Tonga tsunami surge into the Berkeley Marina
On Jan. 15, seawater from a tsunami surged into the Berkeley Marina following an underwater volcano eruption in Tonga. Credit: Jacqueline Bott, California Geological Survey

The city of Berkeley communicated sooner and more broadly than all of its East Bay neighbors to warn the public Jan. 15 about the Tonga tsunami as it approached.

Was the execution of its messaging perfect? It was not. And the city has already begun debriefing and compiling lessons learned.

But, when stacked up against how other local agencies moved to notify their communities last weekend, there is reason for optimism when it comes to Berkeley’s approach to impending disaster.

In recent days, Berkeleyside painstakingly reviewed, to the greatest extent possible, all of the emergency notifications local agencies put out Jan. 15 as the tsunami neared the East Bay. Most of these agencies use AC Alert or Nixle, or a combination of the two systems, to push out text and email alerts to their communities.

On the day of the tsunami, Berkeley was the very first city in Alameda County to begin publishing alerts. It also put out more alerts than any other agency.

Most importantly, Berkeley also followed the latest state guidance when it ordered mandatory evacuations in the tsunami hazard zone; it was one of just a few local agencies to do so.

Rick Wilson, who runs the Tsunami Unit of the California Geological Survey, said Berkeley’s decision to evacuate its marina was in line with state data: “That’s a good thing. Especially in this particular event. Tsunamis can be tricky. They act differently in different locations.”

Some jurisdictions — Alameda County, Emeryville and the city of Alameda — put out one-off notices that did not reference mandatory evacuations. Oakland and Richmond do not appear to have put out any notices at all.

What might Berkeley face in a worst-case tsunami? See the local hazard map.

Those disparate responses cannot be explained by substantially differing risk levels. State experts like Wilson say “sizeable areas” of Alameda, Oakland and Berkeley “could be flooded up to an 18-foot elevation” in a worst-case tsunami event.

The extraordinary circumstances and mish-mash of approaches by authorities last weekend left many members of the public confused and, for a period of time, perhaps more alarmed than they needed to be. An unfortunate word choice early in the day may also have contributed to some of the tumult.

Here’s a close look at how the day unfolded.

‘Get out of your boat and off the docks now’

After the Tonga eruption on Jan. 15, the National Weather Service (NWS) issued a tsunami advisory at 5:27 a.m. for the entire California coastline and beyond “until further notice.” An NWS email about the advisory in Alameda County read: “If you are located in this coastal area, move off the beach and out of harbors and marinas.” Similar NWS emails went out hourly until the tsunami advisory was lifted in the Bay Area at nearly 8 p.m.

The city evacuated more than 100 people from their boats in Zone BER-E034 last weekend. Do you know your evacuation zone? Find it on Zonehaven.

At about 7 a.m., a local resident alerted Berkeleyside that police were going “Code 3” — with lights and sirens — to the Berkeley Marina. Officers blocked the roads into the waterfront and began going door to door on the docks to tell residents living on boats to come ashore. More than 100 people were ultimately evacuated.

At about the same time, the city of Berkeley began to send out emergency notifications. These messages included four AC Alerts targeting marina residents and businesses, and three Nixle alerts to the broader community.

Folks with landlines who are within the evacuation zone and signed up for AC Alerts got phone calls about the evacuation order, too, the city said. The AC Alert messages were also posted on Alameda County Office of Emergency Services Twitter and Facebook accounts; it’s unclear how many Berkeley residents routinely monitor those pages, which appear to have a limited following.

Berkeley uses both notification systems, AC Alert and Nixle, for different purposes. This has led to some confusion. The Berkeley Police Department alone uses the Nixle system, but sometimes it sends messages on behalf of BFD. That’s what happened on the day of the tsunami. 

The Berkeley Fire Department and other city staff use AC Alert, a newer system that has shifted, in both ownership and scope, since its adoption by the city in 2017. That has also led to some head-scratching. Not long ago, the city asked community members to sign up for both systems so they don’t miss key messaging.

In its first message last weekend, Berkeley targeted people who live and work in the marina to give them as much time as possible to evacuate. That’s Evacuation Zone BER-E034 in Berkeley’s Zonehaven system, which the city launched just last year amid wildfire season.

