Drought-Stricken California Lake Set to Overspill After Heavy Rain

A California lake is set to overspill for the first time in over two decades due to the great mount of rain descending on California.

Lopez Lake, in San Luis Obispo County, 10 miles east of Arroyo Grande, was at 22 percent of its full capacity at the beginning of December 2022. It was very close to being at the lowest level ever recorded.

But currently, it is at over 90 percent its capacity, and experts expect it to overspill any day now. This would be the first time the lake has spilled in 25 years, KEYT reported.

The lake is measuring the highest water level seen since 2012, according to the news outlet.

Brian Wilder, Lopez Lake supervising park ranger told KEYT: "We're about 5 feet from the spillway, which means water will start going over the spillway and that's at about 522 feet, so we're about 5 feet below that. Came up about 25 percent in the last week, which is really impressive for Lopez. It's typically pretty slow filling."

The creeks and waterways are all flowing fast and heavy, Wilder said. The usually slow-moving lake is flowing at a rate of a tenth of a percent every two hours, "which is fast for here," he said.

California saw a historic amount of rainfall between December 26 and January 19. The wet weather continued throughout the winter period. At the end of February, the state was hit by strong snowstorms, even in areas used to bone-dry conditions like Los Angeles.

The state is expecting even more rain next week, which will likely cause Lake Lopez to spill.

Lopez Lake was not the only reservoir seeing extremely low water levels in California.

The state has been in the grips of a drought for two decades. Experts have largely put this down to climate change. The recent influx of rain and snow has greatly improved the state's drought status. Before the rain, the state's reservoirs were in a dire state. But many are now newly replenished.

A drought-monitor map from October 2022 showed large portions of California to be in an extreme or exceptional drought. The rest of the state was in a severe drought, with small portions in a moderate drought or abnormally dry.

A map from February 28, after heavy rain and snow swept across the state, showed vastly different conditions. Most of the state is now classed as abnormally dry. Some small portions are in a moderate-to-severe drought.

But there is still a way to go before California is completely out of the drought.

Hydrologist Roger Bales, a distinguished professor of engineering at the University of California Merced, previously told Newsweek: "It is good to remind folks that asking if the drought is over may be the wrong question. We welcome average or above precipitation years, with the caveat that big storms, especially warm atmospheric rivers, increase flooding hazards. Also, think of California's precipitation as being a series of dry to average years punctuated by a smaller number of wet years. Then subtract a constant value from each annual precipitation amount, to get a much more variable runoff amount."

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