HomeMy WebLinkAboutSW5220101_Plansheet (C9.01) - SCM Detail_20220804STORMWATER CONTROL MEASURE 'A' CONSTRUCTION SPECIFICATIONS
GENERAL NOTES
CONSTRUCTION SEQUENCE
1.
PRIOR TO CONSTRUCTION, ANY DISCREPANCIES IN THE PLANS AND NOTES SHALL BE BROUGHT TO THE DESIGN ENGINEER'S ATTENTION
1.
PRIOR TO CONSTRUCTION, THE OWNER SHALL OBTAIN A LAND DISTURBING (GRADING) PERMIT AND AN "APPROVAL TO CONSTRUCT"
IMMEDIATELY.
FROM THE NORTH CAROLINA DEPARTMENT OF ENVIRONEMNTAL QUALITY AND ALL OTHER NECESSARY PERMITS FROM APPLICABLE
AGENCIES (E.G. 404 / 401 PERMITS)
2.
THE PROJECT WILL MEET ALL OF THE REQUIREMENTS RELATIVE TO BEST MANAGEMENT PRACTICES AND ENGINEERED STORMWATER
CONTROL STRUCTURES AS OUTLINED IN NORTH CAROLINA STORMWATER CONTROL DESIGN MANUAL.
2.
INSTALL ALL SEDIMENT AND EROSION CONTROL MEASURES PER THE APPROVED SEDIMENT AND EROSION CONTROL PLAN. THE
CONTRACTOR SHALL MAINTAIN ALL APPROVED SEDIMENT AND EROSION CONTROL MEASURES THROUGHOUT THE ENTIRE PROJECT, AS
3.
THE FINAL CERTIFICATION FOR THIS FACILITY WILL INCLUDE A CERTIFICATION BY THE ON -SITE GEOTECHNICAL ENGINEER THAT THE
REQUIRED. THE CONTRACTOR SHALL RECEIVE APPROVAL FROM THE EROSION CONTROL INSPECTOR, AS REQUIRED BY GOVERNING
PROJECT WAS CONSTRUCTED PER THE APPROVED PLANS. IT IS THE RESPONSIBILITY OF THE CONTRACTOR TO COORDINATE WITH THE
AGENCIES, PRIOR TO ANY CLEARING.
ON -SITE GEOTECHNICAL ENGINEER FOR OBSERVATION AND TESTING SUCH THAT THE ON -SITE GEOTECHNICAL ENGINEER CAN CERTIFY THE
CONSTRUCTION OF THE DAM EMBANKMENT AND SPILLWAY. THIS CERTIFICATION MUST ADDRESS THE TESTING FOR MATERIALS AND
3.
CLEAR AND GRUB AREA WITHIN THE LIMITS OF THE PROPOSED DAM CONSTRUCTION. ALL TREES AND THEIR ENTIRE ROOT SYSTEMS MUST
COMPACTION OF THE DAM EMBANKMENT AND SPILLWAY.
BE REMOVED FROM THE DAM FOOTPRINT AREA AND BACKFILLED WITH SUITABLE SOIL MATERIAL. THE BACKFILLED AREAS SHALL BE
COMPACTED TO THE SAME STANDARDS AS THE DAM EMBANKMENT. THE REMAINING AREA OF THE EMBANKMENT SHALL BE STRIPPED TO
4.
ALL CONSTRUCTION ACTIVITY RELATED TO THE PROPOSED STORMWATER CONTROL MEASURE SHALL BE PER THE DETAILS AND
A SUITABLE DEPTH AS DIRECTED BY THE ON -SITE GEOTECHNICAL ENGINEER. ANY RESIDUAL SOILS TO BE LEFT IN PLACE MUST BE WELL
SPECIFICATIONS SHOWN IN THESE DRAWINGS. SOILS COMPACTION AND OTHER MISCELLANEOUS DETAILS AND SPECIFICATIONS MAY BE
SCARIFIED TO PROMOTE BONDING OF THE NEW EMBANKMENT FILL. NO EMBANKMENT MATERIAL SHALL BE PLACED FOR THE DAM OR
MODIFIED PER THE RECOMMENDATIONS OF THE ON -SITE GEOTECHNICAL ENGINEER. HOWEVER, PRIOR TO IMPLEMENTATION, THE DESIGN
KEY TRENCH UNTIL APPROVAL OF THE DAM SUBGRADE IS OBTAINED FROM THE ON -SITE GEOTECHNICAL ENGINEER.
ENGINEER SHALL BE NOTIFIED OF ANY DEVIATION FROM THESE DESIGN DRAWINGS, INCLUDING SHOP DRAWINGS FOR ANY PROPOSED
MODIFICATION.
4.
EXCAVATE FOR THE NEW KEY TRENCH ALONG THE CENTERLINE OF THE PROPOSED DAM EMBANKMENT. THE TRENCH SHALL EXTEND A
MINIMUM OF 5 FT BELOW EXISTING GRADE OR 2 FT BELOW THE 18"0 RCP OUTLET BARREL AND SHALL HAVE A MINIMUM BOTTOM
5.
