The initial survey classified landscapes with scores of 60 or higher as xeriscapes. Questions remained after the study about whether the test to classify xeriscapes was valid, if sample bias existed, and the impact of xeriscapes on water use. Water demand equations were modeled using regression analysis. Data on the price of water, minimum charges, lot sizes, rainfall, temperature, income, the number of persons per household, and the use of an irrigation system were analyzed without using the xeriscape classification system, which was analyzed separately. The landscape test was shown to be a valid measure of xeriscapes.
Higher scores show that more xeriscape principles are being used correctly.
The tests indicated that two distinct populations were sampled in the first study. This means that comparisons between those with xeriscapes and those that do not use them can't be performed without more socioeconomic data. As a result, the focus shifted to only those who implemented xeriscapes. Homeowners with xeriscapes decreased their household water use by 2,024 gpm. Households that install xeriscapes typically have higher incomes than those who do not and are less sensitive to the price of water.