The earthquake and tsunami in Japan was felt thousands of miles away in South Florida’s water table.
About 34 minutes after the magnitude 9.0 quake shook the island on March 11, water levels from Orlando to the Florida Keys rose and fell up to three inches, according to the South Florida Water Management District. The reverberations were felt for two hours.
“It shows that the flow in the aquifer is pretty fast, which is good and bad,” said University of Miami earthquake researcher Shimon Wdowinski. “It’s good because we can filter a lot of water through there. But it’s bad because in the case of pollution, it can travel very quickly.”
Florida’s porous limestone allows water to flow easily below the surface of the earth, Wdowinski said. That’s probably why the water table registered changes here.
“The water can flow fast and respond better to the pressure changes induced by a wave,” he said.
The water management district uses deep and shallow wells to monitor the quality of ground water in the Floridian and Biscayne aquifers, which provide much of the drinking water for the area. Oscillations were measured hundreds feet below the surface, said South Florida district spokesman Randy Smith.
Changes in the water table were also measured after the Haiti and Chile earthquakes last year. A 20-foot spike was recorded in South Florida in 1964 after a massive 9.2 earthquake in Alaska, Wdowinski said.
“I wouldn’t say it’s normal, but it’s not unusual” to notice changes, Wdowinski said.
Still, officials were surprised to notice the water waxing and waning after a geological event thousands of miles away.
“This was over 7,000 miles,” Smith said. “I think that proves how strong the earthquake was.”