DURING THE INITIAL STAGES OF CONSTRUCTION THE STORMWATER CONTROL MEASURE MAY BE USED AS A SEDIMENT BASIN FOR
WIDTH OF 5 FEET. THE KEY TRENCH SIDESLOPES SHALL BE A MINIMUM OF 1:1 (H:V). WHEN EXCAVATING THE KEY TRENCH, IF ANY DEBRIS
EROSION CONTROL PURPOSES. IF SO THE CONTRACTOR SHALL FOLLOW THE GENERAL CONSTRUCTION SEQUENCE BELOW:
IS ENCOUNTERED TO AN EXTENT THAT SUCH DEBRIS MAY EXIST IN OTHER INSITU PORTIONS OF THE DAM EMBANKMENT IT SHOULD ALSO
A. THE CONTRACTOR SHALL CONSTRUCT THE ENTIRE FACILITY PERMANENT OUTLET STRUCTURE DAM ETC. WITH THE EXCEPTION OF
( � )
BE REMOVED. THE KEY TRENCH SHALL BE COMPACTED TO THE SAME SPECIFICATION LISTED IN ITEM 4 OF THE SECTION TITLED "BERM
THE INTERIOR FINE GRADING FOR THE FACILITY. THE INTERIOR FINE GRADING WILL BE CONSTRUCTED ONCE THE EROSION CONTROL
AND SOIL COMPACTION SPECIFICATIONS." DEPENDING UPON ON -SITE SOIL CONDITIONS ENCOUNTERED DURING EXCAVATION, THE
PHASE IS COMPLETE.
ON -SITE GEOTECHNICAL ENGINEER MAY VARY THE DEPTH AND DIMENSIONS OF THE KEY TRENCH AS DEEMED NECESSARY. THE ON -SITE
B. THE TEMPORARY DRAW DOWN RISER (OR SKIMMER) SHALL BE CONNECTED TO THE PERMANENT 6"0 DIP DRAIN PIPE.
GEOTECHNICAL ENGINEER SHALL RETAIN DOCUMENTATION OF ANY VARIATION FOR FUTURE AS -BUILT SUBMITTALS TO THE TOWN OF
C. ONCE THE UPSTREAM DRAINAGE AREA IS STABILIZED AND THE EROSION CONTROL INSPECTOR APPROVES THE REMOVAL OF THE
BUNN.
SEDIMENT BASIN, THE CONTRACTOR SHALL REMOVE THE TEMPORARY DRAW DOWN RISER (OR SKIMMER) AND CLEAN OUT THE
BASIN. ALL SEDIMENT, TRASH, ETC. SHALL BE DISPOSED OF PROPERLY (I.E. - PLACED IN A LANDFILL) AND NOT STOCKPILED IN AN AREA
5.
BEGIN PLACEMENT OF BACKFILL WITHIN THE KEY TRENCH. THE KEY TRENCH SHALL BE COMPACTED TO THE SPECIFICATIONS LISTED ITEM 4
WHERE WATER QUALITY COULD BE ADVERSELY AFFECTED.
OF THE SECTION TITLED "BERM AND SOIL COMPACTION SPECIFICATIONS." THE KEY TRENCH SHALL BE TESTED PER THE SPECIFICATIONS
D. ONCE THE BASIN IS CLEANED OUT, AND ALL EROSION CONTROL DEVICES REMOVED, THE CONTRACTOR SHALL CONSTRUCT THE
LISTED IN THAT SECTION.
INTERIOR GRADING SHOWN ON THIS SHEET.
E. ONCE THE GRADING IS COMPLETE, THE CONTRACTOR SHALL REQUEST AN ON -SITE INSPECTION AND AN AS -BUILT SURVEY PRIOR TO
6.
PRIOR TO INSTALLATION, SUBGRADE CONDITIONS ALONG THE SPILLWAY PIPES SHOULD BE EVALUATED BY THE ON -SITE GEOTECHNICAL
INSTALLATION OF THE STORMWATER CONTROL MEASURE PLANTS. IF THE CONTRACTOR PLANTS THE PROPOSED VEGETATION PRIOR
ENGINEER TO ASSESS WHETHER SUITABLE BEARING CONDITIONS EXIST AT THE SUBGRADE LEVEL. SHOULD SOFT OR OTHERWISE
TO AN AS -BUILT SURVEY (AND SUBSEQUENT APPROVAL), ANY CHANGES TO THE GRADING / RE -PLANTING OF PLANTS WILL BE AT THE
UNSUITABLE CONDITIONS BE ENCOUNTERED ALONG THE PIPE ALIGNMENTS, THESE MATERIALS SHOULD BE UNDERCUT AS DIRECTED BY
CONTRACTOR'S EXPENSE.
THE GEOTECHNICAL ENGINEER. THE UNDERCUT MATERIALS SHALL BE REPLACED WITH ADEQUATELY COMPACTED STRUCTURAL FILL, LEAN
F. ONCE THE ENGINEER HAS APPROVED THE AS -BUILT GRADING, THE CONTRACTOR SHALL PLANT THE PROPOSED STORMWATER
CONCRETE OR FLOWABLE FILL AS DIRECTED BY THE ON -SITE GEOTECHNICAL ENGINEER.
