HomeMy WebLinkAboutWPO201700052 Plan - VSMP 2021-06-29DUNLORA OVERLOOK
��c O�nloa pr
Q�
GENERAL NOTES
OWNER/APPLICANT. 06100-00-00-16500
DUNLORA INVESTMENTS, LLC
455 SECOND ST SE, SU1 TE 400
CHARLOTTESWLLE, VA 22902
ENGINEER: COLLINS ENGINEERING
200 GARRETT ST, SUITE K
CHARLOTTESOLLE, VA 22902
(434)293-3719
SURVEYOR: CARDINAL SURVEY
TAX MAP PARCEL: 06100-00-00-16500 (DB 4657 PG 413)
TOTAL PROJECT AREA: 8.62 ACRES TOTAL.
ZONING. R-4 RESIDENTIAL (BY —RIGHT) — NO PROFFERS
AIRPORT IMPACT AREA (AIA)
PROPOSED USE: 15 SINGLE FAMILY ATTACHED UNITS AND
14 SINGLE FAMILY DETACHED UNITS
REQUIRED DENSITY: 4 DU/AC
PROPOSED DENSITY- 29 DU/8.62 AC = 3.36 UNITS/AC
OPEN SPACE.• REQ: 2.16 AC OF TOTAL DEVELOPMENT AREA 8.62 x 25%); AND
207 OF THE REQUIRED OPEN SPACE SHALL BE OUTSIDE OF CRITICAL
SLOPES AND THE SWM FACILITY
PROV.• 3.20 AC TOTAL OPEN SPACE PROVIDED (37%)
1.47 AC PROVIDED OUTSIDE CRITICAL SLOPES AND THE SWM FACILITY
(46% OF THE REQUIRED OPEN SPACE)
THE OPEN SPACE WILL BE DEDICATED TO THE HOA.
BUILDING HEIGHTS: MAXIMUM BUILDING HEIGHTS SHALL NOT EXCEED 35 FEET
NON—INFILL SETBACKS: FRONT: 5' MIN AND 25' MAX
SIDE. • 10' BUILDING SEPARATION
REAR. 20' MIN AND NO MAX
SITE AMENITIES 2.63 ACRES OPEN SPACE (PASSIVE RECREATION AREA)
SUBDIVISION STREETS: CURB & GUTTER (PARKING ON ONE SIDE ONLY)
WATERSHED: THIS PARCEL IS NOT IN A WATER SUPPLY PROTECTED AREA — SITE
DRAINS TO MEADOW CREEK (UPPER RIVANNA WATERSHED)
AGRICULTURAL/ FORESTAL DISTRICT: NONE
TOPO & SURVEY. ON —GROUND SURVEY PROVIDED BY CARDINAL SURVEY IN SEPTEMBER 2016, AND
FROM DEEDS AND PLANS OF RECORD.
DATUM: NAD 83
EXISTING VEGETATION: PARTIALLY WOODED WITH EXISTING RESIDENCE STRUCTURES
CRITICAL SLOPES. MANAGED AND PRESERVED STEEP SLOPES ARE SHOWN AND LABELED.
LIGHTING. NO LIGHTING IS PROPOSED
PHASING: SITE TO BE DEVELOPED IN A MINIMUM OF ONE PHASE.
UTILITIES: PUBLIC WATER AND SEWER
FIRE & RESCUE. • AS REQUIRED, ALL FIRE FLOWS WITHIN THE DEVELOPMENT SHALL BE A MINIMUM
OF 1000 GPM AT 20 PSI. ADDIT70NALLY, FIRE HYDRANTS SHALL BE PROVIDED
ALONG THE ROADWAYS FOR FIRE PREVENTION AT A MAXIMUM SPACING OF 500
FT PER TRAVEL WAY.
RECREATION. NOT APPLICABLE/NOT REQUIRED
PARKING: 2 OFF—STREET PARKING SPACES SHALL BE PROVIDED FOR EACH DWELLING UNIT
t 4 ON —STREET GUEST SPACES (MIN) FOR THE ATTACHED UNITS. 6 ON —STREET
GUEST SPACES SHALL BE LOCATED ALONG THE ROADWAYS WHERE MARKED.
BUILDING SITES: PARCELS 1-29 MAY NOT BE FURTHER DIVIDED. ONLY (1) DWELLING UNIT PER
LOT SHALL BE ALLOWED.
BURIAL SITES: NONE
STREAM BUFFERS/FLOODPLAIN. THERE IS A PORTION OF A WPO STREAM BUFFER LOCATED AT THE
SOUTHEAST CORNER OF THE SITE. THERE IS NO 100—YEAR FLOODPLAIN LIMITS
ON THE SUBJECT PARCEL, PER FEMA MAP 51003CO229D; FEBRUARY 4, 2005.
OFFSITE DISTURBANCE: NO OFFSITE DISTURBANCE IS PROPOSED WITH THIS PLAN, EXCEPT FOR THE
TIE—IN CONNECTION TO THE SANITARY SEWER WITHIN EXISTING UTILITY EASEMENT.
LANDSCAPING. ALL PROPOSED ROADWAYS SHALL HAVE STREET TREES IN ACCORDANCE WITH
ALBEMARLE COUNTY REQUIREMENTS, PER SECTION 32.7.9 OF THE ZONING
ORDINANCE.
RETAINING WALLS. THREE SEGMENTAL RETAINING WALLS WERE ORIGINALLY APPROVED.
SIGNAGE.• NO SIGNAGE CURRENTLY PROPOSED.
TRASH COLLECTION: TRASH RECEPTACLES SHALL BE MAINTAINED ON EACH INDIVIDUAL LOT ALL
TRASH SHALL BE COLLECTED BY A DRIVING DUMPSTER SERVICE.
DAM INUNDARON. THIS SITE IS NOT WITHIN A DAM INUNDATON ZONE.
NorGF1
STORMWA7ER MANAGEMENT. • STORMWA7ER WILL BE CONVEYED TO A LE�E6--�,6*Tu 1
-FER—..�,T�
DOWNSTREAM DETENTION BASIN ""'^ " ^R" ^`T`"'T'^"' ^""'"' SEE SWM PLAN
FOR DETAILS
IMPERVIOUS AREAS. SEE PROPOSED & APPROVED SWM SHEETS
LAND AREAS.
