Oregon Water Science Center
U.S Geological Survey
Oregon Water Science Center
2130 SW 5th Ave
Portland, OR 97201
Phone: (503) 251-3200
Fax: (503) 251-3470
ABOUT THE OREGON WSC
Videos and Podcasts
ABOUT THE USGS
USGS IN YOUR STATE
USGS Water Science Centers are located in each state and territory.
USGS Oregon WSC Highlights
Analyzing the Dynamics of Blue-Green Algae Blooms in an Oregon Reservoir
Willow Creek Reservoir near Heppner, Oregon. Photograph by Bill Johnson, U.S. Army Corps of Engineers.
The occurrence of harmful algal blooms in Oregon and other western states has increased sharply over the past few decades. Blue-green algae blooms in lakes, reservoirs, and rivers have resulted in dog deaths, recreational closures, and concerns about possible algal toxins in water supplies. Health advisories triggered by these blooms have been issued by the Oregon Health Authority on nearly 50 water-bodies in Oregon, from coastal lakes, to rivers, to reservoirs, including the 125 acre Willow Creek Reservoir near Heppner, in eastern Oregon.
Algal bloom in Willow Creek Reservoir near Heppner, Oregon. Photograph by Cassandra Smith, U.S. Geological Survey.
The U.S. Geological Survey and U.S. Army Corps of Engineers are cooperating to understand the spatial dynamics and timing of blue-green algae blooms in Willow Creek Reservoir. The study uses a combination of visual, instrument, and satellite monitoring to assess the ability of these methods to detect the onset of the summer bloom. A monitoring camera will be placed on the dam in the northwest corner of the reservoir, where blooms tend to accumulate owing to prevailing summer winds. The camera will capture images of the reservoir surface every 15 minutes during daylight hours. The reservoir images will be available in near realtime to alert the Corps of when to sample for algal toxins, allowing the Oregon Health Authority to issue timely advisories.
In addition to camera monitoring, the USGS will conduct water sampling in the reservoir during blooms when the camera detects algal accumulation near the dam. Using data from each sampling trip, researchers will produce maps of water temperature, pH, specific conductance, dissolved oxygen, turbidity, and algal-bloom density. LandSat images will augment the water sampling. These maps will help provide the Corps with knowledge of when and where to expect harmful algal blooms in the reservoir.
Blue-Green Algae from Agricultural Drainage Affects Water Quality of the Tualatin River
A floating mat of blue-green algae in the Tualatin River. Photograph by Brian Wegener, Tualatin Riverkeepers, July 17, 2008.
In early July 2008, a large blue-green algae bloom was discovered in the lower Tualatin River, which is a tributary to the Willamette River in northwestern Oregon (fig. 1). Although floating algal mats had occurred approximately 30 years prior, this bloom was the worst in memory for many water-quality scientists and managers familiar with the Tualatin River. This slow-moving, warm, and nutrient-enriched section of river has a long history of water-quality problems related to summer algal blooms through the 1980s. Upgrades in wastewater treatment in the early 1990s greatly diminished the severity of the blooms by capping nutrient levels, and flow augmentation from upstream reservoirs has added dilution and increased water velocity that reduces the time available for blooms to develop. The 2008 bloom, though, was different in many ways.
The USGS, in cooperation with Clean Water Services, traced the source of the bloom to Wapato Lake, an agricultural drain that discharges to the Tualatin River in summer. The bloom provided useful information and lessons for agencies managing public health, wetlands, agricultural activities, and water quality in the Tualatin River basin and similar river basins elsewhere. Results and insights derived from this study can be used to enhance future monitoring and data collection strategies designed to improve water quality and plankton models and better predict dissolved-oxygen concentrations in the lower Tualatin River.
USGS Data Helps Light Up the New Tilikum Crossing Bridge in Portland
Photographs courtesy of TriMet.
On September 10, 2015, the Portland waterfront added a stunning new feature to the city’s nighttime skyline. The Tillikum Crossing bridge showcases a wonderfully artistic amalgamation of art and science every night. Using U.S. Geological Survey water-quality and streamflow data collected from the Willamette River at the Morrison Street Bridge, Portland's TriMet transit service is illuminating the bridge using dynamic lighting based on river velocity, water height, and water temperature. River conditions are translated by specialized software and displayed along the cables and pillars of the new bridge using LED lights. The lights’ base color changes with the river’s temperature. The speed of the colored lights moving across the bridge represents the velocity of the water in the river. Vertical lighting elements up and down the pillars and cables correspond to the height of the water in the river.