CONTROL MEASURE PLANTS SHOWN ON THE LANDSCAPE PLAN FOR THE FACILITY. AFTER COMPLETION OF THE PLANTING, THE
LANDSCAPE CONTRACTOR SHALL PROVIDE A LETTER TO THE ENGINEER CERTIFYING THAT THE PLANTS HAVE BEEN INSTALLED PER THE
7.
IN ORDER TO HELP PROTECT THE SOIL SUBGRADE FROM DETERIORATION DUE TO EXPOSURE RAINFALL SEEPAGE AND RUNOFF BEFORE
( )
APPROVED STORMWATER CONTROL MEASURE PLANTING PLAN.
THE CRADLE CAN BE POURED, IT IS STRONGLY RECOMMENDED THAT A 3" TO 4" THICK CONCRETE MUD MAT BE POURED OVER THE
6.
ALL OSHA REQUIREMENTS FOR EXCAVATIONS (SHORING, DEPTH, ETC.) ARE THE RESPONSIBILITY OF THE CONTRACTOR. IF REQUIRED, THE
SUBGRADE ONCE IT IS APPROVED BY THE ON -SITE GEOTECHNICAL ENGINEER. THE MUD MAT WILL ALSO PROVIDE BEARING FOR THE
CONTRACTOR SHALL PROVIDE AN EXCAVATION PLAN TO BE SEALED BY A NC P.E. IT IS THE RESPONSIBILITY OF THE CONTRACTOR TO
BLOCKS THAT TEMPORARILY SUPPORT THE SPILLWAY PIPE UNTIL THE CRADLE CAN BE POURED. THE METHOD OF BLOCK SUPPORT FOR THE
DETERMINE IF AN EXCAVATION PLAN IS REQUIRED. THE JOHN R. MCADAMS COMPANY ASSUMES NO RESPONSIBILITY FOR ANY
PIPE PROPOSED BY THE CONTRACTOR SHOULD BE SUBMITTED TO THE JOHN R. McADAMS COMPANY FOR REVIEW.
EXCAVATION DESIGN RELATED TO SAFETY OR OSHA REQUIREMENTS.
8.
BEGIN CONSTRUCTION OF THE NEW EMBANKMENT. FILL MATERIALS SHALL BE PLACED IN MAXIMUM 8" THICK LIFTS PRIOR TO
7.
ON -SITE GEOTECHNICAL ENGINEER TO DETERMINE IF IN -SITU SOILS ENCOUNTERED WOULD MAINTAIN A STORMWATER CONTROL
COMPACTION, UNLESS DIRECTED OTHERWISE BY THE ON -SITE GEOTECHNICAL ENGINEER. FILL LIFTS SHALL BE CONTINUOUS OVER THE
MEASURE PERMANENT POOL AT DESIGN ELEVATION. IF HIGHLY PERMEABLE SOILS ARE ENCOUNTERED THAT WOULD NOT MAINTAIN
ENTIRE LENGTH OF FILL. IF IT IS NECESSARY, THE EMBANKMENT FILL MATERIAL WILL BE OVERBUILT IN HORIZONTAL LIFTS AND CUT BACK
THE PERMANENT POOL ELEVATION AS DESIGNED, A CLAY LINER MAY BE REQUIRED TO MAINTAIN A PERMANENT POOL OF WATER IN THE
TO FINAL GRADE IN ORDER TO ACHIEVE PROPER COMPACTION.
STORMWATER CONTROL MEASURE. FINAL DETERMINATION IF A CLAY LINER IS NEEDED SHALL BE THE RESPONSIBILITY OF THE ON -SITE
GEOTECHNICAL ENGINEER. UPON DETERMINATION OF HIGHLY PERMEABLE SOIL CONDITIONS, ON -SITE GEOTECHNICAL ENGINEER WILL
9.
AS CONSTRUCTION OF THE EMBANKMENT MOVES FORWARD, IT WILL BE NECESSARY TO INSTALL THE CONCRETE CRADLE. SEE NOTE ON
INFORM THE DESIGN ENGINEER AND RECOMMEND LINER SPECIFICATIONS.
CRADLE DETAIL (SHEET C9.03). THIS MAY BE CONSTRUCTED USING ONE OF THE FOLLOWING METHODS:
8.