OPEN SPACE.• 3.20 AC. (31 %)
LOTS 4.26 AC. (557)
ROW DEDICATION. 1.16 AC. (147.)
TRAFFIC GENERATON: TRIP GENERATION BASED ON ITE GENERATON MANUAL (8TH EDITION)
29 SINGLE FAMILY UNITS (CODE 210)
278 VPD (139 EN7ER/139 EXIT)
AM PEAK. 22 (6 ENTER/16 EXIT)
PM PEAK: 29 (19 EN7ER/10 EXIT)
LEFT/RIGHT LANE TURN WARRANT ANALYSIS:
DUNLORA ADT = 2300 ADT
VPH = 2300 / 12 hrs X 2 = 400 VPH (WORST CASE)
NOTE: THE LOCATION OF THIS ENTRANCE IS BETWEEN (2) ENTRANCES INTO DUNLORA, ONE
ENTRANCE FROM RIO ROAD/PARK STREET, AND THE OTHER ENTRANCE FROM RIO ROAD/✓OHN
WARNER PARKWAY. WITH THE (2) ENTRANCES SPLIT77NG THE APPROACHING TRAFFIC AND
TRAFFIC LEAVING DUNLORA, THE VPH WILL ALSO BE LESS AT THIS ENTRANCE LOCATION.
RIGHT TURN WARRANT. • PEAK PM IS THE HIGHEST TRIP PER HOUR WITH 21 ENTERING THE SITE
BASED ON THE CHART IN THE VDOT MANUAL ON PAGE F-96, 21 CARS AN HOUR ENTERING THE SITE
WITH AN APPROACHING TRAFFIC VOLUME OF 400 VPH DOES NOT WARRANT A RIGHT TURN LANE OR
FULL TAPER. A 4: 1 TAPER INTO THE DEVELOPMENT HAS BEEN PROVIDED.
LEFT TURN WARRANT. • BASED ON THE CHART IN THE VDOT MANUAL ON PAGE
F-78, A VOLUME OF 400 VPH ADVANCING VOLUME AND 400 VPH OPPOSING
VOLUME DOES NOT WARRANT A LEFT TURN LANE. THESE VPH VOLUMES ARE A
WORST CASE SCENARIO AND DO NOT TRIGGER THE REQUIREMENTS FOR A LEFT
TURN LANE.
NOTE. EACH LOT AS SHOWN HEREIN SHALL CONTAIN A BUILDING SITE WHICH MEETS THE REQUIREMENTS
OF SECTON 4.2.2(b)1 (18-520)
VSMP AMENDMENT #3
WPO 201700052
(AMENDMENT #3 TO WPO 201600058)
RIO MAGISTERIAL DISTRICT ALBEMARLE COUNTY, VIRGINIA
SCALE: 1"=60'
OWNER
DUNLORA INVESTMENTS, LLC
455 SECOND STREET SE, SUITE 400
CHARLOTTESVILLE, VA 22902
ENGINEER
COLLINS ENGINEERING
200 GARRETT STREET, SUITE K
CHARLOTTESVILLE, VA 22902
VSMP AMENDMENT #3 PROPOSED CHANGES:
, THE PREVIOUSLY APPROVED BIORETENTION BASIN HAS BEEN REMOVED WITH THIS
AMENDMENT AND WATER QUALITY REQUIREMENTS WILL NOW BE MET WITH A NUTRIENT
CREDIT PURCHASE. THE BIOFILTER's PREVIOUSLY APPROVED DETENTION CELL HAS ALSO BEEN
RECONFIGURED WITH THIS AMENDMENT AND NOW MORE CLOSELY MIMICS THE APPROVED /
ASBUILT EROSION & SEDIMENT CONTROL BASIN. UTILIZING THE OUTLET STRUCTURES AND THE
MAJORITY OF THE ASBUILT GRADING WILL MINIMIZE ADDITIONAL DISTURBANCES. THE
DETENTION BASIN WILL CONTINUE TO PROVIDE WATER QUANTITY TREATMENT.
s,
e Peas RidyeRo
CXY Lnu,cN A.
`Q Cha rp ��Williarry0
o�
a' o
.echnmd
LicanMe
Mcsm..
fill
B
dohn`N yVameSpaM:. O
000
O
VICINITY MAP
SCALE: 1" = 500'
A
I SCOTThR. CbLLINSZ
ea"4"N4j L� Lic. No. 035791�
VV4 05/31/21 ,0J
ANomotive
aaeir A..,.mn
�n9 �l��am 9r
4'Osbya Reach
ROADS
LEGEND
EXISTING CULVERT
—...—...—
EARTH DITCH
0
O
CULVERT
DRIVEWAY CULVERT
Q
DROP INLET & STRUCTURE NO.
BENCH MARK
+
CURB
_ _ _ _ _
CLEARING LIMITS
0
CURB & GUTTER
MOT STANDARD STOP SIGN
PROPOSED PAVEMENT
2°°
EXIS77NG CONTOUR
PROPOSED PERM PAVERS
PROPOSED CONTOUR
EC-3A DITCH
240.55
PROPOSED SPOT ELEVA77ON
6.
DEPTH OF EC-JA DITCH
J
Z d
w a
J � Q
0 0
O
rrww U
V/ f a Z
m 2:z
z(f)
J K w
Lu0
O
w
LU Co
En
`H En
00 Of '
ti ti fV
M N \
N M
N W l 1
z
W
W
NA
F-
ul
z
ti
CM
M
N
co
i
N
O
N
N
a
LJJ
J
_J
L LI
F_
0
J
Q
U
i
Y
_F_
D
L L1
LLI
alf
F_
Q
O
O
N
z
LLI
G
0
Lu
G
Lf)
0
0
LL
Lu
0
LL
0
z
Lu
0
JOB NO.
122071
SCALE
AS NOTED
SHEET NO.
