Semiautomatic design system for river channel cross-sections based on generative design

Abstract A semiautomatic design system for river channel cross-sections is proposed that applies the concept of generative design to nature-oriented river management. The system processes a single representative cross-section of the current reach to generate multiple trapezoidal cross-sections according to the prescribed design parameters and in situ requirements. The cross-sections are then evaluated for flood safety, environmental diversity, and constructability by one-dimensional nonuniform hydraulic simulations, riffle-pool sequence segmentation, and soil volume cutting. As a case study, the design system was applied to two rural rivers with different hydraulic characteristics. The design system took approximately 20 s to generate 100 cross-sections for each river, and the many options and indices helped with the unbiased selection of a reasonable cross-section. The most suitable cross-sections corresponded to those identified by previously developed empirical river restoration methods. For both rivers, the optimal cross-sections differed when the soil volume was considered. The proposed design system is expected to improve the efficiency and effectiveness of river channel design in the context of nature-oriented river management.