For any site alteration, development, or enlargement on a zoning lot which contains designated open space, the City Planning Commission shall certify whether or not the applicant shall be required to provide a public pedestrian way through a portion of the designated open space.

When a public pedestrian way is required, it shall be built and maintained by the owner of the zoning lot and shall be accessible to the public at all times. The public pedestrian way shall be improved at the time the site alteration, enlargement, or development takes place.

The location and dimension of such pedestrian way shall be determined by the Commission. The owner of the zoning lot may request the City to take an easement on the property. If the City of New York acquires an easement for public access to any designated open space on which a building has been, is being or could be in the future, constructed in accordance with the provisions of this Chapter, the City's acquisition of an easement shall not affect the qualifications of the designated open space requirements as provided in Section 107-224 (Qualification of designated open space as lot area for bulk computations) and shall not be deemed to create a non-compliance.