The Search

Previous search efforts conducted between 1993 and 2018. MacKay survey not shown. (Image: Rockfish, Inc.)

Past Searches

Don MacKay 1985-1988 The first known search attempts were undertaken by Don Mackay, a real-estate developer in Los Angeles. The project was managed by Paul Tidwell and organized by Jay Fiondella, a restauranteur from Los Angeles. The survey focused on the presumption that the ship’s bearings reported in the newspaper accounts were based on true north. Navigation was done with Loran-C and mini-ranger positioning equipment. A number of targets were located and surveyed with ROVs. The wreck was not located because the search area did not include the actual location of the wreck.

Pacific Sea Resources 1993 The next known survey was undertaken by Bill Mathers, of Pacific Sea Resources, in September of 1993. The survey was managed by David Mearns and the work done by Oceaneering.

The survey resulted in the discovery of many targets but not the vessel. The survey covered more than 400 square miles and covered the location of the wreck. The vessel was probably not located because of the diminished stature of the wreck. The search was conducted using a 60Khz sonar with 800- and 1000-meter line spacing. The survey was conducted at a resolution of 1 meter per pixel.

Odyssey 1999, 2000, 2003 The 1999 survey used a depth sounder on a commercial vessel to analyze various targets either from the Oceaneering survey and data from commercial fishermen. This search resulted in deploying an ROV on a number of targets. The 2000 survey was managed by John Astley (UK) and the 2003 survey was managed by Ernie Tapenas. The resolution of the Tapenas survey was 0.5 meters per pixel. The resolution of the Astley survey is unknown. The Astley survey covered the location of the wreck. It is not know why the wreck was not discovered during this effort.

NOAA 2008-2010 NOAA conducted several surveys under the guise that they were general purpose surveys of the marine sanctuary. Even to the uninitiated, it is fairly obvious that they were also searching for the wreck. NOAA also conducted a swath bathymetry survey that entirely encompasses the high-probability area. It provides a high resolution look at the area.

Stabbert Marine – Mathers: Stabbert Marine teamed up with Bill Mathers to complete an AUV survey in the winter of 2018. The imagery was very high resolution and the areas they searched were completely eliminated from further consideration. The location covered by the survey did not include the location of the wreck.

Several other groups are known to have looked for the wreck or are continuing to look for it. An important fact is that the wreck is not outstanding but instead obscure; if it were easy to identify then it would have already been located. The biggest challenge with all previous attempts was the large size search area and the small size of the target. In order to find the vessel a more refined area had to be established and searched with better equipment and techniques.

Key Facts and Assumptions

In order to calculate the approximate location of the SS Pacific, certain information was compiled, including the intended course, departure time, speed, headings, knowledge of tidal and storm driven currents, wind speed, and direction. There was no way to know the exact values of any of these items; however, a probable range of values was determined, with an additional margin of error to accommodate the unusual circumstances of the sinking. Once this was accomplished, a probability analysis was completed, which showed high and low probability areas for locating the wreck. Fortunately, there were three different scenarios to consider: the route of the Pacific, the route of the S/V Orpheus, and the drifting survivors. 

Heading true or magnetic?
This was essential in determining the location, because the variation was 21.85 degrees to the east in November of 1875. Getting this wrong would mean that a search would not be conducted in the right area.

The Pacific‘s speed.
Dividing the distance traveled by the amount of time leads to a speed much faster than the actual speed through the water due to tidal currents. What is the range of possible speeds?

Course and time of turn at Cape Flattery
Did they make one turn or two? How does this affect the passage? Where was the turn made? There are witness statements before and after the turn, but when was the turn actually made?

Time of turn and course steered southward to San Francisco
We have a witness statement, but nothing definitive, on when they made the course change to San Francisco. Why were they so far from shore? The captain stated that they were 15-20 miles from shore. Why didn’t he know exactly how far from shore the vessel was traveling?

Weather and current effect on vessel’s offshore journey
The vessel sank in the first few hours of a very substantial storm. How did the currents affect the course of the vessel?

Time of sinking
There is a substantial difference in the recorded time of the sinking between the accounts of the two vessels. How can this be resolved?

The Orpheus
The Pacific collided with another vessel. What can be learned from the account of this other vessel? Where was it located at the time of the collision?

Location of other vessels
There were other vessels in the area that observed debris from the wreckage, particularly the day after the sinking. What information can be learned from their accounts?

Accounts of the survivors and where they were picked up
There are two equations that must match: the vessel traveling to the south and the northward drift of the debris and wreckage. How far offshore can the wreckage be and still end up in the Strait of Juan de Fuca?

The Rockfish probability area defined by “Re-Nav” navigation analysis. The wreck was located in this region.

How this ship was located

Rockfish, Inc. completed the analysis described above. This resulted in a large search area, approximately 13 x 26 miles. As part of the discovery process, Rockfish conducted dozens of interviews of commercial fishermen to see what they may have recovered in their bottom trawling nets. More importantly, Rockfish was able to combine fishermen track data, showing where they dragged their nets on the bottom. This led to a much reduced search area.

The areas that were heavily fished, except for the “hangs” ie net-fouling bottom obstructions, could be eliminated. Occasionally, fishermen would find coal in their nets. Chemical analysis of this coal led to the conclusion it was from a mine owned by Goodall, Nelson, and Perkins, owners of the Pacific. Tracking down the origin of the source of the coal in the fishermen’s nets was difficult, but over time, nearly the entire probability area was eliminated, as well as numerous fishermen hangs. Eventually, a very small area (1 x 2 miles) was identified because all of the clues led to the conclusion that the wreck was in this area. The first time this area was searched, only one target was located, but it was initially dismissed as seafloor geologic material. Post-survey, closer examination of this target led to the discovery of the ship.