Municipal Water Use Kuznets Curve

Abstract The relationship between per capita municipal water use (PCMWU) and per capita GDP (PCGDP) (purchasing power parity, constant 2011 US $) are statistically analyzed by country in the world. The results indicate that per capita municipal water use will increase with the rising per capita GDP at the beginning, which will then decrease at a certain threshold (i.e., when per capita GDP reaches a certain level). This trend follows the rules of Water Use Kuznets Curve, i.e., an inverted U-shape curve that describes the relationship between water use and GDP. The cross-sectional analysis of the world country-specific data revealed that, the threshold of PCGDP at the peak point of Kuznets Curve is around 45000 US$. In addition, based on the time-series analysis of developed countries, it is demonstrated that the average threshold of PCGDP at the peak point of Kuznets Curve is 34769 US$. The direct reason for the existence of Municipal Water Use Kuznets Curve is that there is a ceiling of municipal water demand, while the driving forces behind include technological advancements, growth in water prices, effective environmental regulations and policies, and water-saving consciousness. Although PCMWU in most countries of the world are still in an ascending trend, experiences from developed countries present a positive signal, and provide instruments for developing countries.