USGS Study Explores Geothermal and Groundwater Resources in Parts of Oregon, Idaho, Nevada, and California
Old Perpetual geyser in Lakeview, Oregon, although not a natural geyser, is a manifestation of the geothermal system in the Northwest Volcanic Aquifer Study Area. Photograph courtesy of Lyza Danger Gardiner.
A joint study between the USGS Water and Energy Mission Areas has the main goals of quantifying groundwater resources and geothermal energy potential in much of eastern Oregon, northeastern California, southwestern Idaho, and northernmost Nevada. This study area lies within a broadly-defined Northwest Volcanic Province (NVP) that has been dominated by volcanic eruptions that have shaped the landscape over the past approximately 17 million years. Although the sparsely populated study area has been the subject of relatively little systematic hydrogeologic study, previous geothermal research has identified high geothermal heat flow that may be used to generate large amounts of electricity. In this area, groundwater is the major source of year-round dependable water supply, and water is a necessary component of geothermal energy development. Further, because flowing groundwater moves heat beneath the earth’s surface, interpretation of geothermal heat flow patterns are greatly improved when groundwater flow patterns are taken into account. Read more about the study.
The USGS is working with the U.S. Army Corps of Engineers to Ensure the Survival of Threatened and Endangered Salmonids
The U.S. Army Corps of Engineers manages releases from Detroit Dam for the benefit of threatened and endangered fish. (Photograph courtesy of the U.S. Army Corps of Engineers.)
The North Santiam River drains a large area of the western slope of the Cascade Range in northwestern Oregon and is one of several major tributaries to the Willamette River. Detroit Dam was constructed on the North Santiam River in 1953 by the U.S. Army Corps of Engineers and resulted in the formation of Detroit Lake. Detroit Dam is the tallest dam (463 ft) in the Willamette River Basin and impounds 455,100 acre-ft of water at full pool, making it one of the largest reservoirs in the basin. Detroit Lake is one of the most important hydroelectric and recreational resources among the 13 reservoirs managed by the Corps in the Willamette Valley.
The North Santiam River and its tributaries provide habitat for endangered Upper Willamette River Chinook salmon (Oncorhynchus tshawytscha) and Upper Willamette River winter steelhead (Oncorhynchus mykiss). These species and other salmonids require specific flow and temperature regimes to thrive. To protect and enhance their habitats, the National Marine Fisheries Service wrote a 2008 Willamette Basin Biological Opinion (BiOp) that urges the Corps to assess the feasibility of developing project-specific alternatives for achieving long-term temperature control at the Big Cliff–Detroit Dam complex. The Corps is in the process of evaluating alternatives for both current and long-term downstream temperature management and fish passage at many of the dams in the Willamette Project.
The USGS Oregon Water Science Center is cooperating with the Corps of Engineers to improve downstream temperature conditions for fish in the North Santiam River by using models to determine how operational and structural modifications can affect the temperature regime in the river. Read about the results to date of this study in a recently released report and one released in 2012.
USGS Scientists Are Studying the Causes of Amphibian Declines
A USGS biologist with a bunch of bullfrog tadpoles. Frogs and salamanders worldwide are threatened by the lethal amphibian chytrid fungus, Batrachochytrium dendrobatidis. (Photograph by Charles Crisafulli, U.S. Forest Service.)
With global biodiversity decreasing, it has become important for scientists to find new and innovative tools to quickly assess how environmental hazards affect wildlife, especially threatened or endangered species. This information aids researchers and resource managers alike by providing early detection of potential problems that may require immediate conservation efforts or further detailed investigation. Of all species, amphibians (frogs, toads, salamanders, and newts) appear especially vulnerable to environmental hazards, with up to 41% considered threatened worldwide.
One potentially lethal threat is the amphibian chytrid fungus, Batrachochytrium dendrobatidis, as well as the newly described salamander chytrid fungus, B. salamandrivorans; both cause the disease chytridiomycosis. B. dendrobatidis is linked to many of the observed amphibian population declines and extinctions globally, and B. salamandrivorans has caused recent declines in European salamanders, although it does not yet appear to have made it to North America. A recent study by the U.S. Geological Survey published in the journal PLoS One highlights the use of promising tools that can be used to assess the risk of disease exposure for amphibians. Among the benefits of these tools, scientists have been able to improve survey protocols, which increases the chances of detecting the B. dendrobatidis in the environment while reducing the risk of a false-negative. More importantly, these tools are not limited to only studying B. dendrobatidis. These same methods can be modified to quickly and affordability to provide early detection for diseases like B. salamandrivorans, and study other aquatic diseases that pose risks to the health of wildlife and humans alike.
