AT&T wants to stop providing traditional landline service in California, a move that could leave many customers in rural areas like West Marin with limited communications options—or perhaps none at all—during emergencies.

The company cannot implement its plan without approval from the California Public Utilities Commission, which will hold a series of hearings on the proposal beginning on Feb. 6. 

AT&T began notifying customers of its plans on Jan. 22, raising concerns among residents of rural areas where cell phone service is often unavailable, power outages are frequent, and the risk of wildfire and natural disasters is high.

“There are a lot of places in West Marin that don’t have cell coverage because they are out of range of the cell phone towers,” said Ken Levin, who can’t get a signal from his home in Point Reyes Station. “If there’s a fire or some other emergency, you can’t call emergency services on your cell phone—but I can pick up my landline and make a call.”

The C.P.U.C. requires phone companies to provide traditional landline service to any customer in their service territory if they are the so-called carrier of last resort—typically the largest and sole telecommunications provider in a region. C.O.L.R.s are required to offer basic services such as 911 calls and directory assistance.

AT&T is the C.O.L.R. in West Marin and most of rural California. But the company filed an application to the utilities commission last year requesting to be relieved of its C.O.L.R. obligations. 

AT&T’s request has outraged consumer advocates, who say that telephone companies should not be allowed to back out of their obligation to provide universal telecommunications service.

“For over 100 years, the state, the C.P.U.C. and the federal government have promoted the idea that communities need reliable communication,” said Regina Costa of The Utility Reform Network, an Oakland-based consumer group. “AT&T is saying, ‘We don’t want to do that anymore, so goodbye, good luck and good riddance.’”

In its application to the C.P.U.C., the company argues that expanding cellular and broadband networks have rendered the copper-based network obsolete. It maintains that the vast majority of its clients have access to alternative services.

“We are simply seeking relief from very old regulatory obligations that require us to keep investing and maintaining a network that fewer than 7 percent of our customers use,” said Chris Collins, an AT&T spokesman. “We are committed to bringing more modern services to California that the public needs and wants.”

Yet Ms. Costa said the upgraded broadband networks have yet to be installed in many rural regions—and they can’t be relied upon during power outages. “With your basic copper phone, it will work in a power outage, and you can guarantee it,” she said.

The Utility Reform Network is one of several consumer groups that have urged the C.P.U.C. to reject AT&T’s application. Harriet Barlow, a Point Reyes Station resident who relies on a landline, hopes their challenge succeeds.

“We bought a landline when we first moved here seven years ago precisely because we knew we were moving to an area susceptible to earthquakes, serious weather and wildfires,” she said. “We wanted the phone as a safety measure. We were sold this line with the certainty that it would be there for us.”

According to a statement on the C.P.U.C. website, AT&T would continue providing landline service to existing customers for six months if its application is approved. After that, customers would be encouraged to switch to cell service or rely on internet calling services.

“We can assume that they’re probably going to stop providing service as soon as is feasible for them,” said Tracy Rhine, a spokeswoman for Rural County Representatives of California. “This is something AT&T has wanted to do for a long time.”

In its filings, AT&T claims that roughly 1,400 of its 1 million landline customers don’t have access to alternative services—but that none would be left without coverage. But Ms. Rhine said that calculation excludes many whose cell reception is spotty to non-existent—and the company has already outlined a streamlined process for shedding those customers.

“This would be devastating to the 40 rural counties that we represent,” Ms. Rhine said. “Most of them rely on landline technology to get evacuation orders for emergency responses.”

Later this year, an administrative law judge will hear the case and recommend a decision to the commission. The agency’s website is quickly filling up with pleas from angry customers.

“Don’t let them abandon us, their loyal and long-paying customers,” Moses Berkson of Bolinas wrote.

For more information or to submit a comment, go to http://tinyurl.com/Landline-Comment