See the water-efficient crops: "Know exactly how much water each plant needs"

A large part of the world's agriculture is irrigated with the help of underground reservoirs of groundwater, so-called aquifers.

But more than half of the earth's largest aquifers are overexploited and risk being completely emptied.  

In the Netherlands, many farms have succeeded in reducing their water dependence by 90%.

Part of the solution is greenhouses.

where everything is climate controlled 

- We know exactly how much water each plant needs, says water scientist Arjen Hoekstra, who is now deceased but participates in the documentary The World of Science: H2O - The key to civilization.

Reuses water

The greenhouse retains water that evaporates and reuses it.  

- 99 percent of the water that a plant absorbs from the soil evaporates.

Only one percent is used to build the plant, says Arjen Hoekstra. 

Want to know more about the looming water shortage?

Watch The World of Science: H20 - The key to civilization on SVT Play or Monday 18 January at 20:00 on SVT2.