What is a headwater stream?
The headwaters of a river system are the small streams and wetlands that are the sources of its water. There are three types of headwater streams: perennial (flowing throughout the year); intermittent (flowing seasonally, when the water table is higher); and ephemeral (flowing only in response to precipitation).
A river system has branches like a tree. And like a tree, the different parts of a river system perform specialized functions. Just as the leaves that feed a tree generally grow on the ends of its branches, and not on its trunk, headwater streams perform functions for which they are uniquely suited.
But though a river system may branch like a tree, it does not regenerate like one. Unlike a healthy tree that responds to pruning by putting its energy into remaining branches and growing new ones, a river system can’t grow new “branches” in the form of ephemeral and intermittent streams, in its upper reaches. And while restoration ecology has made significant advances in recent years, it is still hard to replicate the multi-faceted natural processes of headwater streams.