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Maritime Heritage: Field Research
Montebello

Montebello Launch
Oil Tanker Montebello being launched on 24 January 1921 at Southwestern Shipbuilding Company in East San Pedro, CA. (Credit: Unocal)

Just south of the Monterey Bay National Marine Sanctuary boundary are the remains of the oil tanker Montebello. Built in 1921 at the Southwestern Shipbuilding Company in San Pedro California, the shelter deck tanker had an overall length of 457 feet (139 meters). The tanker, carrying over 3 million gallons of Santa Maria crude oil, was sunk by a single torpedo fired by a Japanese submarine during World War II on December 23, 1941; just two weeks after the attack on Pearl Harbor. It is believed the 18 cargo tanks containing the crude oil were not damaged during the attack.

The Montebello sits 900 feet below the surface of the Pacific Ocean, approximately seven miles off the coast of California near the town of Cambria, in San Luis Obispo County. The shipwreck Montebello has been visited several times by archaeologists, historians, and biologists to inspect the vessel and surrounding area for oil and wildlife.

In September of 2003, staff members from the Monterey Bay and Channel Islands National Marine Sanctuaries, and local agencies visited the oil tanker Montebello to conduct reconnaissance dives to monitor and characterize the condition of the vessel, and characterize the fish and invertebrate assemblages. No evidence of oil was found.

In early 2009, California Assemblyman Sam Blakeslee initiated a partnership with the Department of Fish and Game's Office of Spill Prevention and Response (OSPR). Blakeslee requested OSPR to coordinate a risk assessment to determine the likelihood of an oil release and the potential adverse effects this would cause on the Central Coast. Soon after, a multi-agency workgroup, the Montebello Assessment Task Force was formed to assess potential impacts to the marine environment and the California coast from the sunken oil tanker Montebello.

In September 2011, the U.S. Coast Guard awarded a contract to Global Diving and Salvage, Inc. to determine if oil was present aboard the sunken ship S.S. Montebello. The survey was conducted in October 2011, at which time a Unified Command led by the U.S. Coast Guard and California Department of Fish and Game's Office of Spill Prevention and Response assessed cargo and fuel tanks of the sunken ship S.S. Montebello. The Unifed Command determined that there is no substantial oil threat from the Montebello to California waters and shorelines. To view the Final Press Release of the 2011 Montebello Assessment, click here. A final report is expected in spring 2012.

 

S.S. Montebello Videos

picture of SS Monteb
Chapter One: Construction History
(51.4MB MOV)
 
picture of SS Monteb
Chapter Two:
War

58.3MB MOV
 
picture of SS Monteb
Chapter Three: Rediscovery
(70.3MB MOV)

 

S.S. Montebello Images

Montebello torpedo impact zone   Drawing of the S.S. Montebello pre-loss, illustrating the oil tank locations and torpedo impact zone.
Credit: Robert Schwemmer/NOAA National Marine Sanctuaries.
(Image 536KB)
Montebello site drawing   Drawing of the S.S. Montebello wreck site from the Monterey Bay National Marine Sanctuary 2003 survey.
Credit: Robert Schwemmer/NOAA National Marine Sanctuaries.
(Image 292KB)
Montebello cowl ventilator   2003 Montebello Visual Survey. Cowl ventilator collapsed on the shelter deck of the S.S. Montebello.
Credit: Robert Schwemmer/NOAA National Marine Sanctuaries.
(Image 516KB)
Nanuq   2011 Montebello Assessment. M/V Nanuq served as the support vessel to conduct the remotely operated vehicle (ROV) 24 hour-a-day operation. The ship is equipped with dynamic positioning (DP), a computer controlled system to automatically maintain the vessel's position and heading by using its own propellers and thrusters.
Credit: Robert Schwemmer/NOAA National Marine Sanctuaries.
(Image 220KB)
ROV Launch   2011 Montebello Assessment. Saab Seaeye Cougar XT ROV housed inside the tethered management system (TMS) being deployed off the M/V Nanuq from the boom of the launch and recovery system (LARS).
Credit: Robert Schwemmer/NOAA National Marine Sanctuaries.
(Image 188KB)
Montebello propeller blades   2003 Montebello Visual Survey. S.S. Montebello's 18 foot bronze propeller nearly 900 feet below the surface.
Credit: Robert Schwemmer/NOAA National Marine Sanctuaries.
(Image 292KB)
ROV Cougar   2011 Montebello Assessment. Global Diving & Salvage's Saab Seaeye Cougar XT ROV equipped with a barnacle buster tool used to clean the hull of the Montebello prior to conducting ultrasonic thickness gauging of the steel hull.
Credit: Robert Schwemmer/NOAA National Marine Sanctuaries.
(Image 328KB)
ROV Control Room   2011 Montebello Assessment. ROV control room on board the M/V Nanuq from which the ROV pilots, navigation technician and naval architect conducted operations.
Credit: Robert Schwemmer/NOAA National Marine Sanctuaries.
(Image 240KB)
Coupon Recovery   2011 Montebello Assessment. Robert Schwemmer, West Coast Regional Maritime Heritage Coordinator ONMS, holding a coupon of the steel hull inside a hole-saw that was recovered utilizing the ROV. The coupon will be used to determine the corrosion rate of a 90 year old vessel submerged in 900 feet of water for 70 years.
Credit: Eric Crampton/Global Diving & Salvage.
(Image 304KB)

 

Related Links
Visit the following web sites for more information on the Montebello:

West Coast Shipwreck Database:
http://channelislands.noaa.gov/shipwreck/dbase/montebello.html

Brief history and pictorial of the vessel:
http://channelislands.noaa.gov/shipwreck/dbase/montebello_2.html

Expeditions to the Shipwreck Montebello (Ecosystem Observations 2005, p.25):
http://montereybay.noaa.gov/reports/ecoobs.html#2005

Summary of the 2010 seafloor mapping survey:
http://www.mbari.org/news/news_releases/2010/auv-montebello/auv-montebello-release.html

California's Office of Spill Prevention and Response (OSPR) website on Montebello and Assessment Task Force:
http://www.dfg.ca.gov/ospr/NewsPubs/Montebello/index.aspx

NPR: All Things Considered
Six Miles Off Shore: The Wreck of the Montebello (10/18/11)
http://www.npr.org/2011/10/18/141453907/oiafter-the-wreck-of-montebello

Final Press Release of the 2011 Montebello Assessment, concluding "No visual evidence of oil found onboard S.S. Montebello" (10/20/11):
http://montereybay.noaa.gov/new/archive2011.html

NOAA Researchers Investigate Shipwrecks and 'Mystery Oil Spills'
Part 1: A new field of study and the 'Montebello Mystery' (12/8/11)
http://oceanservice.noaa.gov/news/features/dec11/mysteryoil_pt1.html

NOAA Researchers Investigate Shipwrecks and 'Mystery Oil Spills'
Part 2: Long-sunk secrets rise slowly to the surface (12/12/11)
http://oceanservice.noaa.gov/news/features/dec11/mysteryoil_pt2.html

URL: http://montereybay.noaa.gov/maritime/frmontebello.html    Reviewed: March 04, 2014
Web Site Owner: National Ocean Service

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