16-001014-400(A)

 

BIO_RETENTION BASIN CONSTRUCTION SEQUENCE NOTES:
THE CONSTRUCTION AND ESTABLISHMENT OF BIO RETENTION BASINS IS TO BE STAGED AS FOLLOWS:

1.

FUNCTIONAL INSTALLATION - ONCE THE MAJORITY OF THE SUBDIVISION WORKS ARE COMPLETE, THE
BASIN CONSTRUCTION INCLUDING EARTHWORKS, INLETS, OUTLET STRUCTURES, SUBSOIL DRAINAGE,
TRANSITION LAYERS, FILTER MATERIAL, PROTECTIVE LAYERS AND EROSION AND SEDIMENT CONTROL
MEASURES ARE TO BE UNDERTAKEN BY THE CIVIL CONTRACTOR. THE FILTER MEDIA WITHIN THE BIO
RETENTION BASIN IS TO BE COVERED WITH A PROTECTIVE GEOFABRIC LAYER (BIDIM A12 OR
EQUIVALENT), THEN COVERED WITH 75mm OF TOPSOIL AND TURFED OR GRASS SEEDED TO THE
SATISFACTION OF COUNCIL. SILT FENCES ARE TO BE ERECTED AROUND THE OUTSIDE OF THE BASIN.
ACCEPTANCE OF THE COMPLETED SUBDIVISION WORKS ON AND OFF MAINTENANCE BY COUNCIL IS TO
EXCLUDE THE PROTECTIVE LAYERS WITHIN THE BIO BASINS.

BUILDING CONSTRUCTION - THE PROTECTIVE GEOFABRIC AND GRASS LAYER AND THE EROSION AND
SEDIMENT CONTROL MEASURES ARE TO REMAIN IN PLACE DURING THE BUILDING CONSTRUCTION PHASE.
THE BUILDING CONSTRUCTION PHASE IS TO BE THE TIME FOR COMPLETION OF 75% OF THE BUILDING
CONSTRUCTION AND SITE ESTABLISHMENT WORKS ON ALLOTMENTS OR 12 MONTHS FOLLOWING
COMPLETION OF THE SUBDIVISION WORKS, WHICHEVER IS SHORTER. THE MAINTENANCE OF THE BASINS
INCLUDING INLETS, OUTLETS AND EROSION AND SEDIMENT CONTROL MEASURES IS TO BE UNDERTAKEN
BY THE CIVIL CONTRACTOR FOR THE DURATION OF THE BUILDING CONSTRUCTION PHASE.
OPERATIONAL ESTABLISHMENT - FOLLOWING COMPLETION OF THE BUILDING CONSTRUCTION PHASE, THE
TURF, TOPSOIL AND PROTECTIVE GEOFABRIC IS TO BE REMOVED AND THE BASIN RE-PLANTED WITH
VEGETATION AND LANDSCAPING AS PER THE LANDSCAPE DESIGN DRAWINGS. WORKS UNDERTAKEN FOR
OPERATIONAL ESTABLISHMENT ARE TO BE UNDERTAKEN BY OTHERS AND WILL BE SUBJECT TO A
SEPARATE ACCEPTANCE BY COUNCIL FOR ON AND OFF MAINTENANCE.

IN-SITU_INFILTRATION TEST - AN IN-SITU INFILTRATION TEST WILL BE REQUIRED PRIOR TO
ON-MAINTENANCE BEING GRANTED BY COUNCIL. THE TEST WILL NEED TO ACHIEVE AN AVERAGE RATE
OF 180mm/h INFILTRATION (WITHIN APPROPRIATE TOLERANCES) WITH AT LEAST 4 SAMPLE LOCATIONS
AROUND THE BASIN. ANOTHER IN-SITU INFILTRATION TEST WILL BE REQUIRED FOR OFF-MAINTENANCE.

BIO RETENTION PARTICLE SIZE DISTRIBUTION AND PROPERTIES GUIDE:

BIO_RETENTION INSTALLATION NOTES:

THE PLACEMENT OF DRAINAGE, TRANSITION AND FILTER MEDIA
LAYERS MUST BE UNDERTAKEN CAREFULLY TO ENSURE CORRECT
DEPTH, SLOPE AND COMPACTION:

DEPTH: FILTER MEDIA SHOULD BE INSTALLED AND COMPACTED IN
TWO LIFTS FOR DEPTHS OVER 500mm.