Study Assesses Groundwater Resources in the Willamette Basin
Irrigation is a major user of groundwater in the Willamette Basin.
Full appropriation of tributary streamflow during summer, a growing population, and agricultural needs are increasing the demand for groundwater in the Willamette Basin. Greater groundwater use could diminish streamflow and create seasonal and long-term declines in groundwater levels. The U.S. Geological Survey and the Oregon Water Resources Department cooperated in a study to develop a conceptual and quantitative understanding of the groundwater-flow system of the Willamette Basin with an emphasis on the Central Willamette subbasin. This final report from the cooperative study describes numerical models of the regional and local groundwater-flow systems and evaluates the effects of pumping on groundwater and surface-water resources. The models described in this report can be used to evaluate the effects of pumping on groundwater, base flow, and stream capture.
The Willamette Basin is a topographic and structural trough that lies between the Coast Range and the Cascade Range in northwestern Oregon. It has five sedimentary subbasins underlain and separated by basalts of the Columbia River Basalt Group (Columbia River basalt) that crop out as local uplands. The regional model covers about 6,700 square miles of the 12,000-square-mile Willamette and adjacent Sandy River drainage basins.
Are Contaminants in the Columbia River System a Cause of Lamprey Declines?
Lamprey male building a redd (spawning nest). (Photograph courtesy of the U.S. Fish and Wildlife Service)
Lampreys are members of an ancient order of jawless, cartilagenous fishes that have existed for as long as 400 million years. Pacific lampreys (Entosphenus tridentatus), one of 38 modern lamprey species, have inhabited Pacific Northwest river basins for possibly millions of years. Pacific lamprey are parasitic on ocean-going fishes, such as salmon. They are integral to the ecology of these river basins, and are culturally significant to several Northwest Tribes. Lamprey populations in the Pacific Northwest and other parts of the world have declined dramatically in recent decades, probably owing to multiple causes. The role of habitat contamination in the declines has rarely been studied and is the main objective of a joint study by the USGS and the Columbia River Intertribal Fish Commission.
The goal of the study is to provide information about the bioaccumulation of several classes of contaminants of concern in larval and adult Pacific lampreys and habitat in key areas of the Columbia River Basin. The study will assess organism health during sensitive life stages before their transformation to adults, compare concentrations in larval tissues to levels in adult lampreys, and consider lamprey and human health implications. Phase 1 of the study, already completed, provided reconnaissance-based information on exposure and bioaccumulation of organic contaminants in larval, filter-feeding lampreys. Phase 2 will concentrate on adult lamprey.
Monitoring Sediment, Bedload, Turbidity and Dissolved Oxygen During Reservoir Drawdown to Facilitate Downstream Fish Passage
Collecting bedload samples in Fall Creek during drawdown of Fall Creek Lake reservoir
The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers (USACE), monitored turbidity, suspended-sediment concentration, dissolved oxygen, and bedload during a short-term operational drawdown of Fall Creek Lake, a reservoir operated by USACE in the upper Willamette Basin, Oregon, in the winter of 2012–13 (fig. 1). The USACE is an action agency listed in the 2008 National Marine Fisheries Service and U.S. Fish and Wildlife Service Biological Opinions (BiOps) on continued operations of the Willamette Valley Project, and, as such, is required to improve conditions at its facilities in the Willamette Basin for Endangered Species Act (ESA)-listed fish species (National Marine Fisheries Service, 2008). The BiOps state that the action agencies must carry out interim operational measures so downstream travelling ESA-listed fish species pass through dams as safely and efficiently as possible until permanent downstream fish passage facilities are constructed. Read about the study and the results.
Modeling Transport of Endangered Upper Klamath Lake Sucker Larvae Through a Restored Wetland
Sucker larvae and an egg collected from Upper Klamath Lake. (Photograph from the USGS Western fisheries Research Center.)
