Hurricane Ida knocked out several 911 systems in and around New Orleans on Monday.
Meanwhile, many AT&T customers couldn't complete calls due to 'widespread outages.'
Residents singled out AT&T's cell service failures on social media, The Washington Post reported.
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Social-media users blamed mobile provider AT&T for widespread cell service issues during Hurricane Ida, saying they were unable to contact friends and family impacted by the storm.
In addition to issues with personal calls, several 911 dispatch centers in and around New Orleans crashed as Ida made landfall on Monday, leaving thousands of residents and concerned family members scrambling for emergency help.
One user tweeted Monday, "Do better AT&T! I have reached every person in New Orleans who has Verizon. My mother is completely unreachable as well as friends who have AT&T. No one knows if any of them are safe!"
On Facebook, users requested help from the United Cajun Army, a volunteer group that organizes boat rescues.
"My mom was there at 1:30 am with no power. Haven't heard from her since. Her phone provider is out and no wifi without power," one user commented on the group's Facebook page. "If someone happens to be out that way, please see if Ms. Billie is there, she wasn't able to go home bc of a tree blocking her neighborhood."
New 911 dispatch technology, part of contract with AT&T, was set to be installed early next year to replace the "antiquated" system that failed during Monday's power outages and flooding, The Washington Post reported. One district official told the Post that the technology wasn't replaced years ago in part because "it's expensive."
AT&T is the provider for all 911 call centers in Louisiana, Tyrell Morris, the executive director of The Orleans Parish Communication District, told the Post.
"Hurricane Ida has caused significant impacts to our network in Louisiana from the massive power outages and storm damage," AT&T announced in a network update. "Our Louisiana wireless network is operating at 60% of normal and we have significant outages in New Orleans and Baton Rouge due to power outages, flooding, and storm damage."
In comparison, T-Mobile said in its most recent statement released Monday that the network is about 70% operational across Louisiana and Alabama.
As of this morning, AT&T's wireless network in Louisiana is reported to be 85% operational.
Verizon said 85% of the network's cell sites that were in the path of the storm are currently in service. The company did not respond to Insider's request for Monday's network performance, making it difficult to accurately compare how the three networks held up during Monday's storm.
"In downtown New Orleans and Baton Rouge, there are a few scattered cell sites experiencing issues, but the majority of Verizon customers are experiencing minimal service interruptions thanks to overlapping coverage," Verizon spokesperson Karen Schulz told Insider.
AT&T, Verizon, and T-mobile are waiving data limits for customers who live in areas impacted by Hurricane Ida.
"Our wireless network in Alabama is operating normally and Mississippi is experiencing minimal impacts to wireless service. We will continue to make repairs as quickly and safely as possible in order to keep our customers connected," AT&T wrote in a statement.
"All of our wireline facilities are online, although many are running on backup power at this time. We are deploying additional generators and refueling them as needed ... To aid in the recovery efforts, we have 13 mobile satellite cell towers on-air and have additional assets on the way to areas impacted by the storm."