1
POST -DEVELOPMENT SCENARIO & BEST MANAGEMENT PRACTICE PRESERVATION EASEME T APPROVED Tc= 0.18 hrs. 0 MANAGED SLOPES
STORMWATER MANAGEMENT NARRATIVE: I I I ■���������J . 100' OF OLF W/ A ELEV.=3.5 (Tc=0.18 hrs.) PRESERVED SLOPES H
THE PROPOSED PLAN PROVIDES STORMWATER TREATMENT FOR THE CONSTRUCTION OF I ��• �.— _ _ R 87' OF CF W/ A ELEV.=5 (Tc > 0.01 hrs.)DUNLORA LOTS 1-29 (UNDER SEPARATE VSMP PLAN ADHEES TO PART IIB l
STREAM BUFFER
REQUIREMENTS FOR STORMWATER MA AGE E)NT. TIHE SUBMITTAL PACKAGE DOCUMENTS - 1 \ •• \� •��. 1 4,75 OE CF @ 14 ft/S (Tc > 0.01 hrs.)
ASSOCIATED WITH THIS PLAN SHOW WATER QUALITY COMPLIANCE BEING \ �� I \ O SCOTT R. LLINSZ
THE BEST MANAGEMENT PRACTICE OF OPEN SPACE PRESERVATION, AND 1 LPL]]]]
NUTRIENT CREDIT PURCHASE. THIS PLAN ALSO COMPLIES WITH PART IIB R — — — �• \ / ♦ I I I U Lie. No. 035791,E
I 1� \I �_ A — ) I (
THE ATTENUATION OF FLOWS IN THE DETENTION BASIN. PLEASE SEE THE ATTACHED I . —. � — I I � APPROVED 0 05/31/21
STORMWATER MANAGEMENT CALCULATIONS PACKET FOR THE FULL DETAILS OF PLAN J —� t I \ LIMITS OF TREE "�'p�
COMPLIANCE. I I I \ ♦ \\-.— — _s — — —i ♦ / J \ \ \ \\ II 1\ I ` \CLE�ARII G (TYP.) �SSIoxAL E��l�
Watershed Summary 3 I ; I ♦♦yam \�\ t I / _
APPROVED Pre -Development
Area, 1-year 2-year 10-yea
CN ac. r /—\•,�.1 J\ \\I —ifs
DAW 62 4.17 2.41 2.88 7.70
\
VARICK STREET, MARIN COURT, AND THE
APPROVED Post -Development ♦ _ \ \\ ` ♦j♦ 1 \\ ( I I \ \ \ \ \ \� \�\\\ \ \ \ SURROUNDING LOTS ARE NOT PART OF
Area, 1-year 2-year 10-year \ \ \� �� I \ I I \ \ \ \ \ \ \� \ \ THIS SET OF PLANS. THE PROPOSED SWM
CN \ y l ♦ \ \ \ \ \ / l \ \ \\\ \ FACILITIES & BEST MANAGEMENT
ac. Flow, cfs Flow, cfs Flow, cfs ♦1 \ \ \ \ \ \ \ \ \ \\\\ PRACTICES ARE PROPOSED WITH THIS
DAW 80 4.17 0.70 1.15 7.42 \\ \ �\ \ \\ \ \ / \ \ \ \ \\ \ \l \\\ \ >
SET OF PLANS & PROVIDE TREATMENT
�\\ \ r r FOR THE FUTURE ROADWAYS AND z a
AMENDED Post -Development w: \ \ / / \ \ \ \ \ 40� \ y \ \ \ \ \ \ \ \\ \ Lu
SURROUNDING LOTS. ¢
CN Area, 1-year 2-year 10-year w ? - \ \ \ \ / \/ / \\ \ `�`�� \ \ \ \ ♦1♦S \ \ \ \ \ \ \ \ \\ \ �,\\ \ \ \\s \ ` \ \ p o
<C/ \ \ \ \ \ \ \ \ \ \\ \ \� \ \ \ \
ac. Flow, cfs Flow, cfs Flow, cfs Ql / \ / / \ \\ `♦ \ \ \ \ \ \ Co �
DA'A' 80 4.17 0.66 1.12 7.17 — �\ \ �/� \ \ +C`\ \\ \ / \ \ \ \ \\ \ \\ \\\ \ \ \\ \\ \ v, � (n g
General Construction notes for Stormwater Management Plans av �_ \ \ - \ \ \ a
i. All dams and constructed fill to be within %of maximum dry density and 2%of 3 \ / \ \ `\ \ \ / 1 ♦ \ � \- � \\ •\ \ \ \ � O
optimum moisture content. All fill material to be approved by a geotechnical engineer. A O ♦-: „. / - \\\\\\\ / \ \ \ \ \ - �� \- \ - X �\ \ / \ \. - \ l `\ '� \\ \� \ \ ~ •• N
geotechnical engineer is to be present during construction of dams. V .� / \ �� �- -\, - \ \ \ \\ / r -
z. Pipe and riserjoints are to be watertight within stormwater Management facilities. _ ♦ _ \ A\AnA \\
3. For temporary sediment traps or basins which are to be converted to permanent J /� ♦ / ` - \. OVED D/-\ �y� \\/ - \\ \ / \ \ I\\ \ \ \ \
stormwater management facilities; conversion is not to take place until the site is Q 3 / / :\ \ \ \ \ ` - \ \ \ - \ 'rj,.\�j - \ \ \ \ I I % I \ \\ \ \ \ \ Lu
Lu
stabilized, and permission has been obtained from the County erosion control inspector. / / - \ \ \ 4-:L1_( �.\ \ - \ ° \ ♦ \ \ \ I \ I \ \
LU
Total Onsite Impervious Areas (Water Quality) / / ' / ♦ \ \ _ \ \ \ \ \\ l \\\ \ \ Ce
Roadway 29,600 sf 3 /; \ \ \\\ TC=a. S it rB. \ ` \ 3 \� \ \�♦\ \ \ \ \\_ \ \\ \ \ \
Sidewalks & Driveways 22110 sf ; / / / ♦ \ \ \ \\\\
Buildings 65700 sf / / — _ \ \ \ I \ \ ♦♦ \ \ I \ \ \ \ \ \ \
Total = 117,410 sf / / / / —\ \ r \ I \ \ \ ♦♦\ \ 1 \ \ \
D.A.'A' Post -Development Impervious Areas (Water Quantity) // / / / / ♦♦ \ \ \ \\ \\ \ / ,` l \I \ \ \ \ \ 1 I 1 \ \ \ \ \\\\ \FOORE§T & OPEN SPACE
Roadway 29,600 sf / / / / / \ ` \ \ \ \� / �- / \� \\ — \ \ "►♦1 1 \ \ \ I 1 1 \MitNf(DB 04967, PG
Sidewalks & Driveways 19300 sf 5 / / / / / / / / ♦ \ \ \ j �� / \ _C \ ♦ \ —� 1_ 1 1 \ \ `� 133r�3 ). E SSE ENT IS A BEST
Buildings 46650 sf / c / / / / / \ — _ ♦♦ \ \ / — 1 — 1 \ \ I 1 \ N MEN PRACTICE & N
Total = 95ss0 sf /" / / / \ \ \ \ \ \\� \ / \ s \ / \ \ 1 1 1 1 \ \ 1 I 1 I v� I�� �R
I / / / I \ IBI S FUTURE N m
'�\ 1 I \ b LO MENT&
\ \ \ 5 R�
B NCES
` '�i I/ � � �. l lS I I I I /_ �� �\ \ \ � — �P� \'� ! \ \ I I 1 1�♦i\ \ \\\ \`�\ \IIE�\ \®\\ \
I / \ \ \ •\� \ `� / � \ / J X ♦ \
� S r M 4UFF�R (TYP.)
