California is hit with numerous sinkholes following heavy rains and flooding.

Sinkholes to Swallow a Portion of California

California has been struck by numerous "atmospheric river" events since late December. Heavy rainfall and snow cause widespread destruction, including 18 casualties.

The wet conditions also led to the formation of a number of sinkholes in the states. Sinkholes are expected to swallow a chunk of the state, Newsweek reported.

The state is expected to endure more wet weather in the coming days, so more sinkholes could possibly open up. The outlet noted that sinkholes form very slowly, so they are barely noticeable. However, the collapse of the ground can happen quickly and unexpectedly.

Sinkholes in the Chatsworth Swallows 2 Cars

One large sinkhole was reported in the middle of a street in the Chatsworth neighborhood of Los Angeles during a day of non-stop rain and it swallowed two cars. Firefighters had to rescue them, KTLA 5 reported.

The Los Angeles Fire Department reportedly received calls about a sinkhole located at 11414 Iverson Road, near the 118 Freeway, around 7:20 p.m. Monday. A mother and daughter were rescued and taken to the hospital after their vehicle plunged into the sinkhole.

Four people were initially trapped, but the other two were able to exit their vehicle uninjured before the first responders arrived, according to a news release.

The road had continued to "sluff and deteriorate," so the crews had to secure the cars from further shifting to rescue the occupants. The firefighters conducted a high-angle rope rescue operation and used the aerial ladder to safely extricate the mother and daughter. They sustained minor injuries and were taken to the local hospital.

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What is a Sinkhole

A sinkhole is a depression in the ground without natural external surface drainage. It occurs when it rains, and the water stays inside the sinkhole and typically drains into the subsurface, according to USGS.

Sinkholes are common in areas geologists call "karst terrain" - these are regions where the types of rock below the surface naturally dissolve by groundwater circulating through them. Soluble rocks include salt beds and domes, gypsum, limestone and other carbonate rock.

Florida sits in an area largely underlain by limestone, so it is susceptible to sinkholes. When it rains, the water moves down through the soil and the rocks begin to dissolve, creating spaces and caverns underground. Heavy rain and flooding increase the likelihood of sinkhole formation.

Sinkholes are dramatic because the land surface usually stays intact for a period of time, but the underground spaces could get too big. When there is not enough support for the land above the space, it suddenly collapses and forms a sinkhole.

A sinkhole is different from a pothole because it is a closed natural depression in the ground surface due to the removal of material below the ground and results in either collapse or gradual subsidence of the land surface. A pothole, on the other hand, is a small feature due to the failure of paving materials associated with roads, parking lots and airports. They are abundant in the colder part of the country.

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