The ruling on performing wudu' in ponds if their color and taste change

A Yemeni brother residing in al-Madinah al-Munawwarah, whose name is Radwan 'Ali Thabit, asks two questions:
The first question is: We have a pond in our village in Yemen from which people perform wudu', and the water in it has changed in color and taste. Is the wudu' valid or not? We ask for your guidance.
Answer: If the pond is protected from impurities and its change is only due to long standing, then that does not harm. However, if impurities fall into it, or if people use it to clean themselves after defecation or urination, and this causes it to change in taste, smell, or color, then it becomes impure. The scholars have agreed that if water changes in taste, color, or smell due to impurity, it is impure. As for merely performing wudu' from the outside, meaning washing the face and hands without using it for istinja' (cleaning oneself after relieving oneself), this does not harm it. Even if it changes due to long standing, like the water in the wilderness or deserts, where basins in the wilderness or deserts may change due to dust, tree leaves, and other things the wind blows in, that does not harm it. Rather, the water remains pure and sound, even if it changes due to these leaves, dust, or anything else. Yes.