No use or structure, including parking or loading areas, shall be permitted within the required buffer area, but the Planning Board may, upon a finding of reasons therefor, permit a portion of a buffer area to be used for utility easements or streets to ensure access to or from adjacent property, and the Board may also permit a portion of a buffer area to be used for a detention or retention basin, provided that the basin is designed as a landscaping feature, and further provided that the landscaping plan for the buffer area is determined by the Planning Board to meet the objective of a buffer area.