Western Australian Current Regulations Western Australian Current Regulations[Reg. 49(1)]
[Heading inserted: Gazette 15 Dec 1989
p. 4552.]
Form No. 1
‘D’ & ‘C’ TO BE AT COURSE HEIGHT BUT NOT LESS
THAN
1200 FOR ‘C’ AND 1500 FOR ‘D’.
Soak Well — To be constructed as shown on plan, having the
3 top courses or all courses above the overt to be set in 2 in 1 cement
mortar, the remainder in open jointed brickwork, laid dry, in stretcher
courses, or constructed in approved cement segments or bricks which comply
with the standard for blocks, class A.A.S. A87‑1963.
Size — Bricks or segments shall have a minimum bearing face of
100 mm and shall be laid over the full bearing face in each course.
Sufficient openings shall be provided in any soak well to allow for the
efficient disposal of the effluent, and shall be not less than 10% of the
surface area.
Inspection Openings and square junction to be provided as shown.
When completed it shall show a circular, smooth and regular internal surface.
All soak wells shall be 1.2 m in dia. and with a 1.5 m effective depth unless
otherwise specified or approved by the local government.
The top of the soak well shall not be more than 300 mm or less than 150 mm
below ground level, unless otherwise approved by the local government.
Soak wells in series shall have a long square on the outlet as shown.
Cover — Shall be of concrete in section with rebated joint as
shown, reinforced with No. F.41 steel mesh fabric, joints of mesh shall be
securely tied with a full 2 mesh overlap, unless otherwise specified.
The covers shall withstand a flexural test of 2 MPa and a load bearing of 7
kPa.
Traffic covers shall be constructed to specific Departmental specifications.
No soak well shall be situated closer than 1.8 m to any building, boundary
fence or septic tank, unless otherwise approved by the local government.
[Form 1 amended: Gazette
29 Jul 1997 p. 4084; 5 Sep 1997 p. 5037.]
Form No. 2
Specifications
Trench to be not less than 9 m long, constructed as shown.
Filling to consist of 50 mm or 75 mm gauge broken blue metal; filling on top
may be of smaller gauge metal with sand over approved sheeting.
Distributing pipe to be 75 mm or 100 mm diameter unglazed agricultural pipes
laid with open butt joints, or other approved piping.
Grade shall be laid at not more than 1 in 200.
A French drain shall not be situated closer than 3.5 m from any dwelling nor
closer than 6 m from any window or door of any dwelling, nor closer than 1.8 m
from any lot boundary, unless otherwise approved by the local government.
[Form 2 amended: Gazette
29 Jul 1997 p. 4084.]
Form No. 3
SEMI INVERTED TYPE LEACH DRAIN 
FULLY INVERTED TYPE LEACH DRAIN
SECTION A ‑ A.
DETAILS OF LEACH DRAIN.
THE DRAIN SHALL NOT BE SITUATED CLOSER THAN 2000 FROM
ANY SEPTIC TANK, BUILDING OR BOUNDARY OF A LOT, UNLESS OTHERWISE APPROVED BY
THE LOCAL GOVERNMENT.
MINIMUM LENGTH BLACKWATER SYSTEMS TO HAVE DRAIN 6000
LONG COMBINED SYSTEMS TO HAVE DRAIN 9000 LONG
REINFORCED CONCRETE PAVING SLABS
POSITIONED BENEATH INLET AND BRICK SPREADER WALLS PROVIDED NOT MORE THAN 1200
cts
SEGMENTS WHERE SEGMENTS ARE USED ALL COURSES ABOVE THE OVERT OF THE INLET
TO BE LAID 3:1 CEMENT MORTAR.
[Form 3 amended: Gazette
29 Jul 1997 p. 4084; 7 Jan 2005 p. 70.]
Form No. 4