“People in Berkeley Marina, GET OUT OF YOUR BOAT AND OFF THE DOCKS NOW,” read the first message, sent via AC Alert at 7:03 a.m. “EVACUATION ORDER is due to a tsunami that is scheduled to arrive in Berkeley at 8:10 am. 1-2 feet waves possible, carrying dangerous energy that can damage boats and docks. See tsunami.gov.“

The city dispatched police, firefighters, parking enforcement officers and staff from its Parks Recreation & Waterfront department to aid in the marina evacuations, the city told Berkeleyside. It made sure phones were attended throughout the day in the waterfront office. City staff also “made personal calls to Marina berthers to ensure they had evacuated,” the city said. “This layered, very personal outreach reflected the very high level of concern to help those who might be affected and address any questions that might arise.”

Warning or advisory? With tsunami alerts, it makes a difference

The rest of Berkeley — the more than 20,000 people who are signed up for BPD’s Nixle messages, at any rate — woke to a 7:14 a.m. text and email from the police department about the mandatory evacuation: “People living in the Marina or the area of need to evacuate immediately,” the Nixle alert said. 

The message said the Berkeley Fire Department had ordered a mandatory evacuation for marina residents and “those living in the area.” The vagueness of the potentially impacted geography — and the broadness of the recipient list — left some community members wondering if they needed to worry. The Nixle message also noted an “Extraordinary threat to life or property” requiring immediate action.

The message said 2- to 3-foot waves were expected around 7:30 a.m. and described the notification as a “warning.” That seemingly simple word choice may have had ripple effects that extended throughout the county. 

The Google evacuation notice. (Click the image to view it larger.)

It didn’t help matters that, around this time, Google also sent a push alert to Android users highlighting the need for immediate evacuation. It included the text of the Nixle alert but also featured a map — credited to BPD — that showed the entire city of Berkeley as the “affected area.” BPD had not used that map in its alert.

“I got this so I just read the first line and looked at the map and drove up Marin Ave.,” one community member wrote on Twitter. “The first notice was vague enough that my neighbors are all up and confirming that actually we’re fine,” another replied. (Google did not respond to a Berkeleyside request for comment.)

Throughout the day, the Bay Area branch of the National Weather Service (NWS Bay Area) provided timely, reliable alerts on Twitter.

“The arriving tsunami will come in pulses of surging water levels onto and off of the coast, similar to ‘high tide’. Do not expect to identify these arriving pulses by large cresting waves/surf,” the agency posted at 8:39 a.m. “These water level surges can overwhelm and overtake people and pull them out to sea.”

In fact, people who had tuned into NWS Bay Area on Twitter were likely far ahead of the curve. At 3:34 a.m., the agency tweeted that the National Tsunami Warning Center was analyzing post-eruption data to determine the tsunami threat to California and other places. At 4:55 a.m., it tweeted word of the tsunami advisory. That was followed by more tsunami advisory tweets with updated weather forecasts as they became available.

At 7:26 a.m., NWS Bay Area took a moment to remind people about the difference between a tsunami advisory and the other alert levels.

As defined by the National Tsunami Warning Center, and perhaps unbeknownst to many, the highest possible tsunami alert is called a warning. That signals imminent danger with a seawater surge of more than 3 feet expected. The direction is to get to high ground or inland immediately due to flooding and other dangerous conditions.

The next level down is an advisory — what was actually in effect throughout California after the Tonga tsunami. People are advised to stay out of the water and away from shore due to strong currents and dangerous waves. A surge of 1-3 feet is expected. Beneath that is the “watch” alert, where a tsunami is only “possible” and people are advised to “prepare to take action.”

NWS Bay Area told Berkeleyside that there is often confusion around these terms because they have both colloquial and technical definitions. That’s especially true for an occurrence as rare as a tsunami, and also why the agency tweets about the scale.

“Around the time things were starting Saturday, we got some social media chatter like, what does this mean? What should we do?” NWS Bay Area meteorologist Sean Miller told Berkeleyside. “It’s the kind of thing where, whenever we have any kind of high-impact event, we typically do that anyway.”

In the inner East Bay, only Berkeley and Albany announced tsunami evacuations

Meanwhile, Alameda County was a full 35 minutes behind Berkeley with its single, brief AC Alert of the day at 7:38 a.m.: “​​Due to Tsunami at Along [sic] the coastal regions of Alameda County, be advised of potential rising water. The NOAA has issued a Tsunami warning for the entire west coast with potential impacts around 8 AM.” 

