Water war is a class war
For some, water is effectively granted as a right, provided at low cost by the state. For many others — usually those who can least afford it — it is treated as a commodity that must be bought. Access to water is in fact much more closely tied to social class than to climate. In this sense, the conflicts arising from water scarcity are class wars.
He also explained that urbanization will be the main cause for water conflict:
First, there are real engineering challenges: the scale and pace of contemporary urbanization is much greater than in the past. And many slums are growing in places vulnerable to catastrophic change: floodplains or steep hillsides.
Second, because urbanization today is in many places occurring without economic growth, governments in the Global South often lack the resources to undertake such large infrastructure projects and are dependent on global markets for financing. But the global political climate today is much less friendly to large state-driven projects.
I have discussed the link between urbanization and water infrastructure here.