Without current safeguards, offshore windmills a threat to archeology 

An archeologist at Saturday’s Historic Preservation Conference warned that sea level change since the last ice age means that, without the archeological review process that her organization is part of, offshore turbine installation could disturb ancient sites before archeologists get a chance to study them.

The comments garnered an angry response from a representative of Deepwater Wind, the company that is hoping to install windmills off the south shore of Block Island in the first-such state project. Deepwater Wind Chief Operating Officer Paul Rich stood up and called her words about turbines “inflammatory, as well as untrue.”

Rhode Island Historic Preservation and Heritage Commission (RIHPHC) Senior Archeologist Charlotte Taylor told an audience of about 60 gathered at St. Andrew’s for the conference about the archeological review process turbines go through. She warned that without these existing safeguards, both turbine installations and the laying of marine cable could disturb archeological sites. She showed a graphic of a cable-laying device, which she said would “destroy any archeological site in its path.”

RIHPHC Deputy Director Rick Greenwood quickly cut short Rich’s remarks and moved discussion on; however, after the session was finished, Rich and Taylor engaged in a heated discussion.

As part of her presentation, Taylor discussed the submarine cables that would run between the turbines and Block Island and said they could cross Manissean Indian sites. She also mentioned the many shipwrecks that dot the Block Island coast.

Deepwater Wind’s Block Island liaison, Bryan Wilson, said in a later interview that the technology planned to lay the Block Island cable is “much less invasive” than the method presented at the conference. Wilson said that a “jet-plow” would be employed, which would disturb only a narrow path of relatively young sediment, rather than the deeper, more archeologically significant soil.

Wilson said that Deepwater is siting its turbines and cable path to avoid “all marine features, whether they are commercial, archeological or biological.” He said Deepwater has also taken eight core samples from the turbine site, proposed for three miles off the southeast coast of the island. However, Deepwater will not be doing an in-depth study until an appeal, currently pending in State Supreme Court, is settled. The appeal seeks to block Deepwater’s project, citing fears that it will raise power rates in the state.

“We are still in the preplanning stages,” Wilson said. “We are not going to be doing an expensive survey until we have some relative security that it can go forward.”

Greenwood also gave a talk on determining if a turbine has a negative visual impact on historic districts and landmarks. He said the commission tried to base its recommendations on “widely excepted subjective values.”

By the commission’s standards, wind turbines are permissible in historic areas if they are not “visually dominant.” However, the commission judges the impact of the turbine based on its placement and size relative to historic buildings.

Greenwood used the North Light, where a small turbine was erected next to the historic lighthouse, as an example of how a small turbine can have minimal visual impact.

He also showed a map of Block Island with the areas where the Deepwater turbines could be seen. Along with the southeast side, the turbines were visible from sections of the historic district, Beacon Hill and Clay Head.

While much of the session was devoted to mitigating the visual impact of large turbines, Greenwood recognized the role of alternative energy in preserving historic landmarks. He pointed to environmental problems arising from fossil fuels, such as acid rain, which can destroy historic landmarks. In the end Greenwood said it was the RIHPHC goal to improve turbine proposals to preserve historic resources while allowing for the development of renewable energy.

The Cape Wind project, which would be visible from a number of historical districts and landmarks, was given approval by Secretary of the Interior Ken Salazar one year ago. Virginia Adams, senior architectural historian at the Public Archaeology Laboratory, discussed the process that project went through in terms of visual impact on Nantucket Sound.

The Salazar decision came without an agreement with the Massachusetts Advisory Council of Historic Preservation, the counterpart to the RIHPHC. When asked whether a similar decision could override viewshed concerns with the Block Island project, Adams said that it was possible.