“We once asked him (abu ‘Abd Allah (a.s.) ,) about a well which is used for Wudu’ and nearby urine flows. ‘Is such a well Najis (unclean)? He (the Imam) replied, ‘If the well is above the place where urine flows below the well and there is a distance of three or four yards in between, it does not make anything of the well Najis (unclean) but if the distance is less than this, the well becomes Najis (unclean). If the well is below the place where water (urine) flows and there is a distance of nine yards between them it does not make the well Najis (unclean). If the distance is less than this then it cannot be used for Wudu’ Zurarah then asked, ‘What happens if the place is steep and urine flows fast and is not stationary on the ground?’ He (the Imam) said, ‘If it is not stationary it is not harmful, and even if a little of it is stationary, it does not make a deep hole in the ground to reach the well and it is not harmful to the well, thus it can be used for Wudu’. It is harmful to the well only when all of it (urine) is absorbed in the ground.’”