Huge Aquifers Discovered Deep Under Drought-Stricken California

By Nathaniel Scharping | June 27, 2016 3:34 pm

(Credit: M.Khebra/Shutterstock)

In drought-stricken California, a new study finds that there is indeed gold “in them thar hills.”

The gold here, of course, being none other than fresh water, a resource that may well surpass the shiny yellow metal in terms of value as farmers, corporations and average citizens struggle to absorb the impacts of an historic drought that shows few signs of letting up. A new study by researchers from Stanford University plumbs new depths for hints of useable water and seems to have hit the jackpot. The researchers extended their search to depths of almost two miles beneath the surface and report the presence of large aquifers deep below the ground.

That water could come with a price though. California is also home to enticing stores of oil and natural gas, and thousands of wells are currently in operation in the state. Drilling activities directly threaten the health of many of these deep reservoirs, the researchers warn in their paper.

Other Kind of Liquid Gold

The researchers compiled data from the California Division of Oil, Gas and Geothermal Resources, which tracks oil and gas wells around the state. Researchers determined if water had been detected while drilling, and also gathered data about depth, salinity and pressure. After looking at 360 oil and gas fields spread across eight counties, the researchers say that they’ve documented a trove of fresh water just over half the size of Lake Michigan hidden in California’s bedrock 1,000 to nearly 10,000 feet below the surface.

This is almost three times more groundwater than what was indicated in previous studies, many conducted over 20 years ago, and which stopped at a depth of 1,000 feet. Water any deeper than that was considered too expensive to retrieve, and could remain out of reach for the foreseeable future. While the survey extended to around 10,000 feet, the researchers say that much of the water lies closer to the surface, around 3,000 feet deep. The researchers published their work Monday in the Proceedings of the National Academy of Sciences.

A Salty Finding

The researchers defined fresh water as as containing less than 3,000 parts per million (ppm) of dissolved solids. These solids are often salt, but can include other unwanted chemicals, as well. The United States Geological Survey, however, defines fresh water as containing less than 1,000 ppm of dissolved solids. Much of the water found by the researchers, therefore, may require varying levels of treatment. In addition, much of the water is trapped in porous structures in the rock, instead of just sitting underground in giant pools. The dual challenges of extracting and treating the water are indications that these underground aquifers may not be the bonanza they seem to be.

It is clear however, that California must adapt to a drier future, whether that means tapping new sources of water or cutting back consumption. The state used 38 billion gallons of water a day in 2010, which works out to around 1.3 trillion gallons a year. A growing agricultural sector in the state, combined with persistent drought, has only increased the demand for water, and traditional sources of groundwater haven’t kept up with the state’s thirst.


California’s Lake Shasta, photographed in 2014. (Credit: David Greitzer/Shutterstock)

Water Already at Risk

The good news comes with a dark lining, however. Many of the underground aquifers are at risk of being contaminated by oil and gas drilling activities in the region. The wastewater from many wells is injected back into the rocks deep below the surface, where it could leach into untouched reservoirs. Drilling run-off is extremely salty and sometimes filled with other, more harmful, chemicals. If this water breaches uncontaminated aquifers, it could render them unusable.

According to the researchers, 19 percent of the drilling in the counties surveyed occurs in areas that also contain freshwater reservoirs. When dirty water from the wells is forced back into the ground, it causes pressure increases that can allow run-off to spread via faults throughout the bedrock. While most oil wells are deep, if the pressure is sufficient, it will push the water back upwards, toward untouched reserves of fresh water. While researchers couldn’t quantify the actual risk of contamination caused by drilling, they say that their work highlights the need to study previously undocumented deep sources of potentially usable water and protect them.

Crashing Down

Also of concern is the risk of subsidence, or the collapse of the overhead rock, that sometimes occurs when underwater aquifers are drained. When the water is pumped out, what was previously a pool becomes an empty cavern, and if the surrounding rock isn’t stable enough, it can buckle inwards. It’s quite similar to the process that leads to sinkholes, and can similarly lead to major problems for buildings and infrastructure on the surface.

