This is a CLD On plastic packaging recycling at a household scale. A causal loop diagram (CLD) is a diagram that shows how different variables in a system are causally interconnected. The diagram is made up of words and arrows. Causal loop diagrams are accompanied by a narrative that explains the causally closed situation described by the CLD. Closed loops, or causal feedback loops in the diagram, are critical characteristics of CLDs. EdrawMax lets you create CLD diagrams in easy steps.