Must the prayers performed with water of doubtful purity be repeated after it is confirmed that it was mixed with sewage water, and is it permissible to use this water for washing without its color having changed?

Water that has changed in color, taste, or smell due to impurity becomes subject to the ruling of impurity, and this ruling is by scholarly consensus.

Therefore, water that has changed due to impure sewage water is considered impure, and purification with it is not valid. Whoever performed ablution with it must repeat all the prayers they performed with that ablution.

Furthermore, it is not permissible to use this impure water for washing, as it will contaminate what is being washed. The smell alone is sufficient to establish its impurity.