There are rules for multiple barriers in the distribution system:
{"Image DocumentName": "There are rules for multiple barriers in the distribution system:", "Image ImageDescription": "And those multiple barriers can be optimized. It is hard to put these in order, because these things are so inter-related. Monitoring is the first step so you know what is in the water. But what you monitor is driven by public health concerns like the possible presence of bacteria and whether the water meets rules for disinfectant and disinfection byproduct levels. I listed disinfection second because it is rather fundamental\u2014all of the water needs protection and disinfection is what we hope provides that. Water age is related to disinfection in that old stagnant water (water with no disinfectant) can lose the disinfection barrier and grow more bacteria, and also fail to disinfect more pathogens that infiltrate the pipe through cracks or cross connections. Water age is also related to dead-end main flushing, because you do that to remove old, degraded water. In terms of specific distribution system barriers, the AWWA also has a helpful list. Some distribution barriers are: Disinfection. Cross connection control. Flushing programs. Water age management. (to avoid stagnation and DBPs) Pressure management. (to avoid leaks) Decorative images: Red \u2018A+\u2019 on lined note paper graphic representing setting goals for excellence, open book graphic representing the rules for drinking water, and highway barrier graphic representing barriers to the presence of contaminants in drinking water.", "Image XResolution": "37", "Image YResolution": "37", "Image ResolutionUnit": "Pixels/Centimeter", "Image Software": "SlidePlayer", "Image YCbCrPositioning": "Centered"}