Marshes in the delta of the Williamson River, a major tributary to Upper Klamath Lake in southern Oregon, probably were once among the most important habitats for larvae of the endangered Lost River Sucker, Deltistes luxatus, and Shortnose Sucker, Chasmistes brevirostris, because of their location downstream of productive spawning grounds. In the 1940s, the delta was diked and drained for agriculture, which resulted in loss of organic matter, soil compaction, and subsidence, particularly in the northern part of the delta. In 1996, The Nature Conservancy purchased the property surrounding the mouth of the Williamson River (fig. 1) and began a large-scale restoration project to reconnect the Williamson River with about 6,200 acres of former agricultural land. In October 2007, the levees around the northern part of the delta, known as "Tulana," were breached, flooding approximately 3,700 acres. In November 2008, levees around the southern part of the delta, known as "Goose Bay," were breached, flooding an additional 2,500 acres. A primary restoration goal was to restore the function of the delta and its wetlands as nursery habitat for the endangered suckers.
A hydrodynamic model with particle tracking was used to simulate larval fish dispersal through the Williamson River delta into Upper Klamath Lake before and after restoration. Read about the study results here and here.
How Do Algae Contribute to the Tualatin River Ecosystem?
Pediastrum, a floating colonial green alga. (Photograph by Kurt Carpenter, USGS). Algae like this one produce oxygen and are important to the ecological health of slow-moving rivers like the lower part of the Tualatin River.
Phytoplankton (floating algae) in the Tualatin River of northwestern Oregon are critical for maintaining the river's dissolved oxygen levels in summer. During the low-flow summer period, nutrients and a long residence time typically combine with ample sunshine and warm water to fuel blooms of algae in the low-gradient, slow-moving lower river. Most algae in the lower part of the Tualatin River are the kind that drift with the water because the river is moderately deep and the bottom does not have the type of substrate needed for attached algae. Growth of algae occurs as if on a “conveyor belt” of streamflow, a dynamic system that is continually refreshed with inflowing water. Transit through the system can take as long as 2 weeks during the summer low-flow period. Production of oxygen by algae is important in offsetting oxygen depletion near the river bottom caused by decomposing organic matter from, primarily, the land. Low oxygen concentrations can harm aquatic life.
Recent Oregon WSC Publications
A Method for Characterizing Late-Season Low-Flow Regime in the Upper Grande Ronde River Basin, Oregon, by Valerie J. Kelly and Seth White
Total Dissolved Gas and Water Temperature in the Lower Columbia River, Oregon and Washington, Water Year 2015, by Heather M. Bragg and Matthew W. Johnston
Flood-Inundation Maps for a 9.1-Mile Reach of the Coast Fork Willamette River near Creswell and Goshen, Lane County, Oregon, by Glen W. Hess and Tana L. Haluska
Upstream Factors Affecting Tualatin River Algae—Tracking the 2008 Anabaena Algae Bloom to Wapato Lake, Oregon, by Stewart A. Rounds, Kurt D. Carpenter, Kristel J. Fesler, and Jessica L. Dorsey
Water-Quality Conditions and Suspended-Sediment Transport in the Wilson and Trask Rivers, Northwestern Oregon, Water Years 2012–14, by Steven Sobieszczyk, Heather M. Bragg, and Mark A. Uhrich
Groundwater Levels, Trends, and Relations to Pumping in the Bureau of Reclamation Klamath Project, Oregon and California, by Marshall W. Gannett and Katherine H. Breen
Effects of Groundwater Pumping on Agricultural Drains in the Tule Lake Subbasin, Oregon and California, by Esther M. Pischel and Marshall W. Gannett
Total Dissolved Gas and Water Temperature in the Lower Columbia River, Oregon and Washington, Water Year 2014, by Heather M. Bragg and Matthew W. Johnston
Physical Habitat Monitoring Strategy (PHAMS) for Reach-Scale Restoration Effectiveness Monitoring, by Krista L. Jones, Scott J. O’Daniel, Tim J. Beechie, John Zakrajsek, and Jim G. Webster
Revision and Proposed Modification of a Total Maximum Daily Load Model for Upper Klamath Lake, Oregon, by Susan A. Wherry, Tamara M. Wood, and Chauncey W. Anderson
Simulations of a Hypothetical Temperature Control Structure at Detroit Dam on the North Santiam River, Northwestern Oregon, by Norman L. Buccola and Stewart A. Rounds
Improved Algorithms in the CE–QUAL–W2 Water-Quality Model for Blending Dam Releases to Meet Downstream Water-Temperature Targets, by Stewart A. Rounds and Norman L. Buccola
Geomorphology and Flood-Plain Vegetation of the Sprague and Lower Sycan Rivers, Klamath Basin, Oregon, by Jim E. O’Connor, Patricia F. McDowell, Pollyanna Lind, Christine G. Rasmussen, and Mackenzie K. Keith
