Date of Award
1-1-2007
Document Type
Thesis - ECU Access Only
Publisher
Edith Cowan University
Degree Name
Master of Science
School
School of Natural Sciences
Faculty
Faculty of Computing, Health and Science
First Supervisor
Mark Lund
Abstract
Stormwater is recognised as a transport mechanism for pollutants. Pollutants enter stormwater drains via surface washoff, subsurface flow or direct discharge. Landuse is reported to affect the quantity of pollutants released into stormwater drains. In Australia, the contribution of nutrients (nitrogen and phosphorus) and surfactants from industrial areas to surface drainage is poorly understood. Previous research has mainly focused on the quality of water leaving residential and agricultural areas. In Western Australia, there is growing concern over the health of the Swan-Canning River system, which is seeing signs of eutrophication. Runoff and discharge from residential, commercial, and industrial areas influence the quality of water in the Swan-Canning River system.
A study of nutrient release was undertaken for the eastern sector of the Canning Vale Industrial Area, to determine the contribution of industry to nutrient loads received by the Canning River system, between August 2001 and 2002. Data was collected three times a week using a point sampling regime. Diurnal and storm event variability were also tested. Data collected from the eastern sector of the industrial area was compared to that released from the entire Bannister Creek Catchment area.
Nitrogen and phosphorus concentrations downstream of industrial areas have been reported at 45mg L-1 and 15mg L-1 respectively (Thomas et al, 1997; John, 2000). In this study, the median concentrations of nitrogen and phosphorus downstream of industry in Bannister Creek, at the Tom Bateman Reserve Detention Basin, were 1.32mg L-1 and 0.11mg L-1 respectively. Concentrations of nitrogen and phosphorus were not indicative of point source discharge. Nutrient concentrations reported in Bannister Creek in this study, have been consistent with data collected and reported in other studies i.e. Donohue et al, 1992 and Jakowyna, 2002.
Nitrogen and phosphorus loads released from the entire Bannister Creek Catchment area, exceeded loads previously reported in other studies i.e. Donohue et al ( 1994); Donohue et al, 1992 and Jakowyna, 2002. An estimated 32890kg of nitrogen and 2085kg of phosphorus was released from Bannister Creek Catchment during the study. Rainfall during the study period was reflective of the drying climate Perth has been experiencing over the last ten years. Nitrogen and phosphorus released from Bannister Creek during the study period are likely to be underestimated, as they do not include the data collected for a significant storm event recorded at Hybanthus Road on the 16.4.02. During this 1- 2/1-5 ARI storm event 1586kg of nitrogen and 185kg of phosphorus were exported from Bannister Creek, producing loads ten times greater than that estimated during the point sampling regime. The later values were used in the calculation of annual loads to maintain consistency between the study sites. Despite the significant load of nutrients released from the catchment on 16.4.02, rainfall was not the main transport mechanism for nitrogen and phosphorus, indicated by the weak correlation e.g. R2 > 0.1. Base flow was determined to be the most significant pathway of nutrient export.
The concentrations and loads of nitrogen and phosphorus released from the industrial area were low, but the contribution to catchment loading was important. The rate of nutrient release per unit of area was higher from the eastern sector of the Canning Vale Industrial Area than the entire Bannister Creek Catchment Area. Nitrogen was released at a rate of 4163kg km2 yr from the industrial area and 134 2. 86kg km2 yr for the entire catchment. Phosphorus was the same. From the industrial area it was released at a rate of 397kg km2 yr compared to a rate of 94.2kg km2 yr from the entire Bannister Creek Catchment Area.
The study revealed the need to retain nutrients within the catchment. Studies on stormwater management suggest that this can be achieved through Water Sensitive Urban Design and Best Management Practices. Both strategies work on the principle of retaining and recycling nutrients within the catchment area. Work is currently been undertaken to meet the objectives of these two management strategies in Bannister Creek. Work has included the removal of the southwestern bank of the Tom Bateman reserve detention basin to create a meandering wetland, and the downgrading of the banks along Bywood Way, Lynwood to create a Living Stream. Further studies should focus on the effectiveness of these strategies.
Recommended Citation
Hall, S. (2007). The contribution of heavy industry and commercial activity at Canning Vale to the loads of nitrogen and phosphorus released in the Bannister Creek catchment area. Edith Cowan University. Retrieved from https://ro.ecu.edu.au/theses/307