Adaptive control of algae detachment in regulated canal networks

Open-channels networks used for water distribution are subject to algal developments that can induce major disturbances such as clogging issues on hydraulic devices (pipes, weirs, filters,...). We already studied the use of flushes to manage these algae developments. The flush is carried out by increasing the hydraulic shear conditions using the hydraulic structures of the canal network. In response to the shear stress increase, a part of the fixed algae is detached, then re-suspended into the water column, and finally transported into the canal network. This leads to a peak of turbidity. We develop in this paper a distributed linear model that is used for real-time adaptive control of the flushes. Simulations show the effectiveness of the adaptive controller, that can at the same time estimate the gain of the system, linked to the amount of fixed algae, and perform a flush without overtopping the turbidity limit.