Attachment G - Stormwater Quality Management plan

 

Field inlet Type 1 without
concrete apron as per
(IPWEAQ Std Dwg D—-0050)

Filter cloth, refer note 4 or organic
geotextile matting fixed to perimeter of pit
to avoid runnelling of water between pit
and soil interface. 300 wide, 100 cover

Extended detention depth 100 to

 

 

 

 

 

 

 

Bioretention basin finished surface level,
refer project drawings and notes 6 and 7

refer project drawings for depth

Transition layer — coarse sand,

Refer note 1

 

——— Drainage layer — fine aggregate,

 

 

 

 

 

 

Posy 300 (typically 300), refer project
drawings
782 Vegetated surface,
4 ol | Slo refer iy 7
v ” “\/ Bf \/ ——— Mulch layer, 50-75
. v > VY refer note 5
itr , Overflow pit L ~~

y

I >

Ivo vy
Filter cloth to extend |
500 up batter under | > ——— Filter media — loamy sand,
topsoil pinned to batter, vy .
refer note 4 I. , Pipe sealed “90 MIN. cover of drainage layer 500 (typical), 400 MIN

| » into pit (fine aggregate) over subsoil

' ° drainage pipe

Ie ’ =——— constant depth — 100,

{ r yA nom. size 0.5-2.0

\-°

¥ flow Under—drain, refer note 2 constant depth — 200,

yoy ot ee nom. size 2-5

| a Basin base to grade at 0.5% MIN,

* refer note 6

 

 

 

 

 

NOTES:

Bioretention media specification shall be in accordance with the Facility for

Filter cloth, refer note 4

BIORETENTION BASIN OVERFLOW PIT DETAIL

Advancing Biofiltration 4. Filter cloth — non-woven geotextile.

Filter cloth not to be placed between any filter layers.

"Guidelines for Soil Filter Media in Bioretention Systems”.
accordance with the Facility for Advancing Biofiltration ’Practice Note 1:

Bioretention hydraulic conductivity shall be in
In Situ Measurement of

Hydraulic Conductivity”. The number of samples to be tested shall be in accordance with the "Water
Sensitive Urban Design Construction and Establishment Guidelines — Swales, Bioretention Systems and

Wetlands (Water by Design).

2. Under—drain: slotted rigid pipe (uPVC or similar to AS 2439.1) or approved equivalent, 0.5% MIN. grade.

Impervious

liner may be required subject to soil testing requirements in accordance with the "Water Sensitive
Urban Design Technical Design Guidelines” (Water by Design).

"Water Sensitive Urban Design Construction and

Refer project drawings for diameter and invert level (Typically 100-150).

Surface to be mulched and planted as per

Establishment Guidelines — Swales, Bioretention Systems and Wetlands” (Water by Design) must be

with a filter sock surrounding pipe. Under—drainage pipes shall be sealed into pits using grout or other
approved watertight seal.

3. Refer to project drawings for vegetated batter slopes (1 in 3 MAX, 1 in 4 typical) and batter topsoil

requirements.

achieved. Construction tolerances must be noted on project plans. Invert levels of pits, pipes and base

Refer landscape drawings for plant specification. Plant specification and density shall be in accordance
with the "Water Sensitive Urban Design Technical Design Guidelines” (Water by Design).

5. Basin finished surface level is top of filter media.
landscape drawings.
6. Construction tolerances as documented in the
Pipe should not be installed
levels must be noted on project drawings.
7.
8. All dimensions are in millimetres unless otherwise noted.

These drawings have been developed in consultation between the participating councils.
BEFORE USE, the user shall confirm that the drawing has been adopted by the appropriate council

 

 

 

 

 

 

13/01/2010

ORIGINAL _ISSUE

 

 

 

2>

DATE.

 

REVISIONS.

 

Q

INSTITUTE OF PUBLIC WORKS ENGINEERING AUSTRALIA
QUEENSLAND DIMISION INC.
STANDARD DRAWINGS

 

BIORETENTION STANDARD PROFILE

OVERFLOW PIT

DRAWING No.

 

WSUD-001

 

 

 

2-T TTT]