N.Y. SCC Law § 92

§ 92. Repair of sidewalks; removal of snow and ice. The commissioner\nof public works shall have full power and authority to require the owner\nof property abutting upon a street to repair any sidewalk in front\nthereof or bring the same to true grade, and to remove the snow and ice\ntherefrom. Where the owner of such property shall fail or neglect to\nrepair any sidewalk or bring the same to true grade for five days after\nwritten notice so to do has been served on him, either personally or by\ndelivering the same at his residence, or if he be a non-resident by\nmailing the same to him at his last known place of residence, or if the\nname of the owner or his place of residence can not be ascertained after\ndue diligence, by posting the same in a conspicuous place upon the\npremises; or where the owner of any such premises shall fail or neglect\nto remove snow and ice from any such sidewalk after the same has\nremained thereon for more than twelve hours, and the commissioner shall\nhave repaired such sidewalk or brought the same to grade or removed the\nice or snow therefrom, a bill for the expenses incurred thereby shall be\npresented to the owner personally or by leaving the same at his\nresidence or, if he be a non-resident, by mailing the same to him at his\nlast known place of residence, or, if the name of such owner or his\nplace of residence can not be ascertained after due diligence, by\nposting the same in a conspicuous place on the premises; and, if he\nshall fail to pay the same within ten days thereafter, the commissioner\nshall file each year immediately preceding the time for making the\nannual assessment-roll his certificate of the actual cost of the work,\ntogether with a statement as to the property in front of which the\nrepairing or grading or cleaning was done, with the assessors of the\ncity, who shall, in the preparation of the next assessment-roll of\ngeneral city taxes, assess such amount upon such property, and the same\nshall be levied, corrected, enforced and collected in the same manner,\nby the same proceedings, at the same time, under the same penalties and\nhaving the same lien upon the property assessed as the general city tax\nand as a part thereof.\n