Unless more stringent regulations are required by site plan or subdivision approval, or by other provisions of this chapter, at the intersection of two or more streets, no hedge, fence, screening strip, wall or landscape improvement, structure nor any other obstruction to vision, between all points between thirty (30") inches and eighty-four (84") inches above the center line of the intersecting streets, other than a pole, post, tree trunk or similar vertical obstruction, not exceeding eighteen (18") inches in diameter, shall be permitted within the triangular clear sight area formed by lot right-of-way lines and the line which connects the sight points, determined from Exhibits 9-9A and 9-9B, Case A, B, C1 or C2,[1] as applicable, located on the cartway, curbline or pavement edge of each intersecting street.