Hydraulic geometry of cohesive lowland rivers

Natural recovery may be extremely slow in cohesive, low-energy, lowland rivers. Therefore, a detailed understanding of the hydraulic properties of the channel is essential when designing restoration or environmental flood management measures. The aim of this study was to increase understanding on the channel size and geometry of cohesive rivers and channels. At-a-site hydraulic geometry of 34 cohesive river and channel reaches in Finland were determined from the field measurements and compared to those determined elsewhere. The computed values of the exponents of the hydraulic geometry were within the range of those presented in the literature and similar between natural and man-made channels. The results indicated that longitudinal channel variation had significant resistance effects during low water.