The Wastewater Treatment Facility is a complex process involving dozens of pumps, hundreds of valves and millions of gallons of wastewater. All this process is monitored and controlled by a centralized computer based network.
The operator on duty can monitor which pumps are running, how much water they are pumping, which valves are open or closed, how much chlorine is being applied and even which lift stations in the city are currently pumping. By recording this information in databases, the operating staff can then analyze it and determine which is the best way to optimize treatment in the facility for any given situation.
With all these complex systems and moving parts there is a lot that can go wrong. It's the job of the maintenance crew to fix the problems when they happen and to anticipate future problem before they occur. The maintenance crew handles everything from rebuilding a broken pump or replacing a valve to fashioning new replacement parts and mowing the grass.
In any complex system, no matter how well controlled it is, if there is poor maintenance things will grind to a halt fairly quickly.