Whitianga Outfall - Viral Fate
The wastewater treatment plant at Whitianga was upgraded.
The wastewater treatment plant at Whitianga was upgraded in 2009. The downstream fate of discharge water during a variety of weather conditions and release strategies was simulated. Numerical simulations, including sensitivity testing with respect to release timing, wind conditions, tidal state, and season (for viral decay rates), were designed to track the evolution of discharged viral loads within the estuary and focussed on key locations such as oyster farms, priority bathing beaches, and areas with low flushing.
Various release strategies were tested to minimise downstream concentrations. An intermittent release strategy, timed to coincide with the full to outgoing tide, was shown to have the least impact on commercial oyster beds and bathing beaches. Releases during southwest wind revealed a potential for increased viral concentrations entering the waterways cannel development.
