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At least 865 records · Page 48Linked to original sources

Collaborative hubs: Making the most of predictive epidemic modeling

The COVID-19 pandemic has made it clear that epidemic models play an important role in how governments and the public understand and respond to infectious disease crises. In the early days of the COVID-19 pandemic, models were used first to estimate the true number of infections, then to provide estimates of key parameters, to generate short-term forecasts of outbreak trends, and to quantify the possible effects of different interventions on the unfolding epidemic. In contrast to the central coordinating role played by major national or international agencies in weather-related emergencies, pandemic modeling efforts were initially scattered across many individual research institutions and academic groups. Differences in modeling approaches and assumptions of each individual effort led to contrasting results that at times contributed to confusion in public perception of the pandemic. For this reason, recent efforts to publicly coordinate modeling efforts in so-called “hubs” have provided governments, public health partners, and the public with assessments and forecasts that reflect the consensus (or lack thereof) in the modeling community. This has been achieved by openly and transparently synthesizing uncertainties across different individual modeling approaches and facilitating comparisons between them.

American Journal of Public Health↗

Are waterfowl food resources limited during spring migration? A bioenergetic assessment of playas in Nebraska's rainwater basin

Accurate bioenergetic carrying capacity estimates of wetlands on public and private lands, as well as those managed for crop production are important for managing waterfowl populations and habitats. Given the importance of wetlands in the Rainwater Basin region of Nebraska for spring migrating waterfowl, we quantified and compared seed and aquatic invertebrate biomass and true metabolizable energy (TME) at three wetland types; public wetlands, wetlands enrolled in the Wetlands Reserve Program (WRP), and cropped wetlands. Median seed biomass estimates at public, WRP, and cropped wetlands were 593kg/ha, 561kg/ha, and 419kg/ha respectively. Cumulative TME varied among wetland type, with greater TME at cropped wetlands (2,431kcal/kg) than public (1,740kcal/kg) and WRP wetlands (1,781kcal/kg). Seed biomass estimates from this study were statistically greater than those currently used for management planning in the RWB, however, TME estimates were statistically lower than estimates currently assumed for WRP and public wetlands. Our estimates for aquatic invertebrate biomass were approximately 40-fold less than seed biomass estimates. Based on spring ponding frequency at wetlands in Nebraska’s Rainwater Basin, and the caloric estimates derived for each wetland type, we concluded that the regions wetlands meet the energetic demand of spring migrating waterfowl during 10% of years.

Nebraska↗

Wildfire risk information sources and the acceptability of fuels treatments near select WUI communities in the Western United States

Fuels treatments intended to reduce fuel loads and improve forest health on public lands offer one way to reduce wildfire hazards in the wildland-urban interface (WUI), where the natural and built environments meet. However, for fuels treatment implementation to be successful, it must comply with regulatory and scientific standards and be supported by local communities, as lack of acceptance can lead to alterations, delays, or abandonment. To foster support, public land managers can engage directly with residents in communities near treatment areas through various communication channels or engage indirectly through trusted local partners. This research uses paired household survey and observed parcel-level wildfire risk assessment data to investigate wildfire risk information sources' role in the acceptability of fuels treatment approaches on public lands near select WUI communities in the Western United States. We find that information deemed useful from sources is often positively correlated with acceptability, while information deemed not useful is sometimes negatively correlated. Local sources of information tend to be widely received, perceived as useful, and have positive correlations with acceptability, while nonlocal sources vary in their receipt, perceived usefulness, and correlations with acceptability. Public land managers, particularly those from national organizations, may benefit from leveraging and aligning messaging with trusted local partners. Developing fuels treatment plans that consider existing local sentiments may facilitate public trust in managers and acceptability of treatments.