SLOPE: THE TOP SURFACE OF THE DRAINAGE LAYER, TRANSITION
LAYER AND FILTER MEDIA LAYER SHOULD BE FLAT. A
SPREADER BAR SHOULD LEVEL THE SURFACE OF EACH LAYER.
COMPACTION: THE FILTER MEDIA MUST BE LIGHTLY COMPACTED
DURING INSTALLATION TO PREVENT THE MIGRATION OF FINE
PARTICLES. THIS CAN BE ACHIEVED WITH A SINGLE PASS OF A
LIGHT ROLLER SUCH AS A DRUM LAWN ROLLER. A VIBRATING
PLATE CAN ALSO BE USED TO COMPACT SMALL BIO RETENTION
SYSTEMS OR ‘POZITRACK’ BOBCATS CAN BE USED FOR LARGE
SYSTEMS. ENSURE ONLY ONE COMPACTING PASS IS MADE OVER
THE MEDIA FOR LIGHT COMPACTION.

ROCK ARMOURING NOTES:
14. ROCKS TO BE DURABLE BLUE STONE OR OTHERWISE
APPROVED BY SUPERINTENDENT.
2. EACH ROCK SHALL BE:
- ANGULAR IN SHAPE (PROMOTES INTERLOCKING)
- FREE FROM OVERBURDEN, SPOIL, SHALE AND
ORGANIC MATERIAL.
3. NEITHER BREADTH NOR THICKNESS OF A SINGLE ROCK SHALL
BE LESS THAN ONE HALF ITS LENGTH {ie THE ROCK SHALL
BE CHUNKY RATHER THAN FLAT).
4. ROCKS TO BE PLACED AND INTERLOCKED INTO POSITION AND

150 SUBSOIL DRAIN CLEANOUT
- PVC PIPE (NON SLOTTED) AND
CONNECTOR CLEANOUTS AT HEAD

GRAVEL DRAINAGE LAYER -
DEPTH 200mm. (NO FINES)

SOURCE: (BIOFILTRATION MEDIA GUIDELINES (VERSION 3.01), PREPARED BY THE FACILITY FOR ADVANCING
WATER BIOFILTRATION (FAWB), JUNE 2009.) & (BIO-RETENTION TECHNICAL DESIGN GUIDELINES (VERSION 1)

PREPARED BY ‘WATER BY DESIGN’ (OCTOBER 2012)

MATERIAL COMPOSITION RANGE GUIDE:

CLAY AND SILT <3% (<0.05mm)
VERY FINE SAND 5-30% (0.05-0.1Smm)
FINE SAND 10-30% (0.15-0.25mm)
MEDIUM TO COARSE SAND 40-60% (0.25-1.0mm)
COARSE SAND 71-10% (1.0-2.0mm)
FINE GRAVEL <3.0% (2.0-3.4mm)

WHILE TOTAL CLAY AND SILT CONTENT OF 3% IS RECOMMENDED, A CLAY AND SILT CONTENT UP TO 6%
IS ACCEPTABLE PROVIDED:

THE SATURATED HYDRAULIC CONDUCTIVITY IS BETWEEN 100mm/hr & 300mm/hr AND
THE REMAINING MATERIAL MEETS THE COMPOSITION RANGE SPECIFIED ABOVE.