IT IS ANTICIPATED THAT DEWATERING WILL BE NECESSARY IN THE EXCAVATION AREAS (E.G. - EMBANKMENT SUB GRADE, INTERIOR
A. IF THE PROPOSED STRUCTURAL FILL MATERIAL IS UTILIZED AS THE FORMWORK FOR THE CONCRETE CRADLE, THEN THE STRUCTURAL
PORTIONS OF THE STORMWATER CONTROL MEASURE, KEY TRENCH, ETC.). THEREFORE, THE CONTRACTOR SHALL FURNISH, INSTALL,
FILL SHOULD BE INSTALLED AND COMPACTED UP TO THE TOP OF CONCRETE CRADLE ELEVATION. ONCE THE STRUCTURAL FILL
OPERATE, AND MAINTAIN ANY PUMPING EQUIPMENT, ETC. NEEDED FOR REMOVAL OF WATER FROM VARIOUS PARTS OF THE
REACHES THE NEXT DOWNSTREAM JUNCTION BOX OR HEADWALL AND IS COMPACTED TO THE ELEVATION OF THE TOP OF THE
STORMWATER CONTROL MEASURE SITE. DURING PLACEMENT OF FILL WITHIN THESE AREAS, THE CONTRACTOR SHALL KEEP THE WATER
CONCRETE CRADLE, EXCAVATE THE CONCRETE CRADLE TRENCH PER THE PROVIDED DETAILS AND CONSTRUCT THE CONCRETE CRADLE
LEVEL BELOW THE BOTTOM OF THE EXCAVATION / CONSTRUCTION AREAS. THE MANNER IN WHICH THE WATER IS REMOVED SHALL BE
AS PER THE PROVIDED CONCRETE CRADLE DETAIL.
SUCH THAT THE EXCAVATION BOTTOM AND SIDE SLOPES ARE STABLE, WITH NO SEDIMENT DISCHARGED FROM THE SITE (I.E. PUMPED
WATER MAY NEED TO BE DIRECTED TO AN APPROVED EROSION CONTROL DEVICE SUCH AS A DIRT BAG (ACF ENVIRONMENTAL), OR
B. IF THE PROPOSED STRUCTURAL FILL IS NOT UTILIZED AS THE FORMWORK FOR THE CONCRETE CRADLE, THEN PRIOR TO
ENGINEER APPROVED EQUIVALENT, PRIOR TO DISCHARGE).
CONSTRUCTING THE STRUCTURAL FILL EMBANKMENT, THE FORMWORK FOR THE CONCRETE CRADLE SHOULD BE INSTALLED ON
EXISTING GROUND AND/OR THE MUD MAT. THE CONCRETE CRADLE SHALL BE CONSTRUCTED PER THE PROVIDED DETAILS
9.
THE GRADES SHOWN ON THIS PLAN ARE FINISHED GRADES. IF THE EXISTING SOIL LAYER AFTER CONSTRUCTION / COMPACTION IS NOT
DETERMINED SUITABLE BY A LANDSCAPE PROFESSIONAL FOR THE WETLAND PLANTINGS, THEN THE CONTRACTOR SHALL AMEND THE
10.
AS AN ALTERNATE TO A CONCRETE CRADLE UNDER THE BARREL PIPE (SEE SHEET C9.03), THE CONTRACTOR MAY CHOOSE TO ELIMINATE
PLANTING AREA OF THE WETLAND AS DIRECTED BY A LANDSCAPE PROFESSIONAL.
THE CONCRETE CRADLE AND USE COMPACTED BACKFILL IF THE ON -SITE GEOTECHNICAL ENGINEER WILL PROVIDE A NC PE SEALED LETTER
CERTIFYING THAT THE COMPACTION UNDER, AROUND, AND ABOVE THE BARREL MEETS THE SPECIFICATIONS OF THE EMBANKMENT
10.
PRIOR TO TOPSOIL INSTALLATION, THE CONTRACTOR SHALL SCARIFY THE TOP 2"-3" OF THE BERM SECTION TO PROMOTE BONDING OF
COMPACTION REQUIREMENTS AND MOISTURE CONTENT. THIS CERTIFICATION LETTER MUST BE SUBMITTED TO THE DESIGN ENGINEER
THE TOPSOIL WITH THE COMPACTED FILL. THE TOPSOIL DEPTH SHALL RANGE FROM 3C-4" ON THE DAM EMBANKMENT AND THE
PRIOR TO BACKFILL. THIS SEPARATE CERTIFICATION MUST BE SPECIFIC TO THE BARREL PIPE FOR THE FACILITY AND MUST CLEARLY STATE
WETLAND. PLEASE NOTE THE TOPSOIL SHALL BE AMENDED, AS DIRECTED BY A LANDSCAPE PROFESSIONAL, PRIOR TO INSTALLATION ON
THAT ALL SOIL MATERIAL UNDER, AROUND, AND ABOVE THE BARREL PIPE MEETS THE BERM AND SOIL COMPACTION SPECIFICATIONS ON
THE EMBANKMENT AND WETLAND.
THIS SHEET. THIS CERTIFICATION IS TO INCLUDE REFERENCE TO BOTH MATERIAL AND COMPACTION, AND MUST STATE THAT ALL
0
AND ABOVE THE BARREL HAVE BEEN COMPACTED PER THE BERM MATERIAL SPECIFICATIONS AT LEAST 95/0
MATERIALS UNDER AROUND (
11.
THE CONTRACTOR SHALL REFER TO THE LANDSCAPE PLAN FOR THE PERMANENT PLANTING PLAN/SCHEDULE FOR THIS FACILITY.