/ l / ! \ \\v v v� y �� --��; A\ ® \ !� v yv A ♦iA \ V A \Vyw� A v v�v L
-- \
� \ \ cYi
/ / / I \\\ \ \ \ \ \ \ \ \ —/ /s I / \ \ \\\ \ \ �•tl \ \ \\ Z rn
LU
O L L]
\ � N
I I I I � ' ''�, I I v y✓/ v .i � INSTALL A V�sHAP�D w
>
\ \LU
\ I \ \ \� \ \ 1` \ ✓ - - < RIPRAP LIN�D CHANNW \ \ LU Uj 0
DIRECTING RUNOFFYNTt e \ \ Q J
M C
Z
THE SWFACILITY' UO
�i _iiyii ur�� i
V _ a O
—� LU
_W L9 _j U) O Q
LLJ
\ \ APPIROVEDISLC.PES HAVE__ —SWM FACILITY EASEMENT Q �
3 \ \ \DE1 ER�VII ED �O BE LESS THAN 250/0— \ \ \ `\\ \ `,. \ \ \ \ / % �- — / ( 49 7, — r,
DB o 6 PG i33 i34) I �n, ' O W
\ ( \ \ BA E O NEW TOPOGRAPHfE€XELIBIT & \ \ \ \\ \ \ \ -- — — / / J / i Y U'
UR EY PROVIDED-BY-ROUDABUSH,\\ \ \ \ \ \ \ \ \ \ /� \ 1� _ /\ _ �/ iTt- W J Q
\GA E P Nd ASS IATES AS PIERMtT-TED \ \ \\ \ \ \ \ \ \ �♦ — — —/ — — / / - H z
\ IUNDEI2SEtCTlON3:Jr4fb)�TYPICAL)\ \ \� \ \\\ \ \ \\\\ \ \\ \\ >�/ \ _ / \\ // j P' w
EXISTING MANAGED
rl
Ul
U)
SLOPES (TYP.)
LULU
LU i-
\ VA v \ _ _ — _— — — — — � Q
EXISTING PRESERVED \ \\ \ _ _/ — ■�■ ■I — �
STEEP SLOPES (TYP.) V \\ v / — _ — ----- __
O cC
_7I \ W o
ZD
\ v v --_ ------ -- _ Q C)
( \ v v v v vvy --- -- - ♦ / - - O
1� \ \\ \\, "\ _ in`iir-�_ii _ii_iii �T� — llffl l ttl=Nil :♦♦ // \ o W APPROVED STREAM W
m
BUFFER (TYP.)
\ GRAPHIC SCALE - _ �\ - — — — — —_ -- — �, JOB NO.
/ \ 30 0 15 30 60 120 \ _\ - - \ 122071
\ ( SWM FOREST & OPEN SPACE-)\ T _ — — -- - s SCALE
\ \ EASEMENT (DB 04967, PG i i 4 \ \ \
\ 33 3 — _ — s 1"=30'
( IN FEET) COINCIDES WITH PROPERTY LIN_ \ \ \ �\ — g
— 1 inch — 30 ft. ( \ \ \ \ \\• -
AMENDED SWM FACILITY TO TREAT= �\--
\ _ \ IST G EV D \ SHEET NO.
WATER QUANTITY (NOT QUALITY . STEEP SLOPE (TYP.)\
i
BASIN NOTES:
i. STATE APPROVED TRASH RACKS SHALL BE INSTALLED ON ALL ORIFICE OPENINGS.
2. A CONCRETE FOUNDATION SHALL BE INSTALLED ON THE RISER AS SHOWN & MEETING THE MINIMUM SPECIFICATIONS SET FORTH IN THE VESCH SPEC. #3.14.
3. CONTRACTOR AND CONSTRUCTION SHALL ADHERE TO ALL OSHA REQUIREMENTS. ADDITIONALLY, SPECIAL ATTENTION SHALL BE GIVEN TO THE CONSTRUCTION
BASIN's CONVERSION TO A PERMANENT SWM FACILITY. CONTRACTOR SHALL ENSURE THE PERMANENT SWM FACILITY HAS A STABILIZED GROUNDCOVER, SUCH AS
435 435
CONTRACTOR SHALL MAKE THE FOLLOWING MODIFICATIONS TO THE RISER:
1. PLUG THE 04" ESC DEWATERING ORIFICE WATERTIGHT (INV.=4o6.83 AB)
2. DRILL ONE (i) NEW 03.5" LOW -FLOW SWM ORIFICE (INV: 402.00)
3. DRILL FOUR (4) NEW 012" MID -FLOW SWM ORIFICES (INV.=4o8.25)
4. INSTALL A WEIR PLATE OVER THE TOP HALF OF THE BARREL'S OPENING
5. INSTALL TRASHRACKS ON THE LOW -AND MID -FLOW ORIFICES. SEE DETAIL
430
ON THIS SHEET, OR EQUIVALENT.
430
\�_JLOTGR
APPRO
ED
ORIGIN
LEXISTI
GGRAD
DING
(PRE-C
NSTRUC
ION)
425
425
420
-7
420
ASBUILT
STIR. 2A
TOP OF VIALL=424.24
PPROV
D0 8
L. III RCP
10=421.6
(i5" HD
E)
STANDPI
E W/TRASHRACKS
SHALL
SERVE A
THE RISER
STRUCTURE.
