[Amended 4-1-1985 by L.L. No. 5-1985]
On a lot in the Office Building OB District, accessory off-street underground parking structures may project above the adjacent grade, provided that such above-grade projection does not intrude into any required front yard, nor into any required planting or landscape area; nor shall such projection when facing any street front be higher than three feet above the mean grade established by the average of the grades at each end of the frontage on such street; nor shall the length of such projection exceed 20% of the total length of the building along such street front. Notwithstanding the definition of "yard," the partially underground parking structure may intrude above grade into the required side and rear yards, provided that the roof deck of the garage structure is not higher than seven feet above the grade of any contiguous property. If the parking structure is totally below grade, it may extend to all property lines, provided that a minimum depth of 2 1/2 feet of earth for planting exists over such a structure within the required landscaped or planting area. In no case shall any part of the parking structure extend beyond the Office Building OB District boundary line into any other district.