Colorado, New Mexico, Oregon, Washington, Wyoming↗

Nowcasting methods for determining microbiological water quality at recreational beaches and drinking-water source waters

Nowcasts are tools used to provide timely and accurate water-quality assessments of threats to drinking-water and recreational resources from fecal contamination or cyanobacterial harmful algal blooms. They use mathematical models and techniques to provide near-real-time estimates of fecal-indicator bacteria (FIB) and cyanotoxin concentrations. Techniques include logic-based thresholds, decision trees (built with machine learning), multiple linear and binary logistic regression, artificial neural networks, and process-based deterministic models. The type of site (freshwater, marine, or river) and dependent variable (FIB or cyanotoxin) dictate which explanatory variables are used in models. Nowcast systems notify the public of associated public-health risks and can also be used to manage data for FIB models; work is ongoing to incorporate cyanotoxin models into some nowcasts. The Great Lakes NowCast in the USA has been operational since 2010 and includes 25 lake beaches and one recreational river site. Examples of other operational FIB nowcasts are described for locations in the USA and around the world. In many cases, models predicted exceedances of FIB standards with accuracies as good as or better than using the previous measured FIB concentration (persistence method). Accuracy and timeliness are vital to beach management decisions that protect public health and support the local recreation-driven economy. Nowcasts benefit the public by providing estimates of water-quality conditions in near-real-time. Managers can use nowcasts at recreational and drinking-water treatment plant sites when FIB or cyanotoxins are projected to be elevated to target sample collection, to provide near-real-time recreational advisories to the public, or to preemptively optimize drinking-water treatments or change intake options to mitigate possible adverse effects on drinking-water quality.

Journal of Microbiological Methods↗

Lithium in groundwater used for drinking-water supply in the United States

Lithium concentrations in untreated groundwater from 1464 public-supply wells and 1676 domestic-supply wells distributed across 33 principal aquifers in the United States were evaluated for spatial variations and possible explanatory factors. Concentrations nationwide ranged from <1 to 396 μg/L (median of 8.1) for public supply wells and <1 to 1700 μg/L (median of 6 μg/L) for domestic supply wells. For context, lithium concentrations were compared to a Health Based Screening Level (HBSL, 10 μg/L) and a drinking-water only threshold (60 μg/L). These thresholds were exceeded in 45% and 9% of samples from public-supply wells and in 37% and 6% from domestic-supply wells, respectively. However, exceedances and median concentrations ranged broadly across geographic regions and principal aquifers. Concentrations were highest in arid regions and older groundwater, particularly in unconsolidated clastic aquifers and sandstones, and lowest in carbonate-rock aquifers, consistent with differences in lithium abundance among major lithologies and rock weathering extent. The median concentration for public-supply wells in the unconsolidated clastic High Plains aquifer (central United States) was 24.6 μg/L; 24% of the wells exceeded the drinking-water only threshold and 86% exceeded the HBSL. Other unconsolidated clastic aquifers in the arid West had exceedance rates comparable to the High Plains aquifer, whereas no public supply wells in the Biscayne aquifer (southern Florida) exceeded either threshold, and the highest concentration in that aquifer was 2.6 μg/L. Multiple lines of evidence indicate natural sources for the lithium concentrations; however, anthropogenic sources may be important in the future because of the rapid increase of lithium battery use and subsequent disposal. Geochemical models demonstrate that extensive evaporation, mineral dissolution, cation exchange, and mixing with geothermal waters or brines may account for the observed lithium and associated constituent concentrations, with the latter two processes as major contributing factors.

Science of the Total Environment↗

The future of scientific communication in the earth sciences: The impact of the internet

Publication on paper of research results following peer-review and editing has been the accepted means of scientific communication for several centuries. Today, the continued growth in the volume of scientific literature, the increased unit costs of archiving paper publications, and the rapidly increasing power and availability of electronic technology are creating tremendous pressures on traditional scientific communication. The earth sciences are not immune from these pressures, and the role of the traditional publication as the primary means of communication is rapidly changing. Electronic publications and network technology are radically altering the relationship between interpretative result and the underlying data. Earth science research institutions, including the Kansas Geological Survey, are experimenting with new forms of on-line publication that assure broad access to research and data and improve application of research results to societal problems. ?? 1997 Elsevier Science Ltd.

Computers & Geosciences↗

Ground‐water problems in Ohio, with special reference to the industrial area of Cincinnati in Butler and Hamilton counties

The importance of ground‐water as a natural resource to be used for water‐supply and industrial purposes is often overlooked by the general public. A recent survey conducted by the Engineering News‐Record [see 1 of “References” at end of paper], based on data obtained from State Sanitary engineers, shows that 9,100 out of a total of 12,700 public water‐supply systems in the United States obtain water from underground sources. Of the total population served by public water‐supplies, about 28 per cent or 22,500,000 people are served by systems using ground‐water. In addition to the quantities of water pumped for public supplies, many million gallons of ground‐water are pumped daily for rural, domestic, and industrial purposes. In many of the cities that have public supplies from surface‐sources, there is nevertheless heavy pumping from private wells for industrial purposes.

