The wildfires surging through the woods of Napa and Sonoma counties are cutting off residents’ wireless links to one another and to the outside world.
Cellular voice, text and Internet coverage across much of the Napa Valley has been stopped or impaired since the fires erupted Sunday night, representatives of the four major wireless carriers confirmed Tuesday.
Spreading flames cut a fiber-optic cable that passes data and voice calls to and from several Napa-area cellular towers, according to John Votava, a spokesman for Sprint. Calls, text messages and Web traffic pass from handsets to the towers, through cables and on to switches called local exchange carriers, which route traffic to other users.
The number of cell transmitters disabled or destroyed, and which companies use them, was not immediately clear as of Tuesday afternoon. One tower may be mounted with cell equipment for two or more carriers.
Spokespeople for Sprint, Verizon Wireless, AT&T Mobility and T-Mobile US Inc. said their repair crews are unable to tend to affected towers because of extensive power failures caused by the fires, as well as roadblocks cutting off areas under mandatory evacuation orders.
Sprint repair teams do not expect to receive clearance by Cal Fire to enter fire evacuation zones until Wednesday morning at the earliest, according to Votava, who said crews from the company began arriving in the North Bay on Monday to be ready to work once cleared to do so.
As of late Tuesday afternoon, no containment had been reported for the Atlas, Tubbs or Partrick fires burning in different parts of the county.
Carriers reported bringing mobile cell transmitters to fire-stricken areas, where the wheeled devices allow fire agencies to communicate and provide them with data network support. Truck-mounted transmitters connect to cell networks by satellite and do not need a land-based power line, AT&T spokesman Leland Kim said in a press release.
Verizon is providing public safety workers with mobile Wi-Fi and charging stations at the Napa Valley Expo, and has done the same in Santa Rosa to support those evacuated from Sonoma County hospitals, said spokeswoman Heidi Flato. The carrier also will not charge for mobile data through the end of Thursday.
Sprint and its sister services Boost Mobile and Virgin Mobile are waiving voice, data and text overage fees through Thursday for areas affected by the Bay Area fires, according to Votava.