Hey maybe this would be the perfect time for her ( and you maybe) to move past the water in her face fear. Sometimes children move past their fears and forget to bring the parents along
With my son it was shots. Finally he said one day mom I'm not afraid of getting a shot.
So maybe make it a fun "we get to take showers" time. Kids easily adjust its the parents that have trouble.
Good luck. There is always the wash clothe in the drain trick with a large cup if you don't think that will work.
Buy a blow up bath tub. Right Start & Babies R us sale them for me locally (come in 3 sizes here). I first started using it for my son when he was an infant and now he is 2 and he still has room to grow. It folds up compactly and does not take a long time to blow up. My girlfriend also has one for her 4 year old-- tighter fit but she still gets clean and enjoys playing in it (she uses it at grandmas house who only has a shower & just puts it in the shower stall). We put my sons out on the balcony of our last cruise and enjoyed the scenery while he played