Except as may be approved by the Zoning Administrator, and except for a governmental agency for the purpose of screening, no wall, fence, structure, tree, shrub, vegetation, or other obstruction shall be placed on or extend into a yard or right-of-way area so as to pose a danger to traffic by obscuring the view of approaching vehicular traffic or pedestrians from any street or driveway. Visibility from any street or driveway shall be unobstructed above a height of 3 feet, measured from where both street or driveway centerlines intersect within the triangle described as beginning at the intersection of the projected curb line of 2 intersecting streets or drives, thence 45 feet along one curb line, thence diagonally to a point 45 feet from the point of beginning along the other curb line. The exception to this requirement shall be where there is a tree, planting, or landscape arrangement within such area that will not create a total obstruction wider than 3 feet. These requirements shall not apply to conditions of this title that legally exist prior to June 7, 2011, unless the Zoning Administrator determines that such conditions constitute a safety hazard.