One way is bombing water facilities, as without clean drinking water, Yemenis can't grow food either and will surely die. Almost 2000 Yemeni water installations (dams, barriers, reservoirs) have been completely or partially destroyed by bombs.
The brutal years-long blockade has also prevented the entry of fuel, which means that a large amount of water pumps can't be used.
According to a representative of the UN’s FAO, the war has left around 20 million Yemenis without drinking water:
.With the current conflict, the number of people who don’t have access to clean water is believed to be more than 80% of the population.
Sana`a’s central water tanks were destroyed by US bombs dropped by Saudi warplanes.
In Sana`a, a city of 4 million, the human catastrophe is disastrous. This year, already dozens of water wells in Sana`a Basin have dried up, leaving thousands of people with only access to polluted water, or if they can afford it water at exorbitant prices.
If the war blockade continues, by 2024 at the latest Sanaa won't have access to water:
https://www.mintpressnews.com/can-saudi ... es/278104/Five years from now, the water in the Sana`a Basin will dry up if the war, siege and current practices in the basin continue.