Characterising material transport from Swan River Sediments

Characterising materials transport from Swan River sediments

Supervisors

• Marco Ghisalberti
  Senior Lecturer, Oceans Graduate School

• Maryam Abdolahpour
  Research Fellow, Civil, Environmental and Mining Engineering

Students

• Kaleb Jaschke
• Benjamin Davidson

Project Description

This project addresses a fundamental, unanswered question in our efforts to sustainably manage water quality in the Swan River: "How important are the sediments?". Aquatic sediments can represent a predominant source (or in some cases, a sink) of nutrients, contaminants and oxygen demand for the water column. However, our inability to quantify the interaction between the sediments and overlying (and highly dynamic) water column remains a critical barrier to improved modelling and management of water quality in the river.

This project utilises a novel experimental methodology, Refractive Index Matching, to allow measurement of material transport at all locations across the sediment-water interface for realistic sediment bed morphologies. This will allow vertical transfer rates (of, e.g., nutrients) to be quantified directly as functions of flow and bed characteristics. The contribution of sediments to sustaining nutrient pollution in the river, and its variability in space & time (to understand hot spots & danger periods) will be determined.

Through this state-of-the-art experimental program, we will gain a fundamental understanding of flow-driven vertical transport at the sediment-water interface in the Swan River, focusing on the impact of realistic sediment bed composition and form. The key outcome will be a “water-column- to-bedrock” description of vertical transport in Swan River sediments, which can be readily extrapolated to other Australian river systems.