------ HI-S--DEVELOPMEN-T-' - ------- APPROVED SWM -------- ---- F BIOFILTER#2)-- 10NAL t
M- ----- ------ ...... ....... IONAL
-, 0 -b�w ACILITY- NOT PART OF THIS DEVELOPMENT (BIOFILTER #i),, /* tI --------- -
fIEXIPTIN DEVELOI�M, ---------- EXISTING "STORMW
IfANAGEMENT FACILITY #2"
1 — — --------- --------------- TO APPRVEb . .. ....... T- -- ------ - -- it: I ; L I........... LK;P2 LO,C j�p OM M
ATER ITMP03 fNG, LEVE�c'TOP OF OAM---' -oo-99-000Ao: .... .. ... ---- ------- .............. - - ------- ----------- t(Nu I PA z
------------ AY� EAS, EM E N 0 ------------- HALL SERVE AS ACCESS T RT OF THIS"
�Q-P OF DAW&�DOWS LUJ 0 f---------- DEVELUVWILIVI) SWM FACILITY #3. f- ----------- R A] N _CONSTRUCTION QkING §�'UkbED D - ------------- ....... . ... .... ca
;-��QPPSED SWIM FACIIITY-,#� SH -BE Lu :D
. .... ... .. ........... ............. tt. .......... . <
- --------- UJI . . ...... ... ..... ---------- Ivim ---------- SEDIMENT z
REGRADED INTERI\�A TO HAVE A FOREBAY & A MINIMUM OF LL -------- ----- 2:1 SIDE SLOPES (AS SHOWN) r C D 7 UTILIZE EXISTING 3o" R iIIBARREL MODIFY 048" R I- - --------- RISER PER THE PLAN C P -------------- ---------- EXIS 0 I- ----------- ...... .. . . ........... rj 11 --- - - --- - ----------- - ------ ----------- ------------- PMENT� uj
------------ - ---------- - -- ------ . .............. DRA�&S TO APPROVED --- ------ - - - ----- - --- ---- - ------ - - - ----- - -------- - �y Po3 t--------- - LOCATED ON -------------------- ce
FILTER # r tRf b''F" f H. 1 ID VEL(j IIRif" EXISTING TOWN CENTER EWE DRIVE SHALL SERVE AS STORM S' ACCESS TO SWM --- - ------ .. .... IDRA4 ING �TO,T.A!E -- - --- --- - > /-,�,�ISTIN 0EVELOPMENTEY FACILITY #3 - --------- -- - - ---- t....... ..... DRAIN fTO EXISTI G SWM .. . . ....... -- — ----- ..... . .... -- ----- - -- V h- t. ....... .... . ----------- CIL Tyd(#2)iLOCA-T1EDjON 11 II- - -- - ----- K ifba-boo - --- ---- -- - ---- - ----- 4- IC)
- ------ -- OT -PART -O V FTHtS H k FA I..... ........ . ----------- -------------- DEVEL9RME'. IIftItt. ......... - -------- - - t_J itII----------- t---- - ----- - - --- --- ----- -------- -------------- ----- --------------- -7 - -------- I--------------------- ItI ry')
------ ----- - - I-- --------- ----- - ............ --------- - -- I- -------------- - ----- - - ---- -------- - -- - -- -------- ---------- --- - ------ it- - --------- ------------------ -- ICL I----- ----- -- ------ -- --- ------ u-
IitIf 06
cn LLJ
LLJ
I.... .. ...... r- V)
ce. z
IDA #2: Lu
Z(V�A TER QUALITY& DETENT19N'CREDIT FOR I90,000sf OF FUTURE -IMPERWOUS AREA & AN ADDITIONAL DETEN77ON CREDIT OF,, U
20,000sf Fdk FUTURE IMPERWOUS AREA) ILu ICN= 7i.8 U.1
uj
11-440—C. Tc=-io min. tIul
L9
It<
r>7 x
ItIfIuj
II0
iC,- II..... .. ... ---------- - 0
t--------- -- I--- --- ---- . ..... t . .......... ... ---------- ........ .. .......... .. -- ----- - ------ ----- ---- . ......... . .......... ----------- ILLJ 0
------ --- - ------ - uj Ld
