Urban Water Sensitivity Analysis

Project Dates

The urban water sensitivity analysis (conducted in 1998–1999) examined the impacts of climatic variability and population growth on water supply and demand in five urban areas of Arizona, and highlighted the distinct sensitivities that each of these areas is likely to experience under one-, five-, and ten-year severe drought conditions.

In order to examine the impacts of climatic variability on a variety of water management areas, we chose five sites that vary in population size, type of water demand, and available water resources. The study sites included the Phoenix Active Management Area (AMA), the Tucson AMA, the Santa Cruz AMA, and the Benson and Sierra Vista subwatersheds of the San Pedro River.

The first step of urban water sensitivity analysis was to calculate the impacts of the most severe one-, five-, and ten-year droughts on record if they were to recur today, and at projected 2025 population levels, in order to better understand how increasing population pressure affects the urban water sector. We combined the water supply and demand budgets provided for each region by the Arizona Department of Water Resources with historical records from the Western Regional Climate Center.

The analysis also considered the possible impacts of changes to water supply and demand: supply was altered in some scenarios by eliminating Central Arizona Project (CAP) water, which is drawn from the Colorado River and subject to basin-wide drought; and demand was decreased by eliminating agricultural water use in other scenarios.

Results from this project were split into four categories. Links to the following topics provide a more complete picture of the specific research, methods, and results.