Costa Rica is indeed the land of many rivers. Where I live is no exception.

With the highest mountain (Cerro Chirripo at 12,533 feet) less than an hours drive away and the beach only about half that time, you can imagine that there are many Costa Rica rivers running through it. And sometimes quite ferociously at that.

That’s the main attraction of Perez Zeledon for this Costa Rica Guy.

In May I visited one of my favorite waterfalls in the area, Nauyaca Falls.

It is one of most beautiful I’ve seen in all of Costa Rica and also, usually, one of the best for swimming and diving off the rocks.

You can do the falls in one of two ways, by horse or by foot. I have written in the past about the horse-back option.

By foot, the predominantly mild hike is around 45 minutes. There can be a lot of mud during the rainy season as the trail doubles as a horse path.

You may see some animals, such as white-faced monkeys and toucans along the way.

It began lightly raining as we embarked on the hike. That might should have been taken as an omen of what was to come.

When we arrived, the fall was certainly pumping harder than during dry season months (December through April), but not too strong and still with its normal beautiful turquoise green color.

When we first entered the water it was possible to swim up to the fall, climb up the first level of rock ledge and dive off.

We did that a few times, then just rested there, taking in all of nature’s beauty.

In a flash the water turned rust brown and the fall began pumping at an alarmingly strong rate. I decided to get the heck out of there and dove in. The current heading downstream was overwhelming. I would have been taken right down the river to who knows where if I had not been able to get a hand-hold on a rock near the place where we would normally exit the water.

What had just happened is what in Costa Rica is referred to as a “cabeza de agua.” I believe in English the appropriate term is flash flood. It is not an uncommon experience in the wet season. They can be deadly.

The thing is while it had been raining a bit at first, well into the hike the sun came out and by the time we reached the fall, it was completely dry.

Doesn’t matter. A cabeza de agua doesn’t occur due to rain where you are, it’s what’s happening up there in the high mountains that causes this phenomenon. And up there it could be raining cats and dogs and you’d never know it.

So, if you’re in Cost Rica during the rainy season, be careful with those gorgeous Costa Rica rivers…they can turn dangerous in a flash!