The presence of two lucrative, yet potentially incompatible, resources sitting beneath California’s hills and valleys raises questions for regulators and businessmen alike. Tapping into these reservoirs would be expensive, given how deep they are, but could provide a desperately sought-after answer to the water crisis. Doing so may entail curtailing drilling activities in some regions, however, an option that would likely prove unpopular among the many oil and gas companies already operating in the area.

CATEGORIZED UNDER: Environment, top posts
  • Uncle Al

    Said inexhaustible aquifers are largely brackish. Fresh water head at 1000 ft depth (the old average Central Valley well) is 434 psi. Current wells are running 2000 feet deep, 867 psi, and $400K each. That’s a lot of rice net retained earnings. At 5000 meters depth (3.1 miles depth, the study), 7114 psi and government project funding. Any water so retrieved increases sea level.

    The “good news” is neutralized by Enviro-whiner demands for Environmental Impact Report/well – ground subsidence, salts loading of soils, and destruction of habitat for undiscovered fragile and endangered aquifer organisms. La Niña promises at least coming five years of record-breaking record-breaking drought. Can you say “Anasazi, Chaco Canyon, collapse”?

    • OWilson

      Drilling, mining, pumping, damming, producing, transporting is so, like, yesterday!

      What is better than grazing your own sheep on the common land?

      Embrace the future!

      • Uncle Al

        Support diversity! Ask challenged students what to do, then….no bureaucrat left behind. Million-year old water has nuisance radioactive isotopes all decayed. Super-Kamiokande is 50 kilotonnes of ultrapure water as neutrino and proton-decay detector. Build Hyper-Sacramento as 50 megatonnes of water in kind and on rails, so it can visit Inner City school children who will draw murals on its container.

        • zlop

          Part of North American Trade Agreement,
          Instead of importing ISIS, divert rivers from Canadia.
          Ungava Bay has fresh water on top. There are the
          Fraser and McKenzie Rivers . .. …

  • polistra24

    On the oil and gas, I think you’re underestimating the cleaning power of aquifers. Here in Spokane, the Valley area formerly had no sewer system, so about 70,000 households had septic tanks that drained down into the aquifer. The city’s water system pulled from the same aquifer, just a few miles downstream. It was among the cleanest waters in the country. In the 1990s the Valley finally got a sewer system and the septic tanks were removed. No change in the water quality, but the sudden change in input pressure probably caused a swarm of little earthquakes that were attributed to the aquifer.

  • Wild Bill Kinda

    If it’s good news you can bet someone in California will sue to stop it.

    • Uncle Al

      Governor Moonbeam embraces the financial ontology of taxation plus bond issues, necessary chattel confiscation, utter failure, disappearance of funds into the General Fund. California must embrace Bullet Irrigation: Canadian water hyperlooped into the Sierra snow pack, powered by electric bacteria and monitored with drones.

  • Nunya Bidness

    Didn’t Trump say California had plenty of water a couple of months ago? Wasn’t he mocked for saying so? Given how long it takes for academic research to make in to scientific magazines like Discover, this has been known for quite a while.

    • zlop

      Go Trump Go
      Make America wet again.

  • chloebeckham80

    My colleagues were requiring a form several days ago and found an online platform with an online forms library . If others need it too , here’s

  • Eddie Leong

    It costs $300,000 to drill a 1,000 ft deep well. Imagine how much more it will cost to drill to 3,000 ft or 10,000 ft? It is uneconomical. Yes, we have water at great depths but too costly to drill and to pump out perhaps.

  • Eddie Leong

    Agriculture uses from 65% to 85% of total water resources. Humans uses less than 15% for drinking, washing etc. Agriculture also wastes 50% of the water. The future solution is to find ways to grow food under cover, with recovery of every drop of evaporation. That will be less costly than finding new sources of very deep water.

    With AI, it may be possible to have robots do indoor farming involving LED, tull recovery of water. Than we also need to stop wasting the 30% of harvested food. Truly, the solutions are there for a drastic improvement in water usage.


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