ASBUILT
048" PIS
R RIM
D -
L
72'
Q z= 8.
7 CF
ELEV.=4
9-7O'-
415
V=4.8FP
415
RIP
s
AP
Q0 If.13
1
C
$
\
ASB
ILT34'
IDE GRASS
LINED
LE
Dlo 0
91 FT
EME
GENCY
PILLWA
CREST
ELEVA
ION=410.
'
ASBUILT
GRAD
NG WITH
- "
(8'T
POF CIA
0 ELEV.=412.Oo')
PROPOSED
RACE
CON
RACTOR
SHALLI
STALLA
410
M
DIFICATONS
PRO
SEDV-
HAPEDV
OTCL.I
4 10
RIPR
P-LINED
ITCH 2.'STONE
DE
TH) WIT
FILTER
ABRIC
X
UN
ERLAYM
NTTOC
NVEY
Q
RUN
FFTOT
ESWM
ACILITY
APPROVE
TEMPO
ARY ESC
^'
SIN TO BE
CONVERI
ED INTO
PERMAN
NT SWM
AGILITY
405
PROVIDI
G STOR
ATER
\
405
UAN
ITY TREAT
ENT
APPROVED
FLOOR
GRADE E
EV.=402
00'. CON
RACTOR
ENSUR-POSITIVE
SLOPE
0THE RI
ERATA
LTIMES.
TD
4O0
400
CONNE
TIONSH
LLBEFI
MLYEM
EDDED
"INTOA
R
INFORCE
18" THICK
CONCF
ETE FOU
4DATION
THAT IS
' x
ND IS BURIED
BELOW
THE
LIMITS OF
THE BAS
N GRADING.
ASBUILT
15"RCP
ARREL
S-1-40940
395
1
=400.90',
INV. OU
=I3 9 90')
395
APPROVED
DOT EC-1
CLASS Al
UTLET PR
TECTION
W/ GE
TEXTILE qILTER
FAB
IC UNDER
AYMENT.
392
ASBUILT
DIMENSI
S: L=16.5,
WS=7.4',
W2=18.9'
392
WW
L!1
rl
0 N
N v1
W
lrl
IN
CO
J J
MtIt
1717
d
It
.t
w u_
PROFILE SCALES
11+00 11+50 12+00 12+50 13+00 13+50 13+75
DETENTION BASIN CONSTRUCTION NOTES:
FACILITY PLANTING SPECIFICATIONS:
1. THE DETENTION BASIN SHALL HAVE TURF GROUND COVER, SUCH AS GRASS OR SOME OTHER FORM OF A VEGETATIVE
GROUNDCOVER. LANDSCAPING BEYOND THIS IS OPTIONALAND IS NOT REQUIRED.
2. THE PROPOSED SIDE SLOPES OF THE BASIN SHALL BE A MAXIMUM OF 2:1 TO REDUCE THE RISK OF EROSION. THE PROPOSED
FLOOR SLOPES SHALL BE GRADED TO PROVIDE POSITIVE DRAINAGE AT ALL TI MES TO THE RISER STRUCTURE.
3. WOODY VEGETATION SHALL NOT BE PLANTED OR ALLOWED TO GROW WITHIN 15 FEET OF THETOE OFTHE EMBANKMENT NC
WITHIN 25 FEET OF THE PRINCIPAL SPILLWAY STRUCTURE.
4. A VEGETATED BUFFER SHALL BE PROVIDED THAT EXTENDS AT LEAST 25 FEETOUTWARD FROM THE BASIN TOP OF DAM
ELEVATION. PERMANENT STRUCTURES (E.G., BUILDINGS, SHEDS, etc.) SHOULD NOT BE CONSTRUCTED WITHIN THE BUFFER AR
EXISTING TREES SHALL BE PRESERVED IN THE BUFFER AREA DURING CONSTRUCTION IF AT ALL POSSIBLE.
S. THE SOILS IN THE STORMWATER BUFFER AREAARE OFTEN SEVERELY COMPACTED DURING THE CONSTRUCTION PROCESS, TO
ENSURE STABILITY THE DENSITY OF THESE COMPACTED SOILS CAN BE SO GREATTHAT IT EFFECTIVELY PREVENTS ROOT
PENETRATION AND, THEREFORE, MAY LEAD TO PREMATURE MORTALITY OR LOSS OF VIGOR. AS A RULE OF THUMB, PLANTING
HOLES SHOULD BE THREE TIMES DEEPER AND WIDER THAN THE DIAMETER OF THE ROOTBALL FOR BALL -AND -BURLAP STOCK,
AND FIVE TIMES DEEPER AND WIDER FOR CONTAINER -GROWN STOCK.
6. AVOID SPECIES THAT REQUIRE FULL SHADE, OR ARE PRONE TO WIND DAMAGE. EXTRA MULCHING AROUND THE BASE OF TREE
AND SHRUBS IS STRONGLY RECOMMENDED ASA MEANS OF CONSERVING MOISTURE AND SUPPRESSING WEEDS.
1. THE CONTRACTOR SHALL BE RESPONSIBLE FOR LAYOUT OF ALL WORK COVERED UNDER THESE PLANS.
2. LANDSCAPE CONTRACTOR SHALL REFER TO THE STANDARDIZED LANDSCAPE SPECIFICATIONS FOR THE STATE OF VIRGINIA FOR
ADDITIONAL INFORMATION. THE CONTRACTOR SHALL ABIDE BY ITS CONTENTS; HOWEVER ANY NOTES OR SPECIFICATIONS ON '
THE PLANS SHALL SUPERSEDE THOSE OUTLINED IN THE SPECIFICATIONS MANUAL (COPIES ARE AVAILABLE FOR A FEE FROM THE'
VIRGINIA CHAPTER OF THE AMERICAN SOCIETY OF LANDSCAPE ARCHITECTS, VIRGINIA NURSERYMEN'S ASSOCIATION, INC. AND
THE VIRGINIA SOCIETY OF LANDSCAPE DESIGNERS).