- - ------ --- - - - - - ----------- - ----- -- - - - - - — ----- - ---------- -t ILIJ
----------- I - -- --- ------ - 0
. .... ..... IIIu I---------- . ......... Ul Lu
7 -G STORM SEWER DRA .. ..... LLJ it0-0
--OC FACILITY, -L A -oo-oo-oo 00 -SW -TO EXTSTfNG -TM7004600
IOFTI41S PLAN— i(NOT PART IC) U
------------ 0 ::3
- ---------- ICL ftI> 0
1 Q)
in
itSTORM SEWER DRNING TING SWM tTO EXIS IFACILITY LOCATED ON IE
-------- - --- I-oo-oo-ooSoo TM P046o6 tII(NOT PART OF THIS,PLAN) 0
titu titUJI >
- ---- ----- I0 6)
ifuj
E it- --------------- --- -- -------- f-- ------- - --- Z7' JOB NO. I- - - - - --------- I------------- -- --------- ------------ 0 >
102036
co 0 V)
SCALE
G A U IC SCALE p I t ...... Watershed Summary Pre -Development Post- Develo pme nt 60 3 60- 4 I
Area
Description (acres)
2 -Year Outfall
CN (cf S)
10 -Yea r Outf a I I
(cf S)
Area
(acres) C N
2 -Yea r Outf a 11
(cf S)
10 -Year Outfall
(cf S)
IfOIL--
58.0 4.30
15 55
11 44 7J 8
3.58
1481
-=
Itit7,
t
Area
Description (acres)
2 -Year Outfall
CN (cf S)
10 -Yea r Outf a I I
(cf S)
Area
(acres) C N
2 -Yea r Outf a 11
(cf S)
10 -Year Outfall
(cf S)
D.A. #2 11.44
58.0 4.30
15 55
11 44 7J 8
3.58
1481
Tota 1= 11.44 4.30 15.55 11.44 3.58 14.81
cn
SHEET NO. 7
771,E /'1�T�' T y�r(� � �'T
1 II III, t SW ly1 FACIL17Y#3 DL 1111L
f
(TYPE HRETENTION BASIN- 4xWQV}
r
SCALE 1 30
AE
t ` _1iFj-I-I ' r f \ VARI BLE WIDTIL t `
i Al 11 !
SW EAS MENT, f " !
Ilgfl rr UTILIZE EXISTING 'RADED,`-
1ACGESS ROAD `& EMBANKMENT � ; " �! 'f
17R DED ACCESS ROAl` SHALL BE
iii-lI -1
MIN. OF 10' WIDE & Sh;.4LL ;y \
1 _ i �VE SLOPES <f 10%, AS S TOWN
t i EFUT �f ON TH PLANS.
r,
'
"
E' P l/
I
f'
Z\
Jtft
r
..,,'Mffl
= III;
- =11I
.' +t r
CONTRACTOR
f,.
;
,f
� r ;
r %
t 11� AL VERIFY
EXISTING 10' WIDE
(MIN.) TOP OF
_
=111= DAM ELEV. - 523' �_ ✓ ,>. `
111 f-
,
r`
;11=1i�1e t ,,C
r=Z ( EXISTING DOWNSLOIIV
MBAI;IKMENT & BAI- EL /
.��I
i'I I UTFrLL SHALL RE / r f.
- - j
UNDISTURBED DUI
,r
,f si 1 �li
1Ll
CONSTRUCTION. 1' J
1E ISiT
TING '
t�
au
R P=RAP
fiFALL ` r I I� I I-
3 r f i / .•%,
{ a _ %: i MII�? WATER/QVALITY'Y1jLUME
1: ISI t
n?•
;.n wp v EXIS/`IIl�JC{ j.3III dtj t f 'J \ \ a
u ,f
UTI IZE XIS2I G ' Its' D,:• 4z - I'VO C
7 ENDWALZ, fJ �11T_i-T f� WA �iUAL�1 `VOLUME
i 30,,, RCP xi 1 EAS l 39, 394c r r,`
V3'D
, f •f
f
s �✓
,
Sediment Basin Conversions to SWM Facilities:
When the SWM facilities are converted from the existing sediment basins, the conversions
to the permanent facilities shall only occur afterfinal stabilization and approval from the
County inspector has been granted.
Priorto regrading these facilities the contractor shall dewaterthe wet storage area in accordance with
current County and State regulations. Sediment and other debris shall be removed to a contained spoil
area.
Once sediment laden material has been excavated the contractor shall regrade the basin per the
proposed plans. An adequate topsoil layer shall be applied to the final grade to promote final
stabilization.
