The existing literature simply concludes that the irrational behaviors of local people and natural factors are the major reasons for overuse of groundwater. Using the OLS and ARIMA (BJ) Statistical Methods and Trend Analyses, this article finds that government policy, as measured by four proxy variables, is a very important factor that strongly influences the overuse of groundwater at the collective level. This means the government is a very important actor in the game of groundwater usage. Although these findings cannot clearly separate government effects from local effects, using a Trend Analysis, they reveal that these significant effects are strictly consistent with variations in government policy. Moreover, they show that government policy effective at the county level strongly impacts the overuse of ground-water by influencing the behavior of the local people and that policy at the operative level impacts four policy domains: population, cultivated land, water assignments and peasant income.