Physico-chemical characteristics and pollution levels of heavy metals in Jajrood River, East of Tehran, Iran

For pollution prevention and reduction onto a river system, study of physico-chemical properties and its pollutant situation is necessary. Jajrood River is one of the important rivers that is located in the province of Tehran (capital of Iran). This research has been carried out to determine the water quality, pollutant situation, heavy metals of Jajrood River, and comparison of the results with global standards. For predicting of protection and reduction of this river system, we sampled from 7 stations along the main branch Jajrood River, and 3 stations in the minor branches monthly from April 2003 to August 2004. In water samples, pH,EC,DO,BOD,COD, some cations and anions, and heavy metals determined in tab. The results indicated that in the each agricultural, industrial, and human affected region, the properties have variations especially in low-water regimes. Heavy metals concentrations in the stations along main branch are insignificant. But the minor branches stations are polluted by heavy metals because of industrial, municipal, and agricultural wastewater and transport for recreation and building works. The minor branches need to environmental monitoring and mitigation measure. The results showed that in minor branches dissolved oxygen of river has reduced and BOD has increased. Continuing of determination of water quality in the minor branches of Jajrood must be a water pollution control plan. We suggest treatment plans for industrial factories of around the river. Improve monitoring of the surface water discharge to river, to limit building of around river and to limit transport around the river.