That message repeated the confusing word — “warning” — and perhaps extended the haze by including the graphic (which appears in the tweet above) that defines the key alert types authorities use during tsunamis. One-off messages from UC Berkeley and Emeryville PD also described the emergency notification as a “tsunami warning.” 

“Waves and strong currents are expected,” the 7:35 a.m. UC Berkeley WarnMe message said. In the message, UC Berkeley said Berkeley PD had issued a mandatory evacuation order in the waterfront: “People living in the Marina area need to evacuate immediately.” 

The 7:56 a.m. Emeryville Nixle message made no mention of evacuations and urged those seeking additional information to “please visit the National Weather Service website.” No link to that website was provided.

“The National Weather Service issued a Tsunami warning for the Emeryville coastline area to include the Emeryville Marina,” the alert said, telling community members to “Take necessary safety precautions” because “one foot to two feet waves are possible.”

“This warning is in effect until 9:00 am today,” Emeryville advised. In fact, authorities had set no end-time for the tsunami advisory.

Oakland, Alameda and Emeryville include substantial tsunami hazard zones but did not call for evacuations last weekend. Credit: State of California

The city of Alameda did not put out its AC Alert until just before 9 a.m.: “This is an advisory for potential rising water due to the tsunami along the coastal regions of Alameda County. A tsunami warning has been issued for the entire west coast with waves arriving in pulses throughout the day. Avoid venturing onto the immediate coastline today.” Again, a repeat of the word “warning” and no mention of evacuations. 

On Twitter, multiple Berkeleyside readers pointed out the problem of the warning-vs-advisory terminology: “Lots of confusion about the severity this morning,” wrote Stefan Lasiewski. “In reality, our area doesn’t face many severe threats and thus the operators don’t have much real world practice. The tools & procedures need to be clear and simple to use to reduce the chance of mistakes.”

Some local residents questioned the need for city-wide notifications. One called the tsunami threat to Berkeley “totally bogus.” Another called the messaging “Kind of strange,” adding, “the tsunami alert isn’t meant for anyone on land.”

“I’m going to assume that someone made a split second decision to risk overreacting because they weren’t set up to alert ONLY the Marina,” another community member wrote. “But it was startling to wake up to.”

Some of the reporters covering the Tonga tsunami in the Berkeley Marina on Saturday, Jan. 15, 2022. Credit: Scott Stanfield

As of about 10 a.m., the Berkeley Marina was “packed with reporters,” local photographer and resident Staci Prado told Berkeleyside. The roads were still blocked to vehicles, but many people entered the marina on foot to witness the unusual weather firsthand. There were no big waves crashing, but there was a noticeable increase in the seawater flow and unusual patterns in the water.

The American Red Cross also responded to the marina to ensure residents who had to leave their boats were as comfortable as possible.

“The hot coffee was welcome (and finished),” Red Cross volunteer Scott Stanfield told Berkeleyside. “One live-aboard asked if we had dog toys and we did! (A little mickey mouse toy.) I think, if you could ask the residents we served (about 30), they likely appreciated the cell phone charger!”

At 10:20 a.m., Berkeley sent out its second AC Alert to marina residents: “EVACUATION ORDER is still in effect for the Berkeley Marina boats, docks, and shoreline. The Tsunami Advisory is still in effect. See tsunami.gov, and community.zonehaven.com for details.” 

A similar message went out to all of Berkeley via Nixle about 30 minutes later, this time using the word “advisory” rather than “warning.” In subsequent messages, Berkeley did not use the word “warning” again.

The next Berkeley AC Alert came at 3:30 p.m. saying evacuation orders had been lifted but the tsunami advisory remained in effect: “Use caution on boats and docks,” the message said. It again pointed to tsunami.gov and community.zonehaven.com. A Nixle at 4:40 p.m. had the same information.

There followed a lull. At 7:52 p.m., a Berkeley AC Alert announced the end of the tsunami advisory. That message did not go out via Nixle.

Oakland and Richmond police both use the Nixle system but seem to have issued no emergency messages throughout the day Jan. 15. It’s unclear whether Contra Costa County put out any tsunami notifications because only active alerts are visible on its website.

Aside from Albany, no local agency aside from Berkeley appears to have sent out a single tsunami notification after 9 a.m.

