Is there an environmental Kuznets curve for water use? A panel smooth transition regression approach

► Capturing nonlinearities, the PSTR is an accurate tool to assess the EKC. ► The nexus between per capita water use and income is nonlinear. ► The decreasing trend dominates the “water use per person-per capita GDP” link. ► Income elasticity exhibits great variability in the sample. ► The availability of water and the level of political freedom affect water use.