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At least 1,261 records · Page 70Linked to original sources
USGS2005

Development and analysis of regional curves for streams in the non-urban valley and ridge physiographic province, Maryland, Virginia, and West Virginia

Regression relations for bankfull stream characteristics based on drainage area (often called 'regional curves') are used in natural stream channel design to verify field determinations of bankfull discharge and stream channel characteristics. Bankfull stream characteristics were assessed for stream reaches at 41 streamflow-gaging stations in the Valley and Ridge Physiographic Province in Maryland, Virginia, and West Virginia. Data collected included bankfull cross-sectional geometry, flood plain geometry, and longitudinal profile data. In addition, particle-size distributions of streambed material were determined and data on basin characteristics were compiled for each reach. Regional curves were developed for bankfull cross-sectional area, width, and discharge with R2 values of 0.95, 0.89, 0.87, and 0.91, respectively. Examination of the regional curves residuals indicates that there is more variability in bankfull cross-sectional area, width, and discharge for smaller streams than for larger streams. In contrast, there is more variability for bankfull mean depth for larger streams than for smaller streams. Geographic analysis of regional curve residuals indicated that there were no further subdivisions within the Valley and Ridge Physiographic Province in the three-state study area for which individual sets of regional curves should be developed. In addition, two separate sets of regional curves were developed with data from the 41 sites to examine potential differences in the relations between the southern (n = 9) and central (n = 32) sections of the province. There were differences in slope and intercept between the two bankfull discharge test relations and a difference in intercept for the width test relations at the 95-percent confidence level. However, the results of this analysis were inconclusive and therefore one set of regional curves for the study area is presented in this report. The regional curves were compared to regression models developed from similar data collected in the Pennsylvania and Maryland portions of the province. No statistical difference in the slope or intercept of regression lines of the three data sets was detected for any of the four bankfull parameters at the 95-percent confidence level. Basin characteristics such as percentage of basin forested (percent forested) and percentage of basin underlain by carbonate bedrock (percent carbonate) were analyzed to evaluate variability among regression points. Multivariate regression relations including explanatory terms for percent carbonate and drainage area produced higher R2 values than the regional curves for bankfull cross-sectional area (R2 = 0.95), bankfull width (R2 = 0.92), and bankfull discharge (R2 = 0.93). There was no improvement for the bankfull mean depth relation from adding the additional term. Inclusion of the other basin characteristics in multivariate relations did not improve the regression models. Regression models developed for the 1.5-year discharge for all streamflow-gaging stations with peak discharge data throughout Virginia (n = 486) and throughout the Valley and Ridge Physiographic Province in Virginia (n = 147) were compared to the regional curve relating bankfull discharge to drainage area. A similar trend in decreasing variability with increasing drainage area was observed for the 1.5-year discharge for all stations in Virginia . This indicates that the change in variability observed in the discharge regional curve likely would exist with a larger data set. There was no statistical difference at the 95-percent confidence level between regression relations for the southern section of the province (n = 40) and the central section (n = 107). This finding supports maintaining only one set of regional curves for the study area. Not all of the variability in the regional curves is explained by drainage area alone. Causes of the remaining variability likely vary among study sites. Users of the regional curves developed in this study are cautioned that, because of inherent variability in hydrologic data, a thorough analysis of the fluvial system and the drainage basin is necessary when evaluating the bankfull characteristics of a stream.

Maryland, Virginia, West Virginia↗
USGS2012

Floods of June 2012 in northeastern Minnesota

During June 19–20, 2012, heavy rainfall, as much as 10 inches locally reported, caused severe flooding across northeastern Minnesota. The floods were exacerbated by wet antecedent conditions from a relatively rainy spring, with May 2012 as one of the wettest Mays on record in Duluth. The June 19–20, 2012, rainfall event set new records in Duluth, including greatest 2-day precipitation with 7.25 inches of rain. The heavy rains fell on three major watersheds: the Mississippi Headwaters; the St. Croix, which drains to the Mississippi River; and Western Lake Superior, which includes the St. Louis River and other tributaries to Lake Superior. Widespread flash and river flooding that resulted from the heavy rainfall caused evacuations of residents, and damages to residences, businesses, and infrastructure. In all, nine counties in northeastern Minnesota were declared Federal disaster areas as a result of the flooding. Peak-of-record streamflows were recorded at 13 U.S. Geological Survey streamgages as a result of the heavy rainfall. Flood-peak gage heights, peak streamflows, and annual exceedance probabilities were tabulated for 35 U.S. Geological Survey streamgages. Flood-peak streamflows in June 2012 had annual exceedance probabilities estimated to be less than 0.002 (0.2 percent; recurrence interval greater than 500 years) for five streamgages, and between 0.002 and 0.01 (1 percent; recurrence interval greater than 100 years) for four streamgages. High-water marks were identified and tabulated for the most severely affected communities of Barnum (Moose Horn River), Carlton (Otter Creek), Duluth Heights neighborhood of Duluth (Miller Creek), Fond du Lac neighborhood of Duluth (St. Louis River), Moose Lake (Moose Horn River and Moosehead Lake), and Thomson (Thomson Reservoir outflow near the St. Louis River). Flood-peak inundation maps and water-surface profiles were produced for these six severely affected communities. The inundation maps were constructed in a geographic information system by combining high-water-mark data with high-resolution digital elevation model data. The flood maps and profiles show the extent and depth of flooding through the communities and can be used for flood response and recovery efforts by local, county, State, and Federal agencies.

