In late May, NOAA Ship Rainier officially started her Chatham Strait hydrographic survey project in southeast Alaska. It’s often difficult to imagine the age of many of the depth measurements depicted on Alaskan charts, but this short animation brings it home.
The older picture is U.S. Coast and Geodetic Survey Steamer Patterson and her steam-powered launch Cosmos, surveying Gut Bay in 1897. (The USC&GS is one of NOAA’s predecessor agencies, and a direct predecessor of the Office of Coast Survey.) We juxtaposed Patterson with the Rainier, who is finally able to update the bathymetry — at the exact same location — 116 years later.
The Patterson was under the command of Lt. Cmdr. E.K. Moore, U.S. Navy, while Coast Survey assistants carried out the scientific work. In today’s Coast Survey, a NOAA officer — on the Rainier, it is Cmdr. Richard Brennan — is both commander of the vessel and its chief scientific officer.
The opening to Gut Bay is only about 100 yards wide – and it seems narrower!
“It must have been a real challenge to get the Patterson into this tiny bay in 1897,” Cmdr. Brennan observed. “The opening to the bay is only about 100 yards wide — and seems narrower than that when you are in the middle of it, since the cliffs rise almost vertically on either side.”
“We had the benefit of surveying the very narrow entrance’s seafloor with complete multibeam sonar coverage, and had the use of radar and GPS to inform us about our exact location as we made our way through the incredibly tiny opening into this bay. The Patterson (a steam powered sailing vessel) would have had to do this visually with only a few lead line soundings across the entrance. This must have made for an exciting navigational experience!”
Credit for photo of Rainier: Ensign Damian Manda
NOAA Ship Rainier is due to arrive at its homeport in Newport, Ore., on November 1, completing the ship’s 2012 hydrographic survey season. (Watch Rainier’s progress on NOAA’s Ship Tracker.) This survey season, Rainier departed Newport on May 17 and spent her summer mapping 604 square nautical miles of the ocean floor in Alaska, stretching from Kodiak to the Shumagin Islands, along the Alaskan archipelago.
Rainier has a long 1,769 nautical mile trip back to homeport in Newport, Oregon.
“We completed our last survey on October 24, and began the long 1,769 nautical mile trip back to Oregon,” said Rainier’s commanding officer, Cmdr. Richard Brennan. “The crew put a lot of great effort into their work, some of it under challenging weather conditions.”
Rainier and her four smaller survey vessels use multibeam echo-sounders to measure the depth of the ocean along her path, collecting millions of measurements. More than half of the area surveyed by Rainier this summer had never been surveyed before, leaving large sections of nautical charts void of ocean depth measurements. Commercial shippers, passenger vessels, and fishing fleets need updated charts, which NOAA’s Office of Coast Survey will produce with the multibeam’s precise and accurate measurements.
“Simply put, we have better maps of the moon than of our oceans,” said Rear Adm. Gerd Glang, director of Coast Survey. “Much of our knowledge of U.S. coastal seafloors dates from eras when ocean commerce was more limited, especially in Alaska.”
“At a time when Alaskan waterways are facing unprecedented demands from maritime commerce, Rainier is acquiring the data for navigational charts that are the foundation of the marine transportation system,” Glang explained.
The 231-foot Rainier, one of the most modern and productive hydrographic survey platforms of its type in the world, is named for Mount Rainier, a massive volcanic cone rising 14,410 feet above sea level in Washington. At the time the ship was commissioned, in 1968, vessels of this class were named for geological features. Rainier underwent a major repair period from Nov. 2009 to Jan. 2011, when new systems and equipment were installed.
The ship’s sophisticated seafloor mapping systems allow researchers to acquire hydrographic data that is used to update the nation’s nautical charts. Rainier carries four survey launches that survey shallow, near-shore waters.
Rainier’s scientists, survey technicians, NOAA Corps officers, and crew bring a wide range of navigational and hydrographical expertise to the mission. Rainier has a total complement of 52 people: 12 NOAA Corps commissioned officers, 11 engineers, 14 deck/boatswains, 9 hydrographic survey technicians (in addition to the officers, who are all hydrographers), four stewards, and two electronic technicians.
The ship is part of NOAA’s fleet of research and survey ships operated by NOAA’s Office of Marine and Aviation Operations.
One of Rainier’s projects for 2012 was four surveys in the Shumagin Islands, constituting 2083.2 linear nautical miles of survey lines, and 112.85 square nautical miles of seafloor – most which were never surveyed before.
“But more wonderful than the lore of old men and the lore of books is the secret lore of ocean.”
H.P. Lovecraft, author
The Rainier crew sees the morning fog start to lift from the ship’s anchorage site.
Working on a NOAA ship, discovering ocean secrets, is an enviable job as well as an essential one. One can’t help but envy the scientists and crew of NOAA Ship Rainier as they conduct their hydrographic survey around the Shumagin Islands this month. Their pictures are hauntingly beautiful. And their mission in the midst of the beauty will help to protect the lives of Alaskan fishermen.
This area is experiencing increasing fishing vessel traffic, and the Alaska Fisheries Development Foundation has asked NOAA’s Office of Coast Survey to improve charts used by longline and pot fisheries. Much of the project area has never been adequately surveyed, and large portions of NOAA Chart 16540 have no soundings at all. Fishing vessels need to know ocean depths, and the presence of underwater rocks and other hazards, to stay safe during operations.
In response to the need of local fisheries, Coast Survey will use Rainier’s modern multibeam echo sounder bathymetry to create accurate charts. In addition to acquiring new bathymetry data, Rainier is verifying 2009 data acquired by airborne bathymetric LiDAR from near shore areas around the islands.
Rainier’s survey boats set out at first light to take advantage of a “negative tide” to map the shoreline and its many rocks and hazards. Many rocks that would lie just below the surface during a normal tide range will be exposed and visible during a negative tide.
Rainier is currently surveying the areas outlined in blue. Note the lack of charted soundings (water depth measurements) in the survey area.