Chhattisgarh's five river stretches have been put under “Priority Class V” of pollution parameters of Central Pollution Control Board (CPCB). The polluted stretches are in Hasdeo, Kelo, Kharun, Mahanadi and Sheonath rivers, informed Union Minister for Water Resources Nitin Gadkari in a written reply to MP Chhaya Verma in the Lok Sabha. The CPCB is monitoring 445 rivers in 29 States and six Union Territories in the country.There are 302 polluted river stretches on 275 rivers. Among the 302 polluted river stretches, 34 are in Priority Class I, 17 in Priority ClassII, 36 in Priority Class III, 57 in Priority Class IV and 158 are in Priority Class V, he informed. The Central Water Commission (CWC) is monitoring water quality of rivers at 429 key locations covering 11 major river basins in India. As per analysis of trace and toxic metal data for May 2014 to August 2017, out of 414 river water quality stations, water samples collected at 136 water quality stations are found within the permissible limit as far as toxic metals are concerned. Water quality at 57 stations was found beyond the permissible limit due to presence of two or more toxic metals, the Minister informed. There are 167 numbers of stations in the country where water was considered unfit for drinking purpose due to presence of iron concentration beyond permissible limit. Similarly, water was found unfit for drinking at 19 stations due to presence of cadmium, at four stations due to presence of copper, at nine stations due to presence of chromium, at nine stations due to presence of nickel and at 63 stations due to presence of lead contamination, he informed. Nevertheless, it was concluded that arsenic and zinc concentrations are found within the acceptable limits as per Bureau of Indian Standards (BIS) and no toxicity of arsenic and zinc in the river waters is observed during the study period. Further, as per the analysis of Biochemical Oxygen Demand (BOD) for 2012-17, most of the stretches of rivers are not fit for drinking as well as bathing with respect to BOD as per IS: 2296-1992, Gadkari informed. As per National Commission on Integrated Water Resources Development (NCIWRD) report, the total water availability of India received through precipitation is about 4000 Billion Cubic Meter (BCM) per annum. After evaporation, 1869 BCM water is available as natural runoff. Due to geological and other factors, the utilizable water availability is limited to 1137 BCM per annum comprising 690 BCM of surface water and 447 BCM of replenishable ground water, Gadkari informed. As per information provided by States on the online Integrated Management Information System (IMIS), as on July 26, 2018, out of 17.26 lakh rural habitations in the country, 79.48% of them are having the basic minimum service level of 40 liters per day of safe drinking water as per the guidelines of the National Rural Drinking Water Programme (NRDWP), the Minister informed. Pollution in rivers has been observed due to rapid urbanization, industrialization and discharge of untreated / partially treated municipal sewage from towns, he informed.