N.Y. County Law § 280-S
Whenever the governing body shall determine it necessary to acquire additional lands or interests in lands or to acquire or to construct dunes, bluffs, bulkheads, dikes, groins, jetties, fills or other works including all necessary facilities and equipment appurtenant thereto; or whenever the governing body shall determine it necessary for the proper maintenance and service of such facilities to increase, improve or reconstruct the facilities thereof, including the acquisition of additional lands, or interests in land therefor, it may cause the same to be accomplished without further authorization, provided, however, that if it is proposed to finance any part of the cost thereof by the issuance and sale of capital notes or serial bonds, such improvement shall not be undertaken unless authorized by proceedings taken in the same manner as the proceedings taken for the original establishment of the district, except that the sole determination which the governing body shall make is whether such improvement is in the public interest, and if zones of assessment have been established, said governing body shall further determine the allocation of the cost thereof as between such zones.
N.Y. CountyLaw § 280-S