|Kepner, W. - US-EPA|
|Bassett, S. - DESERT RESEARCH INSTITUTE|
|Mouat, D - DESERT RESEARCH INSTITUTE|
Submitted to: Environmental Monitoring and Assessment
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: February 1, 2004
Publication Date: June 1, 2004
Citation: Kepner, W.G., Semmens, D.J., Bassett, S., Mouat, D.A., Goodrich, D.C. 2004. Scenario analysis for the san pedro river, analyzing hydrological consequences of a future environment. Journal of Environmental Monitoring and Asessment 94:115-127. Interpretive Summary: The semi-arid southwest United States and northern Mexico are experiencing continued pressure from rapid population growth. Census projections over the next 30 years indicate continued growth in this region that far exceeds population growth in other parts of the United States. Water is a critical resource in these regions and is often in short supply. To plan for this change and its impacts of basin water resources it is valuable for decision-makers to examine future land use and land cover patterns that would likely result from various growth and planning assumptions. In this study, alternative future land cover and land use patterns based on various planning and zoning scenarios were examined relative to their impact on surface water conditions (surface runoff and sediment yield) within the San Pedro River Basin which originates in Sonora, Mexico and flows into southeast Arizona. The study employs tools and models developed jointly by USDA-ARS, US-EPA, and the University of Arizona. The change in runoff and sediment from a baseline year of 2000 to 2020 was computed in such a way that impacts of this change can be analyzed and visualized over the entire basin. This allows stakeholders and decision-makers to rapidly evaluate how and where different planning and growth scenarios will impact runoff and erosion.
Technical Abstract: Studies of future management and policy options based on different assumptions provide a mechanism to examine possible outcomes and especially their likely benefits and consequences. The San Pedro River in Arizona and Sonora, Mexico is an area that has undergone rapid changes in land use and cover and subsequently is facing keen environmental crises related to water resources. It is the location of a number of studies that have dealt with change analysis, watershed condition, and most recently, alternative futures analysis. The previous work has primarily dealt with resources of habitat, visual quality, and groundwater related to human development patterns and preferences. In the present study, future options were examined relative to their impact on surface water conditions, e.g. surface runoff and sediment yield. These hydrological outputs were estimated for the baseline year of 2000 and predicted twenty years in the future using hydrological process models and spatially oriented land use models based on stakeholder preferences and historical growth.