CHATHAM – A temporary, less powerful light has been installed at the Chatham Lighthouse while a new generator is installed at the Coast Guard Station.
The installation will require that power to the lighthouse's lamp be cycled on and off, which could damage the sensitive mechanism, according to Senior Chief Ross Comstock. The lower-intensity light is expected to be on at all times while the work is being done, he said, and will remain in place afterwards as a backup.
According to a notice to mariners published Nov. 16 Coast Guard District One, the work will continue through Jan. 10. The process could be completed sooner, Comstock said. If that is the case, a notice will be issued.
The temporary light is less intense than the 2.8 million candlepower main light, which can be seen nearly 28 miles out to sea. Comstock was not certain how far the temporary light could be seen. “I just know the intensity will be a lot less,” he said. He likened the temporary light to “the type of beacon you have on a radio tower.”
While local marine traffic is diminished at this time of year, the lighthouse is still a critical tool for ships passing to the east, even with modern technology like GPS, said Harbormaster Stuart Smith.
“All the mariners do use the lighthouse,” he said. While local fishermen and boaters use the light as a landmark for their return to port, offshore ships use it to verify their position, he said. “It's definitely a handy aid to navigation.”
The temporary light should not pose a problem over the next two months, Smith said.
“They certainly need a new generator,” he added.
The new natural gas-powered generator will replace an old diesel powered generator. The new generator will turn on automatically when the power is disrupted and requires less maintenance. “It's going to be a much lighter logistical load for us,” Comstock said. The new generator will power both the station and the light.
The existing lamps are susceptible to burning out should the power cycle on and off too often, he said, which is one reason why the lighthouse is lit at all times. Much of the mechanism dates from the World War II era, and is one of only four of its kind still in use by the Coast Guard, Comstock said.
“They're quite a beast to maintain,” he commented.
Until electricity was installed in 1939, the light was driven by a clockwork mechanism and powered by kerosene. The previous 1857 Fresnel lens was replaced in 1969 (the Fresnel lens and mechanism is currently at the Atwood House Museum on Stage Harbor Road) and the lamps were upgraded in 1993.
The new generator was supposed to be in place by the fall, but supply chain issues slowed the process, Comstock said. Officials had wanted to make the generator switch in time for the main light to be back in service before winter weather set in.
“It's kind of the hand we've been dealt at this point, so we're trying to make the best of it,” he said.
The Coast Guard Aids to Navigation office in Woods Hole is overseeing the temporary light installation. The agency is also looking into replacing the older portions of the mechanism. “We're at the very, very beginning of discussing that now,” Comstock said.