Minnesota↗
USGS2016

Missouri River Scaphirhynchus albus (pallid sturgeon) effects analysis—Integrative report 2016

The Missouri River Pallid Sturgeon Effects Analysis was designed to carry out three components of an assessment of how Missouri River management has affected, and will affect, population dynamics of endangered Scaphirhynchus albus (pallid sturgeon): (1) collection of reliable scientific information, (2) critical assessment and synthesis of available data and analyses, and (3) analysis of the effects of actions on listed species and their habitats. This report is a synthesis of the three components emphasizing development of lines of evidence relating potential future management actions to pallid sturgeon population dynamics. We address 21 working management hypotheses that emerged from an expert opinion-based filtering process. The ability to quantify linkages from abiotic changes to pallid sturgeon population dynamics is compromised by fundamental information gaps. Although a substantial foundation of pallid sturgeon science has been developed during the past 20 years, our efforts attempt to push beyond that understanding to provide predictions of how future management actions may affect pallid sturgeon responses. For some of the 21 hypotheses, lines of evidence are limited to theoretical deduction, inference from sparse empirical datasets, or expert opinion. Useful simulation models have been developed to predict the effects of management actions on survival of drifting pallid sturgeon free embryos in the Yellowstone and Upper Missouri River complex (hereafter referred to as the “upper river”), and to assess the effects of flow and channel reconfigurations on habitat availability in the Lower Missouri River, tributaries, and Mississippi River downstream of Gavins Point Dam (hereafter referred to as the “lower river”). A population model also has been developed that can be used to assess sensitivity of the population to survival of specific life stages, assess some hypotheses related to stocking decisions, and explore a limited number of management scenarios. Consideration of lines of evidence for each of the 21 hypotheses includes a discussion of how the degree of uncertainty and risk associated with each hypothesis may guide science and implementation strategies. Implementation strategies include full implementation in the field, limited implementations as field-scale experiments, or (in the case of greatest uncertainty) implementation as learning actions, including research and opportunistic experiments or field-based gradient studies. Given the substantive uncertainties associated with pallid sturgeon population dynamics and the need to continually assimilate and assess new information, we proposed that an Effects Analysis-like process should be considered an integral part of ongoing Missouri River adaptive management.

Missouri↗
USGS2022

Potential effects of out-of-basin groundwater transfers on spring discharge, base flow, and groundwater storage pertaining to the Rush Springs aquifer in and near the Caddo Nation of Oklahoma Tribal jurisdictional area, western Oklahoma

The U.S. Geological Survey (USGS), in cooperation with the Caddo Nation of Oklahoma and Bureau of Indian Affairs, assessed four groundwater-withdrawal scenarios and their potential effects on the Rush Springs aquifer in and near the Caddo Nation of Oklahoma Tribal jurisdictional area in western Oklahoma. Increases in industrial and public water supply needs have led to increased development of water resources within the Rush Springs aquifer. As new areas within the aquifer are developed, increased water withdrawals may result in decreases in available groundwater resources and conflicts among water users. For this study, a previously published numerical groundwater-flow model of the Rush Springs aquifer was modified to simulate the potential effects of four groundwater withdrawal scenarios. For the previously published calibrated model, groundwater flow was simulated from 1979 through 2015. In this study, groundwater flow simulations were extended through 2035. The period from 2016 through 2035 is referred to as the “20-year projection.” Four groundwater withdrawal scenarios starting in 2007 and continuing through 2035 were evaluated. Scenario 1 simulated no groundwater withdrawals; scenario 2 simulated no withdrawals allocated for out-of-basin water-use transfers; scenario 3 simulated withdrawals based on reported withdrawals during the 2007–15 simulation period and compounded annual increases in groundwater use during the subsequent 20-year projection; and scenario 4 simulated maximum permitted withdrawals for allocation to out-of-basin water-use transfers. Out-of-basin water transfers were classified as withdrawals that are not returned back to the aquifer. At the springs of interest, changes in water-level altitudes in response to different groundwater withdrawal scenarios were simulated by comparing the results from different model cells. Between 2007 and 2015, scenarios 2–4 yielded similar simulated water-level altitudes in the model cells containing springs of interest, with water-level altitudes decreasing to below the land surface altitude at 13 of the total 25 springs of interest, whereas under scenario 1 there were only two model cells containing springs of interest where the simulated water-level altitudes of a spring decreased to below land surface altitude. For the 20-year projection, water-level altitudes at springs simulated in model cells in scenarios 2–4 decreased to below land surface altitude for 13 of the total 25 model cells containing springs of interest, whereas under scenario 1 there were only two model cells containing springs of interest where the simulated water-level altitudes of a spring decreased to below land surface altitude. The potential effects of groundwater withdrawals were evaluated by comparing changes in groundwater storage between the four scenarios. The 2007–15 groundwater withdrawal scenarios were used to simulate the potential effects of groundwater withdrawal rates on groundwater storage of the Rush Springs aquifer. The simulated groundwater storage change in the Rush Springs aquifer ranged from an increase of 2.8 percent for scenario 1 to an increase of 1.0 percent for scenario 4. Projected 20-year groundwater withdrawal scenarios were used to simulate the potential effects of selected groundwater withdrawal rates on groundwater storage of the Rush Springs aquifer. Simulated groundwater storage changes ranged from a decrease of 0.5 percent for scenario 1 to a decrease of 0.7 percent for scenario 4.

Oklahoma↗
USGS2007

Nitrogen species in soil, sediment, and ground water at a former sewage-treatment wastewater lagoon: Naval Air Station Whidbey Island, Island County, Washington

