Irrigation with sewage water: Assessment of water quality, nutrients and heavy metal distribution

Abstract

Study was conducted to examine quality, distribution of nutrients and heavy metals in sewage water used for irrigation in and around of Quetta city, Pakistan. Water samples were collected from three main sewage drains (Habib nala, Ispini and Sabzal Road). Collected water samples were analyzed for EC, SAR, RSC, Cl-, SO4++, Ca++ + Mg ++, Na+, K+, P, Fe++, Mn, Zn, Cu, Pb and Ni. Results revealed that the EC was 9.96 ds m-1 for Ispini road drain. and overall range of SAR were 33.50 Habib nala, 19.16 Subzal road and 18.21 for Ispini road. The pH of sewage water varied from 7.24 to 9.21. The concentration of essential nutrients (macro+ micro) and toxic metals varied greatly in samples between locations. The concentration of P and K+ was high (1.18 ppm and 0.81 me L-1) in Habib nala than Ispini and Subzal road sewage drain. The concentration of micro nutrients (Fe++, Mn, Zn, Cu) were with permissible limits. With respect to toxic metals, Pb was generally greater (0.12ppm) in Ispini road drain compared with (0.05-0.08 ppm) in other sewage drains. The minimum and maximum Ni (0.09 and 0.18 ppm) was found in Ispini and Subzal road drain. © 2006 Asian Network for Scientific information.