Research Topic :Mechanisms of cyanobacterial bloom formation in drinking water reservoirs

Research Team :Doblin (UTS), Burford (Griffith University), Turnbull, Whitchurch (UTS)

Zooplankton have a pivotal role in water reservoirs because they regulate algal growth, yet are often absent from water quality monitoring programs. This project will examine two competing hypotheses regarding the role of zooplankton in cyanobacterial bloom development: 1) zooplankton grazing activities regenerate nutrients that are sequestered by cyanobacteria (and made unavailable to other algae); and 2) zooplankton exert proportionally less grazing pressure on cyanobacteria compared to other algae. The project outcome will be a conceptual, then process-based model (built in conjunction with the South East Queensland Water Corporation) to predict the likelihood of cyanobacterial bloom formation in a given reservoir, significantly improving the management capacity for intervention and mitigation, with significant water treatment savings.

Research Topic:Development of pre-filtration techniques to reduce biofouling on reverse osmosis membranes involved in seawater desalination

Research Team: Hill, Doblin, Turnbull, Whitchurch and Ralph (UTS)

The NSW government, in response to persistently low reservoir water levels has commissioned a new desalination plant to help solve Sydney’s water crisis.

Desalination uses reverse osmosis (RO) technology to filter dissolved salts, suspended solids and other organic molecules from seawater to provide a continuous freshwater drinking supply. Current reverse osmosis membrane filters are susceptible to deterioration through membrane fouling, caused by an accumulation of organic matter, particularly including microorganism communities which form a ‘biofilm’ clogging or fouling the membrane.  The project will compare a range of pre-treatment filters, to identify the most efficient method for reducing RO membrane biofouling. The efficiency of the pre-filtration techniques will be assessed by analysing the content of the influent seawater and comparing it to the content of the effluent (following pre-filtration) water. Direct measures on the pre-filtration material will allow for further assessment of filtration effectiveness. This will involve analysis of micro-organism development on filters and RO membranes using sophisticated state-of-the-art live cell imaging and molecular techniques.

If you are interested in any of these projects contact Dr. Martina Doblin