Hi, Eze,
Last year in mid April, I was able to cross that arroyo on the tree that was over to the left side. But I was too unsure about stepping and wound up sitting down and sliding across. In retrospect, it would have been much easier to take off my boots and walk across.
We had an all night rain the night I was in Monesterio, and about 10 km outside Fuente de Cantos there was an arroyo that left us no alternative but to take off boots and roll up our pants. Same thing the next day, after Calzadilla de los Barros (which has a very good cafe with home made pastries and last year it didn't have any sort of sign to indicate its presence -- it's on the right, just before the plaza mayor, beyind a little sitting area). Anyway, there were several spots with a fair amount of water after Calzadilla. I got the added enjoyment of having been talking too much with another walker and we missed an arrow and soon saw the Camino on the other side of a huge arroyo, in fact I would say this was more like a small river. With the option being to backtrack a few km, we just waded across. So be careful when leaving Calzadilla, outside town, there is a spot where you have to go up towards the highway and cross the stream, or else you'll be on the wrong side like we were.
So, I guess you are likely to have some water crossing in your future. I think it's worth the few extra minutes to tie your boots to your pack or stuff them inside, or do something to make sure you can use your walking sticks or a branch for support while you're crossing. These stretches are very pretty and the water is not that big a deal. Laurie