On streets where parking is limited in time, the Police Department, at the direction of Council, shall cause parking spaces, approximately twenty feet in length, to be marked by lines on the curb or pavement or by other appropriate markings and on the sidewalk adjacent to each such parking space or at such other place as Council may direct, cause to be erected a parking meter, which, upon the deposit of a coin as hereinafter provided, will indicate the duration of the legal parking period and the time when such period has elapsed. (1976 Code Sec. 18-176)