Not very often - we're blessed with good streams. I've used it to deepen a spot occasionally. And, I think I know what you're thinking: "You put that into a stream when it's been WHERE?" (I made a similar remark to a proctologist once, when he was bragging about his hand-dipped candy. )

Remember: when I use the trowel, it's to dig an empty hole. When the hole is full, I use a stick to push the dirt back in. That trowel has to go back in my pack, after all!