Investigation of urban water quality using simulated rainfall in a medium size city of China
- 236 Downloads
Road-deposited sediment (RDS) is an important environmental medium for impacting the characteristics of pollutants in stormwater runoff; it is of critical importance to investigate the water quality of urban environments. The paper develops a rainfall simulator as an important research tool to ensure homogeneity and reduce the large number of variables that are usually inherent to urban water quality research. The rainfall simulator was used to experiment runoff samples from typical residential and traffic areas in the Zhenjiang. The data show that land use is one of the major factors contributing to the difference in the pollutants concentration in the RDS. The maximum mean EMC for TN, TDN, TP, and TDP at residential area was 5.52, 3.07, 1.65, and 0.36 mg/L, respectively. The intense traffic area displayed the highest metal concentrations. Concentrations of runoff pollutants varied greatly with land use and storm characteristics. The correlation of pollutant concentrations with runoff times was another predominant phenomenon. Peaks in pollutants concentration occurred at 1 and 10 min during the whole storm event. A concentration peak that correlates with a peak in runoff flowrate correlates with rainfall intensity. The pollutant loadings (kilograms per hectare) in the Zhenjiang were 11.39 and 55.28 for COD, 8.42 and 57.48 for SS, 0.11 and 0.88 for TN, 0.02 and 0.14 for TP, 0.02 and 0.09 for Zn, and 0.01 and 0.04 for Pb. The higher rainfall contribute to the higher pollutant loading at the residential and intense traffic areas, as a result of the pollutant loadings direct dependence on rainfall intensity. The results confirmed that the rainfall simulator is a reliable tool for urban water quality research and can be used to simulate pollutant wash-off. These findings provide invaluable information for the development of appropriate management strategies to decrease nonpoint source contamination loading to the water environment in urban areas.
KeywordsRain simulation Event mean concentration Urban water quality Land use Pollutant loading
Unable to display preview. Download preview PDF.
- APHA (1999). Standard methods for the examination of water and wastewater. Washington: American Public Health Association, American Water Works Association, Water Environment Federation.Google Scholar
- Buffleben, M. S., Zayeed, K., Kimbrough, D., Stenstrom, M. K., & Suffet, I. H. (2002). Evaluation of urban non-point source runoff of hazardous metals entering Santa Monica Bay, California. Water Science Technology, 45, 263–268.Google Scholar
- CGL, China Geological Laboratory (1987). Analytical method and quality management for samples of 1:200 000 geochemical exploration (pp. 50–61). Beijing: China Geology Press.Google Scholar
- Droppo, L. G., Irvine, K. N., Murphy, T. P., & Jaskot, C. (1998). Fractionated metals in street dust of a mixed land use sewershed, Hamilton, Ontario. In Hydrology in a changing environment (Volume III, pp. 383–394). British Hydrological Society.Google Scholar
- Ellis, J. B., & Revitt, D. M. (1982). Incidence of heavy metals in street surface sediments: Solubility and grain size studies. Water, Air and Soil Pollution, 17, 87–100.Google Scholar
- Lee, J. H., Bang, K. W., Ketchum, L. H., Choe, J. S., & Yu, M. J. (2002). First flush analysis of urban storm runoff. The Science of the Total Environment, 293(1–3), 163–175.Google Scholar
- Lu, R. K. (1999). Analysis methods of soil agricultural chemistry (pp. 228–233). Beijing: China Agricultural Science and Technology Press.Google Scholar
- Vaze, J., & Chiew, F. H. S. (1997). A field study to investigate the effect of raindrop impact energy and overland flow shear stress on pollutant wash-off. Urban stormwater pollution. (pp. 255–264). Melbourne, Victoria: Cooperative Research Centre for Catchment Hydrology.Google Scholar