OF MAXIMUM DRY DENSITY USING ASTM D698 STANDARD PROCTOR) WITH NO VOID SPACES PRESENT. THE CONTRACTORS INTENT TO
CONTRACTOR SHALL COORDINATE WITH A LANDSCAPE PROFESSIONAL REGARDING SCHEDULING FOR PLANT INSTALLATION. PLEASE NOTE
UTILIZE THIS ALTERNATIVE MUST BE STATED PRIOR TO CONSTRUCTION TAKING PLACE. THIS CONTRACTORS CERTIFICATION MUST BE
THAT NO TREES/SHRUBS OF ANY TYPE MAY BE PLANTED ON THE PROPOSED DAM EMBANKMENT (FILL AREAS).
PRESENTED TO THE DESIGN ENGINEER BEFORE AN AS -BUILT CERTIFICATION CAN BE ISSUED FOR THIS FACILITY.
11.
INSTALL RISER / BARREL ASSEMBLY, ALONG WITH THE EMERGENCY DRAIN SYSTEM. INSTALL 18" RCP OUTLET BARREL SPILLWAY FILTER
OUTLET STRUCTURE MATERIAL SPECIFICATIONS
FROM THE DETAILS SHOWN ON SHEET C9.03.
1.
THE 18" 0 RCP OUTLET BARREL SHALL BE CLASS III RCP, MODIFIED BELL AND SPIGOT, MEETING THE REQUIREMENTS OF ASTM C76-LATEST.
12.
CONSTRUCT EMBANKMENT PER SPECIFICATIONS LISTED IN THE SECTION TITLED "BERM AND SOIL COMPACTION SPECIFICATIONS" AND
THE PIPES SHALL HAVE CONFINED O-RING RUBBER GASKET JOINTS MEETING ASTM C-443-LATEST. THE PIPE JOINTS SHALL BE TYPE R-4.
REQUIREMENTS OF THE ON -SITE GEOTECHNICAL ENGINEER. ALL CHARACTERISTICS OF THE EMBANKMENT FILL MATERIAL SHALL MEET THE
STANDARDS SET FORTH IN "BERM AND SOIL COMPACTION SPECIFICATIONS", INCLUDING COMPACTION AND MOISTURE REQUIREMENTS. IF
2.
THE STRUCTURAL DESIGN FOR THE 4' X 4' INTERNAL DIMENSIONS RISER BOX WITH EXTENDED BASE SHALL BE BY OTHERS. PRIOR TO
( )
NECESSARY TO ACHIEVE PROPER COMPACTION, THE EMBANKMENT FILL MATERIAL WILL BE OVERBUILT IN HORIZONTAL LIFTS AND CUT
ORDERING THE STRUCTURES THE CONTRACTOR SHALL PROVIDE TO THE DESIGN ENGINEER FOR REVIEW SHOP DRAWINGS AND
BACK TO PROPER FINAL GRADE. ANY HAND COMPACTION ACTIVITIES AROUND SPILLWAY OR DRAIN STRUCTURES SHALL BE CONDUCTED IN
SUPPORTING STRUCTURAL CALCULATIONS SEALED BY A P.E. REGISTERED IN NORTH CAROLINA DEMONSTRATING THE PERTINENT VERTICAL
4-INCH LOOSE LIFTS AND BE TO THE SAME COMPACTION AND MOISTURE REQUIREMENTS AS THE ENTIRE EMBANKMENT. ALL
LOADS ARE SUPPORTED BY THE CONCRETE RISER STRUCTURE.
COMPACTION AND MOISTURE TESTING SHALL BE CARRIED OUT AS DIRECTED BY THE ON -SITE GEOTECHNICAL ENGINEER AND AS LISTED IN
THE SECTION TITLED "BERM AND SOIL COMPACTION SPECIFICATIONS".
3.
THE RISER BOX OUTLET STRUCTURE SHALL BE PROVIDED WITH STEPS 16" ON CENTER. STEPS SHALL BE PROVIDED ON THE INNER WALL OF
THE RISER BOX. STEPS SHALL BE IN ACCORDANCE WITH NCDOT STD. 840.66. PLEASE REFER TO SHEET C9.02 FOR LOCATION OF THE RISER
13.
UPON COMPLETION OF DAM EMBANKMENT, PROMPTLY STABILIZE AND SEED DAM EMBANKMENT PER SEEDING SCHEDULE. PERMANENT
STEPS. NOTE THE STEPS SHALL LINE UP WITH THE ACCESS HATCH OF THE TRASH RACK.
GROUND COVER SHALL BE ESTABLISHED PER THE PERMANENT SEEDING SCHEDULE FOUND ON SHEET C9.04.
4.
THE CONCRETE ANTI -FLOTATION BLOCK SHALL BE CAST -IN -PLACE. STEEL REINFORCEMENT AND CONNECTION TO THE RISER SHALL BE
14.
