The Department of Public Works shall designate a standard type street name or number sign for all private streets, courts or ways within the City which shall be readily distinguishable from street signs identifying public streets. It shall be the responsibility and financial obligation of the developer to provide and maintain such private street signs; and furthermore, building permits shall not be issued until the applicable signs have been erected at appropriate locations as designated by the Department of Public Works. (Code 1981 § 40-236. Code 1995 § 130-499.)