Sparkplug lighthouses are cast iron structures built at
offshore locations. The keeper's quarters is a round
building, usually three stories in height. The round lantern
room sits atop the keeper's quarters, and the whole
structure rests on a solid foundation, usually a concrete or
stone caisson. The Harbor of Refuge Light at Lewes,
Delaware, shown at right, is a typical example. Completed in
1926, it is also the last one ever built.
Because of their shape, these lighthouses have come to be
called "sparkplugs." Before the day of gasoline engines,
they were sometimes called "coffee pots." In many places
they were called "bug lights," because at a distance they
appeared short and broad, rather like a beetle on the
surface of the water.
Sparkplugs were prefabricated, brought to the site by
barge, and put in place by floating cranes. They were a
low-cost solution to the problem of providing offshore
lighthouses in the sounds and bays of the northeastern and
mid-Atlantic states, where all but three of the surviving
examples are located.
Harbor of Refuge Light, Lewes, Delaware, April 2008
Flickr Creative Commons photo by reivax
Surviving Sparkplug Towers
If sparkplug towers were deactivated, they became maintenance
problems and hazards to navigation. Before the recent interest in
lighthouse preservation took hold, the Coast Guard quickly demolished
deactivated sparkplugs. As a result, most of the surviving
examples are active lighthouses.
There are 33 surviving sparkplug lighthouses. Here they are, in
(approximate) order of completion:
(Bug Light), Massachusetts (1871), Plymouth Harbor
Channel Lower Range Front, Maryland (1873), Chesapeake
Beds, New Jersey (1880), New York Harbor
Flats, Massachusetts (1881), Fall River
Point Bar, Maryland (1882), Chesapeake Bay endangered
Island, Maryland (1882), Chesapeake Bay endangered
Harbor (Chatham Rocks), Connecticut (1882), Long Island
Shoal, Rhode Island (1883), Providence River
Reef (Kate's Light), New Jersey (1883), New York Harbor
(Kingsland Point), New York (1883), Hudson River
Reef, New York (1884), Fisher Island Sound
- Sakonnet, Rhode Island (1884), Rhode Island Sound
(Lewes) Breakwater, Delaware (1885), Delaware Bay
River (Bar Point Shoal), Michigan (1885), Lake Erie
Beach, Michigan (1885), Lake Huron
Breakwater, Connecticut (1886), Long Island Sound
Channel, Maine (1890), Lubec Channel
Rocks, Maine (1890), East Penobscot Bay
News Middle Ground, Virginia (1891), Hampton Roads
Point Ledge, Maine (1897), Portland Harbor
Shoal, New Jersey (1898), New York Harbor endangered
Beach, Rhode Island (1899), Narragansett Bay
Point, New York (1899), Long Island Sound
Island Shoal, Rhode Island (1901), Narragansett Bay
Bank (Staten Island Range Front), New York (1901), New York
Ledge, Connecticut (1902), Long Island Sound
Island, Maryland (1902), Chesapeake Bay
Ledge, Connecticut (1906), Long Island Sound
Harbor West Pierhead, Ohio (1911), Lake Erie
- Miah Maull Shoal, New Jersey (1913), Delaware Bay
Shoal, New Jersey (1914), Delaware Bay
Shoal, Virginia (1914), Chesapeake Bay
of Refuge Breakwater, Delaware (1926), Delaware Bay
Duxbury Pier (Bug) Light, Plymouth, Massachusetts, August 2009
Flickr Creative Commons photo by David Sugden
Of the 33 lighthouses, all but the first few have very similar, three-story
designs. The oldest sparkplug, Plymouth Harbor's "bug light", has only
two stories in the keeper's quarters. The Craighill Channel range light
has a unique, single-story design. The Great Beds, Jeffrey's Hook, and
Borden Flats lighthouses have relatively slender towers which must have
provided cramped quarters for the keepers. Over the years the towers gradually
became wider to allow for more generous crew space.
Tarrytown Light, Tarrytown, New York, September 2009
Flickr Creative Commons photo by Dan Dvorscak
Hooper Island Light, Hoopersville, Maryland, September 2006
Flickr Creative Commons photo by Craig Bruce
Here is a list of sparkplug lighthouses that
have been lost:
Rock, Rhode Island (1882), Rhode Island Sound, destroyed by
the great hurricane of 1938
Island, Massachusetts (1890), Boston Harbor, demolished by the
Coast Guard in 1982
Ledge, Maine (1890), Frenchman's Bay, destroyed by a
storm in the late 1930s
Orchard Shoal, New York (1893), New York Harbor, destroyed by Hurricane Sandy in 2012
Lake, New York (1894), Hudson River, demolished in 1923
after its foundation failed
- Sperry (New Haven Outer
Breakwall), Connecticut (1900), Long Island Sound, demolished
by the Coast Guard in 1933
Bank, Texas (1906), Gulf of Mexico, demolished
by the Coast Guard in
of Cross Ledge, New Jersey (1910), Delaware Bay, demolished
in 1954 after being heavily damaged by collision with a ship
Saving the Sparkplugs
Sharps Island Light, Tilghman Island, Maryland, July 2004
Flickr Creative Commons photo by Craig Bruce
Preservation of sparkplug lighthouses is not an easy
business. The iron towers rust and deteriorate quickly if
they are not painted regularly. The towers are exposed to
damage from waves, winter ice, and collision with ships. It
was ice that pushed the Sharps Island Light over at a
15° angle in the winter of 1976-77 (see photo at left).
A winter storm toppled the former Crabtree
Ledge Light in Maine. Rust and decay caught up with the
Light in Boston Harbor, demolished in 1982.
Some of the sparkplugs are close to shore, but most are
several miles out in the water, too far for convenient
access. The Coast Guard has acted to place many of them under the National Historic Lighthouse
Preservation Act process, with mixed results. Because it would be difficult to provide public access, preservation groups have been reluctant to accept ownership of these lighthouses, so many of them are being auctioned off to private owners. Several of these owners have invested heavily in restoring their lighthouses, but others seem overwhelmed by the task and have made little progress.
Despite these difficulties, there have been a number of successful
efforts to preserve sparkplug lighthouses.
- In Plymouth, Massachusetts, Project
Bug Light led restoration projects for the Duxbury Light in
the mid-80s and again in the mid-90s.
- In Lubec, Maine, public pressure convinced the Coast Guard to
restore the Lubec Channel Light in 1993-94 instead of demolishing
- At Sakonnet, Rhode Island, the Friends of Sakonnet Point
Lighthouse restored the abandoned sparkplug light and reactivated
it in 1997. A complete restoration of the lighthouse was nearing completion in 2012.
- In 1999, the Portland
Harbor Museum took control of the Spring Point Ledge Light,
which is linked to shore by a breakwater, and opened it for guided
- In Michigan, the Harbor Beach Lighthouse and Breakwall
Preservation Society is working to preserve Lake Huron's only
- In Delaware, the Delaware
River and Bay Lighthouse Foundation has taken ownership of the
Harbor of Refuge Light and is working to restore the building.
Since 2003 the lighthouse has been open for public tours. In 2004
DRBLHF expanded its preservation efforts to include the nearby
Delaware Breakwater Light, and that light opened to the public
for the first time in the summer of 2005.
- In Rhode Island, the Friends
of Plum Beach Lighthouse carried out in 2003 the difficult
task of restoring and reactivating a sparkplug tower inactive for
nearly 60 years.
- The city of Warwick, Rhode Island, received the title to
Conimicut Light in September 2004 and is moving ahead with plans
- The Noble Maritime Collection, Staten Island, has taken ownership of Robbins Reef (Kate's) Light and is working to restore it.
- Westchester County and the Village of Sleepy Hollow are working to restore the Tarrytown Lighthouse.
This makes 11 out of 33 sparkplugs under some sort of community-based preservation
or preservation effort. Most of the remaining sparkplugs have been sold into private ownership. In a few cases this has worked well: private owners have restored the Borden Flats and Newport News Middle Ground lighthouses, for example. But in many cases the work has been too great for private owners.
As of September 2018 three sparkplugs were on the Lighthouse Digest Doomsday
List: Bloody Point Bar, Romer Shoal, and Sharps Island.
Return to the Lighthouse Directory
Posted January 16, 2002. Checked and revised September 19, 2018.
Site copyright 2018 Russ Rowlett and the University of North Carolina
at Chapel Hill.