SCHEDULE A FINAL AS -BUILT INSPECTION AND AS -BUILT SURVEY WITH THE ENGINEER AND SURVEYOR. AN AS -BUILT INSPECTION AND
PROVIDED IN ACCORDANCE WITH THE DETAIL ON SHEET C9.03. THE CONTRACTOR SHALL ENSURE THE WEIGHT OF THE ENTIRE RISER
SURVEY SHALL BE SCHEDULED BEFORE IMPOUNDING WATER IN THE FACILITY AND A MINIMUM OF 60 DAYS PRIOR TO THE ANTICIPATED
STRUCTURE IS GREATER THAN OR EQUAL TO 13,193 LBS. IN LIEU OF CAST -IN -PLACE, THE CONTRACTOR MAY OPT FOR A PRECAST
DATE OF CERTIFICATION APPROVAL. ANY COMMENTS OR DEFICIENCIES IN THE SCM CONSTRUCTION MUST BE CORRECTED TO THE
ANTI -FLOTATION BLOCK. SHOP DRAWINGS FOR THE PRECAST BLOCK SHALL BE SUBMITTED TO THE ENGINEER FOR REVIEW. THE PRECAST
SATISFACTION OF THE ENGINEER AND OWNER BEFORE CERTIFICATION SHALL BE GRANTED.
ANTI -FLOTATION BLOCK SHALL HAVE A SHIPPING WEIGHT OF 9,088 LBS.
BERM AND SOIL COMPACTION SPECIFICATIONS
5.
THE RISER BOX JOINTS SHALL BE SEALED USING BUTYL RUBBER SEALANT CONFORMING TO ASTM -C990- LATEST. IF NECESSARY, THE
CONTRACTOR SHALL INCORPORATE A WATERSTOP INTO THE RISER BOX JOINTTO ENSURE A WATERTIGHT CONNECTION. THE
1.
PRIOR TO CONSTRUCTION, THE ON -SITE GEOTECHNICAL ENGINEER SHALL IDENTIFY BORROW / FILL AREAS AND VERIFY THEIR SUITABILITY
CONTRACTOR SHALL PARGE JOINTS ON BOTH THE INSIDE AND OUTSIDE WITH NON -SHRINK GROUT AND INSTALL GALVANIZED STEEL
FOR USE WITHIN THE DAM EMBANKMENT. ALSO, THE ON -SITE GEOTECHNICAL ENGINEER SHALL PERFORM STANDARD PROCTORS ON THE
STRAPS PER DETAIL ON SHEET C9.02.
PROPOSED BORROW MATERIAL TO ENSURE THAT OPTIMUM MOISTURE CONTENT AND COMPACTION CAN BE ACHIEVED / CONTROLLED
DURING CONSTRUCTION.
6.
PRIOR TO ORDERING, THE CONTRACTOR SHALL SUBMIT TRASH RACK SHOP DRAWINGS TO THE ENGINEER FOR REVIEW. CONTRACTOR
SHALL ENSURE THAT AN ACCESS HATCH IS PROVIDED WITHIN THE TRASH RACK SEE DETAIL FOR LOCATION THAT WILL ALLOW FOR
2.
ALL FILL MATERIALS TO BE USED FOR THE DAM EMBANKMENT SHALL BE TAKEN FROM BORROW AREAS APPROVED BY THE ON -SITE
FUTURE MAINTENANCE ACCESS. CONTRACTOR SHALL ALSO PROVIDE A CHAIN AND LOCK FOR SECURING THE ACCESS HATCH. NOTE THE
GEOTECHNICAL ENGINEER. THE FILL MATERIAL SHALL BE FREE FROM ROOTS, STUMPS, WOOD, STONES GREATER THAN 6", AND FROZEN
ACCESS HATCH SHALL LINE UP WITH THE ACCESS STEPS AFTER INSTALLATION.
OR OTHER OBJECTIONABLE MATERIAL. THE FOLLOWING SOIL TYPES ARE SUITABLE FOR USE AS FILL WITHIN THE DAM EMBANKMENT AND
KEY TRENCH: ML AND CL. ALL FILL MATERIALS SHALL BE APPROVED BY THE ONSITE GEOTECHNICAL ENGINEER FOR THE INTENDED USE.
7.
ALL POURED CONCRETE SHALL MEET THE FOLLOWING SPECIFICATIONS UNLESS OTHERWISE NOTED:
3.
FILL PLACEMENT FOR THE EMBANKMENT SHALL NOT EXCEED A MAXIMUM 8" LIFT (UNCOMPACTED). EACH LIFT SHALL BE CONTINUOUS
-MINIMUM 3000 PSI (28 DAY)
FOR THE ENTIRE LENGTH OF EMBANKMENT. BEFORE PLACEMENT OF FILL FOR THE BERM SECTION, ALL UNSUITABLE MATERIAL SHALL BE
-SLUMP = 3" - 5"
REMOVED AND THE SURFACE PROPERLY PREPARED FOR FILL PLACEMENT. FILL MATERIAL ADJACENT TO ALL SPILLWAY AND DRAINAGE
STRUCTURES SHALL BE PLACED IN 4-INCH (UNCOMPACTED) LIFTS AND HAND -COMPACTED TO THE SAME COMPACTION AND MOISTURE
-ENTRAINED AIR = 5%- 7%
REQUIREMENTS AS THE ENTIRE EMBANKMENT.