The potential for contamination of ground water from remnant sewage sludge in re-graded sediments of a deconstructed sewage-treatment lagoon was evaluated. Ground-water levels were measured in temporary drive-point wells, and ground-water samples were collected and analyzed for nutrients and other water-quality characteristics. Composite soil and sediment samples were collected and analyzed for organic carbon and nitrogen species. Multiple lines of evidence, including lack of appreciable organic matter in sediments of the former lagoon, agronomic analysis of nitrogen, the sequestration of nitrogen in the developing soils at the former lagoon, and likely occurrence of peat deposits within the aquifer material, suggest that the potential for substantial additions of nitrogen to ground water beneath the former sewage lagoon resulting from remnant sewage sludge not removed from the former lagoon are small. Concentrations of nitrogen species measured in ground-water samples were small and did not exceed the established U.S. Environmental Protection Agency’s maximum contaminant levels for nitrate (10 milligrams per liter). Concentrations of nitrate in ground-water samples were less than the laboratory reporting limit of 0.06 milligram per liter. Seventy to 90 percent of the total nitrogen present in ground water was in the ammonia form with a maximum concentration of 7.67 milligrams per liter. Concentrations of total nitrogen in ground water beneath the site, which is the sum of all forms of nitrogen including nitrate, nitrite, ammonia, and organic nitrogen, ranged from 1.15 to 8.44 milligrams per liter. Thus, even if all forms of nitrogen measured in ground water were converted to nitrate, the combined mass would be less than the maximum contaminant level. Oxidation-reduction conditions in ground water beneath the former sewage lagoon were reducing. Given the abundant supply of ambient organic carbon in the subsurface and in ground water at the former lagoon, any nitrate that may leach from residual sludge and be transported to ground water with recharge is expected to be quickly denitrified or transformed to nitrite and ammonia under the strongly reducing geochemical conditions that are present. Concentrations of organic carbon, the primary constituent of sewage sludge, in sediments of the former sewage lagoon were less than 1 percent, indicating a near absence of organic matter. The amount of total nitrogen present in the sediments at the former sewage lagoon was only about 25 percent of the amount typically present in developed agricultural soils. The lack of substantial carbon and nitrogen in sediments of the former sewage lagoon indicates that surficial sediments of the former lagoon are essentially devoid of residual sewage sludge. The largest concentration of total nitrogen measured in soil samples from the former sewage lagoon (330 milligrams per kilogram) was used to calculate an estimate of the amount of nitrogen that might be leached from residual sewage sludge by recharge. During the first two years following deconstruction of the former sewage lagoon, the concentration of total nitrogen in recharge leachate might exceed 10 milligrams per liter but the recharge leachate would not likely result in substantial increases in the nitrate concentration in ground water to concentrations greater than the drinking-water maximum contaminant level of 10 milligrams per liter.

Washington↗
USGS2016

Groundwater conditions in Georgia, 2012–14

The U.S. Geological Survey collects groundwater data and conducts studies to monitor hydrologic conditions, better define groundwater resources, and address problems related to water supply, water use, and water quality. In Georgia, water levels were monitored continuously at 181 wells during calendar year 2012, 185 wells during calendar year 2013, and at 171 wells during calendar year 2014. Because of missing data or short periods of record (less than 3 years) for several of these wells, a total of 164 wells are discussed in this report. These wells include 17 in the surficial aquifer system, 18 in the Brunswick aquifer system and equivalent sediments, 68 in the Upper Floridan aquifer, 15 in the Lower Floridan aquifer and underlying units, 10 in the Claiborne aquifer, 1 in the Gordon aquifer, 11 in the Clayton aquifer, 16 in the Cretaceous aquifer system, 2 in Paleozoic-rock aquifers, and 6 in crystalline-rock aquifers. Data from the well network indicate that water levels generally rose during the 2012 through 2014 calendar-year period, with water levels rising in 151 wells, declining in 12, and remained about the same in 1. Water levels declined over the long-term period of record at 94 wells, increased at 60 wells, and remained relatively constant at 10 wells. In addition to continuous water-level data, periodic water-level measurements were collected and used to construct potentiometric-surface maps for the Upper Floridan aquifer in the following areas in Georgia: the Brunswick-Glynn County area during August 2012 and October 2014 and in the Albany-Dougherty County area during November 2012 and November 2014. Periodic water-level measurements were also collected and used to construct potentiometric surface maps for the Cretaceous aquifer system in the Augusta-Richmond County area during August 2012 and July 2014. In general, water levels in these areas were higher during 2014 than during 2012; however, the configuration of the potetiometric surface in each of the areas showed little change. In the Brunswick area, maps showing chloride concentration of water in the Upper Floridan aquifer (constructed using data collected from 25 wells during August 2012 and from 32 wells during October 2014) indicate that chloride concentrations remained above the U.S. Environmental Protection Agency's secondary drinking-water standard in an approximately 2-square-mile area. During calendar years 2012 through 2014, chloride concentrations generally increased in over 90 percent of the wells sampled with a maximum increase of 410 milligrams per liter in a well located in the north-central part of the Brunswick area.

Georgia↗
USGS2012

Occurrence model for volcanogenic beryllium deposits

Current global and domestic mineral resources of beryllium (Be) for industrial uses are dominated by ores produced from deposits of the volcanogenic Be type. Beryllium deposits of this type can form where hydrothermal fluids interact with fluorine and lithophile-element (uranium, thorium, rubidium, lithium, beryllium, cesium, tantalum, rare earth elements, and tin) enriched volcanic rocks that contain a highly reactive lithic component, such as carbonate clasts. Volcanic and hypabyssal high-silica biotite-bearing topaz rhyolite constitutes the most well-recognized igneous suite associated with such Be deposits. The exemplar setting is an extensional tectonic environment, such as that characterized by the Basin and Range Province, where younger topaz-bearing igneous rock sequences overlie older dolomite, quartzite, shale, and limestone sequences. Mined deposits and related mineralized rocks at Spor Mountain, Utah, make up a unique economic deposit of volcanogenic Be having extensive production and proven and probable reserves. Proven reserves in Utah, as reported by the U.S. Geological Survey National Mineral Information Center, total about 15,900 tons of Be that are present in the mineral bertrandite (Be 4 Si 2 O 7 (OH) 2 ). At the type locality for volcanogenic Be, Spor Mountain, the tuffaceous breccias and stratified tuffs that host the Be ore formed as a result of explosive volcanism that brought carbonate and other lithic fragments to the surface through vent structures that cut the underlying dolomitic Paleozoic sedimentary rock sequences. The tuffaceous sediments and lithic clasts are thought to make up phreatomagmatic base surge deposits. Hydrothermal fluids leached Be from volcanic glass in the tuff and redeposited the Be as bertrandite upon reaction of the hydrothermal fluid with carbonate clasts in lithic-rich sections of tuff. The localization of the deposits in tuff above fluorite-mineralized faults in carbonate rocks, together with isotopic evidence for the involvement of magmatic water in an otherwise meteoric water-dominated hydrothermal system, indicate that magmatic volatiles contributed to mineralization. At the type locality, hydrothermal alteration of dolomite clasts formed layered nodules of calcite, opal, fluorite, and bertrandite, the latter occurring finely intergrown with fluorite. Alteration assemblages and elemental enrichments in the tuff and surrounding volcanic rocks include regional diagenetic clays and potassium feldspar and distinctive hydrothermal halos of anomalous fluorine, lithium, molybdenum, niobium, tin, and tantalum, and intense potassium feldspathization with sericite and lithium-smectite in the immediate vicinity of Be ore. Formation of volcanogenic Be deposits is due to the coincidence of multiple factors that include an appropriate Be-bearing source rock, a subjacent pluton that supplied volatiles and heat to drive convection of meteoric groundwater, a depositional site characterized by the intersection of normal faults with permeable tuff below a less permeable cap rock, a fluorine-rich ore fluid that facilitated Be transport (for example, BeF 4 2- complex), and the existence of a chemical trap that caused fluorite and bertrandite to precipitate at the former site of carbonate lithic clasts in the tuff.

