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Environment and Health
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chlorination and a possible
carcinogen, have been found at
levels above the recommended
standard in some supplies. The
elimination of unsafe levels of THMs
is a priority and all such supplies have
been the subject of enforcement
action by the EPA. This is expected
to eliminate THM exceedances
completely by 2014. There were also
a small number of drinking water
samples that exceeded nitrate and
lead standards in 2010. In all such
cases the risk to human health was
minimal (EPA, 2011a).
Waste Water
Sewage and other waste waters
contain microbiological and chemical
substances that can harm health.
Significant investment has gone
into improving the water services
infrastructure over the past decade,
which has resulted in a dramatic
improvement in the effectiveness
of treatment of urban waste water.
Despite these advances, sewage
discharges comprise the main
municipal pollution source of water
and continue to pose a threat to
human health and the environment
in many areas (EPA, 2010). Pollution
from municipal waste water
treatment plants may arise where
there is inadequate treatment,
combined storm water overflows
operating incorrectly or direct
untreated discharges. Since 2007,
local authorities are obliged to obtain
a Waste Water Discharge Licence
or Certificate of Authorisation
from the EPA. The authorisation
process provides for the EPA to place
conditions on the operation of such
discharges to ensure that potential
effects on the receiving water bodies
are strictly limited and controlled.
In rural areas most people use
individual septic tanks that, if poorly
sited and/or not properly maintained,
can pollute groundwater, surface
water and local drinking water
supplies. In 2012 the Department
of Environment, Community and
Local Government published the
Water Services (Amendment) Act to
regulate wastewater discharges from
all homes that are not connected
to the public sewer network.
Implementation and enforcement
by local authorities and the EPA of
this legislation regulating septic tanks
will reduce the potential threat to
public health.
Figure 9.2
Number of Public Water Supplies in which
E. coli
Was Detected in Compliance Monitoring at Least Once
from 2004 to 2010 (Source: EPA)
0
10
20
30
40
50
60
70
80
90
100
2010
2009
2008
2007
2006
2005
2004
No. of Public Water Supplies