Optical Remote Sensing in the Water Column

The Challenge

Water quality is a critical factor in preserving economically and environmentally healthy waterways. Occurrences such as algal blooms and fish death events cause considerable impact to human and ecosystem health, and monetary impact to the agricultural economy.

Restoring and maintaining healthy ecosystems, predicting algal blooms and addressing contemporary problems such as fish deaths and cold-water pollution requires data about subsurface water temperature, salinity, dissolved oxygen, and pigments such as chlorophyll and phycocyanin.

All current sub-surface measurement technologies require a measurement instrument to be lowered into the water. When these instruments are submerged, as is the case with current dissolved oxygen sensors, and the equipment must remain in situ, then these instruments suffer from biofouling and are typically incapable of providing useful data after a couple of weeks.

Furthermore, current practices for detecting cyanobacteria (as an indicator of algal blooms) require up to 10 days to retrieve a sample from a water storage (such a dam or reservoir) have it returned and tested in a lab.

The Solution

Working with NSW Department of Industry, Environment, and Planning (DPIE), researchers from Macquarie University and the University of Technology Sydney (UTS) are evaluating optical sensing methods for systematic mapping of a range of parameters in natural waterways. 

The laser-based technology developed by the team will be non-contact, and will generate data in near-real time, overcoming some disadvantages of the existing technologies such as biofouling of probes and long retrieval and analysis times.

University partners: