Gravelly Shoal Light

Infobox_Lighthouse
name = Gravelly Shoal Light


caption = Undated USCG photo
location = Saginaw Bay, Michigan
coordinates = coord|44|1|6|N|83|32|14|W
yearbuilt = 1939
yearlit = 1939
automated =
yeardeactivated =
foundation = 50-foot diameter concrete pier [ [http://www.detnews.com/apps/pbcs.dll/article?AID=/20080520/SPECIAL01/80519001 Detroit News, Interactive map on Michigan lighthouses.] ]
construction = Steel-sided tower
shape = Art Deco
marking = white, gray scaffold atop
height = Tower - convert|65|ft|m
elevation = Focal plane - convert|75|ft|m
lens =
currentlens = 375 mm lens [ [http://www.unc.edu/~rowlett/lighthouse/miel.htm Lighthouse Digest, Gravelly Shoal Light, University of North Carolina.] ]
intensity = 15,000 candlepower [ [http://www.terrypepper.com/lights/huron/gravelly-shoal/gravelly-shoal.htm Terry Pepper, Seeing the Light, Gravelly Shoal Light.] ]
range = convert|11|mi|km
characteristic = red flash every 6 seconds
fogsignal = Every 30 seconds, operates year round. [ [http://www.unc.edu/~rowlett/lighthouse/miel.htm Lighthouse Digest, Gravelly Shoal Light, University of North Carolina.] ]
Radio beacon signal transmitted at 296 kilocycles, and emitted a group of 0.5 -second dashes for 15.5 seconds, followed by 14.5 seconds of silence. [ [http://www.terrypepper.com/lights/huron/gravelly-shoal/gravelly-shoal.htm Terry Pepper, Seeing the Light, Gravelly Shoal Light.] ]
admiralty =
NGA =
ARLHS = USA-340
USCG = 7-10540

Gravelly Shoals Light is an automated lighthouse that is an active aid to navigation on the shallow shoals extending southeast from Point Lookout on the western side of Saginaw Bay. The light is situated about 2.7 miles offshore and was built to help guide boats through the deeper water between the southeast end of Gravelly Shoals and Charity Island. Architecturally this is considered to be Art Deco style. [ [http://www.lighthousedepot.com/DATABASE/uniquelighthouse.cfm?value=525 Lighthouse Depot, Gravelly Shoal light.] ]

The light tower was built in 1939 and replaced an earlier gas-lit buoy. It also displaced the Charity Island Light, which was constructed in 1857, and operated until 1930.

This light is designed as an autonomous automated electrified station. It is under the control and maintenance of Coast Guard Station in Tawas City, Michigan. Ordinarily it displays a 15,000 candlepower 375 mm light powered by a 120 volt electric lamp. Power is supplied through a submarine cable, which crosses the shoal from Point Lookout. The 75-foot focal plane makes its flash (1-second every 5 seconds) visible for 16 miles. It is supplemented by a standby 110 candlepower acetylene light with a half second flash every three seconds -- which activates automatically if there is a power failure. In foggy weather, mariners are warned by twin compressed-air two-tone #3 diaphones, which operate on a 30-second cycle (3-second blast followed by 27 seconds of silence). [ [http://www.terrypepper.com/lights/huron/gravelly-shoal/gravelly-shoal.htm Terry Pepper, Seeing the Light, Gravelly Shoal Light.] ]

The National Data Buoy Center lists the Site Elevation as 179.2 meters above sea level.

The National Weather Service operates an automated weather observing station at the lighthouse.

An added large steel tower atop the light is a radio beacon. The 1953 Coast Guard Light List indicates that the signal transmitted at 296 kilocycles, send forth a group of 1/2-second dashes for 15.5 seconds, followed by 14 1/2 seconds of silence. As of 2001, both the light and radio beacon served as active navigational aids. [ [http://www.terrypepper.com/lights/huron/gravelly-shoal/gravelly-shoal.htm Terry Pepper, Seeing the Light, Gravelly Shoal Light.] ]

A good passing view of the light can be had while riding the ferry from Au Gres to Charity Island, which is ten miles to the east in the middle of Saginaw Bay. [ [http://www.lighthousedepot.com/DATABASE/uniquelighthouse.cfm?value=525 Lighthouse Depot, Gravelly Shoal Light/Charity Island.] ] Tours of the Charity Island (and even dinner cruises) are available, which can include the privately-owned, rebuilt Charity Island Lightlightkeeper's house. They are available from Charity Island Transport, Inc. in Au Gres, Michigan on the mainland, south of Tawas. [ [http://www.charityisland.net/ferry.html Charity Island ferry service.] ]

