A new lot shall be only be allowed if it will abut a public street, or a private street or parking court that the City approves as meeting such purpose after a review by the City Law Department and Department of Public Works. A new apartment building or commercial or industrial building shall not be constructed unless it is on a lot that is adjacent to such a street or approved parking court. An alley with a cartway width of less than 16 feet or a right-of-way width of less than 20 feet shall not, by itself, be used to meet the requirements of this section.