The Regional Catchment Strategy for the Port Phillip & Western Port region
Current Condition (Port Phillip Bay)

Current condition of marine water quality in Port Phillip Bay

The marine water quality in Port Phillip Bay is generally good and meets most of the State Environment Protection Policy objectives on most occasions.  A summary of the recent water quality monitoring for some important parameters is shown in the table below.

Summary of the attainment of SEPP objectives in Port Phillip Bay (2011)

Water quality parameters Number of parameters measured Number of samples meeting SEPP objectives SEPP attainment percentage
Secci disc depth 100 83 83%
Dissolved oxygen 82 78 95%
Chlorohphyll 136 114 84%
Arsenic 78 77 99%
Chromium 78 78 100%
Cadmium 50 50 100%
Zinc 78 78 100%
Total 602 558 93%


Whilst the water quality is generally good, water samples sometimes fail SEPP objectives for turbidity (secci disc depth), chlorophyll and dissolved oxygen.  Turbidity is an important parameter to monitor because high turbidity reduces light penetration and hampers the ability of seagrass and mangrove communities to flourish.

This assessment of the condition of marine water quality is used as the basis for setting targets for the future (Targets). Lead organisations are committed to achieving these targets (Leadership) and arrangements are in place to monitor and report on progress and success (Monitoring and Reporting).