Unified Interior Regions
Arizona
The Southwest Region includes California, Nevada, and Arizona. The Regional Office, headquartered in Sacramento, provides Center oversight and support, facilitates internal and external collaborations, and works to further USGS strategic science directions.
States L2 Landing Page Tabs
AzWSC Capabilities: Hydrologic Gravity Monitoring
Gravity is a measurement of mass: the greater an object's mass, the stronger its gravitational pull. By measuring changes in gravity over time, inferences can be made about changes in mass. In hydrology, this can be used to study water in the subsurface. If the amount of groundwater in a particular area increases over time, through processes such as infiltration of rainfall or aquifer recharge...
Process-based Approaches for Ecological Restoration of Degraded Drylands
Surface disturbances ranging from military training, recreation, energy exploration and development, and wildfires impact a large majority of federal lands in the western US, but the ecological and economic impacts are poorly understood. Explore this webpage to learn how Dr. Lesley DeFalco and her research team are currently evaluating and refining conventional approaches for post-fire...
Native Plant Materials for Ecological Restoration of Degraded Drylands
There is a growing consensus among resource managers to use native plant materials for ecological restoration of degraded drylands. Some plant species may be suitable for re-introduction across broad environmental gradients. Other species may fail under narrower conditions, or their re-introduction may have genetic consequences for local ecotypes, particularly when adapting to future climate...
Conservation of Rare, Sensitive, and At-risk Desert Plant Species
The Mojave Desert is among the hottest and driest of the North American drylands, but in spite of these extreme conditions, and in part because of them, a diverse flora exists. This diversity of rare, endemic, and endangered species is threatened by the complex interaction between fluctuating climate and human-mediated disturbances. USGS studies have identified rare species “hotspots” for...
Colorado Plateaus Regional Groundwater Availability
Pilot phase
This study is in a pilot phase during fiscal years 2017 and 2018. The purpose of the pilot phase is to identify possible technical challenges of using the USGS code GSFLOW for simulating groundwater and surface-water flow in the Colorado Plateau principal aquifer system. During the pilot phase, the project will evaluate GSFLOW in the San Juan River Basin (...
Land Treatment Digital Library
The LTDL was created by the U.S. Geological Survey (USGS) to catalog information about land treatments on Federal lands in the western United States for all interested parties. The flexible framework of the library allows for the storage of a wide variety of data in different formats. The LTDL currently stores previously established land treatments or what often are called legacy data. The...
RestoreNet: Distributed Field Trial Network for Dryland Restoration
U.S. Geological Survey (USGS) researchers and land managers are co-producing a network of restoration field trial sites on DOI and surrounding lands in the southwestern U.S. The network systematically tests restoration treatments across a broad range of landscape, soil, and climate conditions. Each site in the network is used to test suitable seed mixes and treatments that promote plant...
Occurrence and Potential Risk of Microplastics in Lake Mead and the Delaware River
There is mounting evidence that microplastics present a significant threat to aquatic organisms. Microplastics – defined as plastic particles less than 5 mm in diameter – come from many different sources, including synthetic textiles, industrial waste products, personal care products, and the breakdown of litter, car tires, and other objects. This study will assess the occurrence of...
National Water-Quality Program Monitoring Networks, Arizona, 2013-2023
The Arizona Water Science Center collects water-quality data from stream and aquifer sites in networks that are part of the National Water-Quality Program (NWQP) and the National Stream Quality Accounting Network (NASQAN).
Ecosystem Modelling and Decision Support
The Ecosystem Modelling and Decision Support Project seeks to understand how drivers of ecosystem change like wildfire, drought, and land use affected past spatial and temporal patterns of vegetation communities and wildlife. Research methods involve 1) analyzing field-collected information (e.g. long-term plot/transect data, repeat photography) on soils, vegetation, and/or wildlife with...
Hydrocarbon Monitoring in Response to Personal Watercraft Regulation at Glen Canyon National Recreation Area
Polycyclic aromatic hydrocarbon (PAH) contamination related to watercraft use is one of the most significant water-quality issues affecting Lake Powell at Glen Canyon National Recreation Area (GLCA). Water quality in Lake Powell is important as the lake is a water source for public and agricultural consumption. In addition, more than 2 million people visit GLCA annually, and most of these...
Identification and Analysis of Points of Diversion along the Lower Colorado River in Support of Decree Accounting
In the United States, the Colorado River Compact of 1922 apportions the waters of the Colorado River between the upper basin States and the lower basin States (U.S. Congress, 1948, p. A17-A22). The requirement for participation of the U.S. Geological Survey (USGS) and the Bureau of Reclamation (BOR) is stated in Article V. Water in the lower Colorado River is apportioned among the States of...
Progress report on the ground-water, surface-water, and quality- of-water monitoring program, Black Mesa Area, northeastern Arizona; 1987-88
The Black Mesa, Arizona, monitoring program is designed to determine long-term effects on the water resources of the area resulting from withdrawals of groundwater from the N aquifer by the strip-mining operation of Peabody Coal Company. Withdrawals by Peabody Coal Company increased from 95 acre-ft in 1968 to 3 ,832 acre-ft in 1987. The N aquifer...
