San Pedro River reports & data

San Pedro River Wet-Dry Maps (October 2016)

The San Pedro River wet/dry mapping dataset is a community effort to track the river’s health by monitoring the persistence of surface water during the driest time of each year. It is created by recording the end points of every wet section of the San Pedro River during June each year. Maps depict the wet portion of the San Pedro River.

San Pedro River Wet/Dry Map Animation (October 2016)

Every June groups of volunteers walk the entire 170 mile length of the San Pedro River and record where it is wet and where it is dry during the hottest, driest time of the year. Sixteen years’ worth of data on summertime surface flows in the San Pedro River within the San Pedro Riparian National Conservation Area (SPRNCA) are now available as an animation. Watch to see the changes in surface flow over time. These observations were recorded by citizen scientists through the Wet/Dry Mapping project- a collaboration between TNC and the Bureau of Land Management on this particular reach of the San Pedro River.  Follow this link to see what they found from 1999 to 2015 on the approximately 50 miles of the San Pedro River that flows through the SPRNCA.

Notes about the data and animation:

  1. Use the play, pause, and advance buttons at the bottom to view the animation.

  2. Use the plus or minus keys to zoom in on portions of the river.

  3. Survey dates varied from year to year, but have been standardized to June 29 for purposes of this animation.

  4. Although the animation time scale at the bottom indicates a one year date range, the data shown is actually the annual standardized June 29th survey date. To make the scale date appear as that one point in time, click on and drag one of the time markers on top of the other.

Go to the animation

Wet/Dry Mapping: Using Citizen Scientists to Monitor the Extent of Perennial Surface Flow (February 2011)

Published in Environmental Management, this article describes a simple method for monitoring the flow status of interrupted perennial streams, with the example of a 12-year effort on the San Pedro River. We found that surface flow increased for parts of the river, apparently due to conservation actions, while other parts were stable or may have declined. The data allowed us to map areas with surface flow in every year, totaling 32% of the river length through the San Pedro Riparian National Conservation Area (SPRNCA). These maps show areas with high year-to-year variation in flow length, which indicate changes in local groundwater conditions and may provide early warning of ecological changes.

Download file (1 MB)

Wet/Dry Mapping Instructions and Data Forms (April 2011)

Example wet/dry mapping instructions and data forms used for the San Pedro wet/dry mapping effort. For more information, see our wet/dry mapping page.

Sustainable Water Management in the Southwestern United States: Reality or Rhetoric? (July 2010)

Published in PLoS ONE, this study used four scenarios to explore the potential effects of alternative growth and water management strategies on river flows. Under the base population projection, we found that rivers in seven of the 18 study watersheds could be dewatered due to municipal demand. Our approach provides a low-cost method to identify where alternative water and growth management strategies may have the most impact, and demonstrates that such strategies can maintain a continued water supply for both people and the environment.

Download file (1 MB)

Integrating science and policy for water management (April 2009)

This chapter, from Ecology and Conservation of the San Pedro River (edited by J. Stromberg and B. Tellman), provides an in-depth treatment of the collaborative effort of scientists, agency representatives, non-governmental organizations, elected officials, and other stakeholders and the role of adaptive management in addressing water policy and management issues in the Sierra Vista subwatershed of the upper San Pedro River.

Download file (4 MB)

San Pedro River Watershed Maps (October 2008)

Series of 4 map exhibits illustrating conservation-related data on the status of this internationally-recognized desert river and riparian corridor. Maps include both the U.S. and Mexico portions of the San Pedro watershed depicting the following themes: Conservation Investments; Riparian Ecological Condition; Current and Formerly Perennial Stream Reaches; and a Water Budget.

Download file (21 MB)

Participatory Learning on the San Pedro River: Designing the Crystal Ball Together (July 2006)

Published in the July/August 2006 issue of Southwest Hydrology, this paper outlines the key building blocks for sustainable water management in the upper San Pedro River. It describes the role of the public–private consortium - the Upper San Pedro Partnership, the development of information and scientific tools to help answer key questions and identify tradeoffs in water management alternatives, and the importance of cooperation, collaboration and commitment of scientists, stakeholders and elected officials.

Download file (1 MB)

Interbasin Groundwater Flow at the Benson Narrows, Arizona (March 2005)

Describes research indicating groundwater is moving through the floodplain alluvial aquifer at Three Links Farm, and that most of this water originates from the Upper San Pedro River Basin. Published in March/April 2005 issue of Southwest Hydrology.

Download file (< 1 MB)

The Lower San Pedro River—Hydrology and Flow Restoration for Biodiversity Conservation (May 2004)

Describes The Nature Conservancy’s flow management approach to increasing water supply for riparian vegetation, based largely on results from hydrologic analyses indicating that retiring agricultural pumping at key locations increases water availability for riparian vegetation. Paper presented at USFS conference, May 11-15, 2004.

Download file (< 1 MB)

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