Scientific Investigations Report↗
USGS2013

Simulation of salinity intrusion along the Georgia and South Carolina coasts using climate-change scenarios

Potential changes in climate could alter interactions between environmental and societal systems and adversely affect the availability of water resources in many coastal communities. Changes in streamflow patterns in conjunction with sea-level rise may change the salinity-intrusion dynamics of coastal rivers. Several municipal water-supply intakes are located along the Georgia and South Carolina coast that are proximal to the present day saltwater-freshwater interface of tidal rivers. Increases in the extent of salinity intrusion resulting from climate change could threaten the availability of freshwater supplies in the vicinity of these intakes. To effectively manage these supplies, water-resource managers need estimates of potential changes in the frequency, duration, and magnitude of salinity intrusion near their water-supply intakes that may occur as a result of climate change. This study examines potential effects of climate change, including altered streamflow and sea-level rise, on the dynamics of saltwater intrusion near municipal water-supply intakes in two coastal areas. One area consists of the Atlantic Intracoastal Waterway (AIW) and the Waccamaw River near Myrtle Beach along the Grand Strand of the South Carolina Coast, and the second area is on or near the lower Savannah River near Savannah, Georgia. The study evaluated how future sea-level rise and a reduction in streamflows can potentially affect salinity intrusion and threaten municipal water supplies and the biodiversity of freshwater tidal marshes in these two areas. Salinity intrusion occurs as a result of the interaction between three principal forces—streamflow, mean coastal water levels, and tidal range. To analyze and simulate salinity dynamics at critical coastal gaging stations near four municipal water-supply intakes, various data-mining techniques, including artificial neural network (ANN) models, were used to evaluate hourly streamflow, salinity, and coastal water-level data collected over a period exceeding 10 years. The ANN models were trained (calibrated) to learn the specific interactions that cause salinity intrusions, and resulting models were able to accurately simulate historical salinity dynamics in both study areas. Changes in sea level and streamflow quantity and timing can be simulated by the salinity intrusion models to evaluate various climate-change scenarios. The salinity intrusion models for the study areas are deployed in a decision support system to facilitate the use of the models for management decisions by coastal water-resource managers. The report describes the use of the salinity-intrusion models decision support system to evaluate salinity-intrusion dynamics for various climate-change scenarios, including incremental increases in sea level in combination with incremental decreases in streamflow. Operation of municipal water-treatment plants is problematic when the specific-conductance values for source water are greater than 1,000 to 2,000 microsiemens per centimeter (µS/cm). High specific-conductance values contribute to taste problems that require treatment. Data from a gage downstream from a municipal water intake indicate specific conductance exceeded 1,000 µS/cm about 5.4 percent of the time over the 14-year period from August 1995 to August 2008. Simulations of specific conductance at this gaging station that incorporates sea-level rises resulted in a doubling of the exceedances to 11.0 percent for a 1-foot increase and 17.6 percent for a 2-foot increase. The frequency of intrusion of water with specific conductance values of 1,000 µS/cm was less sensitive to incremental reductions in streamflow than to incremental increases in sea level. Simulations of conditions associated with a 10-percent reduction in streamflow, in combination with a 1-foot rise in sea level, increased the percentage of time specific conductance exceeded 1,000 µS/cm at this site from 11.0 to 13.3 percent, and a 20-percent reduction in streamflow increased the percentage of time to 16.6 percent. Precipitation and temperature data from a global circulation model were used, after scale adjustments, as input to a watershed model of the Yadkin-Pee Dee River basin, which flows into the Waccamaw River and Atlantic Intracoastal Waterway study area in South Carolina. The simulated streamflow for historical conditions and projected climate change in the future was used as input for the ANN model in decision support system. Results of simulations incorporating climate-change projections for alterations in streamflow indicate an increase in the frequency of salinity-intrusion events and a shift in the seasonal occurrence of the intrusion events from the summer to the fall.

South Carolina↗
USGS2023

Simulating groundwater flow in the Mississippi Alluvial Plain with a focus on the Mississippi Delta

The Mississippi Alluvial Plain has become one of the most important agricultural regions in the United States but relies heavily on groundwater for irrigation. On average, more than 12 billion gallons are withdrawn daily from the Mississippi River Valley alluvial aquifer. Declining groundwater levels, especially in the Delta region of northwest Mississippi and the Cache and Grand Prairie regions of eastern Arkansas, have led to concerns about future sustainability. The U.S. Geological Survey Mississippi Alluvial Plain Project is focused on quantifying the groundwater system in the alluvial plain and the response of groundwater resources to future development. A key objective of the project is to provide updated groundwater flow models supported by extensive data collection and analyses. MODFLOW 6, PEST++, and several open-source python packages were used to develop a simplified, faster running version of the Mississippi Embayment Regional Aquifer Study model that can provide boundary conditions for local inset models, including the Mississippi Delta model described in this report. An automated workflow was used for model construction, history matching, and development of baseline future climate scenarios. The models incorporate information from a Soil-Water-Balance code simulation of the terrestrial water balance, metering-based estimates of water use from thousands of wells, measured and estimated streamflow and stages, and the largest airborne electromagnetic survey flown to date in the United States. Baseline scenarios for the Mississippi Delta under potential future climates were constructed using recharge, surface runoff and irrigation pumping forcings from a future version of the Soil-Water-Balance model, driven by downscaled temperature and precipitation output from 10 general circulation model simulations, including high and moderate carbon emissions pathways. Results indicate a complex water balance that varies in time and space in terms of the terrestrial recharge, stream leakage, and regional groundwater flow components, which are affected by seasonal forcings, human activity, and alluvial geomorphology. The general circulation model outputs indicate a continued rise in average temperatures but no clear precipitation trend. Increased crop water demand is anticipated from the higher temperatures, resulting in increased irrigation withdrawals to sustain current levels of irrigated agriculture. Simulated drawdowns in groundwater levels at the mid-21st century vary greatly. Under moderate or wet climate scenarios, and in parts of the aquifer that are well connected to surface water, little to no additional drawdown is anticipated. Under dry or warm scenarios, drawdowns of as much as 10 meters or more are possible in parts of the aquifer that are relatively disconnected from surface water. Under dry or warm scenarios, the portion of the Delta with greater than 60 feet of saturated thickness could be reduced from near 100 percent currently (2018) to 80–90 percent by mid-century. Future simulations with the model could include alternative management scenarios to identify options for improving groundwater sustainability. The automated model construction workflows are designed to facilitate regular updating, making this a “living” framework that the Mississippi Department of Environmental Quality and other stakeholders can use for adaptive management going forward.

