Sacramento, California - One third of veggies and two thirds of fruits and nuts in the US come from the severely parched state of California, but the delicious crops are in danger of further water shortages due to damaged groundwater reserves.

A recent study funded by the University of California Research Initiatives (UCRI) announced that groundwater reserves in California haven't been replenished fast enough to keep up with the state's water use.

Researchers used data pulled from NASA's GRACE satellites, which rely on minute changes in the pull of gravity over different parts of the planet. In parts where there is less matter – due to chronic groundwater loss, for example – there is a slightly lower gravitational force, which the satellites can pick up.

The water shortage is due to a necessary practice in the Golden State, where agriculture and urban water demands are met by tapping into groundwater supplies during drier periods.

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This would normally be no problem, because when the rain returns, it can top up the aquifers. However, decades of droughts and acute water mismanagement have prevented groundwater reserves from returning to healthier levels.

The researchers also found that there may not be enough refills anytime soon, even with new policies enacted to save water.

The very best case scenario for refilling groundwater reserves in California could take up to six to eight years, but the current climate and rainfall trends make a projected timeframe of up to two decades much more likely.

New water-saving measures and time are the ingredients needed to heal California's aquifers, while the extreme drought problems in California are expected to worsen as climate change continues.