Definition of meander length in river engineering: The length of a meander is the distance measured along the river between the tangent point of one curve and the tangent point of which subsequent curve?

Introduction / Context:

Meanders are rhythmic, alternating bends in alluvial rivers. Quantifying their geometry—wavelength (meander length), amplitude, and radius of curvature—helps engineers assess planform stability, set corridor widths, and design training measures near infrastructure.

Given Data / Assumptions:

• Planform comprised of alternating bends of comparable scale (same order).
• ‘‘Tangent point’’ refers to the point where the thalweg transitions between bends and the flow aligns momentarily with the valley axis.
• Measurement is along the river centreline (thalweg), not straight-line chord distance.

Concept / Approach:

Meander length (wavelength) is commonly defined as the distance between successive corresponding points on consecutive bends of the same order—e.g., from the tangent point of one right-hand bend to the tangent point of the next right-hand bend downstream. This captures a full meander cycle.

Step-by-Step Solution:

Verification / Alternative check:

Texts illustrate meander geometry with plan sketches showing wavelength as the spacing between corresponding bend apices or tangent points of like bends, confirming the same-order definition.

Why Other Options Are Wrong:

• Immediately following reverse curve: That is half a meander cycle, not the full wavelength.
• Reverse curve plus river width: Not a standard geomorphic definition.
• None of these: Incorrect because the accepted definition is with the next curve of the same order.

Common Pitfalls:

• Measuring straight-line distance rather than along the thalweg.
• Mixing ‘‘same order’’ with immediately reverse bend, leading to underestimation.

Final Answer:

The next curve of the same order