The ghost lake rising in California (2024)

• A series of heavy storms over California has helped fill many of the state's reservoirs and led to the re-emergence of Tulare Lake.
• Tulare Lake used to be the largest freshwater lake in the Western U.S. but dried up 80 years ago.
• One expert has called the re-emergence of the lake an "unfolding natural disaster" because there is no way to handle it with existing infrastructure.

California has just seen one of the wettest periods in recent memory. The rain battering the state has filled many of the state's drought-stricken reservoirs, and some are overflowing for the first time in a decade.

And Tulare Lake, in the San Joaquin Valley, is even appearing as if from nowhere. But the lake has actually been there for years.

What Happened to Tulare Lake?

Tulare Lake used to be the largest freshwater lake in the Western U.S., fed by water flowing down from the Sierra Nevada. It dried up about 80 years ago when the land was re-developed for agricultural purposes.

When this happened, rivers were diverted elsewhere and it became farmland. So Tulare Lake was no more, and it has mostly been sitting dry ever since.

"Pre-development, Tulare Lake was once the second-largest freshwater lake west of the Mississippi. Being landlocked, without a natural watercourse to the sea, the water filled groundwater stores and otherwise evaporated in a natural cycle that likely provided moisture back to its source—the southern Sierra Nevada," Keith Musselman, an assistant professor at the Institute of Arctic and Alpine Research at the University of Colorado, Boulder, told Newsweek.

"The lake was a vast wetland that supported prolific wildlife and large Native American populations. Geological evidence suggests that it was a remnant of an even larger ancient lake that covered much of California's Central Valley and that alternatively drained and filled as earthquakes and erosion shaped the California landscape and river systems," he said.

Now, it is aptly nicknamed the "ghost lake" by local people, as it occasionally reappears when the state experiences a particularly wet season.

Following a series of atmospheric rivers that fell on the state throughout much of winter and early spring, 2023 has been such a year.

Tulare Lake is now rapidly re-emerging.

How Has Tulare Lake Reappeared?

The snowpack in the Sierra Nevada mountains has reached record-breaking levels in recent months due to the storms.

Following the storms in March, data from the California Department of Water Resources recorded that the snowpack was 257 percent greater than the average for this time of year, and 247 percent larger than is average for the usual snowpack peak on April 1.

Now spring has arrived, the snowpack is beginning to melt. And while the state desperately needs water, as the drought has lasted so long, this is posing challenges.

The lake used to fill the lower area of the Tulare Basin—which is located to the south of California's San Joaquin Valley. The basin is shaped like a huge bowl.

"The story with the flooding in Tulare Lake is that it is a closed basin with no natural outlet," Nicholas Pinter, professor of applied geosciences and associate director of the Center for Watershed Sciences at the University of California Davis, told Newsweek.

"Since draining the lake in the early 1900s, it has been seasonally flooded again in 1938, 1955, 1983, 1997, and 2017. Given the current Sierra snowpack, flooding of the lake is likely to rival and possibly exceed 1983, when 130 square miles of former lake bed were refilled and took 2 years to drain," he said.

The main problem is that the water currently flooding Tulare Lake is only a small fraction of this record snowpack.

This snowpack could continue to melt, and feed into the already overflooded lake, well into the summer. It remains to be seen just how much of a problem this will pose.

"Between October and April, many regions saw more than double the average precipitation that falls in most years during that same period," Musselman said. "This is both a welcome change from the nearly decade-long drought conditions suffered by the State and a challenge to deal with the resulting flood waters."

The Problem With Tulare Lake

California has been in a drought for over a decade. Unusually dry conditions paired with overuse of water has meant that water sources are being used more quickly than they can be replenished. It is easy to think that the refilling of this lake would be a good thing, seeing as the state is in desperate need of water.

However it is actually wreaking havoc on local communities. It is not unusual for areas that have endured severe drought to then suffer severe flooding. When the ground becomes so parched during a long, dry period, incoming water can then fail to saturate in the ground. This results in flash flooding.

Jeffrey Mount, a senior fellow at the Water Policy Center of the Public Policy Institute of California, told NBC that there could be more than 100,000 acres of land underwater this year due to the refilling of Tulare Lake.

Experts have predicted that the lake could remain in the area for much longer than it has previously, and this will massively disrupt crop growth. California's Central Valley is a hugely important agricultural area, producing one-quarter of the nation's food, according to the U.S. Geological Survey, which says more than 250 different crops are grown there with an estimated value of $17 billion a year.

Many farmers live very close to Tulare Lake. As the flooding began, they began working quickly to block overflowing banks.

The largest city close to the lake is Corcoran, which has a population of 22,000. Many homes here have flooded and many roads closed, NASA reported.

There are also smaller towns in the lake's vicinity. Allensworth and Alpaugh have suffered from floods caused by overflowing rivers. Many areas were under evacuation warnings.

Mount told NBC that the re-emergence of the lake is an "unfolding natural disaster." This is simply because there is no current way to handle it with the existing infrastructure, he told the news outlet.

The situation with Tulare Lake foreshadows many challenges to come for the rest of the state as long, dry periods are followed by extreme wet periods.

"A recent article [from CalMatters] nicely described this as California's precipitation paradox: The State has both too much water and not enough," Musselman said. "On the one hand, the State has more water than it can handle with more on the way as near-record snowpack in the Sierra Nevada begins to melt. On the other hand, there isn't enough water to satisfy the State's long-term needs, and memories of drought stress and wildfire risk are still fresh."

Experts believe that the "whiplash" weather in California, and other drought-stricken states, will only continue.

Flooding remains a serious issue for many farmlands in California's Central Valley.

"Ongoing efforts to allow flood waters to temporarily flow over agricultural land in California are aimed at refilling critical groundwater coffers that are key to resilience during periods of drought. Replenishing groundwater can reduce the effects of subsidence of the valley floor that happens when pumping causes groundwater levels drop and soils to compact," Musselman said.

"The flooding we are witnessing is a natural process that can benefit water supply and ecosystems, yet development and draining of flood plains continues to put property and lives at risk. Flooding of agricultural land, or on-farm groundwater recharge, is one way to divert floodwaters from communities and benefit long-term water supply."

While it is important to mitigate the effects of climate change as much as possible, adaptation for farmlands and other areas that flood is also the key moving forward.

Pinter said that every flood disaster is a "past error in planning."

"Residents and landowners on the bed of Tulare Lake need to remember that the area refills during wet California winters," he said.

Musselman said that climate change will also continue to "increase precipitation extremes."

"The intensity of both storms and droughts is projected to increase over the coming decades in response to continued greenhouse gas emissions. The precipitation paradox will amplify," he said.

"We must continue to adapt to the precipitation paradox. This will include preparing for and mitigating floodwaters in years of plenty and conserving and storing water above and below ground to be resilient to years of drought. Advocacy to enact policy change is perhaps the most effective long-term solution to protect life and property for future generations of Americans."

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