The following requirements shall apply to special street types:
(a) Permanent dead-end streets shall not be permitted. Temporary dead-end streets shall be permitted only as part of a continuing street plan, and only if a temporary turnaround satisfactory to the Planning Commission in design, is provided, and provisions for maintenance and removal are advanced. Temporary dead-end streets longer than 200 feet shall not be permitted.
(b) Dedication of new half-streets shall not be permitted. Where a dedicated or platted half-street exists adjacent to the tract being subdivided, the other half shall be platted.
(c) Where a subdivision adjoins an arterial street, a marginal access street shall be designed, if the subdivision design is such that residential lots would require direct vehicular access onto the arterial highway. Points of access to the arterial street shall be spaced at a minimum of 660 feet. A planting strip having a minimum width of twenty feet shall be provided between the pavement of the arterial street and the pavement of the marginal street. The minimum width of the right of way shall be fifty feet.
(d) Alleys shall not be approved in residential subdivisions, except where justified by extreme conditions. Alleys may be required in commercial and industrial districts if other provisions cannot be made for adequate service access. The minimum widths for alleys shall be twenty-five feet for the right of way and twenty feet for the pavement width.