LOS ANGELES, Calif. (KSEE/KGPE) – Climate change could create catastrophic flooding in multiple areas of California, including the Central Valley, a UCLA research study warns.

Climate scientists investigating this possibility were motivated by a megaflood occurred in California in 1862, calling it the “ArkStorm scenario,” reflecting the potential for an event of biblical proportions. The new research suggests that, by the end of the century, storms will generate 200% to 400% more water flow in the Sierra Nevada mountains due to increased precipitation in the form of rain and not snow.

In this study, researchers used high-resolution weather models where two extreme scenarios were compared: one that will happen once every century and the other between the years 2081 and 2100. Both will have long series of storms as a result of atmospheric rivers in one month.

The numbers showed that some locations could get over 100 inches of water in one month plus the snow accumulations in higher elevations. In the case of the Central Valley, this could have a major impact on areas affected by recent wildfires.

In the paper, climate scientist Xingying Huang says found that climate change has doubled the chances of getting these extreme flooding events.

“The department will use this report to identify the risks, seek resources, support the Central Valley Flood Protection Plan, and help educate all Californians so we can understand the risk of flooding in our communities and be prepared.”

Karla Nemeth, director of the Califiornia Department of Water Resources

Even though the state has struggled with flooding over the years, nothing has been as devastating as the flood in 1862 when records show the water stretched up to 300 miles long – and as wide as 60 miles across the Central Valley. The state’s population then was around 500,000; now it is close to 40 million. Such a devastating flood could affect cities such as Fresno, Sacramento, Stockton and Los Angeles.

Experts warn that Fresno would be underwater in this scenario, even with the help of the water collection systems such as reservoirs, sleeves, and bypasses.

“Every major population center in California would get hit at once — probably parts of Nevada and other adjacent states, too,” said UCLA climate scientist Daniel Swain.

The study also warned that the damage caused by these high amounts of water to the infrastructure can make almost impossible the response from rescue teams, suggesting closures on major highways such as the I-5 and I-80 for weeks or even months following the flooding.

The report says that one of the next steps is preparing the vulnerable communities and simulating flood evacuations supported by the California Department of Water Resources and the emergency agencies.