Canal automation in this article refers to closed loop control in which a gate or pump changes its position or setting in response to a water level, flow rate or pressure because the level /rate/pressure is different from the intended target value. Closed Loop means that the action is performed without any human intervention. The automation may be performed though electrical, hydraulic, electronic, or a combination of these.
First canal automation (pre-1950’s) was characterized by the use of hydraulic gates. Flap gates were investigated in The Netherlands by Vlugter at 1940. Cal Poly ITRC has currently reported the history of these gates and a new design procedure for them. Danaidean gates have been used in California since the 1930’s and are still used in many irrigation districts for both automatic upstream and downstream control.
In the 1960’s and 1970’s canal automation in USA proceeded in 4 aspects:
1. Electro-mechanical controller, commonly called “littlemen”, were developed and installed on project throughout the Western US. These controllers legacy continues as many new automated sites with PLC’s retain the old Littlemen logic, with its inherent limitations and simplicity.
2. A few large water conveyance canals are installed with remote monitoring and remote manual control. Most notable is the California Aqueduct, which has been mistakenly identified as an automated facility for decades.
3. A few researchers were willing to develop unsteady open channel flow simulation models, which began to open up possibilities for studying new methods of canal automation.
4. A few researchers and engineers began to try to apply control theory to the actual automation of canals. Perhaps most notable are the early attempt by staff from the US Berau of Reclamation to install HY-FLO and EL-FLO on several canals for downstream control.
A landmark American Society of Civil Engineers specialty conference was held in Portland, Oregon. Entitled “Planning, Operation, Rehabilitation of irrigation Water delivery.