Meander Geometry and Sinuosity Relationships of Urbanized Beal Slough in Lincoln, Nebraska

In streams and rivers, meanders trend to the form of sine-generated curves. This shape has demonstrated that it is the most hydraulically efficient form for turning water. The perceived relationships between stream width, riffle spacing, meander wavelength and radius of curvature are remarkably consistent for streams and rivers throughout the world. Sinuosity is commonly defined as the ratio of straight valley length to actual length of the stream. In this paper, we define specific meander sinuosity as the ratio of as small as one meander channel length to the straight axis of the particular meander. For the actively remeandering urban reach of Beal Slough, we compared meander radius/bankfull-dominant discharge width ratio and meander wavelength/bankfull-dominant discharge width to specific meander sinuosity. The comparison of historic data of the then rural reach revealed a phase shift between the wavelength/width and radius/width ratios and the specific meander sinuosity. However, the comparison of recent data indicated that the phase shift was not well established. This phase shift of historic data has a striking resemblance to how the channel centerline lags behind the discharge flowline of stream and rivers. Further, these relationships show the promise as acting as predictors of stream health and the qualitative rate of meandering.