That doesn't work. People locally will decide that people far away should pay the costs while locals reap the rewards. People upriver will use all of the water

That doesn't work. People locally will decide that people far away should pay the costs while locals reap the rewards. People upriver will use all of the water. People in fertile, temperate, not low lying areas will be affected less by climate change and burning fossil fuels. If the wind blows east, people to the west won't care about smog until made to care by force. And so on.