ee also

*Lighthouses in the United States

Notes

Bibliography and further reading

* [http://www.michiganlighthouse.org/bibliography.html Bibliography on Michigan lighthouses.]
* Hyde, Charles K., and Ann and John Mahan. "The Northern Lights: Lighthouses of the Upper Great Lakes." Detroit: Wayne State University Press, 1995. ISBN 0814325548 ISBN 9780814325544.
* Jones, Ray & Bruce Roberts, "American Lighthouses" (Globe Pequot, September 1, 1998, 1st Ed.) ISBN 0762703245; ISBN 978-0762703241.
* Jones, Ray,"The Lighthouse Encyclopedia, The Definitive Reference" (Globe Pequot, January 1, 2004, 1st ed.) ISBN 0762727357; ISBN 978-0762727353.
* Noble, Dennis, "Lighthouses & Keepers: U. S. Lighthouse Service and Its Legacy" (Annapolis: U. S. Naval Institute Press, 1997). ISBN 1557506388; ISBN 9781557506382.
* Oleszewski, Wes, "Great Lakes Lighthouses, American and Canadian: A Comprehensive Directory/Guide to Great Lakes Lighthouses", (Gwinn, Michigan: Avery Color Studios, Inc., 1998) ISBN 0-932212-98-0.
* Penrod, John, "Lighthouses of Michigan", (Berrien Center, Michigan: Penrod/Hiawatha, 1998) ISBN 9780942618785 ISBN 9781893624238.
*
* Putnam, George R., "Lighthouses and Lightships of the United States", (Boston: Houghton Mifflin Co., 1933).
* United States Coast Guard, "Aids to Navigation", (Washington, DC: U. S. Government Printing Office, 1945).
* [http://www.uscg.mil/History/weblighthouses/h_lhbib.asp United States Coast Guard, "Aids to Navigation Historical Bibliography".]
*
* Wagner, John L., "Michigan Lighthouses: An Aerial Photographic Perspective", (East Lansing, Michigan: John L. Wagner, 1998) ISBN 1880311011 ISBN 9781880311011.
* Wargin, Ed, "Legends of Light: A Michigan Lighthouse Portfolio" (Ann Arbor Media Group, 2006). ISBN 9781587262517.
* Wright, Larry and Wright, Patricia, "Great Lakes Lighthouses Encyclopedia" Hardback (Erin: Boston Mills Press, 2006) ISBN 1550463993

External links

* [http://www.detnews.com/apps/pbcs.dll/article?AID=/20080520/SPECIAL01/80519001 Detroit News, Interactive map on Michigan lighthouses.]
* [http://www.lighthousecentral.com/lighthouse_gallery.php4?lighthouse=Gravelly%20Shoal%20Light Lighthouse Central, Gravelly Shoal Light Photographs, History and Directions, "The Ultimate Guide to East Michigan Lighthouses" by Jerry Roach] (Publisher: Bugs Publishing LLC - July 2006).] ISBN 0974797715; ISBN 9780974797717.
* [http://www.unc.edu/~rowlett/lighthouse/miel.htm Lighthouse Digest, Gravelly Shoal Light, University of North Carolina.]
* [http://www.lighthousesrus.org/Maps/GL/HuronW.htm Interactive map of lighthouses in area] by LighthousesRus.
* [http://www.michigan.gov/documents/hal_mhc_shpo_lightmap_50933_7.pdf Map of Michigan Lighthouses] from Michigan.gov.
* [http://www.michiganlights.com/gravelyshoallh.htm Michigan lighthouse conservancy, Gravelly Shoal Light.]
* [http://ndbc.noaa.gov/station_page.php?station=gslm4 National Buoy Data Center with automatic readout of wind, waves and weather.]
* [http://haldigitalcollections.cdmhost.com/cdm4/item_viewer.php?CISOROOT=/p4006coll7&CISOPTR=165&CISOBOX=1&REC=3 Photograph of Coast Guard boat at Gravelly Shoal, circa 1942, Archives of Michigan.]
* [http://www.charityisland.net/gallery.html Photos of Gravelly Shoal Light (current) from ferry.]
* [http://www.terrypepper.com/lights/huron/gravelly-shoal/gravelly-shoal.htm Terry Pepper, Seeing the Light, Gravelly Shoal Light.]
* [http://www.us-lighthouses.com/displaypage.php?LightID=217 us-lighthouses.com on Gravelly Shoal Light.]
* [http://www.cr.nps.gov/Maritime/minoraid.htm Significant Unmanned Aids] from the National Park Service Inventory of Historic Light Stations
* United States Coast Guard's [http://www.uscg.mil/history/weblighthouses/LHMI.asp complete list of Michigan lights but not including Gravelly Shoal Light.]
* [http://www.navcen.uscg.gov/pubs/LightLists/V7COMPLETE.PDF Volume 7, US Coast Guard Lightlist (PDF).]