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( NCLPIC) in Lucerne, Colorado. For many years, water sur- <br />face elevations have been monitored at this location using a <br />Steven's recorder and by manually reading the gauge twice <br />per day by the ditch rider. With SCADA, data is transmitted <br />by radio to the central computer on a frequent basis. At the <br />central computer, the data is reported continuously on the <br />HMI screen. NCLPIC is currently investigating full SCADA <br />for improving canal operations and monitoring and report- <br />ing of the company's well augmentation plan. <br />The HMI screen can be, and should be, unique to the user <br />and the circumstance. The screen is simple and intuitive in <br />nature. Radial gate (check structure) positions are depicted <br />graphically, each in a somewhat lower position in the HMI <br />screen, to indicate the canal itself. The operator may raise or <br />lower gates, and therefore water surface elevations in canal <br />pools, by using very small incremental gate movements. <br />Interestingly, Dolores Project staff can and do make changes <br />in their own HMI software interface without assistance from <br />an outside consultant or system integrator. <br />With simple monitoring using a SCADA system, sensors are <br />installed that meet monitoring requirements such as water <br />level sensors. Data is collected on the central system and <br />can then be directly viewed by a system operator or plotted <br />depending on needs and functional requirements. <br />This check structure is controlled by Rubicon gates which are <br />integrated with the SCADA system and used for water surface <br />level control or flow control. <br />6 <br />With remote manual operations, as the <br />name implies, the operator can raise or <br />lower gates and thereby effect the canal <br />operation from the central computer. <br />This is called remote manual because <br />gate movements are implemented by the <br />canal company staff, just as if they were <br />at the gate or check. But gate adjustments <br />can be made much more frequently and <br />therefore canal operations, overall, can <br />become more real time and precise. <br />With local control, the RTU at a particu- <br />lar site is programmed to maintain a set <br />upstream water surface level or to open <br />a gate if a water surface level increases <br />beyond a set point as with a storm event. <br />Full canal automation is possible. This <br />ultimate benefit of SCADA has been <br />widely discussed for two decades but <br />there are actually very few canals oper- <br />ated under what would be called full <br />automation. One note is important here. <br />Some would refer to a canal as being <br />automated with any SCADA implementa- <br />tion, but what they often mean is that the <br />canal is operated under a remote manual <br />scenario using SCADA equipment. For <br />the purposes of this paper, full canal <br />automation means a system in which <br />computer programs control processes <br />from irrigation order inputs through algo- <br />rithm -driven gate adjustment schedules <br />for some future timeframe. This level of <br />automation is not an easily programmed <br />or implemented process. <br />Case Studies <br />Central Arizona <br />The Central Arizona Irrigation and Drain- <br />age District ( CAIDD) has implemented <br />SCADA over much of the district's 60 <br />miles of canal. CAIDD has utilized SCA- <br />DA for many years but it is noteworthy <br />that they have in recent years upgraded <br />their old SCADA system at a relatively <br />