All residences in a PRD shall be directly served by a system of walkways or sidewalks for pedestrian circulation within the development and between the development and surrounding areas. Such system may include sidewalks within public street rights of way or independent walkways. Sidewalks along only one (1) side of a street shall be permitted in those instances where ten (10) or fewer dwelling units derive access from the street or have frontage thereon. (Ord. 7139-99. Passed 7-6-99.)