There has been growing concern, in the past decades, about the deterioration of water quality and the marine environment in Gulf St Vincent. This has led to a number of long-term studies investigating the causes and effects of pollution from metropolitan and rural sources.

It is now understood that wastewater, industrial discharges and stormwater carrying pollutants (particularly nutrients) are the major culprit in the extensive loss of seagrasses (and their associated marine life) off Adelaide and other coastal regions.

Secchi Disk Monitoring is operated by volunteers and coordinated by the Friends of Gulf St Vincent based in Adelaide, South Australia.

The Secchi Project provides a baseline and record of trends, and helps to educate about the sources and impacts of pollution.

The Secchi Disk is a relatively simple and inexpensive way to measure water clarity – the black and white disc is lowered into the water until it is no longer visible. This distance is the ‘Secchi Depth’.