Can a sandbag burrito protect two Bay Area counties from floods?

Jan 4, 2017

This week promises lots of rain for the Bay Area — but too much of a good thing can sometimes turn bad. Erosion, mudslides and flooding are a danger.

In 1998, El Nino storms caused over half a billion dollars of damage statewide. 17 people died, and 35 counties were declared federal disaster areas. East Palo Alto was hit especially hard. The San Francisquito Creek flooded after a week of heavy rain and damaged 1700 homes. This winter, residents are worried the same thing could happen again.

 

A lot of rain in 1998

Spencenia Sims remembers the 1998 flood like it was yesterday.

“It wasn’t as cold as it was this winter, but it was a lot of rain,” she says.

Her backyard borders the San Francisquito Creek in East Palo Alto. She and her husband Curtis have lived in their home here for 50 years.

18 years ago, Curtis was watching television when he got a call from his neighbor, asking if they were going to evacuate. He was surprised – he and his wife hadn’t noticed anything was wrong.

“I went over and [the water] was coming through the patio door, and it was up to the patio,” Curtis says. “So that’s when we left.”

As they scrambled to leave, firemen and police officers began driving around in cars and boats, speaking through megaphones, urging people to evacuate.

“It just went all through the house,” Spencenia adds.

She and her husband were out of their house for three months. They moved in with a relative a few blocks away. They didn’t have flood insurance, so they had to pay most of the repair bills themselves -- thousands of dollars -- before they could move back home. Then, in 2012, the creek overflowed again. This time, it only flooded their garage. But it was pretty bad outside.

“We had water up to almost our knees when we got in the car to leave here,” Curtis says.

A backyard hazard

Curtis takes me out into the backyard to show me signs of the previous floods.

He points to a fence they built after the 1998 flood. The creek is right on the other side. Curtis unlocks the gate and we walk out onto the creek’s levee. It’s basically just a raised pile of gravel and dirt. The bottom foot of the fence is coated with a fine layer of dry mud. He says it’s left over from 2012.

 

“Most of the water spread across this whole area,” he says.

Curtis hopes that if the creek overflows this year, it’ll be different. That his neighborhood will be protected by something called a “sandbag burrito.” Yes, a sandbag burrito.

Sandbag burrito

“Basically it’s taking sand either in sandbags or free sand and wrapping it in concrete,” says Len Materman, the executive director of the San Francisquito Creek Joint Powers Authority.

The sandbag burrito in the process of being built.
Credit Angela Johnston

 

Sandbag burritos are actually a well-known piece of infrastructure in the engineering world. On the outside, they don’t look much like actual burritos, just long cement mounds. It’s the wrapping process that gives them their name. The sand is like the rice and beans. That gets wrapped tightly in a tarp - the tortilla. And then that gets wrapped again in cement - the foil. Their purpose is to raise the elevation of the levee to match what’s on the Palo Alto side, and keep the water from overflowing.

The San Francisquito creek runs through the towns of Palo Alto, East Palo Alto, and Menlo Park. It also divides two counties -- Santa Clara County and San Mateo County.

After the 1998 flood, the cities and counties that the creek runs through got together to try to restore it, to make sure the same thing didn’t happen again. The idea, Materman says, was to transform the creek into something that people could be proud of, not afraid of.  But that’s easier said than done.

“It’s very difficult to work on a creek that’s a county a line and a city line, because you have different players that have different interests, and there's no way to fix half of it,” Materman says.

The sandbag burritos were constructed early last year in preparation for El Niño. They’re only temporary, though - they’ll last about 4 or 5 years before they start to rot and disintegrate from within. The real fix has just started - completely rebuilding the levee. Making it wider, higher and stronger - to prevent flooding in even the worst of storms.

 

“This whole community here is below sea level and if water overtops, it basically just starts filling up behind the levee,” Materman explains. “It doesn’t have a way to drain to the Bay, and that’s a really dangerous situation when you have homes that are so low and adjacent to a levee. It’s kind of like a bathtub, it starts filling up, and that’s what really worries us.”

You can look down on homes when you are standing on the San Francisquito creek's levee.
Credit Angela Johnston

It’s especially worrisome because one side of the creek is more vulnerable than the other. Materman and I are standing on the bank of the creek in East Palo Alto, and just feet away, directly in front of us, is the city of Palo Alto. It’s a completely different city, with a different government, a university, an airport, and the 101 freeway. Palo Alto is not below sea level. It’s also one of the wealthiest cities in the Bay Area. East Palo Alto is one of the poorest. And most of the 5000 or so homes in the creek’s floodplain are in East Palo Alto.

“I mean there’s definitely property damage and life safety issues in Palo Alto,” says Materman. “But in terms of life safety, this is the really critical area right here [in East Palo Alto].”

Flooding isn’t fair

If the Palo Alto side of the creek is built even just an inch higher, East Palo Alto will always flood. That’s why it was important to build the sandbag burritos the exact same height on both sides.

“Absolutely equal protection,” Materman says. “That’s what we strive for.”

Last year’s El Niño was predicted to be stronger than the one in 1998 -- the one that displaced Spencenia and Curtis Sims, and so many others from their homes. But it didn’t live up to the hype.

“This will protect people from what we saw three years ago, but not what we saw [18] years ago,” he says.

Only a new, rebuilt levee will prevent that type of flooding. The permanent fix was supposed to be finished last year, but because of the mix of cities, counties, and organizations involved, construction only started this past June.

“If we had gotten our permits 12 months after we applied, the two year construction project would’ve been built by the time this winter comes around, and that’s really just an unfortunate situation,” Materman says.

But at least both sides of the creek are talking, he says.

Preparing for the worst, hoping for the best

Dennis Parker lives just down the street from the Sims in East Palo Alto. He moved here in 1999, the year after the last big flood. He knows that the sandbag burritos won’t work as well as the permanent fix. But he thinks they are a good start. His house doesn’t back up along the creek, but he’s still preparing his family and his neighborhood for a major flood.

Parker became a leader of his community emergency response team. He learned how to operate a ham radio, and keeps emergency kits in his two cars and garage.

Even though he’s getting ready for the worst, it’s been difficult to convince his neighbors to do the same.

“People are just apathetic in general,” Parker says. “Some of it’s apathy and some of it’s denial. ‘It’s not really going to rain that hard.’ They look up at the sky and say ‘Ah, it doesn’t look like it’s going to be that much rain.’ So people would rather not face that kind of thing.”

At an El Niño preparation meeting last year, only a dozen or so residents came out. This upsets Parker. He says it might be because of a language or cultural barrier. According to the last census, East Palo Alto is over 60 percent Latino. Whatever the cause, it makes him worried about how people are going to know something is wrong

“Sometimes I kind of wonder whether the warning might be trash cans falling over, and the back fence falling over,” he says. “How do you really know when it’s time to get out of here?”

A new flood warning app created by Len Materman and the Joint Powers Authority can help, but you need Internet or cell phone access to use it. I asked Spencenia and Curtis Sims if they’ve signed up. They don’t use the Internet, they told me. They’ll get live updates from friends and family.

“You ain’t got to worry about it, somebody’s going to always be checking on that creek, so we'll be aware...we’ll know it when it happens," Curtis Sims says.

The Joint Powers Authority has paused construction of the levy for the winter. They hope to resume in the spring. Until then, people like the Sims are relying on their neighbors...and the sandbag burritos.
 

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