Development of a HEC-RAS Temperature Model for the North Santiam River, Northwestern Oregon, by Adam Stonewall and Norman Buccola
Organic Matters— Investigating the Sources, Transport, and Fate of Organic Matter in Fanno Creek, Oregon, by Steven Sobieszczyk, Mackenzie K. Keith, Jami H. Goldman, and Stewart A. Rounds
Water Quality and Algal Conditions in the North Umpqua River, Oregon, 1995–2007, and their Response to Diamond Lake Restoration, by Kurt D. Carpenter and Chauncey W. Anderson, USGS, and Mikeal E. Jones, U.S. Forest Service
Water-Quality Modeling of Klamath Straits Drain Recirculation, a Klamath River Wetland, and 2011 Conditions for the Link River to Keno Dam Reach of the Klamath River, Oregon, by Annett B. Sullivan, USGS; I. Ertugrul Sogutlugil and Michael L. Deas, Watercourse Engineering, Inc.; and Stewart A. Rounds, USGS
Simulation of Groundwater Flow and the Interaction of Groundwater and Surface Water in the Willamette Basin and Central Willamette Subbasin, Oregon, by Nora B. Herrera, Erick R. Burns, and Terrence D. Conlon
Total Dissolved Gas and Water Temperature in the Lower Columbia River, Oregon and Washington, Water Year 2013: Quality-Assurance Data and Comparison to Water-Quality Standards by Heather M. Bragg and Matthew W. Johnston
Assessment of Suspended-Sediment Transport, Bedload, and Dissolved Oxygen during a Short-Term Drawdown of Fall Creek Lake, Oregon, Winter 2012–13, by Liam N. Schenk and Heather M. Bragg
Of Current Interest
How Are Drought and Groundwater Related?
Groundwater is among the Nation's most important natural resources. It provides half our drinking water and is essential to the vitality of agriculture and industry, as well as to the health of rivers, wetlands, and estuaries throughout the country. Droughts can significantly impact the Nation's groundwater resources while the drought is occurring and for some time afterward. Understanding groundwater, surface water, and the integrated nature of the hydrologic system enables resource managers and policy makers to better prepare for and respond to drought. The USGS provides groundwater data and information that resource managers and policy makers can use to prepare for and respond to drought.
Organic Carbon and the World Around Us
Carbon is all around us and in all life on Earth, including us. New analytical methods allow USGS scientists to gain many kinds of information about the sources and fate organic carbon in the aquatic environment, information that can help maintain the health of that environment—and us. Watch this video to learn how.
USGS Helps Debut New Technology to Improve Access and Use of Earth Science Data
Researchers investigating global issues now have an easy method for finding and using earth science data through a new technology developed by the Data Observation Network for Earth, or DataONE.
Understanding broad and complex environmental issues, for example climate change, increasingly relies on the discovery and analysis of massive datasets. But the amount of collected data — from historical field notes to real-time satellite data —means that researchers are now faced with an onslaught of options to locate and integrate information relevant to the issue at hand.
DataONE, a ten-institution team with several hundred Investigators, including researchers from the United States Geological Survey (USGS), is addressing this data dilemma with a number of cyberinfrastructure and educational tools to allow long-term access and usage of earth science data and information. The recently released ONESearch tool queries data centers located around the world for relevant earth science information and provides integrated access to science metadata and corresponding datasets.
Video: What's in Our Water?
This video examines what is in the Nations’ water, how the U.S. Geological Survey monitors it, and the tools the USGS has developed to explore more about our planet’s most abundant resource.
About the USGS Cooperative Water Program
The Cooperative Water Program, the largest of the 28 USGS Bureau Programs, is the Water Mission Area’s “bottom-up, on-the-ground” program that is designed to bring local, State, and Tribal water science needs and decision-making together with USGS national capabilities related to USGS nationally consistent methods and quality assurance; innovative monitoring technology, models, and analysis tools; and robust data management and delivery systems.
The Cooperative Water Program conducts studies in every State, protectorate, and territory of the U.S. through a workforce of about 1,800 people staffed within 48 Water Science Centers in partnership with nearly 1,600 local, State, and Tribal agencies. The Program provides the foundation for USGS strong and robust water monitoring networks (quantity and quality) and supports interpretative studies – about 700 annually – that cover a wide range of issues that are important to the USGS water mission and that inform local, State, and Tribal water decisions.
