Is it obligatory to seek available water even if it causes the prayer time to be missed?
Chapter on Tayammum
Al-Mughni
Book of Purification
Primary text
If water is near a person, attainable by him, but he fears missing the prescribed prayer time if he goes for it, he must strive to reach it and engage in its collection, even if the prayer time consequently lapses. This is because he is considered one who has found water, and thus Teyammum (dry ablution) is not permissible for him, based on the Divine command: {And you find no water, then resort to clean earth} (Quran 5:6).
Supporting text
This opinion is held by Thawri, Al-Shafi'i, and those who follow them.