Port Ewen is a hamlet (and census-designated place) in Ulster County, New York, United States.

Port Ewen was served by the West Shore Railroad, which shipped, among other freight, high explosives produced by the Nitro Powder Company in Kingston.

[2] Before the opening of the Kingston–Port Ewen Suspension Bridge in 1921, those wishing to cross the Rondout Creek would have to take the Skillypot, a chain ferry that ran to Sleightsburgh, noted for its sporadic service.

[4] The Port Ewen plant produced a range of special detonators designed for military use, as well as construction jobs that required blasts of dynamite.

The Church of the Presentation of the Blessed Virgin Mary was dedicated by Archbishop John McCloskey on June 14, 1874.

A Class 2 site represents a significant threat to public health or the environment and action is required.

"[10] The downstream spread of contaminants has impacted Port Ewen from the original site in Ulster Park.

Volatile organic compounds (e.g., chlorinated solvents such as trichloroethene or TCE) are also present in the groundwater near the former shell plant.

[11][12] According to the NY DEC, "Former manufacturing operations for primers and igniters for explosives took place in the developed portion of the site, which occupies approximately 100 acres.

"[13] A New York State Department of Environmental Conservation Superfund Community Report for June 2024 indicated that "On May 21, 2024, DEC issued a Notice of Violation (NOV) to the town of Esopus for the unpermitted work.

The town immediately worked closely with DEC to implement corrective measures, including covering areas of soil disturbance and installing temporary fencing near the elementary school to reduce the risk of public exposure."

[13] Levels of lead exceeding 15 ppb have been found in some water supplies of Robert R. Graves Elementary, Port Ewen's public elementary school, according to an August 2021 analysis completed by EnviroTest Laboratories, LLC, with the highest recorded level of 90 ppb.

Sojourner Truth, American abolitionist and activist, was enslaved in West Park, a few miles south of Port Ewen, also within the Town of Esopus.

Luann de Lesseps, former countess and current star of Real Housewives of New York City, purchased a home along the Hudson River in 2018.