The significant tie to local, State, and Tribal issues allows the Cooperative Water Program to respond to emerging water issues, raising those issues to regional and national visibility.
Video: Assessing the Health of Our Streams and Rivers
Each year USGS scientists systematically assess the ecological health and water-quality conditions in streams and rivers across the United States. This research plays a vital role in land management and natural resource decisions around the country. These extensive data collection efforts conducted by researchers in the USGS National Water-Quality Assessment Program involve much more than just water quality. Learn more in this video.
US West Coast Erosion Spiked In Winter 2009–10, Previewing Likely Future As Climate Changes
Knowing that the U.S. west coast was battered during the winter before last by a climatic pattern expected more often in the future, scientists have now pieced together a San Diego-to-Seattle assessment of the damage wrought by that winter's extreme waves and higher-than-usual water levels. Getting a better understanding of how the 2009-10 conditions tore away and reshaped shorelines will help coastal experts better predict future changes that may be in store for the Pacific coast, the researchers say.
"The stormy conditions of the 2009-10 El Niño winter eroded the beaches to often unprecedented levels at sites throughout California and vulnerable sites in the Pacific Northwest," said Patrick Barnard, USGS coastal geologist. In California, for example, winter wave energy was 20 percent above average for the years dating back to 1997, resulting in shoreline erosion that exceeded the average by 36 percent, he and his colleagues found.
Read the full USGS news release
Read the journal article
New Discoveries Improve Climate Models
New discoveries on how underwater ridges affect the ocean's circulation system will help improve climate projections.
An underwater ridge can trap the flow of cold, dense water at the bottom of the ocean. Without the ridge, deepwater can flow freely and speed up the ocean circulation pattern, which generally increases the flow of warm surface water.
Warm water on the ocean's surface makes the formation of sea ice difficult. With less ice present to reflect the sun, surface water will absorb more sunlight and continue to warm.
U.S. Geological Survey scientists looked back 3 million years, to the mid-Pliocene warm period, and studied the influence of the North Atlantic Ocean’s Greenland-Scotland Ridge on surface water temperature.
"Sea-surface temperatures in the North Atlantic and Arctic Oceans were much warmer during the mid-Pliocene warm period than they are today, but climate models so far have been unable to fully understand and account for the cause of this large scale of warming," said USGS scientist Marci Robinson. "Our research suggests that a lower height of the Greenland-Scotland Ridge during this geologic age was a contributor to the increase of poleward heat transport."
Read the full USGS news release
Read the journal article
Facing Tomorrow’s Challenges—U.S. Geological Survey Science for the Next Decade
The U.S. Geological Survey responds to evolving national and global priorities by periodically reflecting on and optimizing its strategic science directions. Responding to these national priorities and global trends requires a science strategy that not only builds on existing USGS strengths and partnerships but also demands the innovation made possible by integrating the full breadth and depth of USGS capabilities. The USGS has chosen six science directions that address major challenges for the Nation's future:
Read the Science Strategy Fact Sheet
Read the full report
Global Earthquake Alerts to Include Economic Loss and Casualty Information
Estimated economic loss and casualty information will now be included in earthquake alerts sent out by the U.S. Geological Survey (USGS) following significant earthquakes around the world. These earthquake alerts are widely recognized and used by emergency responders, government and aid officials, and the public to understand the scope of the potential disaster and to develop the best response.
The USGS automated system, PAGER (Prompt Assessment of Global Earthquakes for Response), rapidly assesses earthquake impacts by estimating the shaking distribution, the number of people and settlements exposed to severe shaking, and the range of possible fatalities and economic losses. The estimated losses trigger the appropriate color-coded alert, which determines levels of response: no response needed (green); local or regional (yellow), national (orange) or international (red).
"The two recent earthquakes in Haiti and Chile are good indications that earthquake magnitude alone is not a reliable predictor of human and economic loss,” said Dr. Marcia McNutt, director of the USGS. “The smaller magnitude-7.0 Haiti earthquake caused significantly more damage and loss of life than did the larger magnitude-8.8 Chile earthquake. PAGER is designed to rapidly and automatically take into account the differences in proximity to populated areas, depth of the earthquake, and building standards that are so critical in determining the human and economic toll so that emergency responders can act promptly and accordingly.”
View the entire news release
Read the PAGER fact sheet