Abstract
This study employs the Super-SBM model to evaluate the green efficiency of agricultural water use (GEAW) at the municipal level across China from 2013 to 2022. Urbanization levels are systematically assessed using the entropy weight method. Grounded in this theoretical framework, we employ a two-way fixed effects regression model to estimate the effect of urbanization on GEAW and to examine whether government water conservancy infrastructure investment intensity (GOVE) moderates this relationship. The findings of this study indicate that: (1) China’s GEAW exhibited a fluctuating downward trend, with pronounced regional disparities. Geographically, the distribution exhibited a clear trend: elevated levels in the eastern and southern regions, contrasted with lower values in the western and northern areas. (2) The urbanization process is positively associated with GEAW. (3) The urbanization process exerts a heterogeneous promoting effect on GEAW contingent upon GOVE; a single-threshold effect is empirically identified. Specifically, when GOVE remains below the threshold level, the urbanization process exhibits no statistically significant positive impact on GEAW. However, once investment surpasses this critical threshold, the urbanization level (URBA) begins to exert a robust and positive influence on such efficiency. Therefore, within the broader context of ongoing urbanization, it is imperative to actively foster coordinated green development between urban and rural areas and optimize governmental investment strategies for water infrastructure—particularly through differentiated, targeted, and evidence-based governance approaches—thereby establishing favorable external conditions conducive to enhancing GEAW and advancing the modernization of agriculture.