The proposed modifications to the riser structures for SWM facilities #1 & #3 are required as part of the
conversions to the permanent stormwater facilities. The removal of the existing riser structure, the
abandonment of the existing barrel and installation of the proposed outfall configuration for SWM
facility #2 is required as part of the conversion to the permanent stormwater facility. During the
modifications to the riser structures for SWM facilities #1 and #3 the contractor shall ensure the
structural integrity of the riser is not threatened and large construction equipment is not utilized within
the basin.
Any heavy construction work required with the regrading of the facilities shall be conducted prior to
modifying the risers for SWM facilities #1 & #3. Under no circumstance shall construction adversely
affect the structural integrity of the existing embankment for any of the three SWM facilities. Also,
under no circumstances should the structural integrity of the risers and barrels being modified for SWM
facilities #1 & #3 be compromised. Should the structural integrity of any of these items be compromised
the contractor shall replace the structures in accordance with current County and State regulations. The
contractor shall also ensure the risers are embedded 6" into an 18" deep concrete base with a diameter
at least twice the diameter of the riser structures. Modifications to the existing risers shall be made if
such a configuration is not already present. After final modifications and installations to the riser
structures have been made the contractor shall ensure the riser sand barrels are watertight and are in
compliance with the approved plans. The contractor shall also ensure the embankment is functioning
properly.
Once final grades have been achieved and modifications to the outfall structures have occurred,
inclusive of the installation of emergency spillways if applicable, the contractor shall install final
landscaping and stabilization in accordance with the approved plans. Forthe conversion of the sediment
basin to the Enhanced Extended Detention Facility, SWM #2, establishing vegetation may prove
difficult if flow is routed through the facility prior to germination. In such cases, the contractor shall
install sod or other reinforcements for the basin bottom and shall ensure adequate vegetation has been
achieved.
' RIP -RAP
OUTFALL
t
RETENTION BASIN REQUIREMENTS:
Credit for Future Developmentflmpervious Area 90,000 sf
Existing Impervious Areas being Treated= 35,000 sf
Water Quality Volume
5,208 cf
Water Quality ''volume Required
20,833 cf
(50% Removal= WQV x 4)
Area (acres)
Elevation Area of Wet Fond
CN
71.800
Volume (cf)
(ft) Contours (sf)
rainfall, P (in)
3.700
time of cone (hrs)
5,112 5,709
9,'9- 03
aFP r,385
22,961
X16 9,(;j`
39,394 _.
`I3 10,3",,5
59,271
520
82,994
CO.2 15,488
111,374
23 ? ;' ,7
127.372
3
MIN. REQUIRED WQV
(4x)=20, 8JJcf
WQV PROVIDED=39,394cf
EXISTING
RIP -RAP
BOTTOM OF
PROPOSED FOREBA Y
ELEVATION= 510'
PROPOSED BO TTOM OF
RETENTION BASIN= 510.00'
Basin Input Data
BasinFlow printout
INPUT:
Basin: Hollymead Town CenterTH Retention Basin
8 Contour Areas
Elevation(ft) Area(sf) Computed Vol.(cy)
510.00 4231.00 0.0
512.00 5709.00 366.8
514.00 7385.00 850.4
516.00 9077.00 14590
518.00 10825.00 2195.2
520.00 12930.00 3073.9
522.00 15488.00 4125.0
523.00 16513.00 47175
Start-Elevation(ft) 516.00 Vol.(cy) 1459.04
CONTRACTOR SHALL ENSURE
PLUG E&S DEWATERING ORIFICE, EMBANKMENT CONTAINS AN EXISTING
MODIFY EXISTING 048 RCP RISER IMPERVIOUS CORE w/ CUTOFF TRENCH
RIM TO ELEV=519.0' & INSTALL UTILIZE EXISTING /N ACCORDANCE wf THE DETAIL
THREE PROPOSED 06" LOW -FLOW 030" RCP (INV. IN= SHOWN ON SHEET 4.
ORIFICES ® ELEV.=518.0' 510.42 & INV.