Ohio↗

Ground-water models: Validate or invalidate

The word validation has a clear meaning to both the scientific community and the general public. Within the scientific community the validation of scientific theory has been the subject of philosophical debate. The philosopher of science, Karl Popper, argued that scientific theory cannot be validated, only invalidated. Popper’s view is not the only opinion in this debate; however, many scientists today agree with Popper (including the authors). To the general public, proclaiming that a ground-water model is validated carries with it an aura of correctness that we do not believe many of us who model would claim. We can place all the caveats we wish, but the public has its own understanding of what the word implies. Using the word valid with respect to models misleads the public; verification carries with it similar connotations as far as the public is concerned. Our point is this: using the terms validation and verification are misleading, at best. These terms should be abandoned by the ground-water community.

Ground Water↗

Contrasting water quality from paired domestic/public supply wells, central High Plains

Closely located domestic and public supply wells were sampled using identical sampling procedures to allow comparison of water quality associated with well type. Water samples from 15 pairs of wells with similar screened intervals completed in the central High Plains regional aquifer in parts of Kansas, Oklahoma, and Texas were analyzed for more than 200 water quality constituents. No statistically significant differences were observed between the concentrations of naturally-derived constituents (major ions, trace elements, and radon) in paired wells. However, differences in water quality between paired wells were observed for selected anthrepogenic compounds (pesticides and tritium), in that some public supply wells produced water that was more recently recharged and contained constituents derived from surface activities. The presence of recently recharged water and compounds indicative of anthrepogenic activities in some public supply wells was likely due to operational variations (pumping rate and pumping cycles), as demonstrated in a particle tracking simulation. Water containing surface-derived anthropogenic compounds from near the water table was more quickly drawn to high volume public supply wells (less than five years) than domestic wells (greater than 120 years) with small pumping rates. These findings indicate that water quality samples collected from different well types in the same area are not necessarily directly comparable. Sampling domestic wells provides the best broad-scale assessment of water quality in this aquifer setting because they are less susceptible to localized contamination from near the water table. However, sampiing public supply wells better represents the quality of the used resource because of the population served.

Kansas, Oklahoma, Texas↗

Status and performance of the ShakeAlert® earthquake early warning system: 2019-2023

The U.S. Geological Survey (USGS)‐operated ShakeAlert® system is the United States West Coast earthquake early warning system ( Given et al. , 2018 ). In this study we detail ShakeAlert’s performance during some of the largest events seen by the system thus far. Statewide public alerting using ShakeAlert messages was authorized in California in October 2019. Over the next few years, public alerts were expanded into Oregon and then into Washington ( U.S. Geological Survey, 2024 ). ShakeAlert source results are routinely compared to the USGS Comprehensive Catalog (ComCat; Guy et al. , 2015 ; U.S. Geological Survey, Earthquake Hazards Program, 2017 ), which contains the earthquake location and magnitude determined using complete waveform data. M 4.5 and larger is the threshold used for public alerting and was deliberately set below the level where damage is likely to compensate for cases where the system underestimates the magnitude. Between 17 October 2019 and 1 September 2023, the ShakeAlert system created 95 events with maximum magnitude estimates of M ≥4.5, the public alerting threshold. 94 of the 95 events were due to real earthquakes. Seven were categorized “false” per ShakeAlert’s internal definition that there was no matching catalog event within 100 km and 30 s of origin time; however, all but one of these were real earthquakes that were poorly located, primarily because they were at the edges of the seismic network. Three detected events were labeled “missed” because they were very poorly located (>100 km location error). In addition, the system did not produce solutions for four ComCat events M ≥4.5 ( U.S. Geological Survey, Earthquake Hazards Program, 2017 ), which were all at the edge of the alerting and network boundaries. The ShakeAlert system has accurately detected the majority of earthquakes that have occurred within the operational region since completing the public rollout, and alerts from the system have been delivered to millions of cell phone users throughout the West Coast.