Arkansas, Louisiana, Mississippi↗
USGS2010

Estimation of groundwater use for a groundwater-flow model of the Lake Michigan Basin and adjacent areas, 1864-2005

The U.S. Geological Survey, at the request of Congress, is assessing the availability and use of the Nation's water resources to help characterize how much water is available now, how water availability is changing, and how much water can be expected to be available in the future. The Great Lakes Basin Pilot project of the U.S. Geological Survey national assessment of water availability and use focused on the Great Lakes Basin and included detailed studies of the processes governing water availability in the Great Lakes Basin. One of these studies included the development of a groundwater-flow model of the Lake Michigan Basin. This report describes the compilation and estimation of the groundwater withdrawals in those areas in Wisconsin, Michigan, Indiana, and Illinois that were needed for the Lake Michigan Basin study groundwater-flow model. These data were aggregated for 12 model time intervals spanning 1864 to 2005 and were summarized by model area, model subregion, category of water use, aquifer system, aquifer type, and hydrogeologic unit model layer. The types and availability of information on groundwater withdrawals vary considerably among states because water-use programs often differ in the types of data collected and in the methods and frequency of data collection. As a consequence, the methods used to estimate and verify the data also vary. Additionally, because of the different sources of data and different terminologies applied for the purposes of this report, the water-use data published in this report may differ from water-use data presented in other reports. These data represent only a partial estimate of groundwater use in each state because estimates were compiled only for areas in Wisconsin, Michigan, Indiana, and Illinois within the Lake Michigan Basin model area. Groundwater-withdrawal data were compiled for both nearfield and farfield model areas in Wisconsin and Illinois, whereas these data were compiled primarily for the nearfield model area in Michigan and Indiana. Overall water use for the selected areas in Wisconsin, Michigan, Indiana, and Illinois was less during early time intervals than during more recent intervals, with large increases beginning around the 1960s. Total estimated groundwater withdrawals for model input range from 18.01 million gallons per day (Mgal/d) for interval 1 (1864-1900) to 1,280.25 Mgal/d for interval 12 (2001-5). Withdrawals for the public-supply category make up the majority of the withdrawals in each of the four states. In Wisconsin and Michigan, the second largest withdrawals are for the irrigation category; in Indiana and Illinois, industrial withdrawals account for the second largest withdrawal amounts. The smallest withdrawals are for miscellaneous uses in Wisconsin and irrigation uses in Indiana and Illinois. Estimated groundwater withdrawals in the Southern Lower Peninsula of Michigan, Northeastern Illinois, and the farfield model area are generally larger than in the other model subregions. Withdrawals in Michigan and Indiana are predominantly from the Quaternary aquifer system, whereas withdrawals in Illinois are predominantly from the Cambrian-Ordovician aquifer systems. Withdrawals in Wisconsin are about equal from the Quaternary and Cambrian-Ordovician aquifer systems. Estimated groundwater withdrawals in Michigan and Indiana are predominantly from the unconfined unconsolidated aquifer type. Withdrawals in Illinois are largely from the deep confined bedrock aquifer type, although they decreased considerably in more recent time intervals. Wisconsin withdrawals are about equal from unconfined unconsolidated and deep confined bedrock aquifer types. Groundwater-withdrawal estimates in Wisconsin were compiled for the 47 easternmost counties within the boundary of the Lake Michigan Basin model, of which 32 counties, though not entirely contained, are at least partly within the Lake Michigan Basin. Overall, 6,457 withdrawal locations were estima

Scientific Investigations Report↗
USGS2010

Temporal change in biological community structure in the Fountain Creek basin, Colorado, 2001-2008

In 2001, the U.S. Geological Survey, in cooperation with Colorado Springs City Engineering, began a study to better understand the relations between environmental characteristics and biological communities in the Fountain Creek basin in order to aide water-resource management and guide future monitoring activities. To accomplish this task, environmental (streamflow, habitat, and water chemistry) and biological (fish and macroinvertebrate) data were collected annually at 24 sites over a 6- or 8-year period (fish, 2003 to 2008; macroinvertebrates, 2001 to 2008). For this report, these data were first analyzed to determine the presence of temporal change in macroinvertebrate and fish community structure among years using nonparametric multivariate statistics. Where temporal change in the biological communities was found, these data were further analyzed using additional nonparametric multivariate techniques to determine which subset of selected streamflow, habitat, or water-chemistry variables best described site-specific changes in community structure relative to a gradient of urbanization. This study identified significant directional patterns of temporal change in macroinvertebrate and fish community structure at 15 of 24 sites in the Fountain Creek basin. At four of these sites, changes in environmental variables were significantly correlated with the concurrent temporal change identified in macroinvertebrate and fish community structure (Monument Creek above Woodmen Road at Colorado Springs, Colo.; Monument Creek at Bijou Street at Colorado Springs, Colo.; Bear Creek near Colorado Springs, Colo.; Fountain Creek at Security, Colo.). Combinations of environmental variables describing directional temporal change in the biota appeared to be site specific as no single variable dominated the results; however, substrate composition variables (percent substrate composition composed of sand, gravel, or cobble) collectively were present in 80 percent of the environmental variable subsets that were significantly correlated with temporal change in the macroinvertebrate and fish community structure. Other important environmental variables related to temporal change in the biological community structure included those describing channel form (streambank height) and streamflow (normalized annual mean daily flow, high flood-pulse count). Site-specific results from this study were derived from a relatively small number of observations (6 or 8 years of data); therefore, additional years of data may reveal other sites with temporal change in biological community structure, or could define stronger and more consistent linkages between environmental variables and observed temporal change. Likewise current variable subsets could become weaker. Nonetheless, there were several sites where temporal change was detected in this study that could not be explained by the available environmental variables studied herein. Modification of current data-collection activities may be necessary to better understand site-specific temporal relations between biological communities and environmental variables.

