(a) Blocks. The following regulations shall govern the design and layout of blocks:
(l) The arrangement of blocks shall be such as to conform to the street planning criteria set forth above and shall be arranged to accommodate lots and building sites of the size and character required for the district as set forth in this chapter or in the Zoning Code and to provide for the required community facilities.
(2) Irregularly shaped blocks, those intended for cur-de-sacs or loop streets and those containing interior parks or playgrounds shall be approved by the Commission when properly designed and located and when the maintenance of interior public spaces is covered by agreements.
(3) No block shall be longer than 1,500 feet or less than 500 feet.
(4) Where blocks are over 900 feet in length, a crosswalk easement not less than ten feet in width at or near the halfway point may be required, if necessary, to provide proper access to schools, recreational areas, shopping centers and other facilities.