Challenging hydraulic structures of the twenty-first century – from bubbles, transient turbulence to fish passage

Abstract

Hydraulic structures are man-made waterworks interacting with the rainfall run-off to store and convey water, or mitigate the impact of run-off. Current approaches in hydraulic structure design tend to be conservative, not much differing from ancient designs. Modern structures are often designed based upon simplistic concepts to optimize their performances. However, today’s hydraulic engineers must embrace a number of new challenges, emerging in response to the quickly growing world population, changing climate, evolving agriculture, and growing industrial needs. Herein, new challenges are reviewed using diverse examples of air entrainment at hydraulic structures, transient turbulence during surge events in conveyance structures, and upstream fish passage at road crossings. It is argued that many technical solutions are not satisfactory, e.g. in terms of sustaining aquatic flora and fauna, fluid–structure interactions and operational constraints. Indeed, the current and emerging technical challenges in hydraulic structure design are massive for the twenty-first century hydraulic engineers. The solutions rely upon engineering innovation, excellence in hydraulic research and quality education in universities, complemented by indispensable interactions between engineers, scientists and water stakeholders.