PLEASE NOTE NO CONCRETE SHALL BE POURED WHEN THE AMBIENT AIR TEMPERATURES ARE EXPECTED TO BE ABOVE 85°F OR BELOW
4.
ALL FILL SOILS USED IN THE EMBANKMENT CONSTRUCTION SHALL BE COMPACTED TO AT LEAST 95% OF THE STANDARD PROCTOR
40°F. CAST -IN -PLACE CONCRETE SHALL BE "WET CURED" AFTER FINISHING FOR A MINIMUM OF 48 HOURS.
MAXIMUM DRY DENSITY (ASTM D-698). THE FILL SOILS SHALL BE COMPACTED AT A MOISTURE CONTENT WITHIN -1 TO +3 PERCENT OF ITS
OPTIMUM MOISTURE CONTENT. COMPACTION TESTS SHALL BE PERFORMED BY THE ON -SITE GEOTECHNICAL ENGINEER DURING
CONSTRUCTION TO VERIFY THAT THE PROPER COMPACTION LEVEL HAS BEEN REACHED. THE FILL SHOULD BE COMPACTED USING A
ON -SITE GEOTECHNICAL ENGINEER TO ENSURE AND CERTIFY ALL POURED CONCRETE MEETS THE ABOVE SPECIFICATIONS.
SHEEPSFOOT TYPE COMPACTOR. IN ORDER TO PREVENT DAMAGE TO THE PIPE, NO COMPACTION EQUIPMENT SHALL CROSS ANY PIPE
UNTIL MINIMUM COVER IS ESTABLISHED ALONG THE PIPE.
8.
GEOTEXTILE FABRIC FOR THE 18" 0 RCP OUTLET BARREL JOINTS SHALL BE MIRAFI 180N OR ENGINEER APPROVED EQUAL (NON -WOVEN
FABRIC).
5.
THE DESIGN ENGINEER SHALL BE PROVIDED WITH REPORTS AND CERTIFICATION, BY THE ON -SITE GEOTECHNICAL ENGINEER, THAT THE
GEOTECHNICAL ASPECTS OF THE FACILITY HAVE BEEN CONSTRUCTED PER PLAN. THIS CERTIFICATION MUST ADDRESS THE TESTING FOR
9.
STORMWATER CONTROL MEASURE EMERGENCY DRAW DOWN IS VIA AN 6"0 PLUG VALVE. THE VALVE SHALL BE A M&H STYLE 1820
MATERIALS AND COMPACTION OF THE DAM EMBANKMENT AND SPILLWAY. THESE REPORTS AND CERTIFICATION WILL BE NEEDED DURING
ECCENTRIC VALVE OR APPROVED EQUAL. THIS VALVE IS IN ACCORDANCE WITH AWWA C-517, AND SHALL BE OPERABLE FROM TOP OF
THE AS -BUILT CERTIFICATION PROCESS FOR THIS STORMWATER CONTROL MEASURE. THEREFORE, IT SHALL BE THE CONTRACTOR'S
OUTLET STRUCTURE VIA A HAND WHEEL (SEE DETAIL SHEET C9.03). THE CONTRACTOR SHALL PROVIDE A REMOVABLE VALVE WRENCH
RESPONSIBILITY TO COORDINATE TESTING AND OBSERVATION WITH THE ON -SITE GEOTECHNICAL ENGINEER.
WITH A HAND WHEEL ON TOP FOR OPERATION OF THE 6" 0I PLUG VALVE.
6.
TESTING OF THE NEW FILL MATERIALS SHALL BE PERFORMED TO VERIFY THAT THE RECOMMENDED LEVEL OF COMPACTION IS ACHIEVED
DURING CONSTRUCTION. THEREFORE, ONE DENSITY TEST SHALL BE PERFORMED FOR EVERY 2,500 SQUARE FEET OF AREA FOR EVERY LIFT
OF FILL OR AS RECOMMENDED BY THE ON -SITE GEOTECHNICAL ENGINEER.
7.
TESTING WILL BE REQUIRED ALONG THE 18"0 RCP OUTLET BARREL AT A FREQUENCY OF ONE TEST PER 25 LF OF PIPE PER VERTICAL FOOT
OF FILL OR AS DIRECTED BY THE ON -SITE GEOTECHNICAL ENGINEER.
STATEMENT OF RESPONSIBILITY
1. ALL REQUIRED MAINTENANCE AND INSPECTIONS OF THE STORMWATER CONTROL MEASURE SHALL BE THE RESPONSIBILITY OF THE
OWNER, PER THE EXECUTED OPERATION AND MAINTENANCE AGREEMENT FOR THIS FACILITY.
