N.Y. County Law § 280
Whereas beach erosion along the shoreline of this state and especially along the shoreline in the county of Suffolk causes loss of life and damage to property and constitutes a menace to the health, safety and welfare of the people of this state in general and the residents of Suffolk in particular, it is the sense of the legislature that in order to arrest erosion and alleviate or prevent damage resulting therefrom and as protection from storms, the governing body of the county of Suffolk is hereby authorized to establish or extend county hurricane protection, flood and shoreline erosion control districts in the manner hereinafter provided for the purpose of constructing and reconstructing dunes, bluffs, bulkheads, dikes, groins, jetties, fills and other works and improvements upon lands and lands under water owned by such county, or any town, village, park, or existing hurricane protection, flood and shoreline erosion control district or private lands upon which the county has obtained easements or a fee title. No county district shall be established hereunder which shall consist wholly of territory within one town or village.
N.Y. CountyLaw § 280