What is the ruling on not fulfilling a vow when its location changes?

A Muslim must fulfill his vow exactly as he made it, in compliance with Allah Almighty’s command: "And let them fulfill their vows," and with the Prophet's (PBUH) saying: "Whoever vows to obey Allah, let him obey Him." It is not permissible to change a vow for someone capable of fulfilling it. Therefore, it is not permissible to place water vowed for the mosque in another location.