Northern California Sinkhole

On the evening of Thursday, April 15, an immense sinkhole opened up in the city of Richmond, California. The hole was approximately 60 feet long, 40 feet wide, and 25 feet deep. The sinkhole swallowed up 2 cars, but thankfully no one was inside the vehicles. Fire officials were on the scene soon after the hole appeared and were planning on hauling the cars out of the hole so they could build a temporary road back over the site, which could allow citizens in the nearby neighborhood to leave their homes.

However, the people living in this neighborhood of about 100 homes do not seem confident that rebuilding the road will fix all their problems. A stream close by the hole was one of the causes of the appearance of the large sinkhole along with a large amount of rainfall this year. As seen in the above diagram and in this presentation, sinkholes are formed by water that seeps down into the soil and dissolves limestone in the aquifer. Over several years, cracks begin to form in the rocky aquifer layer, which make way for small cave openings underground. New construction also causes disruptions in ponds or streams and in turn these waterways put pressure on the aquifer, expanding the large cracks in the aquifer.

With fear of the growing sinkhole, some may be questioning the urban planners of this community. Shouldn't the planners know about the surrounding topography of the land before deciding on building at a certain location? Many planners are familiar with Karst topography and are often faced with the challenge of keeping infrastructures away from these areas, for the simple fact that karst land is prone to creating sinkholes. Therefore, why would city officials insist on continuing the building of a road over this unstable land area, rather than find an alternative route for road building?

Members of the Northern Californian community have previously noticed eroding soil in their yards, but no one has followed up on complaints. This soil loss may be linked to the underground karst region soaking up much of the nearby water. These clues along with topography maps could have prevented this sinkhole formation, but now citizens are trapped inside their neighborhood with no way to drive in or out. Also, local firemen informed citizens that their water use would be restricted during certain hours. Out of the 2 citizens who said their cars were sucked into the hole, only one car has been recovered. Officials have been digging for a while, trying to locate the other car but it still is not even visible.

This ordeal has caused people in the neighborhood much frustration and this is only the beginning of a long line of negative impacts. Recognizing that their is a sinkhole in an area is just the tip of the iceberg. Sinkholes effect ground water and the quality of local streams, wetlands, and other natural environments. Run-off causes chemical changes in these waterways which can also harm species in the area. It is a shame that locals did not prepare building plans for this community with this karst land topography in mind because the negative effects of this sinkhole could have been minimized or even prevented altogether.