Deer Island Light is a lighthouse in

Boston Harbor Boston Harbor is a natural harbor and estuary of Massachusetts Bay, and is located adjacent to the city of Boston, Massachusetts. It is home to the Port of Boston, a major shipping facility in the northeastern United States. History ...

, Boston, Massachusetts. The actual light is above

Mean High Water A chart datum is the water level surface serving as origin of depths displayed on a nautical chart. A chart datum is generally derived from some tidal phase, in which case it is also known as a tidal datum. Common chart datums are ''lowest ast ...

. Its alternating white and red light is visible for . The light is at the end of a reef that extends about south from Deer Island. The location first had a stone

beacon A beacon is an intentionally conspicuous device designed to attract attention to a specific location. A common example is the lighthouse, which draws attention to a fixed point that can be used to navigate around obstacles or into port. More mode ...

in 1832. The first light, a sparkplug type light, was lit in 1890. It cost about $50,000. It included a three-story dwelling, a veranda with boat davits, and a circular parapet. The water supply was a cistern in the base of the structure. A spiral staircase ran from the cellar to the top floor. It had a fixed white light, which was changed to flashing red every thirty seconds and then to the present alternating red and white flashes. The old light gradually deteriorated and was replaced in 1982 by a white fiberglass tower. The white tower raised complaints because it blended in with the background and was hard to see, so the Coast Guard moved it to Great Point Light, Nantucket, as a temporary replacement when that tower was destroyed by a storm in March 1984. A brown fiberglass tower was installed immediately thereafter. While the Spark plug light was interesting, it was much more expensive to maintain than the fiberglass structure. Imported from England, the pole light was the first of its kind in the United States. Between October 2015 and May 2016, the brown tower was dismantled and the light was moved about south of its previous foundation structure.U.S. Coast Guard

Local Notice to Mariners A Local Notice to Mariners is an authoritative instruction issued by a designated official, typically the harbormaster. United States In the United States, notices are issued by each U.S. Coast Guard District to disseminate important information ...

, District 1, Week 49/2015, p.12U.S. Coast Guard

District 1, Week 20/2016
p.12 The new light uses LED technology and sits on a steel skeletal tower, atop four piles. Like other lights in Boston Harbor, the automatic fog signal has been replaced by a Mariner Radio Activated Sound Signal (MRASS) which can be activated by nearby mariners by tuning their

marine VHF radio Marine VHF radio is a worldwide system of two way radio transceivers on ships and watercraft used for bidirectional voice communication from ship-to-ship, ship-to-shore (for example with harbormasters), and in certain circumstances ship-to-a ...

to channel 83A (157.17 5Mhz) and keying the transmitter five times consecutively.

Gallery

File:Deer Island Light Boston MA 2009.jpg, Deer Island Light in 2009, with

Deer Island Waste Water Treatment Plant The Deer Island Waste Water Treatment Plant (also known as Deer Island Sewage Treatment Plant) is located on Deer Island, one of the Boston Harbor Islands in Boston Harbor. The plant is operated by the Massachusetts Water Resources Authority ( ...

digesters in the background. File:Deer Island Light, June 19 2016.jpg, Deer Island Light in 2016, next to the old concrete foundation.

References

{{authority control Lighthouses completed in 1890 Lighthouses completed in 1984 Boston Harbor Lighthouses in Boston 1890 establishments in Massachusetts