Clarksville, TN Online: News, Opinion, Arts & Entertainment.


Topic: groundwater

NASA Study reveals California’s San Joaquin Valley continues to Sink

 

Written by Alan Buis
NASA’s Jet Propulsion Laboratory

NASA - National Aeronautics and Space AdministrationPasadena, CA – Since the 1920s, excessive pumping of groundwater at thousands of wells in California’s San Joaquin Valley has caused land in sections of the valley to subside, or sink, by as much as 28 feet (8.5 meters). This subsidence is exacerbated during droughts, when farmers rely heavily on groundwater to sustain one of the most productive agricultural regions in the nation.

Long-term subsidence is a serious and challenging concern for California’s water managers, putting state and federal aqueducts, levees, bridges and roads at risk of damage. Already, land subsidence has damaged thousands of public and private groundwater wells throughout the San Joaquin Valley.

Total subsidence in California's San Joaquin Valley between May 7, 2015 and Sept. 10, 2016, as measured by ESA's Sentinel-1A and processed at JPL. Two large subsidence bowls are evident, centered on Corcoran and southeast of El Nido, with a small, new feature between them, near Tranquility. (European Space Agency/NASA-JPL/Caltech/Google Earth)

Total subsidence in California’s San Joaquin Valley between May 7, 2015 and Sept. 10, 2016, as measured by ESA’s Sentinel-1A and processed at JPL. Two large subsidence bowls are evident, centered on Corcoran and southeast of El Nido, with a small, new feature between them, near Tranquility. (European Space Agency/NASA-JPL/Caltech/Google Earth)

«Read the rest of this article»

Sections: Technology | No Comments
 

NASA reports Valley Land in California sinking due to Drought

 

Written by Alan Buis
NASA’s Jet Propulsion Laboratory

NASA - National Aeronautics and Space AdministrationPasadena, CA – As Californians continue pumping groundwater in response to the historic drought, the California Department of Water Resources today released a new NASA report showing land in the San Joaquin Valley is sinking faster than ever before, nearly 2 inches (5 centimeters) per month in some locations.

“Because of increased pumping, groundwater levels are reaching record lows — up to 100 feet (30 meters) lower than previous records,” said Department of Water Resources Director Mark Cowin. “As extensive groundwater pumping continues, the land is sinking more rapidly and this puts nearby infrastructure at greater risk of costly damage.”

Total subsidence in California's San Joaquin Valley for the period May 3, 2014 to Jan. 22, 2015, as measured by Canada's Radarsat-2 satellite. Two large subsidence bowls are evident, centered on Corcoran and south of El Nido. (Canadian Space Agency/NASA/JPL-Caltech)

Total subsidence in California’s San Joaquin Valley for the period May 3, 2014 to Jan. 22, 2015, as measured by Canada’s Radarsat-2 satellite. Two large subsidence bowls are evident, centered on Corcoran and south of El Nido. (Canadian Space Agency/NASA/JPL-Caltech)

«Read the rest of this article»

Sections: Technology | No Comments
 

What is Karst topography and why should you care?

 
karst-map

Karst Hydrology Initiative--Study area showing major karst hydrogeologic settings in the Interior Low Plateaus physiographic region. Areas underlain by Lower-Middle Ordovician limestones shown in brown, and areas underlain by Mississippian limestones shown in green. (USGS Map)

Karst topography describes a landscape abundant in sinkholes, disappearing streams and caves.

According to Dr. Phillip Kemmerly, professor of geology at Austin Peay State University, Clarksville sits in one of the most interesting areas of karst topography in the world.

Clarksville is part of a region known to geologists as the Western Highland Rim Plain. This region includes northern middle Tennessee and extends into western Kentucky where it is called the Pennyroyal Plain and Mammoth Cave Plateau. The only region in the world with more karst features is Slovenia in southern Europe.

Kemmerly divulges that of karst features, sinkholes pose the greatest risk to new and existing construction sites. «Read the rest of this article»

Sections: Education, News | No Comments
 



  • Visit Us On FacebookVisit Us On TwitterVisit Us On GooglePlusVisit Us On PinterestVisit Us On YoutubeCheck Our Feed
  • Personal Controls

    Archives