2013 2014 2015 2016 2012 2013 2014 2015 2016 2012 2013 2014 2015 2016 2012 2013 2014 2015 2016 4,832 4,828 4,863 4,635 4,778 278,065 273,660 275,174 274,426 275,264 98.3% 98.3% 98.3% 98.3% 98.3% 4.96 5.02 4.79 4.73 5.24 69 Water Pollution Control Main tasks of water pollution control are managing existing equipment and building backup facilities to improve water quality, and improving rainwater drainage by monitoring and managing.