1) Water from the hot springs of Teveryah (Tiberias) may not be used for washing one’s hands, as they are bitter and unfit for a dog to drink. However, water from other hot springs which are fit for drinking, may be used. (Shulchan Aruch and Mishne Berura 160)
2) Although one may not wash one’s hands with water from the hot springs of Teveryah (Tiberias), one may however, immerse one’s hands in it when it is still in the spring, and this functions in place of washing one’s hands for a meal. (ibid)