GEOPHYSICAL MONOGRAPH SERIES, VOL. 194, PP. 69-93, 2011
Natural Channel Design: Fundamental Concepts, Assumptions, and Methods
The natural channel design (NCD) approach to river restoration emulates natural river systems and was initially developed
to help redirect the manner in which past traditional river works have impacted natural river systems. The NCD approach integrates
fluvial processes over temporal and spatial scales of self-formed and self-maintained natural rivers. Landscapes and stream
systems must be observed in light of their evolution or successional states through various stages of adjustment. In doing
so, the processes that produce a stable reference reach morphology can be inferred through time trends of river change. To
understand the cause and consequence of change becomes a formidable yet essential phase in this NCD process; thus, rigorous
protocols are necessary to document field observations and complete a consistent, quantitative, comparative assessment. NCD
requires an understanding of process and form relations that must be formally quantified, tested, designed, and monitored.
Over 67 form variables must be predicted in NCD that cannot be accurately predicted using current analytical models, which
currently contain an incomplete system of equations. However, analog, empirical, and analytical methods are applied in NCD
to determine and test the design variables. This chapter explains the underlying fundamental principles and concepts of NCD,
definitions, assumptions, ecological integration, prediction methodologies, and minimum application requirements required
for a sustainable design that strives to meet multiple objectives.
Citation: Rosgen, D. L. (2011), Natural channel design: Fundamental concepts, assumptions, and methods, in Stream Restoration in Dynamic Fluvial Systems: Scientific Approaches, Analyses, and Tools, Geophys. Monogr. Ser., vol. 194, edited by