California, Oregon, Washington↗

Contributions to economic geology, 1902

This bulletin has been prepared primarily with a view to securing prompt publication of the economic results of investigations by the United States Geological Survey. It is designed to meet the wants of the busy man, and is so condensed that he will be able to obtain results and conclusions with a minimum expenditure of time and energy. It also affords a better idea of the work which the Survey as an organization is-carrying on for the direct advancement of mining interests throughout the country than can readily be obtained from the more voluminous reports. Should this bulletin be favorably received by those interested in the development of the mineral industries of the United States, it is proposed to publish early in each calendar year a similar bulletin containing the results of the last year's field work in economic geology. In the preparation of the present volume, promptness of publication has been made secondary only to the economic utility of the material presented. The papers included are such only as have a direct economic bearing, all questions of purely scientific interest being excluded. The papers represent three classes : (1) Preliminary discussions of the results of extended economic investigations, which will later be published by the Survey in more detailed form; (2) comparatively detailed descriptions of occurrences of economic interest, noted by geologists of the Survey in the course of their field work, but not of sufficient importance to necessitate a later and more extended description; (3) abstracts of certain economic papers which have appeared in Survey publications during the last year, chiefly such as give a general account of the distribution and mode of occurrence of particular mineral deposits throughout the United States. The papers have been grouped according to the subjects treated. At the end of each section is given a list of previous publications on that subject by this Survey. These lists will be found serviceable by those who wish to ascertain what has been accomplished by the Survey in the investigation of any particular group of mineral products. They are generally confined to Survey publications, though a few titles of important papers published elsewhere by members of the Survey are included.

Bulletin↗

Overview of the Texas Source Water Assessment Project

The 1996 Amendments to the Safe Drinking Water Act require, for the first time, that each state prepare a source water assessment for all PWS. Previously, Federal regulations focused on sampling and enforcement with emphasis on the quality of delivered water. These Amendments emphasize the importance of protecting the source water. States are required to determine the drinking-water source, the origin of contaminants monitored or the potential contaminants to be monitored, and the intrinsic susceptibility of the source water. Under the amendments to the Act, States must create SWAP Programs. The programs must include an individual source water assessment for each public water system regulated by the State. These assessments will determine whether an individual drinking water source is susceptible to contamination. During 1997?99, TNRCC and USGS staff met as subject-matter working groups to develop an approach to conducting Source Water Susceptibility Assessments (SWSA) and a draft workplan. The draft workplan was then presented to and reviewed by various stakeholder and technical advisory groups. Comments and suggestions from these groups were considered, and a final workplan was produced and presented to the EPA. After EPA approval, work formally began on the Texas SWAP Project. The project has an expected completion date of September 2002. At that time, initial SWSA of all Texas public water supplies should be complete. Ground-water supplies can be considered susceptible if a possible source of contamination (PSOC) exists in the contributing area for the public-supply well field or spring, the contaminant travel time to the well field or spring is short, and the soil zone, vadose zone, and aquifer-matrix materials are unlikely to adequately attenuate the contaminants associated with the PSOC. In addition, particular types of land use/cover within the contributing area may cause the supply to be deemed more susceptible to contamination. Finally, detection of various classes of constituents in water from wells in the vicinity of a public supply well may indicate susceptibility of the public-supply well even though there may be no identifiable PSOC or land use activity. Surface-water supplies are by nature susceptible to contamination from both point and non-point sources. The degree of susceptibility of a PWS to contamination can vary and is a function of the environmental setting, water and wastewater management practices, and land use/cover within a water supply's contributing watershed area. For example, a PWS intake downstream from extensive urban development may be more susceptible to non-point source contamination than a PWS intake downstream from a forested, relatively undeveloped watershed. Surface-water supplies are also susceptible to contamination from point sources, which may include permitted discharges, as well as accidental spills or other introduction of contaminants.

Texas↗

Distribution of Elevated Nitrate Concentrations in Ground Water in Washington State

More than 60 percent of the population of Washington State uses ground water for their drinking and cooking needs. Nitrate concentrations in ground water are elevated in parts of the State as a result of various land-use practices, including fertilizer application, dairy operations and ranching, and septic-system use. Shallow wells generally are more vulnerable to nitrate contamination than deeper wells (Williamson and others, 1998; Ebbert and others, 2000). In order to protect public health, the Washington State Department of Health requires that public water systems regularly measure nitrate in their wells. Public water systems serving more than 25 people collect water samples at least annually; systems serving from 2 to 14 people collect water samples at least every 3 years. Private well owners serving one residence may be required to sample when the well is first drilled, but are unregulated after that. As a result, limited information is available to citizens and public health officials about potential exposure to elevated nitrate concentrations for people whose primary drinking-water sources are private wells. The U.S. Geological Survey and Washington State Department of Health collaborated to examine water-quality data from public water systems and develop models that calculate the probability of detecting elevated nitrate concentrations in ground water. Maps were then developed to estimate ground water vulnerability to nitrate in areas where limited data are available.