3. ALL PLANT MATERIAL SHALL MEETTHE MINIMUM SPECIFICATIONS AND STANDARDS DESCRIBED IN THE CURRENT ISSUE OF THE,
AMERICAN STANDARD FOR NURSERY STOCK, PUBLISHED BY THE AMERICAN ASSOCIATION OF NURSERYMEN, 1250 STREET, NW,
SUITE 500, WASHINGTON, DC 20005.
4. THE CONTRACTOR SHALL VERIFY ALL DIMENSIONS IN THE FIELD AND NOTIFY THE DESIGNER OF ANY VARIANCE FROM THE PLAN,
S. THE LANDSCAPE CONTRACTOR IS RESPONSIBLE FOR VERIFYING THE LOCATION OF ANY ONSITE UTILITIES (CALL MISS UTILITY
1-800-552-7001 BEFORE ANY EXCAVATION).
6. REFER TO THE APPROVED FINAL SITE PLANS FOR ANY DETAILED SITE INFORMATION.
7. ALL WORK SHALL BE COORDINATED WITH OTHER PARTIES.
8. PLANTS WILL BE PREPARED FOR SHIPMENT IN A MANNER THAT WILL NOT CAUSE DAMAGE TO THE BARK, BUDS, BRANCHES,
STEMS, OR OVERALL SHAPE OF THE STOCK. CONTAINER GROWN PLANTS WILL BE TRANSPORTED IN THE CONTAINERS IN WHICH
THEY HAVE GROWN.
9. ALL PLANT MATERIAL, UNLESS OTHERWISE SPECIFIED, SHALL BE UNIFORMLY BRANCHED AND HAVE A VIGOROUS ROOT SYSTEM.
PLANT MATERIAL SHALL BE HEALTHY, VIGOROUS, AND FREE FROM DEFECTS, DECAY, DISEASES, INSECT PEST EGGS, AND ALL
FORMS OF INFESTATION. ALL PLANT MATERIAL SHALL BE FRESH, FREE FROM TRANSPLANT SHOCK OR VISIBLE WILT. PLANTS
DEEMED UNHEALTHY WILL BE REJECTED.
10. ALL CONTAINER STOCK SHALL HAVE BEEN PROPAGATED IN A CONTAINER LONG ENOUGH FOR THE ROOT SYSTEM TO HAVE
DEVELOPED SUFFICIENTLY TO HOLD ITS SOIL. CONTAINER STOCK WITH POORLY DEVELOPED ROOT SYSTEMS WILL NOT BE
ACCEPTED.
11. PLANTS NOT INSTALLED ON THE DAY OF ARRIVAL ON SITE SHALL BE STORED AND PROTECTED BY THE CONTAINER. OUTSIDE
STORAGE AREAS WILL BE SHADED AND PROTECTED FROM THE WIND AND SUN. PLANTS STORED ON SITE SHALL BE PROTECTED
FROM ANY DRYING AT ALL TIMES BY COVERING THE BALLS OR ROOTS WITH MOIST SAWDUST, WET BURLAP, WOOD CHIPS,
SHREDDED BARK, PEAT MOSS, OR OTHER SIMILAR MULCHING MATERIAL.
12. THE OWNER RESERVES THE RIGHT TO SUBSTITUTE PLANT MATERIAL TYPE, SIZE AND/OR QUANTITY. ANY SUBSTITUTIONS MUST
BE APPROVED BY THE INSPECTOR INITIALLY, AND THEN THE DESIGNER.
13. MINOR FIELD ADJUSTMENTS MAY BE NECESSARY DUE TO SITE CONDITIONS (EX: FOOTBALL AND UTILITY CONFLICT). MAJOR
ADJUSTMENTS MUST BE APPROVED BY THE DESIGNER.
14. NO PLANTING SHALL OCCUR WHEN THE SOIL IS FROZEN.
15. PLANT MATERIAL SHALL BE PLACED IN EXISTING SOIL WITH EACH PLANTING PIT EXCAVATED TO A SIZE SUFFICIENT TO CONTAIN
THE ENTIRE ROOT BALL OR ROOT MASS, WITHOUT CRAMPING ROOT STOCK.
16. THE CONTRACTOR SHALL MAINTAIN A ONE (1) CALENDAR YEAR 90% CARE AND REPLACEMENT WARRANTY FOR ALL PLANTINGS.
THE PERIOD OF CARE AND REPLACEMENT SHALL BEGIN AFTER INSPECTION AND APPROVAL OF THE COMPLETE INSTALLATION OI
ALL PLANTS AND CONTINUE FOR ONE CALENDAR YEAR.
17. THE CONTRACTOR IS RESPONSIBLE FOR REMOVAL AND DISPOSAL OF TRASH AND DEBRIS WITHIN THE LIMITS OF THE PLANTING
ON A DAILY BASIS.
18. THE CONTRACTOR WILL NOT BE RESPONSIBLE FOR PLANT MATERIAL THAT HAS BEEN DAMAGED BY VANDALISM, FIRE, OR OTHEI
ACTIVITIES BEYOND THE CONTRACTOR's CONTROL.
FACILITY CONSTRUCTION
1. THE DETENTION BASIN MAY SERVE AS A SEDIMENT BASIN AND/OR TRAP DURING PROJECT CONSTRUCTION. IF THIS IS DONE, TH
VOLUME SHALL BE BASED ON THE MORE STRINGENT SIZING RULE (EROSION AND SEDIMENT CONTROL REQUIREMENTS VS.
STORMWATER TREATMENT REQUIREMENTS). INSTALLATION OF THE PERMANENT RISER SHALL BE INITIATED DURING THE
CONSTRUCTION PHASE, AND DESIGN ELEVATIONS SHALL BE SET WITH FINAL CLEANOUT OF THE SEDIMENT BASIN AND
CONVERSION TO THE POST -CONSTRUCTION POND IN MIND. APPROPRIATE PROCEDURES SHALL BE IMPLEMENTED TO PREVENT
DISCHARGE OF TURBULENT WATERS WHEN THE BASIN IS BEING CONVERTED INTO AN DETENTION BASIN.
