In our study, the highest concentration among all of metals was Pb with range of 0.0128 mg/L. This result was different from the finding reported by Cheung et al. [25] that Zn was the most amount in the river samples, however, they also pointed out that the process of urban storm runoff carrying the Pb deposits into the river water appears to elevate the concentrations of Pb. On the other hand, the atmospheric depositions such as automobile exhausts and gasoline containing Pb may be other major sources of Pb in the region. According to the results reported by Wong et al. [26], atmospheric depositions of Cu, Cr, Pb and Zn were serious on the surface environment in this region.
Compared with other riparian wetlands water, the water in our study is higher enriched by Cd, Cu, Ni, Pb and Zn [31]. It is the reason that the discharge of domestic wastewater resulted in the higher metal concentrations [25]. The concentrations of Cu in all of samples exceed the range from 0.0005 to 0.001 mg/L which is the normal Cu levels in uncontaminated fresh waters [35]. The elevated concentrations of Cu may be attributed to the enrichment of Cu in the suspended matter, as [15] pointed out that even at background Cu concentrations in the river suspended matter can release considerable amounts of dissolved Cu into river water.