SALEM — It is technically feasible to install high-voltage electrical cables under Salem Harbor, but an underwater project of that scope would cost about $110 million, according to an engineering report released yesterday by National Grid.
The underwater route would be “double the cost” of a proposed land route, the utility said in a recent letter to city councilors.
National Grid released the engineering report in response to a protest by a number of neighbors and businesses that culminated this month with a City Council vote to put a nonbinding ballot question seeking support for the harbor route before voters in November.
Opponents contend the planned land route would disrupt neighborhoods and the central business district, would hurt businesses and could be avoided by using an underwater construction technology that National Grid has used on other projects.
The utility counters that the state’s Energy Facilities Siting Board, which will review the project, would not approve horizontal directional drilling — the technology that would be used to go under Salem Harbor — for this project because it does not meet three key criteria: least cost, least environmental impact and best reliability.
National Grid must replace large underground cables that run from a substation on Fort Avenue next to Salem Harbor Station to another substation on Canal Street. The company has proposed a route that would go down Fort Avenue and Forrester Street, past Salem Common, down Hawthorne Boulevard and Congress Street, through The Point neighborhood and over to Canal Street.
While some past and present city councilors oppose the land route, other elected officials have been more cautious or have pointed out problems with going under the harbor. State Rep. John Keenan, chairman of the Joint Committee on Telecommunications, Utilities and Energy, has noted that it would be much more expensive, a cost that he said would be passed on to rate-payers.