title: Urban stormwater inputs to an adapted coastal wetland: role in water treatment and impacts on wetland biota.
abstract: The Lake Pertobe wetland system is a semi-natural wetland that has been modified primarily for recreational use. However, this lake system receives stormwater from much of the central business district of Warrnambool City (Victoria, Australia) and serves as a buffer zone between the stormwater system and the Merri River and Merri Marine Sanctuary. This work considers the impact of stormwater inputs on Lake Pertobe and the effectiveness of the lake in protecting the associated marine sanctuary. Sediment contaminants (including heavy metals and polycyclic aromatic hydrocarbons (PAHs)) and water quality parameters within the lake, groundwater and stormwater system were measured. Water quality parameters were highly variable between stormwater drains and rain events. Suspended solids rapidly settled along open drains and shortly after entering the lake. Groundwater inputs increased both salinity and dissolved nitrogen in some stormwater drains. Some evidence of bioaccumulation of metals in the food chain was identified and sediment concentrations of several PAHs were very high. The lake acted as a sink for PAHs and some metals and reductions in Escherichia coli, biological oxygen demand and total phosphorus were observed, affording some protection to the associated marine sanctuary. Nutrient retention was inadequate overall and it was identified that managing the lake primarily as a recreational facility impacted on the effectiveness of stormwater treatment in the system.
authors.affiliation: Center for Integrated Ecology, School of Life and Environmental Sciences, Deakin University, PO Box 423, Warrnambool, VIC 3280, Australia; Institute for Land Water and Society, and School of Agricultural and Wine Sciences, Charles Sturt University, Locked Bag 588, Wagga Wagga, NSW 2678, Australia. Electronic address: jhowitt@csu.edu.au.
authors.forename: Julia A
authors.initials: JA
authors.lastname: Howitt
authors.affiliation: Center for Integrated Ecology, School of Life and Environmental Sciences, Deakin University, PO Box 423, Warrnambool, VIC 3280, Australia.
authors.forename: Julie
authors.initials: J
authors.lastname: Mondon
authors.affiliation: Center for Integrated Ecology, School of Life and Environmental Sciences, Deakin University, PO Box 423, Warrnambool, VIC 3280, Australia.
authors.forename: Bradley D
authors.initials: BD
authors.lastname: Mitchell
authors.affiliation: Center for Integrated Ecology, School of Life and Environmental Sciences, Deakin University, PO Box 423, Warrnambool, VIC 3280, Australia.
authors.forename: Toby
authors.initials: T
authors.lastname: Kidd
authors.affiliation: Center for Integrated Ecology, School of Life and Environmental Sciences, Deakin University, PO Box 423, Warrnambool, VIC 3280, Australia.
authors.forename: Bruce
authors.initials: B
authors.lastname: Eshelman
mesh_terms: D001315:Australia; D002947:Cities; D004784:Environmental Monitoring; D019216:Metals, Heavy / Q000032:analysis; D009584:Nitrogen / Q000032:analysis; D010758:Phosphorus / Q000032:analysis; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis*; D011891:Rain; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000032:analysis; D053833:Wetlands
chemical_list: D019216:Metals, Heavy; D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical; D010758:Phosphorus; D009584:Nitrogen
keywords: Bioaccumulation; Constructed wetland; Heavy metals; Nutrients; PAH; Sediments