SOIL_SPECIFICATIONS:

FOREBAY SLAB - 125mm THICK

ENDWALL
CONCRETE, SL62 REINFORCING, 50 TOP COVER ee
SLEEVES AT 0.5m CENTRES
m —— 100 AG PIPE
REFER DETAIL A 100% ROCK SCOUR PROTECTION OVER
1 | ti) __ GEOFABRIC TO PERIMETER OF
dh L SRR FOREBAY WEIR AT 1.0m CENTERS.
z ZG Z
YSIS SSSPS SY <| g
USINSITU SOIL TO REMAIN UNDER SAAS \ g|
COARSE, SEDIMENT, FOREBAY, RRR, L= NO FINE CONCRETE

TOTAL NITROGEN CONTENT - <1000mg/kg

ORTHOPHOSPHATE CONTENT - <80mg/kg SOILS WITH TOTAL PHOSPHORUS CONCENTRATIONS >100mg/kg
SHOULD BE TESTED FOR POTENTIAL LEACHING. WHERE PLANTS WITH MODERATE PHOSPHORUS
SENSITIVITY ARE TO BE USED, TOTAL PHOSPHORUS CONCENTRATIONS SHOULD BE <20mg/kg)

ORGANIC MATTER CONTENT - AT LEAST 3% (w/w). AN ORGANIC CONTENT LOWER THAN 3% IS
LIKELY TO HAVE TOO LOW A WATER HOLDING CAPACITY TO SUPPORT HEALTHY PLANT GROWTH. IN
ORDER TO COMPLY WITH BOTH THIS AND THE TOTAL NITROGEN AND ORTHOPHOSPHATE CONTENT
REQUIREMENTS, A LOW NUTRIENT ORGANIC MATTER WILL BE REQUIRED.

pH - AS SPECIFIED FOR ‘NATURAL SOILS AND SOIL BLENDS’ 5.5-7.5 (pH 1:5 IN WATER)

ELECTRICAL CONDUCTIVITY - AS SPECIFIED FOR ‘NATURAL SOILS AND SOIL BLENDS’ <1.2 dS/m.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

NOTE: LAY GEOFABRIC OVER INSITU SOIL.
(EXTEND MINIMUM 300mm UNDER FOREBAY)
PIN GEOFABRIC TO INSITU SOIL AND FORM
CONCRETE ONTO GEOFABRIC.

BUILT UP TO FINAL LEVELS SHOWN, ENSURING COVERAGE OF

GEOFABRIC.

GAPS BETWEEN THE ROCKS ARE TO BE FILLED BY DROPPING
SMALL ROCKS INTO GAPS AND LOCKING INTO POSITION WITH

A CROWBAR.

Cl. CAP. EXTEND CAP TO
APPROX. 50-100mm ABOVE
BIORETENTION SURFACE. SCREW

  
  
 
 
  
   

CAP FIXED USING 3 ~\

OF SUBSOIL DRAIN AND AS
SHOWN ON PLAN

5-7mm AGGREGATE

UPVC JOINT FOR
RISER CONNECTION
TO SLOTTED PIPE

EPOXY SADDLE JOINT
TO TRUNK MAIN

200m W x 150m D CONCRETE
SURROUND TO CLEANOUT RISER

YW

    

  

 

 

COLLECTOR PIPE MAX 2.5m SPACINGS

BIO RETENTION BASIN SUBSOIL DRAIN

CLEANOUT AND FILTER MEDIA SPECIFICATIONS

PROVIDE 300mm THICK CONCRETE
INFILL ENDWALL AROUND PPE)

SCALE: 1:20(A1)

0.15m_ MIN ALL AROUND

 

FILTER MEDIA LOAM -

  

400mm DEPTH CONSISTENT WITH
CURRENT FAWB SPECIFICATIONS.
FILTER MEDIAN PARTICLE DIA
0.45m MIN. HYDRAULIC
maf CONDUCTIVITY 200mm/hr
|

COARSE SAND TRANSITION
LAYER - 100mm DEPTH
(imm PARTICLE DIA.)

PROVIDE BIDUM A12 OR

i Cievennenieeiel EQUIVALENT TO EXTENTS

SMOOTH WALLED SLOTTED PVC
PIPE- MIN 0.5% GRADE AND

 

NOTE:

 

I

| yt

 

OT

 

 

 

APPROPRIATENESS OF GEOTEXTILE LINER AS
AN ALTERNATIVE TO HDPE LINER TO BE
ASSESSED BY GEOTECHNICAL ENGINEER AT
CONSTRUCTION STAGE FOLLOWING TESTING OF