2. THE DETENTION BASIN SHALL ONLY BE CONSTRUCTED AFTER THE CONTRIBUTING DRAINAGE AREA TO THE POND IS COMPLETEL
STABILIZED. IF THE PROPOSED POND SITE WILL BE USED AS A SEDIMENTTRAP OR BASIN DURING THE CONSTRUCTION PHASE,
THEN THE FACILITY WILL BE DEWATERED, DREDGED AND RE -GRADED TO DESIGN DIMENSIONS AFTER THE ORIGINAL SITE
CONSTRUCTION IS COMPLETE.
T T R T R 3. INSTALL E&S CONTROLS PRIOR O CONSTRUCTION OF HE BASIN INCLUDING TEMPORARY DE WA E ING DEVICES AND
STORMWATER DIVERSION PRACTICES. ALL AREAS SURROUNDING THE BASIN THAT ARE GRADED OR DENUDED DURING
CONSTRUCTION SHALL BE PLANTED WITH TURF GRASS, NATIVE PLANTINGS, OR OTHER APPROVED METHODS OF SOIL
STABILIZATION.
4. CONTRACTOR SHALL EXCAVATE THE CORE TRENCH AND INSTALL THE SPILLWAY PIPE DURING THE ESC PHASE.
S. CONTRACTOR SHALL ALSO INSTALL THE RISER, OUTFLOW STRUCTURE AND/OR THE BARREL(s) DURING THE ESC PHASE TO ENSUI
THE TOP INVERT OF THE OVERFLOW WEIR IS CONSTRUCTED LEVEL AT THE DESIGN ELEVATION.
6. THE CONTRACTOR SHALL THEN CONSTRUCTTHE IMPERVIOUS CLAY CORE EMBANKMENT AND ANY INTERNAL BERMS IN 8TO
12-INCH UFTS AND COMPACT THE LIFTS WITH APPROPRIATE EQUIPMENT.
7. UPON COMPLETION OF THE EMBANKMENT GRADING, THE CONTRACTOR SHALL EXCAVATE/GRADE UNTIL THE APPROPRIATE
ELEVATION AND DESIRED CONTOURS ARE ACHIEVED FOR THE BOTTOM AND SIDE SLOPES OF THE BASIN.
8. CONTRACTOR SHALL THEN CONSTRUCT THE EMERGENCY SPILLWAY IN CUT OR STRUCTURALLY STABILIZED SOILS.
9. THE CONTRACTOR SHALL THEN FINISH CONSTRUCTION OF ALL OUTLET STRUCTURES, INCLUDING DOWNSTREAM RIP -RAP APROI
PROTECTION.
10. THE CONTRACTOR SHALL NEXT STABILIZE EXPOSED SOILS BY HYDROSEEDING OR SEEDING OVER STRAW.
11. THE CONTRACTOR SHALLTHEN INSTALLTHE APPROPRIATE BASIN LANDSCAPING IN ACCORDANCE WITH THE APPROVED PLANS.
FACILITY MAINTENANCE:
MAINTENANCE OF THE DETENTION BASIN IS DRIVEN BY ANNUAL INSPECTIONS THAT EVALUATE THE CONDITION AND PERFORMANCE
OF THE FACILITIES. DURING THESE INSPECTIONS THE FOLLOWING TASKS SHALL BE PERFORMED BY THE CONTRACTOR IN THE FIRST
YEAR FOLLOWING INSTALLATION, AND THE OWNER THEREAFTER:
1. MEASURE SEDIMENT ACCUMULATION LEVELS IN THE BASIN.
2. MONITOR THE GROWTH OF THE GROUNDCOVER AND ANY TREES AND SHRUBSPLANTED, AS APPLICABLE. RECORD THE SPECIES
AND THEIR APPROXIMATE COVERAGE, AND NOTE THE PRESENCE OF ANY INVASIVE PLANT SPECIES, AS APPLICABLE.
3. INSPECT THE CONDITION OF STORMWATER INLETS TO THE BASIN FOR MATERIAL DAMAGE, EROSION OR UNDERCUTTING.
4. INSPECT THE FLANKS OF UPSTREAM AND DOWNSTREAM CHANNELS FOR EVIDENCE OF SLOUGHING, ANIMAL BURROWS, BOGGY
AREAS, WOODY GROWTH, OR GULLY EROSION THAT MAY UNDERMINE EMBANKMENT INTEGRITY.
5. INSPECT BASIN OUTFALL CHANNEL FOR EROSION, UNDERCUTTING, RIP -RAP DISPLACEMENT, WOODY GROWTH, etc.
6. INSPECT CONDITION OF PRINCIPAL SPILLWAY AND RISER FOR EVIDENCE OF SPALLING, JOINT FAILURE, LEAKAGE, CORROSION OR
OTHER FAILURES.
7. INSPECT CONDITION OF ALL TRASH RACKS, REVERSE SLOPED PIPES OR FLASHBOARD RISERS FOR EVIDENCE OF CLOGGING,
LEAKAGE, DEBRIS ACCUMULATION OR OTHER FAILURES AS APPLICABLE.
8. INSPECT MAINTENANCE ACCESS TO ENSURE IT IS FREE OF WOODY VEGETATION, AND CHECK TO SEE WHETHER VALVES,
MANHOLES AND LOCKS CAN BE OPENED AND OPERATED.
9. INSPECT INTERNAL AND EXTERNAL SIDE SLOPES OF THE BASIN FOR EVIDENCE OF SPARSE VEGETATIVE COVER, EROSION, OR
SLUMPING.
10. OWNER OR CONTRACTOR SHALL MAKE NEEDED REPAIRS IMMEDIATELY.
FACILITY INSPECTION:
MULTIPLE INSPECTIONS ARE CRITICAL TO ENSURE THE BASIN(s) ARE PROPERLY CONSTRUCTED. BECAUSE THE TIMING OF THE
INSTALLATION IS DICTATED BY THE CONTRACTOR, THE CONTRACTOR SHALL BE RESPONSIBLE FOR CONTACTING THE ENGINEER AND
INSPECTOR PRIOR TO INSTALLATION. MULTIPLE SITE VISITS AND INSPECTIONS ARE REQUIRED TO BE SCHEDULED BY THE CONTRALTO
WITH THE ENGINEER AND INSPECTOR DURING THE FOLLOWING STAGES OF THE DETENTION BASIN's CONSTRUCTION PROCESS:
