Yes, parts of Los Angeles are sinking, and some areas have been doing so for decades. Satellite measurements taken between 2015 and 2023 show that different neighborhoods across the LA basin are dropping at varying rates, with the most affected zones losing up to about 30 millimeters (roughly 1.2 inches) per year. The sinking isn’t uniform. Some spots are barely moving, others are dropping steadily, and a few areas are actually rising due to tectonic compression.
Why Parts of LA Are Sinking
Three main forces pull the ground downward across the Los Angeles basin: groundwater pumping, oil extraction, and natural tectonic movement. Separating these causes has been one of the bigger challenges for scientists studying the region, because the signals overlap and sometimes mimic each other in satellite data.
Groundwater withdrawal is the dominant driver in certain inland areas. In the 40-kilometer-long Santa Ana basin southeast of downtown LA, pumping and re-injecting groundwater produces about 12 millimeters per year of long-term subsidence. That same area experiences a remarkable seasonal bounce, with the ground oscillating up to 55 millimeters vertically as aquifers fill and drain throughout the year.
Oil extraction has historically caused the most dramatic sinking. The Wilmington oil field, beneath the Long Beach and Wilmington neighborhoods, produced subsidence across a 22-square-mile area, with total sinkage ranging from 2 feet to as much as 30 feet before water injection programs were implemented to stabilize the ground. That remains one of the most extreme cases of oil-related subsidence anywhere in the United States.
Beneath all of this, tectonic forces are slowly compressing the basin. A U.S. Geological Survey study that carefully stripped away the effects of groundwater and oil pumping found 4.4 millimeters per year of tectonic contraction across the LA basin, oriented roughly northeast to southwest. This compression is driven by blind thrust faults, the same type of hidden faults responsible for the 1994 Northridge earthquake.
Where the Sinking Is Worst
The highest current subsidence rates cluster around areas with active oil fields and heavy groundwater use. Near the Inglewood oil field in south-central LA, satellite radar measurements have recorded maximum sinking of about 30 millimeters per year. The area around Long Beach and Wilmington, though far more stable than it was during mid-20th century oil production, still shows measurable downward movement.
The picture across the broader basin is patchy. Some neighborhoods sit on bedrock and barely move. Others sit on compressible sediments or above depleted underground reservoirs and sink measurably year after year. The fractions-of-an-inch annual changes may sound trivial, but they accumulate over decades, and they interact with other risks in ways that matter.
How Sinking Compounds Sea Level Rise
This is where subsidence shifts from a geological curiosity to a serious planning problem. Sea level rise projections for coastal cities typically account for ocean warming and ice sheet melt, but they often underestimate what happens when the land itself is also dropping. A 2024 study published in Science Advances found that regional estimates substantially understate sea level rise in parts of San Francisco and Los Angeles, projecting more than double the expected rise by 2050 when local land sinking is properly included.
The compounding effect is straightforward: if the ocean rises half an inch and the land drops half an inch, the water appears to rise a full inch relative to the shore. For parts of Los Angeles and San Diego counties, human-driven land sinking from oil and groundwater extraction could add up to 15 inches (40 centimeters) of uncertainty to sea level projections by 2050. That’s a significant margin when coastal planners are designing flood defenses, drainage systems, and building codes.
Even small elevation changes alter local flood risk, wave exposure during storms, and the extent to which saltwater pushes into freshwater aquifers. Neighborhoods that were safely above flood thresholds a generation ago may not stay that way if the ground beneath them keeps dropping while the ocean keeps climbing.
How LA Compares to Other California Cities
Los Angeles is not the fastest-sinking area in California. That distinction belongs to parts of the Central Valley, where intensive agricultural groundwater pumping has caused the land to drop as much as 8 inches (20 centimeters) per year in some locations.
Among coastal cities, parts of the San Francisco Bay Area are sinking at a steady rate of more than 10 millimeters per year, particularly in San Rafael, Corte Madera, Foster City, and Bay Farm Island. That sinking is driven mainly by compaction of the soft bay sediments that many of those communities were built on. LA’s peak rates in hotspots like the Inglewood field are comparable or higher, but the causes are different, and the geography of risk is more scattered across a much larger metro area.
What Makes LA’s Situation Complicated
Unlike cities that sink primarily for one reason, Los Angeles deals with all the major subsidence drivers simultaneously. Tectonic compression, oil withdrawal, groundwater pumping, and sediment compaction all operate across different parts of the basin on different timelines. Some of these processes are steady and predictable. Others, like groundwater levels, fluctuate with drought cycles, water policy, and seasonal demand, making the ground move in ways that are harder to forecast.
That variability is a core challenge. Traditional sea level projections assumed land movement was roughly constant over time and could be extrapolated from tide gauge records. But satellite data now shows that sinking rates in the LA basin change from year to year depending on how much water and oil are being pulled from underground. A wet decade and a dry decade produce measurably different subsidence patterns, which means projections built on past averages can miss what’s actually coming.
The practical takeaway is that LA is not sinking in a simple, city-wide way. It’s a patchwork: some blocks dropping, some stable, some rising. The risk depends heavily on exactly where you are, what’s underground, and how those local conditions interact with rising seas and changing water management over the coming decades.