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Available Water: Sum of available water in allocation account balance and carry over account balance. Each account has two account balance, one is to record allocation balance, the other is to record allocated carryover water balance which is carried over from last water season. Not all the water in these two account balance are available for use, some water can be reserved for special purpose, such as spilling. Only available component can be used by water user.
If If "Water Available While Spillable" is enabled,
Available water = Account balance + Carryover Water; which means all water in these two account balance are available for use
Otherwise,
Available water = Account balance + Carryover Water - spillable Water; which means some water (spillable water component) are reserved and not available for use
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