Low-Tech Process-Based Restoration of Riverscapes

Book excerpt: The purpose of this design manual is to provide restoration practitioners with guidelines for implementing a subset of low-tech tools--namely beaver dam analogues (BDAs) and post-assisted log structures (PALS)--for initiating process-based restoration in structurally-starved riverscapes. While the concept of process-based restoration in riverscapes has been advocated for at least two decades, details and specific examples on how to implement it remain sparse. Here, we describe 'low-tech process-based restoration' as a practice of using simple, low unit-cost, structural additions (e.g. wood and beaver dams) to riverscapes to mimic functions and initiate specific processes. Hallmarks of this approach include: - An explicit focus on the processes that a low-tech restoration intervention is meant to promote.- A conscious effort to use cost-effective, low-tech treatments (e.g., hand-built, natural materials, non-engineered, short-term design life-spans) because of the need to efficiently scale-up application.- 'Letting the system do the work', which defers critical decision making to riverscapes and nature's ecosystem engineers.