C’mon, really? Within California’s gargantuan bureaucracy there is a group of experts that more or less counts the grains of sand on state beaches?
Pretty much. The scientists and agency officials work from a statewide ‘sand budget’ that determines the volume of sand that should reside on the beach. These are not people with rakes, bagging the red cups from last night’s party. Or the guys in small tractors smoothing the beach in front of luxury hotels.
No, this is the California Coastal Sediment Management Working Group.
It figures that in a state where famed beaches are manicured and sand curated, there would be attention paid to movement and disposition of sand itself.
Talk about the Nanny State.
Tracking sand from the Oregon border to south San Diego is serious business. There’s too much sediment in some places, clogging harbors and waterways, and too little in others, shrinking beaches and exposing homes and critical infrastructure.
It’s connected to the problem of sea-level rise, which giveth and taketh away. Warmer oceans can spawn more violent storms, and rising seas can create monumental waves. Bigger waves do demolish beaches and bluffs, but they also deposit sand that replenishes beaches. This dual effect also applies to the physical barriers that we erect to hold back rising waters and pounding waves, redirecting sand where it shouldn’t be or where it’s doing harm. Sand piles up on either side of seawalls and jetties, and the dredging of channels means that sand is dumped somewhere else.
This being California, scientific studies have been ordered. Gary Griggs, a professor of earth science at the University of California, Santa Cruz, isn’t exactly known as Mr. Sand Man. But he could be.
In 2007, Griggs co-authored the first-ever study that examined how human activities have disrupted sediment in and around California beaches. Turns out that our sand is compartmentalized in, yes, big sandboxes called ‘littoral cells,’ which usually contain the sand to local areas. (The literal meaning of littoral here: of or pertaining to the shoreline.)
Sand is a big deal, so much so that the state this June reached a settlement to close down California’s last coastal sand mining operation, which had been scooping up and selling beach sand in Monterey County since the turn of the century. Monterey Bay has one of the highest erosion rates in the state.
It should come as no surprise that there’s a lack of uniformity as to how Californian sand blankets its beaches. In some places sand makes its way to the beach after being sloughed off mountains and into rivers and streams, eventually ending up, as is the way in California, at the beach.
In other places the sand comes in from the sea, scoured off the ocean floor and dumped—along with plastic debris, cigarette butts, and untold numbers of flip-flops—unceremoniously on the shore.
The Santa Barbara cell, for example, has a lot of sand in it because four rivers drain to the sea. On the other hand, Malibu’s Broad Beach — which really isn’t broad anymore — is sand starved, because sediment from the ocean is being blocked (to save the beach) and the small runoff from the Santa Monica Mountains isn’t making it to the coast.
Griggs knows how things end up. In the case of sand, the sediment moves in littoral drift waves, mostly moving from north to south. He said that people used to think that sand starts up at the Oregon border and ends up in Mexico. It doesn’t.
Sand is intercepted along the way. Human engineering is creating a greater calamity as seas rise and beaches disappear. Protective engineering, such as lathering coastal bluffs with cement, cuts off the shore’s supply of sediment. Throwing up walls in the shallow water stops sand from coming in.
More than 60 percent of watersheds in Southern California have catchment areas at their tail to receive water and sediment, an important flood-control measure. But what happens to that sediment, whose beachward migration is waylaid by huge concrete pits? Tons and tons are scraped out of debris basins and hauled by trucks into the mountains, where the rocks and gravel are reunited with their home ground.
Then when it rains, they roll back down again. And Sisyphus weeps.
- Part 1: California submerging
- Part 2: Shoring up the state
- Shifting sands
- Interactive threat map via Climate Central
To explore more on your own:
- The 2017 sea-level science report to the California Ocean Protection Council
- The 2017 report by the U.S. Geological Survey on Southern California beaches
- The 2015 climate change report of the state Senate Committee on Environmental Quality
- The 2014 legislative report of the Assembly Select Committee on Sea Level Rise and the California Economy
- The 2012 report to the California Energy Commission on San Francisco Bay impacts