Fact Sheet↗

Scientific information in support of water resource management of the Big River area, Rhode Island

The Rhode Island Water Resources Board (RIWRB) is concerned that the demand for water may exceed the available public water supply in central and southern Rhode Island. Although water is often assumed to be plentiful in Rhode Island because of abundant rainfall, an adequate supply of water is not always available everywhere in the state during dry periods. Concerns that water demand may exceed supply are greatest during the summer, when lower water levels and increased drought potential combine with seasonal increases in peak water demand (Rhode Island Water Resources Board, 2012). High summer water demands are due to increases in outdoor water use, such as lawn watering and agricultural irrigation, and to increased summer population in coastal areas. Water-supply concerns are particularly acute in central and southern Rhode Island, where groundwater is the primary source of drinking water. The Big River and Mishnock River Basins are subbasins of the South Branch of the Pawtuxet River Basin in central and southern Rhode Island. These basins&mdash;referred to together as &ldquo;the Big River area&rdquo; for the purposes of this report&mdash;are undeveloped relative to other nearby areas and provide a potential source of high-quality public drinking water for central and southern Rhode Island. After the severe drought of the 1960s, the State of Rhode Island acquired land in the Big River area with the intention of building a water-supply reservoir. The reservoir was not built because of concerns over potential environmental impacts and projected statewide water-supply needs (U.S. Environmental Protection Agency, 1989). The land acquired for the reservoir (13.4 mi 2 ), called the Big River Management Area (BRMA), is currently managed by the RIWRB as a future source for public water supply and as open space. In the 1980s, the RIWRB began to consider whether the BRMA could supply water from its aquifers (groundwater). Groundwater withdrawals for public or other water-supply needs can alter the hydrologic conditions and ecologic communities of surrounding rivers, lakes, and wetlands by removing water from these systems. Consequently, the RIWRB was interested in determining optimal amounts of groundwater that could be withdrawn from the BRMA for public supply while minimizing the effects on rivers, lakes, streams, and wetlands that also rely on this water. For nearly two decades, the RIWRB has conducted a series of cooperative studies with the U.S. Geological Survey (USGS). The goals of these studies have been to (1) evaluate and characterize the water resources of the BRMA and the greater Big River area, and (2) identify sustainable levels of groundwater use that would minimize effects on water resources. This fact sheet describes the major findings of those studies.

Rhode Island↗

Using citizen scientists to collect oxygen and hydrogen isotope data in southern Nevada

What is Citizen Science? Citizen science programs provide a means for Federal and non-Federal government agencies to make science more engaging, transparent, and accessible by partnering with the public for the purpose of problem solving, data collection, and monitoring. Public volunteers become directly involved in local research, thereby engaging in scientific projects. The public has already been included in existing citizen science programs that cover a broad range of disciplines, such as ecology, hydrology, and tectonics. Citizen science advances research while simultaneously fostering a sense of involvement and interest from the public. Beginning in 2017, the U.S. Geological Survey (USGS), U.S. Forest Service, Bureau of Land Management, U.S. Fish and Wildlife Service, and National Park Service collaborated with private, non-profit partners to inventory, survey, and rehabilitate springs in Clark County, Nevada. The USGS maintains the National Water Information System (NWIS), a publicly available online database of water-resources data for the Nation, and the agency is interested in using citizen science to add geochemical data from springs in southern Nevada. From 2021 to 2023, the USGS directly worked with citizen science partners, including the Springs Stewardship Institute and the Friends of Nevada Wilderness, to collect stable isotope and tritium samples from southern Nevada springs. The citizen science volunteers were provided the training and supplies for proper sample collection by USGS staff. As the citizen science partners traveled and hiked to the remote spring sites to complete spring surveys and perform restoration activities, they collected stable isotope and tritium samples for the USGS. Samples were shipped to national USGS laboratories for analysis, and the results were uploaded to the NWIS database (U.S. Geological Survey, 2024).

