Thomas Walski

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Real time modeling and control sounds easy. Get data from the SCADA system, run the appropriate model and push the results back to the controls. What could be difficult about that? Plenty. Anyone attempting to do this work probably has run into some of the institutional, technical and personal hurdles in actually making this sort of system work. This paper will discuss the hurdles and ways to deal with them. The most daunting hurdle is that of security. Most modeling happens on computers connected to the internet. Water utility managers are justifiably terrified of all the bad things that lurk on the internet and want to protect their systems from them. At a minimum, SCADA systems are protected by fire walls, but more aggressive protection is provided by air gaps (sneaker nets) and some have even removed USB ports from computers in control rooms. This leaves modelers struggling to get current data, relying on old massaged data or moving modeling over to the control room side of the air gap. Next is the language barrier. To make real time control work, there groups of people need to communicate: operators, modelers and SCADA managers. But each speaks a unique language and meetings can bog down with each side trying to communicate. There are very few individuals who speak all three languages. Then it becomes necessary to sell modeling to control room operators who see models as an attempt to replace their jobs with a button tied to a computer. Operators need to be sold on the idea that they will do their jobs better but their positions will be safe, while upper management may be actively trying to reduce operator “head count”. This paper will give real world examples of dealing with each of these issues.


Session S1-02, Special Symposium: Real-time Simulation Modeling in Urban Water Systems



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