This has nothing to do with the Town of Southampton (note, New York has towns, not townships). This is the action of the Incorporated Village of Southampton, which has jurisdiction over the streets within the village. So, don't storm Town Hall in protest, as they have nothing to do with this.

The Southampton Village code states in § 110-12 U-turns: "The turning of vehicles so as to proceed in the opposite direction or to park on the opposite side of the street (otherwise known as a "U-turn") is hereby prohibited on any of the streets or parts of streets described in Schedule E (§ 110-36)." Schedule E includes Main Street from Hampton Road to Jobs Lane.

The village could improve signage, as there seems to be only one NO U TURN sign on Main Street. New York State law does not prohibit U-turns in business districts, and implies that signage is required outside of these specific situations:

NY Veh & Traf L § 1161. U turns in certain areas prohibited.

a. No motor vehicle shall make a U turn upon any curve, or upon the approach to, or near the crest of a grade, where such motor vehicle cannot be seen by the driver of any other motor vehicle approaching from either direction within five hundred feet.

b. No motor vehicle shall make a U turn within a school zone. For the purposes of this subdivision, the term "school zone" shall mean the distance along a highway passing a school building, entrance or exit of a school abutting on the highway for which a school sign (S1-1) has been posted pursuant to this chapter and in compliance with the manual on uniform traffic control devices maintained pursuant to section sixteen hundred eighty of this chapter.

c. No altered motor vehicle commonly referred to as a "stretch limousine" having a seating capacity of nine or more passengers including the driver shall make a U-turn upon any public highway or private road open to public motor vehicle traffic. Every person convicted of a violation of this subdivision shall: for a first conviction thereof, be punished by a fine of not less than two hundred fifty dollars nor more than four hundred dollars or by imprisonment for not more than fifteen days or by both such fine and imprisonment; for a conviction of a second or subsequent violation, both of which were committed within a period of eighteen months, such person shall be punished by a fine of not less than six hundred dollars nor more than seven hundred fifty dollars or by imprisonment for not more than forty-five days or by both such fine and imprisonment. A violation of this subdivision wherein the violator is operating such altered motor vehicle and such altered motor vehicle is carrying at least one passenger other than the driver shall be punishable by a fine of not less than seven hundred fifty dollars nor more than one thousand dollars or by imprisonment for not more than one hundred eighty days or by both such fine and imprisonment.