Nevada↗

Values and attitudes of National Wildlife Refuge managers and biologists; Report to respondents

The issues affecting natural resource management, the society in which natural resource management occurs, natural resource agency personnel, and the publics they serve have changed in recent decades. Previous studies of Refuge professionals in the U.S. Fish and Wildlife Service (Service) have revealed that employees lack strong commitment to the current organizational structure, were frustrated with the lack of communication within the agency and felt there was a need for strong leadership (PEER 1998, 1999). These results prompted the authors to have further questions about refuge management in the Fish and Wildlife Service. What do employees value about their agency? Is there a difference in values between refuge managers and biologists and if so, what are those differences and what influences those differences? Recently, there has been speculation that changes in society and the demographic makeup of natural resource professionals has caused a paradigm shift for natural resource management (Ballard 2002; Brown and Harris 1992abc, 2000; Maestas 2002). But, there has been little work assessing the values, attitudes or behaviors of natural resource professionals to determine if a paradigm shift is really occurring. Most of the work in the field of values, attitudes, and behaviors has focused on the public and their interaction with environmental management issues; such as, endangered species management (Lybecker et al. 2002; Solomon 1998), human-wildlife conflict (Baker and Fritsch 1997; Chase et al. 1999; Jones and Thomas 1999; Mankin et al. 1999), changes in hunting or trapping regulations (Loker et al. 1998; Manfredo et al. 1999; Whittaker and Torres 1998), or management of public lands (Badalamente et al. 2000). The purpose of this study was to gain a better understanding of the values and attitudes refuge employees have toward natural resources. The goal was to survey National Wildlife Refuge professionals about natural resource management. We surveyed Refuge Managers and Refuge Biologists (n=480) at staffed U.S. National Wildlife Refuges in the contiguous 48 states in the fall of 200 1. We used a modified Dillman design, resulting in a 68% response rate. The objectives of this study were to (1) determine and compare the environmental values of refuge managers and biologists at selected refuges and (2) assess attitudes about various institutional factors (public involvement and planning). Analyses of data revealed that these managers and biologists did not differ substantially in terms of their environmental values. Refuge professionals were supportive of public involvement in planning and management, but hoped to maintain management authority throughout the process. Professionals were skeptical concerning the applicability of long term planning, but were generally supportive of the planning process. Attitudes toward the Service were conflicting: professionals felt that the Service needed to provide better leadership and direction, but that the Refuge System needed to assert its autonomy and independence from the rest of the Service.

Open-File Report↗

Population vulnerability and evacuation challenges in California for the SAFRR tsunami scenario

The SAFRR tsunami scenario models the impacts of a hypothetical yet plausible tsunami associated with a magnitude 9.1 megathrust earthquake east of the Alaska Peninsula. This report summarizes community variations in population vulnerability and potential evacuation challenges to the tsunami. The most significant public-health concern for California coastal communities during a distant-source tsunami is the ability to evacuate people out of potential inundation zones. Fatalities from the SAFRR tsunami scenario could be low if emergency managers can implement an effective evacuation in the time between tsunami generation and arrival, as well as keep people from entering tsunami-prone areas until all-clear messages can be delivered. This will be challenging given the estimated 91,956 residents, 81,277 employees, as well as numerous public venues, dependent-population facilities, community-support businesses, and high-volume beaches that are in the 79 incorporated communities and 17 counties that have land in the scenario tsunami-inundation zone. Although all coastal communities face some level of threat from this scenario, the highest concentrations of people in the scenario tsunami-inundation zone are in Long Beach, San Diego, Newport Beach, Huntington Beach, and San Francisco. Communities also vary in the prevalent categories of populations that are in scenario tsunami-inundation zones, such as residents in Long Beach, employees in San Francisco, tourists at public venues in Santa Cruz, and beach or park visitors in unincorporated Los Angeles County. Certain communities have higher percentages of groups that may need targeted outreach and preparedness training, such as renters, the very young and very old, and individuals with limited English-language skills or no English-language skills at all. Sustained education and targeted evacuation messaging is also important at several high-occupancy public venues in the scenario tsunami-inundation zone (for example, city and county beaches, State or national parks, and amusement parks). Evacuations will be challenging, particularly for certain dependent-care populations, such as patients at hospitals and children at schools and daycare centers. We estimate that approximately 8,678 of the 91,956 residents in the scenario inundation zone are likely to need publicly provided shelters in the short term. Information presented in this report could be used to support emergency managers in their efforts to identify where additional preparedness and outreach activities may be needed to manage risks associated with California tsunamis.

