Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock () or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Fred Tillman joined the USGS Arizona Water Science Center in Tucson, AZ in 2006 after two-plus years as a National Research Council (NRC) fellow with the USEPA Office of Research and Development (ORD) in Athens, Georgia.
Prior to joining the USGS, Fred was a post-doctoral researcher with the Ecosystems Research Division of USEPA’s ORD from 2004 through mid-2006, working with Dr. James W. Weaver on issues related to soil vapor intrusion, particularly from leaking underground storage tanks. Fred joined EPA after completion of his doctoral degree in Environmental Engineering at the University of Virginia in 2003, where he worked with Dr. James A. Smith on the response of volatile organic compound (VOC) vapors in the unsaturated zone to natural barometric pressure fluctuations (barometric pumping).
Schematic flowchart showing relations between porphyry copper mining, drought, water resources, ecosystems, health, and economic factors in the Lower Colorado River Basin and adjoining areas
Schematic flowchart showing relations between porphyry copper mining, drought, water resources, ecosystems, health, and economic factors in the Lower Colorado River Basin and adjoining areas
Graphs showing water-year total precipitation and air temperatures in the Lower Colorado River Basin from 1896 to 2019, units modified from millimeters to inches of precipitation and from degrees Celsius to degrees Fahrenheit from: Tillman, F.D., Gangopadhyay, S., and Pruitt, T., 2020, Trends in recent historical and projected climate data for the Colorado River Bas
Graphs showing water-year total precipitation and air temperatures in the Lower Colorado River Basin from 1896 to 2019, units modified from millimeters to inches of precipitation and from degrees Celsius to degrees Fahrenheit from: Tillman, F.D., Gangopadhyay, S., and Pruitt, T., 2020, Trends in recent historical and projected climate data for the Colorado River Bas
Pie chart showing proportions of major water uses (Agricultural, Municipal, Industrial, and Mining) in Arizona, USA, in 2015
Pie chart showing proportions of major water uses (Agricultural, Municipal, Industrial, and Mining) in Arizona, USA, in 2015
Graphs showing trends in atmospheric precipitation and air temperature in the Lower Colorado River Basin, 1896-2019
Graphs showing trends in atmospheric precipitation and air temperature in the Lower Colorado River Basin, 1896-2019
Havasu Creek spilling over Havasu Falls, downstream from Supai Village on the Havasupai Nation.
Havasu Creek spilling over Havasu Falls, downstream from Supai Village on the Havasupai Nation.
This setup is used for processing water-quality samples at Sowats Point on the Kaibab Plateau.
This setup is used for processing water-quality samples at Sowats Point on the Kaibab Plateau.
This view is from Sowats Point on the Kaibab Plateau, looking southwest towards Kanab Creek.
This view is from Sowats Point on the Kaibab Plateau, looking southwest towards Kanab Creek.
Schematic flowchart showing relations between porphyry copper mining, drought, water resources, ecosystems, health, and economic factors in the Lower Colorado River Basin and adjoining areas
Schematic flowchart showing relations between porphyry copper mining, drought, water resources, ecosystems, health, and economic factors in the Lower Colorado River Basin and adjoining areas
Graphs showing water-year total precipitation and air temperatures in the Lower Colorado River Basin from 1896 to 2019, units modified from millimeters to inches of precipitation and from degrees Celsius to degrees Fahrenheit from: Tillman, F.D., Gangopadhyay, S., and Pruitt, T., 2020, Trends in recent historical and projected climate data for the Colorado River Bas
Graphs showing water-year total precipitation and air temperatures in the Lower Colorado River Basin from 1896 to 2019, units modified from millimeters to inches of precipitation and from degrees Celsius to degrees Fahrenheit from: Tillman, F.D., Gangopadhyay, S., and Pruitt, T., 2020, Trends in recent historical and projected climate data for the Colorado River Bas
Pie chart showing proportions of major water uses (Agricultural, Municipal, Industrial, and Mining) in Arizona, USA, in 2015
Pie chart showing proportions of major water uses (Agricultural, Municipal, Industrial, and Mining) in Arizona, USA, in 2015
Graphs showing trends in atmospheric precipitation and air temperature in the Lower Colorado River Basin, 1896-2019
Graphs showing trends in atmospheric precipitation and air temperature in the Lower Colorado River Basin, 1896-2019
Havasu Creek spilling over Havasu Falls, downstream from Supai Village on the Havasupai Nation.
Havasu Creek spilling over Havasu Falls, downstream from Supai Village on the Havasupai Nation.
This setup is used for processing water-quality samples at Sowats Point on the Kaibab Plateau.
This setup is used for processing water-quality samples at Sowats Point on the Kaibab Plateau.
This view is from Sowats Point on the Kaibab Plateau, looking southwest towards Kanab Creek.
This view is from Sowats Point on the Kaibab Plateau, looking southwest towards Kanab Creek.