Scientific Investigations Report↗
USGS2018

Water-quality response to changes in phosphorus loading of the Winnebago Pool Lakes, Wisconsin, with special emphasis on the effects of internal loading in a chain of shallow lakes

The Winnebago Pool is a chain of four shallow lakes (Lake Poygan, Lake Winneconne, Lake Butte des Morts, and Lake Winnebago) that are fed primarily by the Fox and Wolf Rivers, two large agriculturally dominated rivers in Wisconsin, United States. Because the lakes have received extensive phosphorus inputs from their watershed, they have become highly eutrophic with much phosphorus in the water column as well as trapped in their sediments. Each of the four Winnebago Pool lakes has been included on the Wisconsin Department of Natural Resources impaired waters list because of their high total phosphorus concentrations, water-quality use restrictions, and excess algal growth. The study described in this report is part of a Total Maximum Daily Load investigation to determine what actions are needed to improve the water quality (trophic status) of these lakes and thus be able to be removed from the impaired waters list and restore their designated uses. As part of this study, data were collected to describe the existing water quality of the lakes, detailed phosphorus budgets were developed for each of the lakes to describe the different sources of the phosphorus, and two eutrophication models (BATHTUB and Jensen models) were used to determine how much of the phosphorus being input to the lakes needs to be reduced for the lakes to be removed from the impaired waters list and restore their designated uses. In-lake water-quality data indicated that each of the lakes had extensive vertical mixing that resulted in their water quality deteriorating throughout summer. Each of the lakes had mean summer total phosphorus concentrations exceeding 0.088 milligram per liter (mg/L), well above the 0.040 mg/L criterion for the lakes. Detailed phosphorus budgets for the lakes indicated that the primary sources of phosphorus were from their tributaries (for the most upstream lake in the Winnebago Pool–Lake Poygan) or from a combination of input from the upstream lakes and phosphorus release from the bottom sediment when only the summer months were considered (for the other three lakes). Model simulations with the BATHTUB and Jensen models indicated that (1) the lakes should have almost linear response in their total phosphorus concentrations to changes in their phosphorus inputs; (2) phosphorus inputs need to be reduced by about 60 percent to the Upper Pool Lakes and 69–73 percent to Lake Winnebago to reduce their mean summer total phosphorus concentrations to 0.040 mg/L; and (3) if all the anthropogenic phosphorus inputs to the lakes could be eliminated, their best possible mean summer total phosphorus concentrations should decrease to about 0.022–0.028 mg/L in the Upper Pool Lakes and to 0.032–0.033 mg/L in Lake Winnebago. The effects of any reduction in phosphorus loading will take many years (50 to more than 75 years) to be fully realized in lake water quality because of phosphorus release from the lake sediments. The effects of nutrient reductions in the watershed of a chain of lakes, such as the Winnebago Pool, gradually cascades down the chain, which has beneficial and detrimental effects. Any action made in the watershed of upstream lakes to reduce phosphorus inputs should improve the water quality of all downstream lakes; however, the upstream lakes delay the response in the downstream lakes, especially in lakes where internal phosphorus loading is important.

Wisconsin↗
USGS2005

Statistical analysis of long-term hydrologic records for selection of drought-monitoring sites on Long Island, New York

Ground water is the sole source of water supply for more than 3 million people on Long Island, New York. Large-scale ground-water pumpage, sewering systems, and prolonged periods of below-normal precipitation have lowered ground-water levels and decreased stream-discharge in western and central Long Island. No method is currently (2004) available on Long Island that can assess data from the ground-water-monitoring network to enable water managers and suppliers with the ability to give timely warning of severe water-level declines. This report (1) quantifies past drought- and human-induced changes in the ground-water system underlying Long Island by applying statistical and graphical methods to precipitation, stream-discharge, and ground-water-level data from selected monitoring sites; (2) evaluates the relation between water levels in the upper glacial aquifer and those in the underlying Magothy aquifer; (3) defines trends in stream discharge and ground-water levels that might indicate the onset of drought conditions or the effects of excessive pumping; and (4) discusses the long-term records that were used to select sites for a Long Island drought-monitoring network. Long Island’s long-term hydrologic records indicated that the available data provide a basis for development of a drought-monitoring network. The data from 36 stations that were selected as possible drought-monitoring sites—8 precipitation-monitoring stations, 8 streamflow-gaging (discharge) stations, 15 monitoring wells screened in the upper glacial aquifer under water-table (unconfined) conditions, and 5 monitoring wells screened in the underlying Magothy aquifer under semi-confined conditions—indicate that water levels in western parts of Long Island have fallen and risen markedly (more than 15 ft) in response to fluctuations in pumpage, and have declined from the increased use of sanitary- and storm-sewer systems. Water levels in the central and eastern parts, in contrast, remain relatively unaffected compared to the western parts, although the effects of human activity are discernible in the records. The value of each site as a drought-monitoring indicator was assessed through an analysis of trends in the records. Fifty-year annual and monthly data sets were created and combined into three composite-average hydrographs—precipitation, stream discharge, and ground-water levels. Three zones representing the range of human effect on ground-water levels were delineated to help evaluate islandwide hydrologic conditions and to quantify the indices. Data from the three indices can be used to assess current conditions in the ground-water system underlying Long Island and evaluate water-level declines during periods of drought.

