Recreation Visits to Lake Mead and Glen Canyon National Recreation Areas: A Replication Study

This thesis conducted a replication study of an earlier analysis of the relationship between lake volumes and monthly recreation visits to Lake Mead and Glen Canyon (Lake Powell) National Recreation Areas. The exact same data that were used in the original study were no longer available, but similar data were available from the same government agency sources used in the original study. For the years of the original study, 1996 to 2011, the basic results of the original study hold in the replication. These were that (i) lake volume was significantly and positively associated with visits, (ii) the effect of volume had different seasonal effects for Lake Powell, but not Lake Mead, and (iii) there were strong monthly seasonality in visitation patterns. The main results of the original study – the strong positive impact of lake volume on visits – was not robust when extending the period of analysis from 1979 to 2017. When additional economic variables were added to the regression model, a positive effect of lake volume was found for Lake Powell from 1996-2017, but not from 1979-2017, or 1979-1995. A significant positive relationship between volume and visits was not found for Lake Mead for 1979-1995, 1996-2017, or the entire period 1979-2017. Throughout out all regression specifications, gasoline price, which was omitted from the previous study, had a statistically significant negative effect on visits. This effect was robust across all time intervals and across both lakes.