Western Australian Current Regulations Western Australian Current Regulations (1) When the capacity
of a septic tank exceeds 2 045 litres the tank shall be divided into
2 chambers by means of a fixed durable partition, and the partition shall
be located so that the capacity of the first chamber is twice that of the
second chamber.
(2) Suitable openings
with a full unobstructed area of not less than 0.015 m 2 shall be provided in
the partition at approximately half the liquid depth in the tank and so placed
as to ensure the maximum length of flow through the tank.