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The controlled splitter must be configured as shown in Figure 2 to ensure that the environmental demand node receives all flow that was ordered. In the model shown in Figure 1, if Environmental Demand 3 orders 200ML, exactly this amount will travel down Default Link #5. Generally, when an environmental demand node forms part of a floodplain, it orders extra water to achieve flooding (for environmental water requirements).
Figure 2. Environmental demand, Controlled splitter characteristics
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