A massive cell phone and landline phone outage caused by a cut fiber-optic cable in Clements cut off 911, ATM and credit card services throughout the Sierra Nevada region on Thursday.

Caltrans District 10 spokesperson Warren Alford said a Caltrans subcontractor from Stockton, Midstate Barrier, Inc., was conducting a paving overlay and guardrail replacement project on Highway 12 in Clements, located in San Joaquin County and at the border of Calaveras County at 1 a.m. Thursday.

While digging approximately five to ten feet underground, crews struck and damaged an AT&T fiber optic cable.

The breakage knocked out cell service, landlines and internet for multiple service providers throughout the Mother Lode, including customers from telecommunications giants Verizon and AT&T.

Ryan Oliver, a spokesperson with AT&T Media Relations, sent an emailed statement at 10:52 a.m. that said “service for some customers in the Sonora and surrounding areas may be affected after a road construction crew damaged our cables while working earlier today. Our team is onsite and working to repair the damage as quickly as possible.”

Heidi Flato, spokesperson for Verizon, said the company leased access to the cable from AT&T to ensure the connectivity of wireless networks in the region.

“Our engineers are working with our vendor partners to resolve this issue quickly,” she said in an emailed statement.

Flato said other telecommunications companies may lease access to the cable, though she did not know the names of any specifically.

Oliver did not return additional requests for comment.

Some Verizon customers visited the store on Mono Way with their bills to ask why their service was disconnected and were met at the door by a security guard who reassured them it was a system problem.

MBI had a valid Underground Service Alert tag, which allows them to conduct infrastructure digging projects, and received clearance from AT&T to work in the area, Alford said.

MBI was either repairing, replacing or installing guardrail when they damaged the cable.

The prime contractor was George Reed, Inc., from Jamestown, Alford said.

Flato explained that the data packages associated with cellular calls are transferred via fiber optic cables to telecommunications central offices and then out to their intended destinations.

Debbie Dills, Sonora Police Department records technician, said the department flipped an emergency switch to reroute 911 calls to the Tuolumne County Sheriff’s Office after 1:30 a.m.

Dills said Thursday morning she did not know if 911 service was down countywide at any point during the outage, which would have made 911 service unavailable.

“Now we are getting calls, we don’t know if we are getting all our calls,” she said.

A mobile “cell tower on wheels” was installed in front of the department by 1:30 p.m. to ensure the service of the non-emergency business lines, which were also cut off during the outage, Sonora Police Chief Turu VanderWiel said.

Sgt. Greg Stark with the Calaveras County Sheriff’s Office said AT&T expected to fully reestablish service at around 9 p.m. Thursday.

He said the outage affected Calaveras County, Alpine County and part of Tuolumne County, and all at approximately the same time.

At about 11:45 a.m. he said the 911 system was operating on an alternative network and emergency services were available.

He said he was unsure if there was a gap in coverage during the outage.

The Sheriff’s Office requested non-emergency reports be made in person at the Calaveras County Sheriff’s Office at 1045 Jeff Tuttle Drive in San Andreas.

The Calaveras County Sheriff’s Office website was down at about 12:15 p.m.

Dills said the Tuolumne County Sheriff’s Office was at one point not receiving any 911 calls before they were rerouted to the Sonora Police Department.

The Sheriff’s Office said some Tuolumne County Sheriff’s Office calls were being taken from the CHP dispatch center in Merced.

Dills said this outage was “completely different” from when the AT&T central office on South Stewart Street was swamped with flood water and 911 emergency service was knocked out countywide on March 6.

This case was more widespread and didn’t involve the central office in Sonora, a network hub for phone calls. On March 6, underground cables connected to the AT&T central office on South Stewart Street were inundated with flood waters and caused the service outage.

“Anytime we do not have 911 service it is a concern. The last outage was due to nature and this one due to damaged line,” the Sheriff’s Office said in an email.

The Sonora Police Department and Tuolumne County Sheriff’s Office transferred 911 service to the Calaveras County Sheriff’s Office dispatch center during the March 6 storm.

In October 2014, suspected vandals cut a fiber-optic line near Sonora and affected the dispatch centers for the Sonora Police Department and the Tuolumne County Sheriff’s Office.

Though the outage has caused some hiccups in the local telecommunications grid, many businesses that do not use alternative telecommunications services, such as Comcast, reported their digital systems were still up and running at about 11:30 a.m.

Both ATMs were down at Bank of America on Stockton Road. Staff told customers they were only able to provide minimal services due to downed internet. The 76 gas station on South Washington Street was also only accepting cash for services.

Gold Country Gas across the street said they did not use AT&T and were completely up and running. Emberz restaurant on South Washington Street also said their credit card machines and phones appeared to be working.

Little Roots Toy Store on South Washington Street was able to provide digital transactions from WiFi, but their phone lines were down.

Adventist Health Sonora said in press release they have established emergency lines. The outage has affected inbound calls, outbound calls and faxes, they said.

Downdetector.com" class="auto" target="_blank">dir="ltr">Downdetector.com, an online site that tracks phone outage reports, indicated there were AT&T outages throughout California, east Texas, Tampa, Chicago, Detroit, Washington D.C., and New York City.

A commenter on the site said before 9 a.m., “ALL service down in and around Murphys, CA. Is there an estimated time where the network will be back up?”

Another commenter from Angels Camp said around 10 a.m. all cell service was down.

Alpine County Undersheriff Spencer Case said the Bear Valley community which borders Calaveras County along Highway 4 was affected by the outage, but not the main office in Markleeville.

He said he was unable to contact the Alpine County Sheriff’s Office public safety station on Thursday.

“It's very inconvenient,” he said.

Case said 911 calls in the Bear Valley area are run through a dispatch center in Douglas County, Nevada. Landlines and internet was reported as down in the area with some cell phones working, he said.

He said it was not reported to him that there was a gap in 911 coverage for the area.

Dills said her personal Verizon phone was working at around 5:30 a.m. when she arrived at the department, but it later experienced issues.

Downdetector.com" class="auto" target="_blank">dir="ltr">Downdetector.com indicated Verizon was also experiencing widespread outages, though by a map analysis, less severe than AT&T.

One commenter on the Verizon page said at about 8 a.m. “Sonora, CA, 95370. Data works, phones do not, waiting on call to schedule surgery.”