May a woman perform tayammum and establish prayer if she cannot find a convenient environment to perform ablution?
If body parts of a woman that are haram to be seen for foreigners will be uncovered while she is performing ablution, she is accepted as not being able to use water and she may perform her prayer by performing tayammum. However, a woman who is in this situation should wait until the end of prayer time to find a suitable environment to perform ablution. If she has concerns that she will miss the prayer time she performs tayammum and then establishes prayer. (Ibn Abidin, Radd al-Muhtar, I, 289-290, 399; Tahtawi, Hashiyah, p. 118)
Source: Presidency Of Religious Affairs The Turkey, High Board of Religious Affairs FATWAS