Understanding future water quality risks under low and variable water level conditions

Understanding future water quality risks under low and variable water level conditions

There is potential for water quality to be impacted by lower and more variable water levels in dams and reservoirs. Importantly, there is some evidence that recovery of water quality from extremely low water levels may not occur or may at least be delayed.


Symptoms of poor water quality relate to increased occurrence of cyanobacteria (=blue-green algae) blooms, and particulate (e.g. inorganic sediment) and dissolved organic matter, including taste and odour producing compounds, as well as increased potential for short-circuiting of pathogens and other contaminants from inflows to dam and reservoir offtakes.

This project will develop a comprehensive understanding of water quality impacts from low and variable water levels. The project will include five main components:

  1. Comprehensive review of low water levels on dam and reservoir water quality.
  2. Developing theory to underpin, and to propose a conceptual model to help guide utilities in assessing the likely effects of low water levels and selecting suitable mitigation actions.
  3. Validate the conceptual models developed in (2) through sensitivity analysis.
  4. Use of the conceptual framework (from (2)) and model sensitivity analysis (from (3)) to identify parameters that have greatest uncertainty and the processes that are poorly represented in the models.
  5. Development of a risk assessment tool which may include use of alert levels (e.g. based on water levels or rate of water level change) to help inform management, including implementation of water restrictions and necessity to adjust water treatment processes. A Bayesian Network will be used in the risk assessment and to characterise some of the uncertainties around water quality predictions.


WaterRA Contact

Dr Kelly Hill | Research Manager 

Amount being sought


Due Date

28th Feb, 2020