The subdivider shall construct all necessary facilities including underground pipe, inlets, catch basins, ditches or retention basins, as determined by the Municipal Engineer in accordance with the Storm Water Design Manual to provide for the adequate disposal of subsurface and surface water and maintenance of natural drainage courses. In cases of open drainage ditches, there shall be provided a storm water easement or drainage right of way of sufficient width to adequately handle potential maximum flows. Drainage ditches, wherever possible, should be constructed with landscaped banks. All storm drainage facilities within the subdivision shall connect to an adequate drainage outlet. Sound engineering practice considering local physical conditions or innovative techniques in variance with the Storm Water Design Manual may be acceptable if approved by the Municipal Engineer.