The following regulations shall also apply in R-S districts:

    A.    The width of access driveways shall be not less than that required by Section 17.52.790; provided however, that the commission may require a driveway of greater width, or provision for a street where found necessary to assure adequate circulation in the vicinity;

    B.    The minimum setback from the access driveway shall be as required by Section 17.52.800;

    C.    There shall be effective structural or landscape screening of private and utility areas, and a system of walkways, independent of the driveways to give safe pedestrian access from the street to every dwelling unit and to all commonly utilized open spaces;

    D.    The area of useable open space provided on the site, calculated pursuant to prior code Section 8-60.51, shall be not less than six hundred (600) square feet for each dwelling unit thereon. (Prior gen. code § 8-28.11)