6. ALL ROCKWORK TO BE PLACED OVER BIDIM A24 OR
EQUIVALENT.

7. FOR ROCK SIZED SPECIFIED AS Dso ON THE DRAWINGS, THIS
CORRESPONDS TO THE MEDIAN DIAMETER OF WHICH HALF OF
THE ROCK SIZES SHALL BE GREATER AND HALF OF THEM
SHALL BE SMALLER. THE ROCK SHALL BE WELL GRADED
AND HAVE A MAXIMUM SIZE NO GREATER THAN 30% AND A
MINIMUM SIZE NO LESS THAN 30% SMALLER THAN Dso. FOR
EXAMPLE IF Dso = 400mm IS SPECIFIED, THE EQUIVALENT
ROCK DIAMETER RANGES FROM 280 to 520mm.

TURF REINFORCED WITH ENKAMAT OR

APPROVED EQUIVALENT INSTALLATION NOTES:

1. PREPARE AND COMPACT BASE SURFACE. EXCAVATE ANCHOR
TRENCHES AT TOE AND SHOULDER OF BANK, TO BE
BACKFILLED AFTER LAYING TURF.

2. LAY ENKAMAT OR APPROVED EQUIVALENT AND PIN TO
MANUFACTURERS SPECIFICATIONS.

3. LAY TOPSOIL AND PLACE TURF.

SAFETY FENCE TO

LANDSCAPE ;
ARCHITECTS DETAIL————~—

 

PERMEABLE
GEOTEXTILE
MEMBRANE

GRANULAR FILL:

 

 

 

 

1.0m WIDE, 0.45m DEEP, 0.20m INSITU_ SOILS.

 

 

THICK CONCRETE (SL81 MESH
CENTRAL) SUPPORT UNDER PIPE

TYPICAL OUTLET THROUGH ROCKWALL DETAIL
SCALE 1:50 (A)

REFER DRG. 16-001014-105
FOR FURTHER ROCK
BOULDER WALL DETAILS

   
  

300mm

 

TEMP. PONDING LEVEL

 

 

BASE OF
BIO RETENTION
FILTER MATERIAL

SAFETY FENCE TO
LANDSCAPE y
ARCHITECTS DETAIL.

REFER

    
  
 

 

    
   
   

PERMEABLE
GEOTEXTILE
MEMBRANE

300mm

GRANULAR FILL:

 

100D AG PIPE

NO FINE CONCRETE:

DRG. 16-001014-105

FOR FURTHER ROCK
BOULDER WALL DETAILS

TEMP. PONDING LEVEL

BASIN SL: 100.05m AHD

BASE OF
BIO RETENTION
FILTER MATERIAL

 

 

 

WOOE

 

Ee
SOUTHERN BIO-RETENTION BASIN TYPICAL

 

w
Ss
Ss
3
3

 

CENTRAL BIO-RETENTION BASIN TYPICAL

 

 

 

 

 

 

 

 

 

 

 

 

 

TYPICAL SECTION THROUGH FOREBAY DETAIL A RETAINING WALL SECTION
SCALE 150 (41) SCALE 120 (A1) RETAINING WALL SECTION SCALE: N.T.S.
SCALE: N.T.S.
N.S.C. REF NO. MCU15/0111 & REC15/0031

fst [ccs oem] _oaTE [AMENDMENT DETAILS DesIGN CHECK sous (ems) menor SURVEYOR: ML SURVEYS oer a —
afk $ 7 oo ISSUED FOR CONSTRUCTION — PENOING COUNCIL APPROVAL cM to 1 0s 1 aM 78, Leybourne TBE [email protected] _PAM LAKE WORKS PTY LTD " CONSULT AUSTRALIA eae ortAIe
fe eam cnr] 1° 2) meget, [ame 1 PALM LAKE RESORT ih core cnaig (0 Py ny
é D 16-001014 y ANDREW MCPHAIL RPEQ 6921 COOROY Ca I re Grae Fr, 55 Quen Sr, Bore, GL Ain 400 ESOS FSS area pease roy
8 F cM 6-0010 ron » ov bout caste YnsieTHG (ato) PTY LT STAGE 2 CONSULTING Ce sts nos tn Se snc ‘oi 16-001014-400 A