The outburst of public fury includes calls for some royal princes and government officials to resign, calling to mind the widespread anger in the US over the Bush administration's ineffective response to hurricane Katrina in 2005.
"This anger has never happened before," says Waleed Abu Al Khair, a human rights lawyer in Jeddah and one of the creators of a Facebook page that has drawn more than 20,000 comments in four days.
The exasperation evident in the comments and in the columns of Saudi newspapers is propelled by widespread Saudi belief that mismanagement and corruption are to blame for Jeddah's lack of adequate storm drainage and sewage systems.
"Good job, mayor!" said a sarcastic comment on the Facebook page titled "Popular Campaign to Save the City of Jeddah." "All these billions, all these contracts.... You have betrayed our trust!"
Other angry citizens, many of them using their real names, posted links to old official announcements of multimillion-dollar spending plans to update Jeddah's infrastructure. Some demanded that officials be put on trial.
"People have been very vocal ... and unafraid because they've seen the worst. They have reached their breaking point," said Reem Asaad, a Jeddah lecturer on finance. "We're fed up living in a city like Jeddah ... where services and infrastructure are poor. We deserve much better."
The city's drainage system was overwhelmed this past Wednesday when a five-hour downpour dumped 3.7 inches of rain on the Red Sea port. Many people were drowned as their cars were swept away and Saudis have asked why police were not on the streets to warn drivers away from dangerously flooded areas.
In addition to the deaths, the floods displaced more than 1,200 families, destroyed an estimated 4,000 vehicles, and caused millions of dollars in property damage, according to local papers.
The floods occurred on the first day of the hajj, the annual pilgrimage to Mecca that draws up to 2 million Muslims from around the world. The entire government, from King Abdullah bin Abdul Aziz on down, was preoccupied with making sure that the pilgrimage went off without a hitch. It did, and early concerns about security disruptions and swine flu outbreaks did not occur, largely because officials had put in months of preparation prior to the hajj.
The unelected Saudi government does sometimes respond to public opinion, especially if it involves basic services. How it will react to the public clamor to uproot official mismanagement and corruption is another matter. In the past, such complaints have not led to any type of public punishment or prosecution.
King Abdullah has ordered monetary compensation and free medical care for displaced families, and the government will also compensate owners of damaged property. The National Guard has been ordered into some neighborhoods to maintain security and assist local civil defense authorities.
Provincial governor Prince Khalid bin Faisal has ordered "an immediate investigation into the drainage network" of Jeddah and a report on the municipality's plans for preventing future floods, the Saudi Gazette reported.
Rasha N. Heszi, spokeswoman for a civic society group called Mwatana, or Citizenship, says she believes the public outcry has "opened the eye of the government" to the fact that "people need to see quick wins" instead of being promised benefits in the long term.
Ms. Heszi's group has been organizing volunteers and distributing donated goods to people in areas hit by the floods. People in one neighborhood were upset, she says, because no relief or rescue officials had yet appeared, probably because most were still working on the pilgrimage.
Mr. Khair, the lawyer, says he intends to file a class action suit against Jeddah's municipality. He does not think any official will be forced to resign, he adds. "In Saudi Arabia, we didn't hear about someone leaving his office."
The attorney says that the Facebook page was a useful alternative because street protests are illegal in the kingdom. The Internet "is the only way. We don't have another way," he says.
The episode has demonstrated "how technology allows people to shout out loud. I have never seen this before in Saudi," says Asaad, the lecturer. Even if people commenting on Facebook "use pseudonyms, it's a start," she adds. "But nowadays, people are using their real names."
Anger has also surfaced in the print media, which has been given more latitude under King Abdullah but remains controlled by the state.
For example, the Saudi Gazette carried a hard-hitting interview with Jeddah's Mayor Adel Faqih that included an unusual display of sarcasm from journalist Abdulaziz Ghazzawi.
When Mr. Faqih was asked why a brand-new underpass at a crucial intersection had filled with water, he replied that the city was "surprised by the floods."
"Surprised?" replied Mr. Ghazzawi. "This is a new project that cost about [$80] million. What surprise are you talking about?"
At the end of the interview, Faqih acknowledged that "at least 70 percent of the city lacks a proper drainage system."