Scientific Investigations Report↗
USGS2007

Flood of April 2-4, 2005, Delaware River Main Stem from Port Jervis, New York, to Cinnaminson, New Jersey

Several conditions, including saturated soils, snowmelt, and heavy rains, caused flooding on the Delaware River on April 2-4, 2005. The event occurred 50 years after the historic 1955 Delaware River flood, and only six months after a smaller but equally notable flood on September 18-19, 2004. The Delaware River flooded for a third time in 22 months in June, 2006. The peak flows and elevations of the 2005 flood were similar to those on June 28-29, 2006. The following report describes the April 2-4, 2005, Delaware River flood, and includes the associated precipitation amounts, peak flows and elevations, and flood frequencies. A comparison of historic Delaware River floods also is presented. The appendix of the report contains detailed information for 156 high-water mark elevations obtained on the main stem of the Delaware River from Port Jervis, New York, to Cinnaminson, New Jersey, for the April 2-4, 2005 flood. The April 2005 event originated with frequent precipitation from December 2004 to March 2005 which saturated the soils in the upper Delaware River Basin. The cold winter froze some of the soils and left a snowpack at higher elevations equivalent to as much as 10 inches of water in some areas. Temperatures rose above freezing, and heavy rains averaging 1 to 3 inches on March 27, 2005, melted some of the snow, causing the Delaware River to rise; however, peak elevations were still 2 to 7 feet below flood stage. Another round of rainfall averaging 2-5 inches in the basin on April 2, 2005, melted the remaining snowpack. The combination of snowmelt and runoff from the two storms produced flood conditions along the main stem of the Delaware River. Flood frequencies of flows at selected tributaries to the Delaware River did not exceed the 35-year recurrence intervals. The Delaware River main stem peak-flow recurrence intervals ranged from 40 to 80 years; flows were approximately 20 percent less than those from the peak of record in 1955. Peak elevations exceeded National Weather Service flood stages defined at continuous-record streamflow-gaging stations by 5 to 7 feet, but were on average 3 to 5 feet lower than the peak of record in August 1955. Peak elevations determined at 48 sites along the main stem of the Delaware River defined the flood profile between the gaging stations. The peak elevation in the tide-effected portion of the Delaware (downstream of Trenton, New Jersey), occurred on April 2, 2 days before the riverine peak, as a result of water pushed into the bay by a low-pressure system situated just off the coast. Every county located along the main stem of the Delaware River was declared a Federal disaster area. Property damage estimates in Pennsylvania, New York, and New Jersey exceeded $200 million.

Scientific Investigations Report↗
USGS2008

Estimated Flood-Inundation Mapping for the Upper Blue River, Indian Creek, and Dyke Branch in Kansas City, Missouri, 2006-08

In the interest of improved public safety during flooding, the U.S. Geological Survey, in cooperation with the city of Kansas City, Missouri, completed a flood-inundation study of the Blue River in Kansas City, Missouri, from the U.S. Geological Survey streamflow gage at Kenneth Road to 63rd Street, of Indian Creek from the Kansas-Missouri border to its mouth, and of Dyke Branch from the Kansas-Missouri border to its mouth, to determine the estimated extent of flood inundation at selected flood stages on the Blue River, Indian Creek, and Dyke Branch. The results of this study spatially interpolate information provided by U.S. Geological Survey gages, Kansas City Automated Local Evaluation in Real Time gages, and the National Weather Service flood-peak prediction service that comprise the Blue River flood-alert system and are a valuable tool for public officials and residents to minimize flood deaths and damage in Kansas City. To provide public access to the information presented in this report, a World Wide Web site (http://mo.water.usgs.gov/indep/kelly/blueriver) was created that displays the results of two-dimensional modeling between Hickman Mills Drive and 63rd Street, estimated flood-inundation maps for 13 flood stages, the latest gage heights, and National Weather Service stage forecasts for each forecast location within the study area. The results of a previous study of flood inundation on the Blue River from 63rd Street to the mouth also are available. In addition the full text of this report, all tables and maps are available for download (http://pubs.usgs.gov/sir/2008/5068). Thirteen flood-inundation maps were produced at 2-foot intervals for water-surface elevations from 763.8 to 787.8 feet referenced to the Blue River at the 63rd Street Automated Local Evaluation in Real Time stream gage operated by the city of Kansas City, Missouri. Each map is associated with gages at Kenneth Road, Blue Ridge Boulevard, Kansas City (at Bannister Road), U.S. Highway 71, and 63rd Street on the Blue River, and at 103rd Street on Indian Creek. The National Weather Service issues peak stage forecasts for Blue Ridge Boulevard, Kansas City (at Bannister Road), U.S. Highway 71, and 63rd Street during floods. A two-dimensional depth-averaged flow model simulated flooding within a hydraulically complex, 5.6-mile study reach of the Blue River between Hickman Mills Drive and 63rd Street. Hydraulic simulation of the study reach provided information for the estimated flood-inundation maps and water-velocity magnitude and direction maps. Flood profiles of the upper Blue River between the U.S. Geological Survey streamflow gage at Kenneth Road and Hickman Mills Drive were developed from water-surface elevations calculated using Federal Emergency Management Agency flood-frequency discharges and 2006 stage-discharge ratings at U.S. Geological Survey streamflow gages. Flood profiles between Hickman Mills Drive and 63rd Street were developed from two-dimensional hydraulic modeling conducted for this study. Flood profiles of Indian Creek between the Kansas-Missouri border and the mouth were developed from water-surface elevations calculated using current stage-discharge ratings at the U.S. Geological Survey streamflow gage at 103rd Street, and water-surface slopes derived from Federal Emergency Management Agency flood-frequency stage-discharge relations. Mapped flood water-surface elevations at the mouth of Dyke Branch were set equal to the flood water-surface elevations of Indian Creek at the Dyke Branch mouth for all Indian Creek water-surface elevations; water-surface elevation slopes were derived from Federal Emergency Management Agency flood-frequency stage-discharge relations.

