It was narrated from 'Abdullah bin 'Amr that:
The Messenger of Allah passed by Sa'd when he was performing ablution, and he said: 'What is this extravagance?' He said: 'Can there be any extravagance in ablution?' He said: 'Yes, even if you are on the bank of a flowing river.'" (DE)
English reference (DE): Vol. 1, Book 1, Hadith 425 (DE)
Arabic reference (DE): Book 1, Hadith 460 (DE)