Mexico Sinkhole: Authorities Rule Out Water Pumping as Cause, Calls It 'A Natural Process'

A huge sinkhole suddenly appeared on a farm in Puebla, Central Mexico, back in May, and residents are blaming industrial water pumping through the ground - and a new study by experts say otherwise.

A new report from the Mexico National Water Commission pointed out that the erosion of the limestone bedrock underneath the farmland was the cause of the sinkhole and not excessive water pumping. The industrial activity had been attributed by residents to factories, particularly a water bottling plant in the area that was previously closed because of the believed risks in the area's water table.

"There is no evidence that the cause of the sinkhole was water extraction," the Commission said in a statement Sunday, July 4, as reported by AFP. Additionally, they described the cause of the Mexico sinkhole as "a natural process of limestone being dissolved."

A Large and Growing Mexico Sinkhole

The Mexico sinkhole, which grew to a width of almost 200 feet (60 meters) and a depth of almost 66 feet (20 meters), first appeared in farmland in Santa Maria Zacatepec in Puebla state. In a previous report from local news outlet El Sol de Mexico, environmental secretary Beatriz Manrique discloses that the gaping hole started at only 15 feet wide and rapidly grew over time. The initial theory was that the farmland softened because of the presence of a "jagüey," which refers to a ditch or well full of water. As the water was extracted continuously, the farmland bedrock softened and gave way because of erosion, creating a massive void. Meanwhile, residents believe that a water pumping operation might have contributed to the sinkhole opening,

As the hole initially opened back in May, it also prompted the state's Civil Protection department to inspect the area in coordination with the relevant agencies to evacuate those in the immediate vicinity and to erect a 500-meter security fence around the Mexico sinkhole.

A few weeks later, the Mexico sinkhole again made headlines as it continued to grow, starting to swallow a house and trapping a pair of dogs. Now believed to be as deep as 50 feet at the time, its bottom is filled with fast-running currents, forcing the authorities to take additional precautions.

But, How do Sinkholes Actually Form?

According to the US Geological Survey, sinkholes commonly form where the layer underneath the surface is made up of limestone, carbonate rock, salt beds, or any other bedrock substances that can be naturally dissolved by running groundwater. As the rocks beneath are subjected to erosion, as the case in the Mexico sinkhole, gaps and voids develop. There are usually no warnings as the surface stays intact until the underground cavern grows to a level where it can no longer support the structure above and collapses.

While sinkholes are mostly created by natural processes, the US government agency warns that there are sinkholes that are caused by anthropogenic activities. Modern land-use practices, most particularly groundwater pumping as well as construction and land development. Additionally, sinkholes could be induced by changing natural water-drainage patterns or when land surfaces are altered.

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