Monitoring and data trend analysis has continued at Heron Park over the last 6 months, including storm monitoring data from 2 “summer” storm events being captured.
Already this research* has shown that 6 TONNES (or 2kg per square metre) of sediment (builder’s sand) ended up the drain when it ran off an open sandy area of 3000 square meters where no sediment controls were in place during a recent storm, when just 36mm of rain fell over 16 hours!
A laboratory analysis of stormwater samples has been completed and the emerging relationship between Total Suspended Solids (TSS) and turbidity has been analysed.
The City of Armadale generously provided a RTK GPS device and operator to assist the Masters student to complete channel survey work.
The University of Western Australia and the CRC for Water have confirmed funding for technical support for this research during 2018/2019 and the Communications Plan for the Sediment Research Project has been endorsed by the Sediment Task Force.
The UWA Masters student undertaking the Sediment Research Project moved to part-time study June-August and has since suspended studies until November 2018. The anticipated finalisation date for the SRP is now March 2019, however this is weather dependent as additional rainfall event are required to be captured to finalise results.
*1. Research is still underway and these are not final or accurate numbers. 2. A 36mm storm could have greatly varying profiles of storm intensities. ie most of it could fall in an hour or in 3 separate 20 minute periods or spread more evenly across the entire time. 3. The relationship between turbidity and TSS is still being assessed. 4. There is still a limited understanding of the dynamics of the erosion and deposition in the section of the channel to get a good estimate of the contribution of sediment from the construction site verses the channel. 5. Sediment discharge is very dependent on the size, duration and intensity of the storm event.