�� \ �-� �-
- I i•- - ou ou ou �- ou ou
j`( I F--I-�-�- ou � ou ou - ��� � i
/� ou _ 1
� OU 5
OU _ i
\ 2�'0`
OU I _ _
I �
2
- 0 PUBLIC R W
Q
E / I
WARREN AV
I Ss S ; I SS SS SS Ss SS SS
s_
ss , - ss SS" Is SS ss ss I
;S SS SS SS SS SS SS I N' LD LD LD LD LD 6 LL
\ - _ Ln w _ -- w - - - - ---- - �---
-wow w -w �v� w �w w
\ _ w
\os µ w w w w 19-z�71--- �73--- --- -q4-
o
s 28 LF 18" 0 CLASS III
0-RING RCP @ 1.79% 271
\ T (JOINTS WRAPPED o ��Z IVY �Z /
IN GEOTEXTILE FABRIC)
\ \
CLASS 'B' RIP RAP / 9LZ _------------
VELOCITY DISSIPATOR PAD - - - -
�/ \ \ 9.01 X 45W X 22"T - ----------...---ti-- ■
\ (SEE DETIAL, SHEET C9.03) I
ig
I +
I \ \ ENDWALL PER i / - - -274.5
I \ \ NCDOT STD. 838.80 i, / \�
\ ' INV. OUT (18" RCP) N / - - ■ ■'■■■■■ ■■■■� II
EL. 271.00
\ I
STORMWATER II �
PRECAST RISER OUTLET STRUCTURE 1 I MANAGEMENT FACILITY
/ 1 274.5 I wa I I I ACCESS EASEMENT
SHAPE = SQUARE 1 I o ^
INTERNAL DIMENSIONS = 4 FT. x 4 FT. I� I '��' a I MICROPOOL II
TOP OF RISER = 273.50 n I I -N`
1'L WEIR INVERT EL. = 273.25 I I I II
4.0" PVC PIPE INVERT EL. = 271.50 1 0 1 I SHALLOW
I I
INVERT OUT (18"0 0-RING RCP) 3:1 SLOPE 271.50 I , �
WATER
� o (TYP.) o l 1
(SEE DETAIL ON SHEET C9.02) I v
I
II I I I I710
> 1 1 + 3:1 SLOPE
II I 271.5 (TYP.) I
I o0
I \\ I I I I I "Cn I Q J I I N +272.5
I \I I r I N I N I I L'
I N
I 272.5
w I rn
I
rn N
271.5
I I I I
\I I TOP OF DAM
I I I 3:1 SLOPE I I
I I I I (TYP.) I
I �
I PROPERTY LINE I 1C + I I I
I II 1CN 272.5 I I
I I (TYP) 1 11 I I
I I � I 1 I III I I I
Iz
I I
! I I SHALLOW I I I
II I I ELEV. = 269.0 I WATER I I \? SHALLOW
+ (FOREBAY EXIT) I I
+ 5 I I LAND
I I� 1+ 1 1 o _jz
I I I 1 274.5 Q a 3:1 SLOPE I I
I I I ELEV. = 268.67 1 1 N J N I I I
I \ \ \ (FOREBAY ENTRANCE) I + °1
272.5 N1 2 (TYP.) SLOPE I CLASS 'B' RIP RAP /
\\ \ I R C° I I I VELOCITY DISSIPATOR PAD
271.5 1
N
\\ � i \ _ _ - - _ _ I ■ CLASS 'B' RIP RAP
\ ■ VELOCITY DISSIPATOR PAD
+ I
■
■ 12.0'L X 6.0'W X 22"T
\ \ 274.5
\ \ \ \ _ _ 0� (SEE DETIAL, SHEET C9.03)
_ - _
\ MICROPOOL 2�3 - MSEE ■
\ ■ - -
STORMWATER
\\ \ I I MANAGEMENT FACILITY
�\ \ ss _ s$ -SS / ACCESS EASEMENT
\ \-_/�-SS-
\ I v - SS �� SS Ss
i s5 -�-
y \
II II I II \
I
I I I i I
11 \ II I
I
2 $ I
� I
STORMWATER CONTROL MEASURE'A' PLAN VIEW
1" = 20'
/ 2j8
T
a� cn 01
a�
LIMITS OF
DISTUBANCE
(TYP)
EXISTING TREE
(TYP)
�J
GRAPHIC SCALE
0 10 20 40
1 inch = 20 ft.
'J
McADAMS
The John R. McAdams Company, Inc.
2905 Meridian Parkway
Durham, INC 27713
phone 919. 361. 5000
fax 919. 361. 2269
license number: C-0293 C-187
www.mcadamsco.com
CLIENT
BODDIE-NOELL ENTERPRISES, INC.
P.O. BOX 1908
ROCKY MOUNT, INC 27802
Contact
PHONE: 252. 937. 2800
W
W
�
Z
W
J
~
Z
a
zO
z
R
Q
z
z
V
z
m
�
M
W
LL1
z
06
000
V
cV
%gill 111#1"1"
CA
R
R
O
ESS/�• '�' C� 51,
•• ti
SEAL
20744
��•�/k�' NEB-��� 02/22
'i '•••......••�
REVISIONS
NO. DATE
1
2
3
4
5
6
PLAN INFORMATION
PROJECT NO
FILENAME
CHECKED BY
DRAWN BY
SCALE
DATE
SHEET
2021110321
2021110321-SW
RW
KEG
1"=20'
06.21.2022
STORMWATER CONTROL
MEASURE 'A'
C9601
PRELIMINARY DRAWING - NOT RELEASED FOR CONSTRUCTION