When the Big One hits California – and seismologists say it’s not if, but when – there might not be blaring sirens or vibrating phones giving people a precious few seconds to prepare.

At least, those warnings won’t come if a quake hits in the foreseeable future. California’s earthquake warning system, long discussed and partially built, remains incomplete and in limbo. And if the Trump administration has its way, it might be unfunded too.

But the powerful earthquakes that hit Mexico last month serve as a reminder of what’s possible. There, sirens blared between 20 seconds and 60 seconds before the shaking began. Because of that, experts say, the quakes that killed hundreds also provided the latest real-world example of how a warning system can save countless more.

“If you look at the videos of people rushing out of the buildings before the earthquakes, there were lots,” said Peggy Hellweg, the operations manager of the Berkeley Seismological Laboratory, which studies quakes and quake warning systems.

“There were at least thousands of people who were saved.”

Related Articles New earthquake, magnitude 6.1, shakes jittery Mexico

Trying to contact family or friends affected by the Mexico earthquake? Here’s where to start But experts say the difference between what happened in Mexico and what’s also happened in Japan in a similar fashion — and what isn’t yet possible in California — is stark.

“We’re behind the curve,” said Doug Given, who works as the earthquake early warning coordinator for the U.S. Geological Survey, which is spearheading a stalled effort to create a system that would touch California, Oregon and Washington.

Given pointed out that Mexico, Japan, Italy and China built functional quake warning systems after suffering huge quake-related losses.

This Sept. 13, 2011 photo shows Anthony Guarino Jr., a seismic analyst at the California Institute of Technology, demonstrating an early earthquake warning system in Pasadena, Calif. (SCNG file photo)

A woman speaks on her cell phone as people evacuated from office building gather in Reforma Avenue after an earthquake in Mexico City, Tuesday Sept. 19, 2017. An earthquake early warning system is credited with saving lives. (AP Photo/Rebecca Blackwell)

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In this photo taken Thursday, Aug. 6, 2015, earthquake monitors that will be placed on the Oregon and Washington coasts sit on a table at the Pacific Northwest Seismic Network at the University of Washington, where they are prepared for installation, in Seattle. When North Americas undersea edge and a tectonic plate pushing beneath it inevitably give way to three centuries of accumulated stress, unleashing a monster earthquake and tsunami in the Pacific Northwest, the expected catastrophic loss of life and economic disruptions could be lessened by an early warning system tied-in to the monitors. (AP Photo/Elaine Thompson)

People react on a street in downtown Mexico City during an earthquake on September 7, 2017. An earthquake of magnitude 8.0 struck southern Mexico late Thursday and was felt as far away as Mexico City, the US Geological Survey said, issuing a tsunami warning. It hit offshore 120 kilometers (75 miles) southwest of the town of Tres Picos in the state of Chiapas. (PEDRO PARDO/AFP/Getty Images)



“Many countries have had huge disastrous earthquakes that created the political will to take action,” Given said.

He’s hoping the same cycle won’t happen here.

The latest estimate on the cost of an earthquake warning system in the western United States is about $38 million to complete the one-time start-up costs and another $16.1 million a year to operate it.

Those numbers — which quake experts and economists say are tiny when compared with the human and financial losses associated with quake-related health spending and other preventable costs — are too steep for the federal government. An early draft of the federal budget eliminated the region’s early warning system entirely, though a subcommittee in the House of Representatives later restored $10.2 million to the program.

That still won’t be enough to finance a network of 1675 sensors needed to have a system for the western United States. So far only 740 sensors are operational, and many are concentrated across Southern California.

“We really can’t build the complete system with two-thirds of the funding,” Given said. “It would be imprudent to build a system you can’t maintain.”

The shortfall is prompting agencies to consider seeking private funding, perhaps from utility companies and others that might be vulnerable to quake costs, said Tina Curry, deputy director of planning, preparedness and prevention for the California Office of Emergency Services.

“We’re rapidly trying to get that infrastructure in the ground,” Curry said. “From that, everything else will come.”

But Curry isn’t ruling out a change of heart in Washington, either.

“We’re hopeful that the federal government will continue to partner as they have.”

The warning system contemplated in the United States relies on a series of underground sensors that would detect quakes as they happen and spread that information to sensors throughout the potential quake zone faster than the shaking itself. Specifically, the detectors would track the less damaging p-waves (or primary waves) that are emitted in a quake’s initial moments, and use that information to tell more distant sensors that the more damaging quake waves (s-waves, or secondary waves) are heading their way.

The system isn’t perfect. Areas close to the epicenter of a quake are so-called blind zones, meaning they get little or no warning before the shaking starts. But areas that are distant to the center of a quake — and quakes can reach hundreds of miles — get some warning, typically between 20 and 60 seconds.

If the warning sounds brief, experts point out there are plenty of ways the warning can save lives, money and inconvenience.

A warning of even 20 seconds is long for a family to get out of a house or apartment, or for a business to evacuate an office. It’s enough time for a doctor to put down a scalpel or a dentist to turn off a drill. In 20 seconds, an elevator can stop and unload passengers.

Transportation experts note a 20-second warning can be enough time for an engineer to stop or at least slow down a train, reducing the odds of derailment. In some cases, vulnerable bridges could be closed to traffic.

A 2016 paper in the journal Seismological Research Letters examined the benefits and cost of an early earthquake warning system found that if people had advanced notice of a temblor, injuries could be reduced by 50 percent.

Even a small increase in the number of lives saved and fires prevented would pay for one year of operating a quake warning system. Saving three lives alone would pay for the cost of operating a West Coast early warning system for a year, as would one train derailment prevented, the paper found.

It’s not a theoretical problem. There is a 99.7 percent chance of a magnitude 6.7 or larger earthquake striking California in the next 30 years, according to a 2014 U.S.G.S. study. In the Pacific Northwest there is a 10 percent chance of a “megathrust” earthquake with a magnitude 8 or 9 along the 700-mile long Cascadia subduction zone that runs from Vancouver Island to central Oregon.

Those quakes — with or without a warning system — probably will cause billions of dollars worth of damage.

The planned system for Washington, Oregon and California would install sensors every six miles in high-density areas with powerful fault lines capable of serious damage. Further afield sensors would be spread out every 12 miles, and in places where damage would be minimal, every 24 miles.

“We have a number of goals, one is to produce the fastest possible alert in populated areas,” Given said. “We’re prioritizing the highest risk targets.”

A pilot system is already up and running with dozens of schools, transit systems, utility companies and cities receiving notices of impending earthquakes, including the cities of Los Angeles and San Francisco, and companies like Boeing and Intel. That system has found technical glitches that must be fixed before a broader rollout, but those glitches are surmountable.

People working on the mass notification system don’t want to see the mass casualties that spurred other governments into action.

“I hope the next big one will wait,” Hellweg said.