Albany put out three messages during the day. As with the other jurisdictions, the initial 7:41 a.m. message described the alert as a “tsunami warning.” Like Berkeley, it also called for the emergency evacuation of its most low-lying section of town, which includes the Albany Bulb park and Golden Gate Fields racetrack. It said the “Tsunami ETA” was 8:10 a.m.

Its next message, a “tsunami advisory” at 11:13 a.m., urged community members to “Avoid the Albany Shoreline.” Its final message of the day advised community members at 7:50 p.m. that the advisory had been lifted.

Berkeley tsunami was ‘a curveball for the system’

After the tsunami surge, most people in Berkeley seemed to return to their regularly-scheduled three-day weekend. For some, come the workweek, the wild weekend weather was a distant memory.

Other parts of the coastal Bay Area and Santa Cruz had seen harbor damage, dramatic flooding and big waves, not to mention ocean rescues. In Berkeley, not so much. Local authorities said there was no noticeable damage in the waterfront.

But that hasn’t stopped the city from taking stock of what worked last weekend and what might be improved.

“It was a curveball for the system,” Assistant Berkeley Fire Chief Keith May told Berkeleyside. “This is a new tsunami plan we just started working on last year. We had enough of it down so we could roll with it.”

Berkeley first responders focused on the marina during the Tonga tsunami event Saturday, Jan. 15, 2022. Credit: Scott Stanfield

May said Berkeley gets its guidance about how to proceed when a tsunami is coming from Cal OES (the California Governor’s Office of Emergency Services). After the 2011 earthquake in Japan, the state created a tsunami playbook that it’s regularly revising. The playbook outlines what actions jurisdictions should take depending on what level of surge is expected.

According to the latest state guidelines, May said, Berkeley was to evacuate people from boats, docks and shorelines.

“That’s what our plan calls for,” May said. “The priority was to get the people off the boats. For that, I think it went very well, even if we were the only ones in Northern California evacuating people off the coastline.”

As of Friday, it wasn’t entirely clear which other places might have proceeded with evacuations. The state is still collecting that data.

But May said he had fielded a number of calls during the tsunami response from local agencies that had questions about what Berkeley was doing — and why. Berkeley was following the state guidance, he told them.

This past Wednesday, several of the individuals who are tasked with pushing city of Berkeley announcements out to the community met for a debrief. This coming week, another session is planned for first responders.

On Wednesday, May said, a few key areas for improvement came up, such as making sure enough city staff are on hand early to come up with a crafted, clear message for the broader community. In response to a Berkeleyside question, May said he wasn’t sure exactly how the word “warning” had gotten into the Nixle mix.

Under the circumstances and on a very tight timeline, he had debriefed BPD verbally about the tsunami threat. Next time, staff would collaborate on a unified, fully vetted message for the city.

“I give the police department a lot of credit,” May said. “It’s hectic, you’re in the heat of the moment. It’s someone who doesn’t necessarily know the tsunami policy. I could see that translation getting kind of lost.”

May said he would have liked to put out messages on Twitter last weekend and to have had a spokesperson at the waterfront earlier in the day. He’s also planning to work on more robust messaging to other local agencies.

The middle-of-the-night timing on a holiday weekend certainly didn’t make things easier. May himself was on vacation in Tahoe when the underwater volcano erupted in Tonga. The initial tsunami alert from the state, which came in on his personal phone, woke him up.

May said he later learned he was the only Berkeley staffer to get the state alert. Last year he had submitted a long list of Berkeley emergency contacts to Cal OES for that purpose, but the state had switched to a platform where only one person per jurisdiction is notified. May said he is pushing to get at least three people from Berkeley on that list.

Learn more about Zonehaven in past Berkeleyside coverage

May said the AC Alert messages to the people most at risk, those in the marina, had worked as planned and that Zonehaven, a Bay Area-wide system, had reported its largest spike of the day in Alameda County. That was true even though the biggest weather impacts took place elsewhere.

May said he saw that as a good sign on the notification front: “People were getting the message,” he said.

Resources to prep for natural disasters in Berkeley


It can be overwhelming to track all the resources related to staying safe if a disaster strikes in Berkeley. Here are some of the key links to help you prepare.

Kate Darby Rauch contributed reporting to this story.

Emilie Raguso (former senior editor, news) joined Berkeleyside in 2012 and covered politics, public safety and development until her departure in 2022. In 2017, Emilie was named Journalist...