Understanding spatiotemporal variability of in-stream water quality in urban environments - A case study of Melbourne, Australia

JOURNAL OF ENVIRONMENTAL MANAGEMENT

卷:246

Article

Shi, Baiqian¹  Bach, Peter M.^2,3,4  Lintern, Anna^1,2  Zhang, Kefeng⁵  Coleman, Rhys A.⁶  Metzeling, Leon⁷  McCarthy, David T.¹  Deletic, Ana⁵ 

[1] Monash Univ, Dept Civil Engn, Environm & Publ Hlth Microbiol Lab, Wellington Rd, Clayton, Vic 3800, Australia

[2] Monash Univ, Dept Civil Engn, Wellington Rd, Clayton, Vic 3800, Australia

[3] Swiss Fed Inst Aquat Sci & Technol Eawag, Uberlandstr 133, CH-8600 Dubendorf, Switzerland

[4] Swiss Fed Inst Technol, Inst Environm Engn, CH-8093 Zurich, Switzerland

[5] Univ New South Wales, UNSW Water Res Ctr, Sch Civil & Environm Engn, Sydney, NSW 2052, Australia

[6] Melbourne Water Corp, La Trobe St, Docklands, Vic 3008, Australia

[7] Environm Protect Author, Macleod, Vic 3085, Australia

关键词: Urban water quality;    Land uses;    Imperviousness;    Urban development;    Environmental management;    Pollution sources;   

DOI  :  10.1016/j.jenvman.2019.06.006

来源: Elsevier

【 摘 要 】

To support sustainable urban planning and the design of water pollution mitigation strategies, the spatial and temporal trends of water quality in urban streams needs to be further understood. This study analyses over ten years of surface water quality data from 53 upstream catchments (20 of them predominated by a single type of land use) and two lowland sites across Greater Melbourne, Australia. We evaluated the impact of various catchment characteristics, especially urban land uses, on spatial and temporal urban water quality trends. Here, we focused on common urban pollutants: total suspended solids (TSS), total phosphorous (TP), total nitrogen (TN), zinc (Zn), copper (Cu) and nickel (Ni). Site median nutrient and heavy metal concentrations were negatively correlated with the catchment's elevation and its average annual rainfall. Further analysis shows that such trends were driven by the geographical pattern of Melbourne - i.e. low-laying sites tend to have less rainfall and be more urbanised. Only median concentrations of heavy metals (Zn and Cu) were correlated to catchment imperviousness. Further characterising of the urban environment was done into specific land uses (residential, industrial and commercial), yet median concentrations of all pollutants were not significantly correlated with land uses. This is because simple metrics, such as land use proportions, do not adequately reflect the significant variability in pollution sources that can exist even within the same land use type. Indeed, our temporal analysis found that the water quality difference between catchments with similar land uses is likely caused by their sitespecific pollutant sources (construction and illegal discharge) and environmental management actions (wastewater management actions) regardless of similarities in land use. A 3-stage urbanisation cycle (development, operation and renewal) is suggested to further explain the urban water quality variance, but more data from small areas of an urban catchment is required to directly understand the unique impact of each urbanisation stage on water quality.

【 授权许可】

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