If the required improvement work is not completed satisfactorily before the final or parcel map is filed, the owner or owners of the subdivision shall, concurrently with the approval of such map, enter into an agreement with the City providing for completion of said improvements within a reasonable period of time, as determined by the City. Such agreement may provide for the improvements to be installed in units, for extensions of time under specified conditions, or for the termination of the agreement upon a reversion of the subdivision or a part thereof to acreage. Such agreement shall be secured by a good and sufficient bond payable to the City, approved by the City Council, or by the deposit of money or negotiable securities with the City, as provided in the Subdivision Map Act. (Ord. 89-2 § 2, 1989; Ord. 66 NS § 5, 1950; prior code § 20-25.)