Both red-footed and yellow-footed tortoises have a diet unusually rich in protein and as such they must always have access to fresh drinking and soaking water, and must be provided with high humidity in their enclosure. It is no coincidence that all tortoises who have these dietary requirements occur in very humid ecosystems. Dehydration is always a very serious danger to tortoises with a high protein diet, and if untreated tap water is all that is available it is certainly better than none at all. However, distilled water is preferred and I would also advise you to use a conditioner such as ZooMed ReptiSafe or JurassiSafe to remove excess chlorine and ammonia. If this is not possible, water should be left to stand for 48 hours before use for excess chlorine to dissipate.