While it is possible to lay high-voltage transmission cables under Salem Harbor, it would be a "high-risk" installation, expensive to construct, harmful to the environment and difficult to maintain, according to a feasibility study commissioned by National Grid.
The giant utility announced its findings last week at a private meeting at the Hawthorne Hotel with downtown business owners and neighbors, who are concerned about the impact of a two-year construction project through the downtown and are lobbying for an alternative route.
After witnessing the delays and problems encountered by the current state highway project on Bridge Street, some are worried that an even larger National Grid project could virtually shut down a section of the city at the height of the tourism season.
A neighborhood group urged National Grid to consider going under the harbor and was disappointed to learn that the utility, after hiring a consultant to do the study, has rejected the idea.
Some are even asking for a peer review and to see the full report.
"They're saying that's out of the question," said George Carey, the owner of Finz, a Pickering Wharf restaurant, and former president of the Salem Chamber of Commerce. "They've done a study but don't want to release it ..."
Carey said the downtown community "wants to exhaust every possible question" on the water route before accepting a land alternative.
National Grid investigated a technology known as "horizontal directional drilling," or drilling down and under the harbor.
Last week, it released an executive summary of its study, which concluded that the underwater route is "a high-risk installation, has increased environmental impact, has increased project costs, and poses adverse long-term maintenance/reliability issues. ... As such, this project alternative has been deferred from further analysis and consideration."
As for releasing its full study, National Grid spokeswoman Charlotte McCormack said the company "has already willingly provided the community with a copy of the executive summary from the commissioned report, and we feel that this voluntary action fulfills our commitment to research horizontal directional drilling and share those research results with the community."
Due to the scope of the future work, National Grid began meeting with city residents and officials months ago even though it has not announced a timeline for the project.
Construction is not expected to start until 2014. The possibility of a natural gas plant being built at Salem Harbor Station could delay the start date further.
The utility must replace two transmission lines that run from its substation next to the Salem Harbor Station power plant to another substation on Canal Street.
Both would go through the downtown.
There are two proposed routes. One goes down Derby Street to Canal, which is the current path, and the other would go through the Salem Common area, possibly via Forrester Street, down Hawthorne Boulevard to Congress Street and over to Canal Street.
In its study, National Grid said drilling under the harbor to lay cables would cost $43 million compared to about $28 million for a land route.
Drilling under the harbor also poses additional environmental risks, National Grid said, as does construction of a large platform in the harbor during construction. If there were a problem, locating and repairing a cable failure under the harbor would be time-consuming and costly and could harm marine life, according to the study. The water route also would trigger a complex permitting process.
Some remain skeptical about the utility's findings.
The drilling technology is "used throughout Great Britain and Europe," neighbor Mary Madore said. "I just don't understand why our little harbor is an obstacle."
Chamber Executive Director Rinus Oosthoek thinks a peer review should be considered.
"It's such a major-impact project, it would be good for the city, as well as the business community, to have expertise on our side in a sense — not because we're challenging what National Grid is saying, but just to make sure we're asking the right questions and streamlining the project to ensure there's the least impact possible."
Oosthoek said he has asked Salem State University to do an economic impact study.
While noting that National Grid raised valid issues, state Rep. John Keenan said residents and businesspeople also have legitimate concerns.
"This cannot and will not be another Bridge Street," he said. "It's unacceptable."