In their April 2010 JAWRA article, “Protecting River Corridors in Vermont,” Michael Kline and Barry Cahoon describe river corridor planning in Vermont, whereby corridors are sized based on the meander belt width and assigned a sensitivity rating based on the likelihood of channel adjustment due to stressors. The approach is fundamentally based on restoring fluvial processes associated with dynamic equilibrium, and associated habitat features.
The authors freely concede Vermont has large geomorphic datasets based on rigorous assessment protocols — Vermont is, after all, a small state — but the techniques seem to have great value nationwide. The article gives examples of how “active” restoration projects to confine a river to a fixed channel have consumed program budgets and required continued investments to correct failures. So Vermont switched to a restoration program that embraces the concepts and practices associated with dynamic and deformable rivers. Thus river corridors are delineated based upon existing and estimated meander belt width. The purpose of a river corridor easement is to give the river the space to re-establish a natural slope, meander pattern, and floodplain connection.
The authors note a passive approach may often be a desirable alternative due to its lower upfront costs and maintenance, but like active restoration, it is highly dependent upon reducing watershed stressors, and landowner willingness to accept changes in land use.
[Please note: I have quoted and paraphrased freely from the article, but the interpretation is my own!]