Deepwater Wind has started a month-long marine survey off the shores of Block Island to collect data about the sea floor and the layers of soil below.
The information collected will help determine the locations for the company’s five-turbine demonstration wind farm – planned for within three miles of the island’s southern coast – and the submarine cables that will connect the wind farm to Block Island and Block Island to the mainland. The survey, performed by Ocean Surveys Incorporated and managed through AECOM, is an important component of permit applications that Deepwater plans to submit to federal and state agencies early next year.
The marine survey, data collection and permit application work will cost more than $5 million and involve the work of more than two dozen scientists and advisers, according to Bryan Wilson, recently named Deepwater’s manager of the Block Island project.
Vessels equipped with a range of sensors to develop a three-dimensional map of the sea floor are beginning to patrol the area of the wind farm and cable routes.
Deepwater Wind will use the survey to assess whether the planned locations of the wind farm and the cables will need to be re-routed if obstacles, such as undersea boulders, shipwrecks, evidence of Native American settlements or sensitive marine habitats, are discovered.
The survey vessel Ocean Explorer has been out for more than a week and will be the first of three ships doing the work. The team aboard uses a multi-beam depth sounder and shallow sub-bottom profiler to determine the depth of the sea floor and the “near surface stratigraphy,” according to a Deepwater Wind statement. It also uses side scan sonar to map the topography of the ocean bottom and a magnetometer to detect submerged metallic objects.
The team consists of up to 12 surveyors at any time, including engineers, marine mammal observers, a marine archaeologist and a member of the Narragansett Indian Tribe. They are working 12-hour shifts on the water for around 21 days to complete the survey.
The inclusion of the Narragansett Tribe to oversee the surveying of the sea floor is something that has never been done in New England, according to archeologist Dave Robinson. During the previous ice age much of the continental shelf, now covered by ocean, was open plains and could have been host to Native American villages.
“Based on oral history we know that there were settlements out where the ocean is now,” said Doug Harris, Tribal Preservation Officer for the Narragansett Nation. “What we are working to do is develop a set of protocols the preserve and protect these sites.”
The sub-bottom profiler reveals sediment layers that have built up below the surface. According to Robinson those can indicate the locations of former settlements.
“When you think about a submarine environment, it is low oxygen and low light. It’s like a fridge, which helps to preserve archeological sites,” said Robinson. “At terrestrial sites you normally find stones and tools, but we now know around 85 percent of what was left behind was organic, which is preserved better at underwater sites.”
So far there have been few significant anomalies identified along the cable route or in the area of the wind farm. The magnetometer registered one contact that was approximately 12 feet long, which Wilson said could be a container box or even a car. Robinson said there has been several sub-bottom features he would like to take a more detailed look at, but that their significance could not yet be determined.
The second vessel to visit the island will use an intermediate sub-bottom profiler, also known as the “boomer,” which employs sound waves to penetrate deep into the seabed to determine the composition of the soil. Wilson says this survey will be more important for the wind farm site, where the jacket structures that will support the turbines will be driven deep into the bottom.
A third vessel will extract core samples at the wind farm site and along the cable routes. Each extraction will sample 10 feet down into the sea bed, and they’ll be taken at 1 kilometer or slightly greater intervals in areas of archeological interest.
During the entire operation a marine mammal observer is present on the boat looking for whales, dolphins, seals and other marine mammals. If any are sighted within 1,000 feet of the boat, all the equipment is shut down for the animals’ safety.
Once the survey is complete, Deepwater will have a three-dimensional image of the sea floor and the layers several meters below. Later this fall, the company will conduct surveys of the planned onshore route of the cables on both Block Island and the area where it will link to the mainland power grid, in Bonnet Shores. Meanwhile wind, avian and bat data from the radar systems and meteorological tower on Block Island will continue to be collected.
Construction Director hired
Deepwater Wind has announced that Robert Billington has been hired as the Construction Project Director for the 5-turbine wind farm.
Billington is a civil engineer and has more than three decades of experience in the oil and gas industries in the United States, Asia, Africa and the Middle East. He will oversee planning, logistics, procurement and management of the project’s assembly and construction.
“Bob brings decades of project management experience to our Block Island team,” Deepwater CEO Bill Moore said in a statement. “His experience and leadership, combined with Bryan’s expanded role on the project, will provide key support as we continue to ramp up the permitting and move into the pre-construction phase of both the Block Island Wind Farm and Block Island Transmission System.”
Wilson also expressed his pleasure at his recent promotion to project manager from Block Island liaison, and optimism for the wind industry’s future.
“I am so excited that I have a fascinating job in this fascinating industry,” Wilson said. “Not only does it allow me to feed my children but will also help this community and in a small way helps the planet as a whole.”
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