أَوْ يُصْبِحَ مَاؤُهَا غَوْرًا فَلَنْ تَسْتَطِيعَ لَهُ طَلَبًا

Surah Al-Kahf : 41
Or its water will become sunken [into the earth], so you would never be able to seek it."

Main.lang.desc.tafsir:ayahs:h2