(a) The Planning and Zoning Commission shall not approve any subdivision having inadequate storm drainage or other physical drainage impairment as determined by the Village Engineer. In areas known to be subject to periodic floods, such drainage improvements shall be made as to satisfy the Village Engineer and the Manager in order that the health and welfare of the people will be protected.
(b) No natural drainage course shall be altered and no fill, buildings or structures shall be placed in it unless provisions are made for the flow of water in a manner satisfactory to the Village Engineer. An easement shall be provided on both sides of any existing important surface drainage course adequate for the purpose of protecting, widening, deepening, enclosing or otherwise improving such stream for drainage purposes.
(c) A master grade plan shall be prepared for all subdivisions and shall be presented to the Manager for review and approval by the Village Engineer. The grading plan shall show the existing topography, the proposed street grades and the proposed storm sewers with pipe sizes and grades. It shall also show the proposed and shall delineate the method of rear yard drainage by showing proposed scales and direction of surface slope by arrows. The grading plan shall follow the standards as established for such grading by the Federal Housing Administration.
(d) Wherever possible, with exceptions being made where the topography of an area does not permit such grading practice, lots shall be graded from the rear lot line to the street. Where a lot abuts directly on two streets, the grade shall be from the corner of the lot which is diagonally opposite to the corner of the two streets on which the lot abuts. This section is included in order to reduce the amount of water standing in yards to a minimum. Therefore, where it is not possible to grade a lot in the prescribed manner, the owner or developer shall provide for the adequate drainage of any and all low areas and tie such drainage into and make it a part of the storm sewer system, the development and the Village as directed by the Village Engineer with approval of such drainage subject to inspection by the Village Engineer along with the inspection of other storm sewer installations.