Within 48 hours of Hurricane Katrina hitting New Orleans in 2005, 80% of the city was flooded, with some parts under 15 feet of water.
Tens of thousands of residents were stranded and needed rescue.
The recovery effort that followed occurred in an old school environment: many computer systems were flooded, and most had no electricity to power them even if they had remained dry.
As it turns out, the ability to recover without that type of technology may be helping New Orleans right now.
New Orleans ransomware attack and state of emergency
The mayor of New Orleans declared a state of emergency over the weekend because of a ransomware attack on city systems.
StateScoop summarizes the real-world impact of the cyberattack, which involved a sudden shutdown of 4,000 computers and servers:
"New Orleans' official websites remained offline through Monday morning, and several more services were still affected. Municipal courthouses were closed Monday, and the city's Healthcare for the Homeless service was unable to see patients because workers cannot access electronic health files, according to Mayor LaToya Cantrell's office.
Emergency services, including the city's 911 line, were mostly unaffected, but some agencies have opened Gmail accounts to handle non-emergency requests while the city's email server is offline."
How did hackers start the New Orleans ransomware attack?
At a press conference over the weekend, New Orleans State Chief Information Officer Kim LaGrue said the city's IT team noticed a sudden increase in phishing emails aimed at their systems starting at 5 a.m. Friday, with reports of suspicious activity picking up as employees arrived around 8 a.m.
By 11 a.m., the IT team was going office to office to make sure everything was shut down.
The City's CIO said it had no evidence anyone had clicked or been tricked by the emails, however, credential compromise was the road in for hackers:
"We've never confirmed any credentials were given out," LaGrue said. "But when we look at how our environment was permeated, it was through a compromise of credentials that belong to city employees."
Hurricane Katrina helped prepare New Orleans for cyberattack
Digital news outlet NOLA.com pointed out that robust planning and recovery work that has happened in past disasters was already helping the city continue to serve residents:
"One positive about being a city that has been touched by disasters... is our plans and our activities reflect the fact that we can operate without the internet and without a city network," said Collin Arnold, New Orleans' homeland security director.
However, it appears that working without a computer network has become more difficult since 2005. According to NOLA.com:
"New Orleans Police Department detectives were working on personal computers from home on Monday, shut out of access to some essential law enforcement networks.
Officers couldn't pull up information about license plates, access police reports, run background checks or enter arrest warrants into a national database—at least not through routine electronic channels— after a cyber-attack Friday led officials to flip the kill switch on the city's computer system, law enforcement sources said."
Hurricane Katrina image credit: NASA