NSTAR begins work on new mainland extension cord

NSTAR begins work on new mainland extension cord

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One of two barges that will assist with the laying of a new cable from Falmouth, in the background, to Martha's Vineyard was anchored off West Chop Monday. — Photo by Nelson Sigelman

Work by marine contractors on a joint project for utility giants NSTAR and Comcast to run a new undersea cable from Falmouth to Martha’s Vineyard has begun on the Island side of Vineyard Sound.

A large work barge anchored in Vineyard Haven harbor arrived in preparation for the start of shoreside horizontal directional drilling (HDD) from the land. The plan is to install a conduit under the seabed in order to avoid disruption of fragile barrier beaches and sea grass beds where the cable comes ashore.

Once completed, the 4.5-mile cable, about 5.5 inches in diameter, will leave the mainland near Mill Road in East Falmouth and come ashore at a utility right of way in the Mink Meadows area of West Chop where an existing cable now comes ashore.

NSTAR, the public power utility that supplies electricity to Martha’s Vineyard, and Comcast are footing the bill for the $20 million project. The hybrid cable will replace a failed electric cable and carry fiber-optic strands for Comcast, which wanted a backup for its existing fiber optic link through which it provides television and communications services.

In a story that aired December 24 on NPR radio station WCAI (Tunneling a cable to Martha’s Vineyard, 30 feet at a time), reporter Brian Morris described the work in process on the Falmouth side where it originates in at the corner of Surf Drive and Mill Road. At the work site in December, NSTAR Project manager Coleman Geary explained the complex process. “What we’re doing here is horizontally drilling a 2,900-foot hole from here out to a barge out in the Sound,” he said, “so that the cable can run under all the critical habitat that’s out here — the eelgrass, the clam beds, everything else — so it can go out without having to do any environmental impact at all.”

The cable is six inches in diameter, and contains three wires and two fiber-optic cables, all inside a six-inch shell. A barge anchored in Vineyard Sound has a winch that will pull the cable through a pipe from the shore out to the Sound. From there, said Mr. Geary, the cable will be laid across the bottom of Sound. “When the cable is installed, a barge will haul a plow across the bottom that’ll cut a slot and lay the cable in.”

The environmental impact of that cutting will be low, and the sand and currents will quickly erase any signs of disturbance. Burying the cable below the bottom, Mr. Geary said, will prevent the cable from moving during storms or being dragged by a boat anchor.

Push and pull

In a telephone conversation Friday with The Times, Mr. Geary described the work about to begin on the Vineyard side of the project.

Two barges will be moved into place as the project proceeds. One, an environmental barge, will be anchored over the exit point of the drill. “That barge will be anchored offshore for the purpose of recovering any mud that manages to leak out of the pilot hole,” Mr. Geary said. “The other barge, the one that was in the harbor, will be used to tension the drill string when they are expanding the hole. The original pilot hole goes in at 6 inches and then they do another process where they expand that to 18 inches. And during that period of time they not only have to push it with the drill on the shore but they have to pull it with a winch on the barge.”

The drilling equipment is now being set up about a quarter mile west of the West Chop flagpole on the beach. NStar spokesman Michael Durand said about half of the equipment needed has been placed on protective mats. More environmental controls will be put in place and the entire work site will be surrounded with a security and safety fence, he said. The barge will not be needed right away but because the process of anchoring it is quite complicated it needs to be positioned early.

Work on the Falmouth side to install the conduit was completed December 31, following about a two-week delay after the drill crew ran into some unexpected rock formations. The actual cable will not be installed until April, Mr. Geary said.

Replacement cable

There are now four submarine cables from the mainland to the Island: the 91 and 97 lines come ashore at Mink Meadows; the 75 and 99 lines come ashore at Eastville in Oak Bluffs. The 75 line has failed and cannot be repaired. The 99 line is operating now, but it has failed and been repaired several times.

Of the two West Chop cables, the older one has failed and been repaired six times. A cable installed in 1990 is now operating. It has never failed. If it did, the Island would be left with much less electrical capacity than is required at peak use times.

The failure of undersea cables, combined with increasing demand for power, has forced NSTAR to bring powerful diesel generators to the Island, to supplement the power transported by electric cable. Each year, the generators have seen increasing use.

Last July, one of the three working NSTAR cables failed. As a result, NSTAR added eight temporary generators to the five permanent diesel generators owned by NRG Energy that currently supplementary power provided by NSTAR cables during the summer months. The cable was repaired in August.

A crew of approximately 25 have been working in the frigid conditions to replace the failed 75 line with a new 75 line, which will come ashore at Mink Meadows, and increase the reliability of the power supply.

“You need four cables feeding Martha’s Vineyard,” Mr. Geary said. “If you don’t have four, any time you have a cable out of service you have to rely on the generators to carry the balance. And during the summer, you have to rely on supplemental generators.”

Mr. Geary said the new cable should eliminate the need for supplemental generators.

Two of the existing three cables can handle up to 13 megawatts (MW) each and one can handle 17 MW, Mr. Geary said. The new cable will handle 19 MW.

He said there are many environmental reasons why the new 75 line was moved from Oak Bluffs to Tisbury. The move meant the utility needed to beef up its utility pole infrastructure to bring the power ashore and distribute it around the Island. “The driver behind those bigger poles and thicker wire is to be able to move that capacity over to where the load is,” Mr. Geary said, primarily down-Island.

NSTAR expects to throw the switch on the new cable in early May.