Hart, R.J.; Sottilare, J.P.Simulation of five ground-water withdrawal projections for the Black Mesa area, Navajo and Hopi Indian Reservations, Arizona
The N Aquifer is the main source of water in the 5,400 sq mi Black Mesa area in the Navajo and Hopi Indian Reservations in northeastern Arizona. Water in the aquifer is under confined conditions in the central 3,300 sq mi of the area. Maximum saturated thickness is about 1,050 ft. Annual groundwater withdrawals from 1972 through 1986 averaged 5,...
Brown, J.G.; Eychaner, J.H.Estimates of average annual tributary inflow to the lower Colorado River, Hoover Dam to Mexico
Estimates of tributary inflow by basin or area and by surface water or groundwater are presented in this report and itemized by subreaches in tabular form. Total estimated average annual tributary inflow to the Colorado River between Hoover Dam and Mexico, excluding the measured tributaries, is 96,000 acre-ft or about 1% of the 7.5 million acre-ft...
Owen-Joyce, Sandra J.Progress report on the ground-water, surface-water, and quality-of-water monitoring program, Black Mesa area, northeastern Arizona, 1987
The N aquifer is an important source of water in the 5,400 sq-mi Black Mesa area on the Navajo and Hopi Indian Reservations. The Black Mesa monitoring program is designed to monitor long-term effects on the groundwater resources of the mesa as a result of withdrawals from the aquifer by the strip-mining operation of Peabody Coal Company....
Hill, G.W.; Sottilare, J.P.Annual summary of ground-water conditions in Arizona, spring 1984 to spring 1985
In arid and semiarid regions such as Arizona, the availability of adequate water supplies has a significant influence on the type and extent of economic development. About two-thirds of the water used in the State is groundwater. The nature and extent of the groundwater reservoirs must be known for proper management of this valuable resource. The...
Evapotranspiration estimates using remote-sensing data, Parker and Palo Verde valleys, Arizona and California
In 1981 the U.S. Geological Survey established an experimental project to assess the possible and practical use of remote sensing data to estimate evapotranspiration as an approximation of consumptive use in the lower Colorado River flood plain. The project area was in Parker Valley, Arizona. The approach selected was to measure the areas covered...
Raymond, L.H.; Rezin, K.V.Progress report on Black Mesa monitoring program; 1985-86
Hill, George W.; Whetten, Marlin I.Annual summary of ground-water conditions in Arizona, Spring 1983 to Spring 1984
A summary map shows various aspects of groundwater availability in Arizona. Potential well production, in increments of 0 to 10 gpm, 10 to 500 gpm, and 50 to 2500 gpm (average 1000 gpm) os the primary emphasis of the map; however, data on changes in water level from spring 1983 to spring 1984, status of groundwater inventory, and estimated...
Progress report on Black Mesa monitoring program, 1984
The N aquifer is an important source of water in the 5,400 square-mile Black Mesa area on the Navajo and Hopi Indian Reservations. The project is designed to monitor long-term effects on the ground-water resources of the mesa as a result of withdrawals from the aquifer by a strip-mining operation. Withdrawals from the N aquifer by the mine have...
Hill, G.W.A method for estimating ground-water return flow to the Colorado River in the Palo Verde-Cibola area, California and Arizona
Owen-Joyce, Sandra J.A method for estimating ground-water return flow to the Colorado River in the Parker area, Arizona and California
Leake, S.A.Annual summary of ground-water conditions in Arizona, spring 1982 to spring 1983
The withdrawal of ground water was slightly less than 4.2 million acre-feet in Arizona in 1982, which is about 1.2 million acre-feet less than the amount withdrawn in 1981. Most of the decrease in 1982 was in the amount of ground water used for irrigation in the Basin and Range lowlands province. Through 1982, slightly more than 193 million acre-...
Measuring Water Levels in a Flowing Well
This video demonstrates how to measure low pressure hydraulic head in a flowing well.
Cloud Lightning
What looks like lightning arcing through an ominous cloud is actually a dry landscape of rocky buttes in southern Utah and northeastern Arizona. River channels flow north from Arizona into the San Juan River. The light vertical feature at the top of the image is referred to as Comb Ridge, a jagged fold in the Earth's crust called a monocline.
- Collection: Earth
Hurricane Odile, AZ Flooding September 2014, USGS at Work
This video shows the flooding that occurred in Arizona from the remnants of Hurricane Odile, while explaining the different techniques for high flow measurements.
Measuring Groundwater with Steel Tape
This video demonstrates how to measure water levels in wells using a graduated steel tape.
Measuring Groundwater with Electric Tape
This video demonstrates how to measure water levels in wells using an electric tape.
Redington Stream Flow
This video shows the process of taking a stream flow measurement using a bridge crane and current meter.
