Interesting. But I don't understand why "first in time" applies to states downstream of the source. The water started as ice melt in Colorado's mountains. So wh

Interesting. But I don't understand why "first in time" applies to states downstream of the source. The water started as ice melt in Colorado's mountains. So why isn't Colorado "first in time?" Is it because in the case of Colorado building a dam, they'd be utilizing the water (instead of just letting it flow), but Arizona was utilizing it before them (by pumping from it to drink)? And if that's the case, then surely Colorado can apply the same logic so long as they have some water facilities powered by the upstream flow? Also, Colorado was settled as a state before Arizona (IIRC), so they must have been using the water before anyone in Arizona was.