Drilling began yesterday to replace an underwater damaged cable that provides power from Edgartown to Chappaquiddick. Construction is expected to last until mid December.

A small group gathered at the drilling point outside of Soft as a Grape on Dock street, waiting for the drilling to begin. Dock street is closed to cars at the intersection of Kelley street, and Daggett street has been converted to a two-way street to accommodate loading and unloading of passenger cars.

The 20-foot drill will go 30 feet below the water in a v-shape, deepest in the middle of the channel, and up to the other side over the next few days. Next the hole will be enlarged and filled with drilling mud.

The conduit that will hold the cable is being fused on Chappaquiddick now, to be inserted when the hole is complete.

“There are a lot of variables doing this,” project manager for Bay State Piping Company, David Scott, said yesterday afternoon. “We don’t know what soils there are, there are risks of obstructions.

“It’s a fairly sophisticated process. We have a guidance system on the drill head and we’ll be monitoring the position at all times,” Mr. Scott said.

Comcast is negotiating with NStar to bring cable and Internet service to Chappaquiddick as a result of NStar’s work under the channel, but Mr. Scott said he had no further information about the agreement.