1. PRE -CONSTRUCTION MEETING
2. INITIAL SITE PREPARATION (INCLUDING INSTALLATION OF PROJECT E&S CONTROLS)
3. EXCAVATION/GRADING (e.g., INTERIM/FINAL ELEVATIONS)
4. EXTENDED DETENTION BASIN INSTALLATION (e.g., INTERIM AND FINAL ELEVATIONS)
S. INSTALLATION OF THE EMBANKMENT, THE RISER/PRIMARY SPILLWAY, AND THE OUTLET STRUCTURE(s).
6. PLANTING PHASE (WITH AN EXPERIENCED LANDSCAPE ARCHITECT PRESENT/DIRECTING)
7. FINAL INSPECTION (DEVELOP A PUNCH LIST FOR FACILITY ACCEPTANCE) L
EMBANKMENT NOTES:
THE EMBANKMENT SHALL HAVE A COMPACTED CLAY CORE WITH A CUTOFF TRENCH & BE IN ACCORDANCE
WITH THE DETAILS SHOWN ON THIS SHEET. BERMS AND SPILLWAYS SHALL BE STABILIZED WITH EC-3 MATTING
& THE REMAINING DISTURBED SLOPES SHALL BE STABILIZED WITH EC-2 MATTING. ALL BERM FILL MATERIAL
SHALL CONSIST OF ML, CL, SC OR GC SOILS & BE FREE OF WOOD, ROOTS, ROCKS OR ANY OTHER NON
COMPACTING SOIL. COMPACTED FILLSHALL BE PROCTOR MAXIMUM DRY DENSITY ASTM D698 AND HAVE A
MINIMUM OF 9S%OF MAXIMUM DRY DENSITY AND 2%OF OPTIMUM MOISTURE CONTENT. ALL FILL
MATERIAL AND CONSTRUCTION SHALL BE APPROVED BYAN ONSITE GEOTECHNICAL ENGINEER PRESENT
DURING THE CONSTRUCTION OF THE EMBANKMENTS AND FILL AREAS,
e
1/2" zinc plated hook
attached with 3/8"
fasten-.
Isometric
". vft e� e
s
5/8- did hole
WE
1 /8" din. holes
III structural plastic with
2-1/8" holes end 1/4" plate
annu:nctured by 21ns-ac
9oluti6na Inc. or equal
on*" ■'itb optional plate
HDPE structural plastic with
2-1/8" holes and 114' plate
.�.'-L'Ction / manufactured by Plastic
Solutions Inc- or equal
0 L 0
O // C) X\ o
single BI I',ICViItio rl
aririce
DFRRIS CAGE
STEEL WEIR PLATE TO BE -
FASTENED OVER THE 1S"
OUTLET OPENING,
COVERING THE TOP HALF OF
THE OUTLET OPENING.
SEAL OPENINGS AROUND
THE PLATE WITH MORTAR
TO CREATE A WATER -TIGHT
PLATE OVER THE OPENING.
INSTALL STEPS IN EX. RISEF
STRUCTURE IF THE STEPS
HAVE NOT PREVIOUSLY
BEEN INSTALLED. '
48" RISER
OUTLET PIPE
15" RCP ,
WEIR PLATE DETAIL
N.T.S.
PLASTIC
SOLUTIONS
INC.
P.O. Box A386
Winchester it 22604
877-877-5727
.n.pladic-wlwurnii.
SECTION A-9: TYPICAL GRAPEIIC aI. DETAII.5
sr- Homogeneous fill
�
T ``'Cut off tmvi l4-4e below miWe
Soil or rock L - - - - - - material - - J
TYPICAL HOMOGENEOUS
EMBANKMENT
Transition fill
ock or gravel
173
Pipe Cutlet Coarse fi�tPr .
Perforated Collector arou 50
FaundDtJon drain Blonket drain
FOUNDATION DRAIN BLANKET DRAIN
drain
Send, graiiI Dr Loci.
drain a4Uiet
Rod( or 9ravel
Rock be a drain
A n [ D
�Transilion filter Transition Filter
CHIMNEY DRAIN TOE DRAIN
Sou/1ce� SCSEngineenng Field kfauua!
Figure A -la. Homogeneous Embankments w/Seepage Controls
Storrnll
ROUND SERIES TRASH RACK
CONCRETE MANHOLE
STANDARD 601 NCH RACK SHOWN
DIMENSIONS IN INCHES
PLAN
SIDE VIEW
StormRaXTM Round Series for Concrete Manhole
Tart Nl I
MA
1 Mal
DIRC
MI
MI
RSlI
ITJI
1/36
28
M
30
RS36
213'i
UI
4D,1
1 36
tl
RSY1
27K
1 IT
1 S4
45
1 S7
RS•w 1
27%
1 UTA
I "M
I A)
1 A
Plaii Solutions, IIK. astoliDt
W b.4a94. Vlerlaaler. VA 12LW
L3a M.fAee VC. VAnaran!r, VA 12EE6i
"9T77 e7T.s7n phone PRO[CT.
1T4MX 72zuro,.,,
h.q,V7www.paa.sewam.mn
u...w IIIT
iunara c
CONCRETE STRUCTURE DIMlMBONa
INSIDE STRUCTURE DIMENSION
OUTRIDE STRUCTURE DIMENSION
AVAILABLE oFnI
CROSS BRACING FOR OVERHAND
HDPE ANTI -VORTEX RATE
DATE
DR4WNn
wpoer
DEAL
r-�
Lic. No. 035791,'D
>_ 05/31/21 J
J
to ce
z a
w Q
k O tr
O
U
U/ CO a Z
CO 2:z
In
ZW J � w
O w O
C.
H z w
U)
LL1 Co
� Co
'■■P
00 Ch N
M N \
'H N M
N W N
0
Z
ff
W
W
Z
L9
Z
Ul
Z
J
J
U
VJ
ti
M
M
N
M
I
N
C:)
N
N
LU
J
J
CO
LU
0
J
Q
U
I
LU
LU
LU
VJ
olf
LU
C:)
C]
N
M
LU
W
/Q
LL
V
0
0
/
LL
LU
I..L
0
z
ZD
0
J
H1
W
0
06
LLJ
0
z
W
W
z
LU
Of
G
0
JOB NO.
122071
SCALE
AS SHOWN
III=5' M
1"=5o'(H)
BASIN 'A'
SHE°T NO.
9