This thesis explores how the reliance on groundwater has affected the mean level in Ventura California. The efficacy of the Sustainable Groundwater Management Act (SGMA) is examined using an Auto-Regressive Integrated Moving Average (ARIMA) model to better understand the trends of mean groundwater depth. Specifically, mean groundwater depth was analyzed before and after the enactment of the SGMA. The outcomes of this analysis are presented in a bounded fashion where results from the original dataset and a Heckman corrected dataset is used as upper and lower bounds, respectively. In the first observation period, prior to the enactment of the SGMA, the bounded results ranged from a slight deepening to a significant deepening in mean groundwater depth. In the second observation period, after the enactment of the SGMA, the bounded results converged in a significant decrease in the mean groundwater depth in Ventura California. This analysis presents evidence that the SGMA has had a significant effect on reducing the mean groundwater depth and thus mitigating the environmental externalities of chronic groundwater overdraft. Lastly, the metrics and concepts of reporting are explored in terms of how well they report the progress towards sustainable practices.