Wherever the topography and vegetation are to be disturbed, a plan for the control or erosion and sediment and grading is required. It shall be unlawful to pave, fill, strip or change the existing grade of any land; and it shall be unlawful to disturb, modify, divert, block or affect the natural overland or subsurface flow of stormwater within the Township without first securing a zoning permit. No permits shall be required for normal agricultural operations or where the area to be stripped does not exceed 1,000 square feet and where the grade change does not exceed six inches in any one area and all bare earth is properly seeded, sodded or otherwise protected from erosion.