Chichester Dam – determining limiting nutrients to phytoplankton growth and the role of nutrients released from sediments

Project Member(s): Mitrovic, S., Facey, J.

Funding or Partner Organisation: Hunter Water Corporation (Hunter Water)
Hunter Water Corporation (Hunter Water)

Start year: 2022

Summary: This project proposal and quote has been requested by Hunter Water corporation. The work program will achieve the objectives presented below. • Seasonal microcosm experiments will be undertaken at the dam to determine which nutrients limit the growth of the phytoplankton community (as chlorophyll a) and as different algal genera or species (where potentially toxic or problematic species occur). Three sites will be examined including near dam wall, mid dam and upper dam. • Two longer term mescosm experiments (month long) will be performed at one site to determine the longer-term response to nutrients. These will be done during summer or periods of higher algal / cyanobacterial growth. • Sediment nutrient release experiments will be performed at UTS with sediments collected from the 3 sites used for the nutrient limitation work. These will be performed during 2 seasons (summer and winter) and experiments will examine nutrient release under oxic and anoxic conditions. • Nutrient concentrations in the epilimnion and hypolimnion will be measured at the three sites seasonally for 2 years. Also inflowing and outflowing nutrients will be measured to better understand the nutrient budget of the dam. • A report will be completed at the end of the study indicating the limiting nutrients to Chichester Dam, the role of sediments in releasing nutrients and management recommendations for management of the dam in terms of nutrients.

FOR Codes: Environmental management, Ecosystem Assessment and Management of Fresh, Ground and Surface Water Environments, Assessment and management of freshwater ecosystems