Changes in Earth's Gravity Reveal Changes in Groundwater Storage
Did you know that changes in the amount of water in aquifers cause small changes in Earth’s gravitational field? When the amount of groundwater in an aquifer changes, either by recharge or by discharge to surface water or wells, the gravitational acceleration at the land surface also changes. In this photo, USGS Research Hydrologist Jeff Kennedy is making measurements of
...Minute 319 Pulse Flow
The minute 319 pulse flow experiment flood in the Lower Colorado River Delta allows scientists the opportunity to study many different aspects of a flood. With the help of CSAs we had the opportunity to actually back calculate the roughness value at the times that our technicians in Yuma measured discharge.
Gravity Recharge Monitoring
Time-lapse Microgravity Monitoring of Artificial Recharge
This video shows a series of clips collected in 2013 during the SAVSARP gravity experiment.
Animal Interactions at Wind Energy Facilities – Gray Fox
There were two documented gray fox visits at the burrows, making them the third most documented predator. Gray foxes are implicated predators of various life stages of desert tortoises, but it is difficult to catch them in the act. In this case, a gray fox approaches a burrow, and thoroughly investigates the burrow mouth. The fox develops an arch in its tail (slight
Animal Interactions at Wind Energy Facilities – Western Spotted Skunk
There was one documented skunk event captured on camera - the least documented predator. Here, a western spotted skunk is thoroughly investigating the burrow of one of the marked female tortoises in the study population. Western spotted skunks are known predators of turtle eggs. The skunk investigated the area within the burrow for a full minute before it appears outside
TESNAR Program: CSAs
TESNAR stands for the Technical training in Support of Native American Relations, and is a program run by the USGS to foster cooperation between tribes and the USGS by providing them with the tools and training to manage their tribal resources, such as water. As shown here, training in the Continuous Slope Area Method can help tribes a great deal, by providing data when
FLAGSTAFF, Ariz. — Experts in volcano hazards and public safety have started a conversation about volcanoes in the southwestern United States, and how best to prepare for future activity. Prior to this meeting, emergency response planning for volcanic unrest in the region had received little attention by federal or state agencies.
Dr. Justin Hagerty, a research geologist with the U.S. Geological Survey, was named one of President Obama's recipients of the Presidential Early Career Award for Scientists and Engineers, the highest honor bestowed by the United States government on science and engineering professionals in the early stages of their independent research careers.
TUCSON, Ariz. —On Wednesday, the U.S. Geological Survey finished installing six early-flood-warning units—rain and stream gages—in the burned areas of New Mexico’s Whitewater-Baldy Fire. The gages transmit data via satellite to the National Weather Service, which provides warnings to communities that may be affected by flooding. The gages can provide up to 60 minutes advanc
FLAGSTAFF, Ariz. — Laszlo Kestay has been named the new director of the U.S. Geological Survey Astrogeology Science Center, based in Flagstaff, Ariz. Kestay will lead the Astrogeology team in working closely with NASA and other planetary science organizations to develop and operate space missions exploring the Solar System, process and analyze data from many types of instruments...
FLAGSTAFF, Ariz. — Coconino National Forest’s Cinder Lake—a natural depression that has been used to store runoff from areas affected by the 2010 Schultz Fire—can store about 4,000 acre-feet of water, or enough to fill about 2,000 Olympic-sized swimming pools, according to a new U.S. Geological Survey report.
TUCSON, Ariz. – Climate change is likely to have strong effects on the abundance of dominant Sonoran Desert plant species, according to a study published recently in Global Change Biology.
The U.S. Geological Survey has named ecologist David Lytle the director of its Southwest Biological Science Center, headquartered in Flagstaff.
“Rapid growth, changes in land use, and limited rainfall in the southwest region of the U.S. create challenges for natural resource management,” remarked USGS director Marcia McNutt.
More than 280 million acre-feet of groundwater has been withdrawn from the Mississippi embayment aquifer system between 1870-2007, according to a new water modeling tool developed by the U.S. Geological Survey.
The sand dunes among which Navajos have eked out austere livings for generations are growing fast and becoming mobile as the climate changes, says U.S. Geological Survey geologist Dr. Margaret Hiza Redsteer, whose interviews with elders and historical research augment her decade-long research on Navajo Nation land.
FLAGSTAFF, Ariz. – The sand dunes among which Navajos have eked out austere livings for generations are growing fast and becoming mobile as the climate changes, says U.S. Geological Survey geologist Dr. Margaret Hiza Redsteer, whose interviews with elders and historical research augment her decade-long research on Navajo Nation land.
A dust storm that rolled across the Arizona desert on Tuesday, October 4, 2011, effectively blinded motorists, leading to a large string of motor vehicle crashes, multiple injuries, and at least one death.
Over the last 70 years, groundwater in Arizona's alluvial basins was depleted by more than 74.5 million acre-feet, or approximately three times the maximum storage of Lake Powell.