What is the ruling regarding a traveler who possesses water but fears thirst if they use it for ritual purification?

Primary text

It is unanimously agreed upon among the scholars whose views are known that if a traveling person has water but fears thirst (i.e., fears running out of drinking water), they must preserve the water for drinking and perform Tayammum instead. This consensus includes Ali, Ibn Abbas, Al-Hasan, Ata, Mujahid, Tawus, Qatadah, Al-Dahhak, Al-Thawri, Malik, Al-Shafi'i, Ishaq, and the Ashab al-Ra'y. The reasoning is that the person fears harm to themselves from using the water, thus permitting Tayammum, just as applies to a sick person.