(Red River Interstate Water Compact allocates water in Red River which divides Oklahoma and Texas which gives signatory states (AR, LA, OK, TX) "equal rights" to excess water in a sub-basin of river with no state entitled to more than 25 percent of excess water no matter where located; TX argued it was entitled to withdraw water from any part of the river including a tributary to take up to 25 percent, including sub-basin within OK and that Compact preempted OK state water law; court disagreed with TX position; TX cannot take water located in OK without OK's permission; OK state law which regulated out-of-state water users not pre-empted by Compact).