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Deer Island Lighthouse

Fl WR 5s🇺🇸Northern Massachusetts, USOperational

This iron lighthouse, constructed in 1890, stands 10 meters tall with its focal height at 16 meters. The structure features a square design and originally housed a three-story dwelling with a veranda and boat davits. Its water supply came from a cistern within the base, and a spiral staircase provided access from the cellar to the top floor. Initially displaying a fixed white light, it was later updated to a flashing red light every thirty seconds before adopting its current alternating red and white flashes. In 1982, the original light was replaced by a white fiberglass tower, although this change prompted complaints about visibility.

Why it matters: The lighthouse marks the end of a reef extending south from Deer Island into Boston Harbor.

Background
Deer Island Light is a lighthouse in Boston Harbor, Boston, Massachusetts. The actual light is 53 feet (16 m) above Mean High Water. Its alternating white and red light is visible for 9 nautical miles (17 km; 10 mi). The light is at the end of a reef that extends about 1,500 feet (460 m) south from Deer Island. The location first had a stone beacon 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 100 feet (30 m)
Characteristic Signature
Fl WR 5s
Flash Type
Flashing
Light Color
WR
Flash Count
1 flash
Interval
5s
Focal Height
16m
Year Built
1890
Admiralty No.
J0324
USCG No.
1-10795
ARLHS No.
USA-1096
Wikidata
Q5250767
OpenStreetMap
View on OSM →
Tower Height
10m
Tower Shape
square
Material
iron
City
Northern Massachusetts
Country
🇺🇸US
Latitude
42.3398°
Longitude
-70.9545°
Flag
Type
Name
Dist.
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How do mariners identify Deer Island Lighthouse at night?+
Deer Island displays the characteristic Fl WR 5s — 1 wr flash every 5 seconds. Each lighthouse has a unique flash pattern published in the List of Lights, allowing mariners to positively identify it and distinguish it from other navigation aids in the area. The wr color may indicate a specific sector or warning zone.
Which ports and harbors does Deer Island Lighthouse guide vessels into?+
Deer Island Lighthouse assists vessels approaching 5 nearby ports. The closest is WINTHROP at 1.9 NM to the NNW. Other ports served include SOUTH BOSTON (3.3 NM W), Boston (4.4 NM WNW), Dorchester (4.8 NM WSW), Everett (5 NM WNW). Mariners should consult the relevant chart for full approach and pilotage information.
Is Deer Island Lighthouse still active and maintained?+
Yes, Deer Island Lighthouse is currently operational. It is actively maintained and continues to emit its characteristic light signal for marine navigation. Most modern lighthouses are automated and monitored remotely by the national maritime authority.
How can I track vessels near Deer Island Lighthouse?+
You can track vessels near Deer Island Lighthouse in real time using MarineRadar. The platform shows live AIS positions of ships in the area, including vessel name, type, flag, speed, and course. Use the "Track Vessels Nearby" button on this page to open the live map centered on this lighthouse.