New easement program would allow Yellowstone River to roam. (Billings Gazette, 10/19/14). A voluntary channel migration easement program based on channel migration studies would pay Yellowstone streamside landowners to allow the river to freely move across its floodplain.
Channel Migration Processes and Patterns in Western Washington: A Synthesis for Floodplain Management and Restoration This document explains channel migration processes and stream channel patterns in Western Washington, providing a succinct and readable summary of scientific concepts relevant to floodplain management and restoration. As well as posing a hazard to adjacent communities, channel migration is the primary physical process creating biodiversity on floodplains. Channel Migration Zones (CMZs) can therefore provide a vital tool for achieving multiple benefits in floodplain management decisions. As well as providing fundamental concepts for floodplain management and restoration, this document supports mapping of CMZs required for communities updating their Shoreline Master Programs.
Channel Migration Studies: Approach and Policy
Vermont Applies Fluvial Geomorphic Science in Managing Rivers and Floodplains as a Functioning System The state of Vermont has set performance-based standards for stream equilibrium and connectivity, river corridor protection, and compensatory flood storage, all of which promote the fluvial processes that connect rivers and floodplains as one functioning riparian system. The River Corridor Base Map provides fluvial erosion hazard mapping data and protections for over 5,200 miles of Vermont rivers and streams as described in the state’s newly adopted Flood Hazard Area and River Corridor Rules and Procedures.
Washington State Department of Ecology's Shoreline Master Program (SMP) Guidelines include requirements for new shoreline master programs to address channel migration zones (CMZs). Requirements in the Guidelines to address channel migration do not change the statutorily defined shoreline jurisdiction. Areas that could legitimately be considered within the CMZ of a river may extend beyond shoreline jurisdiction.
Washington Department of Ecology CMZ Resource Website This web site provides a scientific method of analysis designed to identify channel migration zones (CMZs) based on historic patterns, and hydrologic and geomorphic factors inline with the Shoreline Master Program (SMP) Guidelines. The Washington State site includes:
A step-by-step process to develop channel migration maps, reinforced with flow charts.
Methods for determining when a CMZ assessment is needed.
Multiple approaches for doing a CMZ analysis, based on the desired level of effort and depth of analysis needed.
Completed CMZ assessments examples.
A hazard rating system to help in the development of shoreline management policies to protect public safety and reduce flood hazards (currently being developed).
A Methodology for Delineating Planning-Level Channel Migration Zones The Washington State administrative codes that implement the Shoreline Management Act (SMA) require communities to identify the general location of channel migration zones, and regulate development within these areas on shoreline streams. The SMA and its administrative codes provide no guidance on planning-level CMZ delineation methods. The Washington Department of Ecology developed a planning-level CMZ delineation (pCMZ) method to support local communities’ updates and implementation of the SMA requirements. This document describes the pCMZ approach in context of Washington State regulations.
The Vermont Agency of Natural Resources’ Rivers Program promotes the planning, designing, and protecting of river corridors that will accommodate stream meander and floodplain processes as the most economically and environmentally sustainable river management alternative.
Upper Missouri Headwaters River/Flood Hazard Map Development This is an application to the Montana Reclamation Development Grant Program (RDGP) from May 2012. It was submitted by Ruby Valley Conservation District and funded by the Montana State Legislature. This project will develop channel migration studies and maps for approximately 510 river miles on six rivers: Gallatin, East Gallatin, Beaverhead, Madison, Jefferson, and Ruby Rivers. These river reaches were selected through a prioritization process that included population/development pressures, need, interest, and coordination with Department of Natural Resources and Conservation Floodplain Mapping Program. The letter of support from the state Water Operations Bureau identifies this study as a crucial state need.
