Turbidity is a measure of the cloudiness in water caused by suspended material. During the project, this will be managed throughout the project using an adaptive management approach and real-time monitoring.
Turbidity is measured in Nephelometric Turbidity Units (NTU). Should the nominated NTU limits set by the EPA be exceeded, the dredge contractor will take action and either adjust or cease dredging. The limits and actions are summarised below
Turbidity monitoring data – updated every hour
The line graphs show the median level of turbidity recorded by each monitoring buoy, calculated over a rolling 6 day and 15 day median. If turbidity increases due to dredging activities, the D1 and D2 lines on the graph will rise.
If turbidity has increased due to background conditions unrelated to dredging, for example, due to a storm or weather event, B1 will rise on the graph. If B1 rises, D1 and D2 may naturally rise too and follow a similar line. Remember to refresh your browser to make sure that you have the most current data. Please note that the Turbidity Monitoring Data is best viewed on a desktop computer.
Dredging commenced on the 7th of June. It can be noted that there was a rise in turbidity levels prior to dredging commencement due to weather events in the week of the 27th of May. You can see that prior to the commencement of dredging, the background monitor (B1) reflected the same increase in turbidity as the monitoring locations D1 and D2.
The gauges show the results on the graph in another format. If turbidity reaches ALARM or HOLD, this will be clearly stated on the gauges. Remember to refresh your browser to make sure that you have the most current data.
Dredge plume monitoring site 1 (D1)
Dredge plume monitoring site 2 (D2)
Background monitoring location (B1)
6 Day Rolling Median
15 Day Rolling Median
The satellite imagery below is processed using algorithms to illustrate the turbidity plumes. Remember to refresh your browser to make sure that you have the most current data. Please note that the images below indicate cloud cover, shown as white/grey clouds in the MODIS True Colour image, and as black patches on the MODIS Derived NTU image. Turbidity is shown by the Turbidity Heat Map.