Water resources are also largely used for agricultural irrigation
Water resources are also largely used for agricultural irrigation (Howell et al., 2001). It has been estimated by the United Nation World Water Development Report (UNWWDR 2003) that about 70% of the global freshwater is used for agriculture purpose. Agricultural processes involving the use of fertilizers, herbicides, and pesticides produce toxic substances that are transported as effluents into water sources, and these pollute water bodies (Obi et al, 2007). So after water usage for different purposes it possesses a large amount of contaminant, which results in changing the physicochemical properties of water, add heavy metals to the water and receive different major concern considering their strong toxicity even at low concentrations (Marcovecchio et al., 2007). Water pollution is one of the severe global problem, which requires ongoing evaluation and revision of water resource policy at all levels. Along with other contaminants the heavy metals discharged by industries, traffic, municipal wastes and other domestic activities can result in a steady rise in contamination of water reservoirs throughout the world (Vodela et al., 1997).
Mardan is a densely populated area in KpK (Pakistan). According to census 2017 the total population of District Mardan is 2373061. Out of total population the population of rural citizen are 1933736 and 439325 are located in urban area. And the average annual growth rate is 2.58 from 1998 to 2017. In order to meet the needs of ever increasing population growth rate it become an industrialized area, the traffic use increase and also the use of water for irrigation and household activities increase. In Mardan, Kalpani Nalla is the main Nalla in which the wastewater from industries, agricultural, and domestic activates is released. Due to all these contamination sources the Kalpani Nalla is polluted day by day. No intensive study has been conducted on this Nalla so far because in this research we will investigate the variation of the
selected water parameters and E-coli bacteria concentration during two different seasons in surface water of the Kalpani Nalla. As this Nalla receives water from multiple sources so due to ever increasing anthropogenic activities this is to be considered as dirtiest Nalla of KPK (KPK 2007).