“Our goal is to get the job done and do it in a manner that doesn’t inconvenience anybody,” Mr. Geary said.


  1. With about 15,000 houses on the vineyard , that works out to about $1,300
    per household.

    1. Households are not the only power uses….businesses, schools, towns, should perhaps be included. Maybe a “per meter” or “per user” figure would be even more meaningful.

    2. ok, with 17,000 year round residents, That’s about $1,200 per person, when you add in the beautiful power line upgrades we have been noticing lately.
      That’s just for this one line. How much did the pole upgrade cost ?
      Then we have maintenance, generation and distribution charges, etc. etc.
      That local power on the rooftop keeps seeming like a better idea..
      I guess the brown heads should be thanking the greenies for all that power they are not using from the mainland. Nstar might have needed 2 lines, at a higher cost.. I doubt these kinds of upgrades come out of the pockets of the exec’s.
      Imagine that, all those greenies with their solar water heaters , electric panels and new fangled energy efficient light bulbs are actually keeping the cost of electricity down.

  2. I really hope someone other than Comcast is also laying fiber along those conduits so that the Vineyard will have sufficient bandwidth in the future….and maybe even a true broadband competitor.

    1. Why on Earth would you pay for hideously expensive, fiber optic cable for future use out of your own pocket? It’d be like me as a plumber leaving a water heater in your basement, that I paid for, for possible future needs. FYI, Adelphia ended up having to replace all the cable run by Whaling City cable back in the day, because it didn’t meet the specs they paid for when they purchased it. Comcast has had to pay for the Shenanigans Adelphia’s owners pulled. Now, Nstar and Comcast are paying to upgrade OUR infrastructure and your first thought is to complain. Modern America, gotta love it.

      1. I’m not complaining. I am hoping that we have competition which should bring about better service and potentially lower prices. Let’s see…I believe that’s called capitalism which isn’t such a modern concept..

        Laying extra fiber, sometimes called dark fiber, is a good thing because it’s far easier and less expensive to do it now than to go through this entire process again. I can guarantee you that Comcast is laying a lot more fiber strands than it expects to use in the near future.

        Is there some reason you wouldn’t want another ISP on the Island?

        NStar is an entirely different story. They provide distribution which provides the product (electricity) from a variety of different vendors. The same can’t be said for Comcast’s lines.

        1. You’re forgetting that cable companies usually have a contract to serve where they serve because they have to keep the infrastructure maintained and install new. The two new fiber optic cables means we now have triple the fiber from before, IFIRC, the existing fiber is owned by Nstar and leased by Comcast.

          There are other ISPs in the area, check your options, it’s a modern concept called researching before commenting.

          I also remember the rolling blackouts one Summer in the 80s because a cable failed, I’m happy to know it’s being addressed before there’s a problem. The thought of no power during a cold snap is a frightening prospect. We’re learning more and more, a lot of other utilities haven’t been upgrading or even maintaining their lines and the consumer has been paying the price when Mother Nature plays her hand. We’re on a little island and we’ve been getting the latest everything, we should feel fortunate.

          1. Okay, name another ISP on the Island capable of providing consumer service at over 50mbs? How about at 1gbs? That’s what is going to be necessary to be competitive in a few years.

            I’ve done the research…the answer is none.

          2. 1gs? Where do you get that as a consumer? FIOS has been a good option for some. Satellite for others. The answer is, you’re on an island, count your blessings you’re not using dial up. I hate to break it to you, but, it’s kind of hard to have competition when you’re talking about lines on a pole. Do you expect Cox cable to show up, run their lines, and then try to lowball the competition in such a limited market? Sounds like the stuff of fairy tales. Plus, everyone will post here complaining about how ugly the new sets of lines are.

          3. Do a search on 1gbs internet service you’ll be surprised. Companies like Google are already offering it in cities as are some other companies. It’s also prevalent in a lot of foreign companies. Average internet speeds in the US trail many other countries (I believe we’re 9th).

            FIOS is not offered on Martha’s Vineyard and satellite service can hardly be called broadband as it’s speed is slower that DSL and the latency makes real-time interactive products difficult at best. Wireless could conceivably provide competition, but they still require hard cables for the longer runs.

            Oh, Google is charging $70/month for 1gbs service which is about what Comcast charges for service 1/20th the speed. For some strange reason though…wherever a company like Google has entered a market, the local cable company has also increased its backbone and offered higher speeds at comparable costs (I wonder why?).

            Twenty years ago top internet speeds were about 1/2000th the speed that they are today (56k)

            As for the part about living on the Island that’s why I made the original post. We, more than many other locations are going to need the internet.

            They are laying cable. This is the opportunity to lay additional fiber lines to support increased bandwidth and by doing it now we would be lowering the hurdle to another company making the investment.

            Bandwidth is going to become increasingly important in the coming years as resources, financial, educational, medical and the like continue to migrate to the internet and evolve.

            Depending on a single company with little or no competition will put us and our children at a huge disadvantage.

            As for people complaining about additional lines on a pole…there are people here that would complain about indoor plumbing.

            So, to go back to my original post. I hope that additional fiber optic lines are being put in place to support our needs down the road.

          4. You are correct that the new poles are inadequate and ugly, as well as a hazard to motorist, likely to be destroyed in a cat 3 or better hurricane and not very cheap. They will also require tree trimming on an ongoing basis.
            I think if you are going to upgrade the infrastructure, you should not mickey mouse it.. State of the art fiber optics underground would have been much cheaper in the long run.