OUT=508.41)
TYPE IT R.E'T.ENTION BASIN
(NOT TO SCAB'/
Outlet Structure
3 Outlet Structures
Outlet structure o
Culvert
name:Existing Barrel
multiple 1
discharge out of riser
D (in) 30.000
h (in) Moo
Length (ft) 66.600
Slope 0.030
Manning's n 0.013
Inlet coeff. Ke 0.500
Equation constant set 3
Invert (ft) 510.420
Outlet structure 1
Curve
name:Existing Modified Riser -
Anti -Vortex Device
multiple 1
Invert (ft) 519.000
discharge into riser
file: fortyeight.txt
Outlet structure 2
Orifice
name: Proposed Low Flow Orifices
area (sf) o.196
diameter or depth (in) 6.000
width for rect. (in) 0.000
coefficient o.600
invert (ft) 516.000
multiple 3
discharge into riser
100 YEAR
W.S.E. =520.70
1 ---PROPOSED TOP OF 10 YEAR
W.S.E.=519.50
FOREBAY DAM WIDTH= 3' 2 YEAR
AT AN ELEVATION= 516' %^WS.E.=517.84
5$ WEIR
COEFF. _
3.3
RIPRAP LINED FOREBAY -'
WEIR CREST ELEV.=51,2'
FIJREBAYSPILLWAY
NTS
Inflow Hydrographs
3Inflow Hydrographs
2- Year, SCS 24-hour Storm
Distribution
Area (acres)
11.440
CN
71.800
Type
2
rainfall, P (in)
3.700
time of cone (hrs)
0.1700
time increment (hrs)
0.0200
time limit (hrs)
6o.000
fudge factor
1.00
routed
true
peak flow (cfs)
16.073
peak time (hrs)
11.961
volume (cy)
1907.688
10- Year, SCS 24-hour Storm Distribution
Area (acres)
11.440
CN
71.800
Type
2
rainfall, P (in)
5.600
time of cone (hrs)
0.1700
time increment (hrs)
0.0200
time limit (hrs)
6oi.000
fudge factor
1_.00
routed
trine
peak flow(cfs)
341•328
peaktime (hrs)
1u.961
volume (cy)
4074r.340
loo -Year, SCS 24-hour Storm [Distribution
Area (acres)
11.440
CN
71.800
Type
2
rainfall, P (in)
9.100
time of cone (hrs)
0.1700
time increment (hrs)
0.0200
time limit (hrs)
6o.000
fudge factor
1.00
routed
true
peak flow (cfs)
73.110
peaktime(hrs)
11.961
volume (cy)
8677.384
I-IANSON CONICRETE
ANTI -VORTEX TRASH
RACK
Routing Method: storage -indication
2- Year, SCS 24-hour Storm Distribution
inflow (cfs) 16.072 at 11.96 (hrs)
discharge (cfs) 3.575 at 12.22 (hrs)
water level (ft) 517.84o at 12.22 (hrs)
storage (cy) 2131.6o1
10- Year, SCS 24-hour Storm Distribution
inflow (cfs) 34.325 at 11.96 (hrs)
discharge (cfs) 14.8o6 at 12.12 (hrs)
water level (ft) 519.498 at 12.12 (hrs)
storage (cy) 2838.582
loo- Year, SCS 24-hour Storm Distribution
inflow (cfs) 73.1o3 at 11.96 (hrs)
discharge (cfs) 59.513 at 12.04 (hrs)
water level (ft) 520.701 at 12.04 (hrs)
storage (cy) 3420.929
CONTRACTOR SHALL
VERIFY EXISTING 10'
WIDE (MIN.) TOP OF
DAM ELEV.= 523'
Nj \ 7
--TRASH RACKS SHALL BE INSTALLED
ON ALL ORIFICES PER 77 -IE DETAIL
SHOWN ON SHEET 4, OR EQUIVALENT
-ORIFICE COEFF = 0.6
_-_-----PLUG E&S DEWATERING ORIFICE,
MODIFY EXISTING 048" RCP RISER
SH 07I�
SCOTT R. COLLINS,
U No. 35791
��SSroNAL E�o�
RIM TO ELEV.=519.0 & INSTALL
THREE PROPOSED 06" LOW -FLOW
ORIFICES 0 ELEV.=516.0'
a.
_J//
UTILIZE EXISTING 030"
CONTRACTOR SHALL ENSURE RISER
RCP (INV. IN= 510.42 8c
ISS EMBEDDED 6" WITHIN A MIN. 18"
INV. OUT=508.41)
7HICK 08' CONCRE7F BASE
PRINCIPAL SPILLWAY
NOT
TO SCALE'
SH 07I�
SCOTT R. COLLINS,
U No. 35791
��SSroNAL E�o