California↗

Water use in Georgia by county for 2010 and water-use trends, 1985–2010

Water use and water withdrawals and returns in 2010 are estimated for each major river basin, principal aquifer, water-planning region, and county in Georgia using data obtained from various Federal and State agencies and local sources. Offstream water use in 2010 is estimated for the categories of public supply, domestic, commercial, industrial, mining, irrigation, livestock, aquaculture, and thermoelectric power. Water-use trends for 1985 to 2010 are also shown. The period between 2007 and 2010 was a challenging time economically and climatologically in Georgia. During that period, the United States was in the midst of a major recession, resulting in decreases in the manufacturing and construction industries and large increases in unemployment. During 2007, 2008, and the latter half of 2010, precipitation in Georgia was substantially below the 30-year norm. According to the 2010 Census of Population and Housing, nearly 9.7 million people lived in Georgia. The water for about 85 percent of that population was provided by public water suppliers. Estimated total water withdrawals from ground-water and surface-water sources were about 4,670 million gallons per day (Mgal/d) in 2010, about a 15-percent reduction from 2005 (5,471 Mgal/d). In 2010, thermoelectric-power facilities (2,046 Mgal/d) and public-supply uses (1,121 Mgal/d) accounted for 68 percent of all water withdrawn in Georgia. Surface-water withdrawals were greatest for thermoelectric-power generation (2,043 Mgal/d), whereas irrigation used the largest amount of groundwater (599 Mgal/d). Surface water provided 78 percent of the 1,121 Mgal/day withdrawn for public supply in 2010. Typically, counties in northern Georgia withdraw a larger percentage of water from surface water than groundwater sources; whereas, counties in the southern part of the State withdraw more water from groundwater sources. Historically, water withdrawals in Georgia were highest in 1980 (6,725 Mgal/d). By 1990, water use had decreased by 20 percent to 5,353 Mgal/d, but increased to 6,487 Mgal/d in 2000. By 2005, water use had decreased to an estimated 5,471 Mgal/d, and declined further to 4,670 Mgal/d in 2010&mdash;a 30-percent decrease since 1980. This decline was evident across all water-use categories, but was greatest for surface-water withdrawals by thermoelectric-power facilities. The estimated total water use per capita in 1985 (total withdrawals for all categories divided by total population) was about 850 gallons per day (gal/d), steadily decreasing to about 798 gal/d in 2000, and decreasing further to 460 gal/d in 2010. Although water use declined among all use categories during that 10-year period, most of the decline in per capita water use was caused by the large decrease in water used for thermoelectric-power generation. Throughout 1985&ndash;2010 water withdrawn for thermoelectric-power generation has constituted the largest volume of offstream water use in Georgia. Total withdrawals for thermoelectric-power generation declined about 37 percent between 2000 and 2010, mostly due to the decommissioning of power plants in the State. Also during this period, several power plants were shut down and re-tooled to use natural gas-powered generators; thus, water withdrawals for cooling were substantially reduced. The decline in water withdrawals and use between 2005 and 2010 can probably be attributed to several factors working together during this period: (1) water conservation laws and policies along with advances in water-conservation technology; (2) the onset of a major recession in 2007; and (3) below average rainfall in 2007, 2008, and the latter half of 2010. Because of these factors, water withdrawn by public suppliers decreased by 4.8 percent (despite a nearly 11-percent increase in population served) and per capita use decreased by 19 percent between 2005 and 2010. About 2,225 Mgal/d of water was returned to Georgia streams and lakes in 2010 under the National Pollutant Discharge Elimination System program administered by the Georgia Environmental Protection Division. This amount is about 48 percent of the total water withdrawn from all sources in 2010. Water returns declined 39 percent between 1995 and 2010, mirroring the decline in water withdrawals during that period. In addition, land applications of treated wastewater increased steadily between 1995 and 2010.

Georgia↗