Scientific Investigations Report↗
USGS2014

Potential postwildfire debris-flow hazards: a prewildfire evaluation for the Sandia and Manzano Mountains and surrounding areas, central New Mexico

Wildfire can drastically increase the probability of debris flows, a potentially hazardous and destructive form of mass wasting, in landscapes that have otherwise been stable throughout recent history. Although there is no way to know the exact location, extent, and severity of wildfire, or the subsequent rainfall intensity and duration before it happens, probabilities of fire and debris-flow occurrence for different locations can be estimated with geospatial analysis and modeling efforts. The purpose of this report is to provide information on which watersheds might constitute the most serious, potential, debris-flow hazards in the event of a large-scale wildfire and subsequent rainfall in the Sandia and Manzano Mountains. Potential probabilities and estimated volumes of postwildfire debris flows in the unburned Sandia and Manzano Mountains and surrounding areas were estimated using empirical debris-flow models developed by the U.S. Geological Survey in combination with fire behavior and burn probability models developed by the U.S. Department of Agriculture Forest Service. The locations of the greatest debris-flow hazards correlate with the areas of steepest slopes and simulated crown-fire behavior. The four subbasins with the highest computed debris-flow probabilities (greater than 98 percent) were all in the Manzano Mountains, two flowing east and two flowing west. Volumes in sixteen subbasins were greater than 50,000 square meters and most of these were in the central Manzanos and the western facing slopes of the Sandias. Five subbasins on the west-facing slopes of the Sandia Mountains, four of which have downstream reaches that lead into the outskirts of the City of Albuquerque, are among subbasins in the 98th percentile of integrated relative debris-flow hazard rankings. The bulk of the remaining subbasins in the 98th percentile of integrated relative debris-flow hazard rankings are located along the highest and steepest slopes of the Manzano Mountains. One of the subbasins is several miles upstream from the community of Tajique and another is several miles upstream from the community of Manzano, both on the eastern slopes of the Manzano Mountains. This prewildfire assessment approach is valuable to resource managers because the analysis of the debris-flow threat is made before a wildfire occurs, which facilitates prewildfire management, planning, and mitigation. In northern New Mexico, widespread watershed restoration efforts are being carried out to safeguard vital watersheds against the threat of catastrophic wildfire. This study was initiated to help select ideal locations for the restoration efforts that could have the best return on investment.

New Mexico↗
USGS2006

Continuous water-quality monitoring and regression analysis to estimate constituent concentrations and loads in the Red River of the North, Fargo, North Dakota, 2003-05

This report presents the results of a study by the U.S. Geological Survey, done in cooperation with the Bureau of Reclamation, U.S. Department of the Interior, to estimate water-quality constituent concentrations in the Red River of the North at Fargo, North Dakota. Regression analysis of water-quality data collected in 2003-05 was used to estimate concentrations and loads for alkalinity, dissolved solids, sulfate, chloride, total nitrite plus nitrate, total nitrogen, total phosphorus, and suspended sediment. The explanatory variables examined for regression relation were continuously monitored physical properties of water-streamflow, specific conductance, pH, water temperature, turbidity, and dissolved oxygen. For the conditions observed in 2003-05, streamflow was a significant explanatory variable for all estimated constituents except dissolved solids. pH, water temperature, and dissolved oxygen were not statistically significant explanatory variables for any of the constituents in this study. Specific conductance was a significant explanatory variable for alkalinity, dissolved solids, sulfate, and chloride. Turbidity was a significant explanatory variable for total phosphorus and suspended sediment. For the nutrients, total nitrite plus nitrate, total nitrogen, and total phosphorus, cosine and sine functions of time also were used to explain the seasonality in constituent concentrations. The regression equations were evaluated using common measures of variability, including R2, or the proportion of variability in the estimated constituent explained by the regression equation. R2 values ranged from 0.703 for total nitrogen concentration to 0.990 for dissolved-solids concentration. The regression equations also were evaluated by calculating the median relative percentage difference (RPD) between measured constituent concentration and the constituent concentration estimated by the regression equations. Median RPDs ranged from 1.1 for dissolved solids to 35.2 for total nitrite plus nitrate. Regression equations also were used to estimate daily constituent loads. Load estimates can be used by water-quality managers for comparison of current water-quality conditions to water-quality standards expressed as total maximum daily loads (TMDLs). TMDLs are a measure of the maximum amount of chemical constituents that a water body can receive and still meet established water-quality standards. The peak loads generally occurred in June and July when streamflow also peaked.

North Dakota↗
USGS2007

Water-resource trends and comparisons between partial-development and October 2006 hydrologic conditions, Wood River Valley, south-central Idaho

This report analyzes trends in ground-water and surface-water data, documents 2006 hydrologic conditions, and compares 2006 and historic ground-water data of the Wood River Valley of south-central Idaho. The Wood River Valley extends from Galena Summit southward to the Timmerman Hills. It is comprised of a single unconfined aquifer and an underlying confined aquifer present south of Baseline Road in the southern part of the study area. Streams are well-connected to the shallow unconfined aquifer. Because the entire population of the area depends on ground water for domestic supply, either from domestic or municipal-supply wells, rapid population growth since the 1970s has raised concerns about the continued availability of ground and surface water to support existing uses and streamflow. To help address these concerns, this report evaluates ground- and surface-water conditions in the area before and during the population growth that started in the 1970s. Mean annual water levels in three wells (two completed in the unconfined aquifer and one in the confined aquifer) with more than 50 years of semi-annual measurements showed statistically significant declining trends. Mean annual and monthly streamflow trends were analyzed for three gaging stations in the Wood River Valley. The Big Wood River at Hailey gaging station (13139500) showed a statistically significant trend of a 25-percent increase in mean monthly base flow for March over the 90-year period of record, possibly because of earlier snowpack runoff. Both the 7-day and 30-day low-flow analyses for the Big Wood River near Bellevue gaging station (13141000) show a mean decrease of approximately 15 cubic feet per second since the 1940s, and mean monthly discharge showed statistically significant decreasing trends for December, January, and February. The Silver Creek at Sportsman Access near Picabo gaging station (13150430) also showed statistically significant decreasing trends in annual and mean monthly discharge for July through February and April from 1975 to 2005. Comparisons of partial-development (ground-water conditions from 1952 to 1986) and 2006 ground-water resources in the Wood River Valley using a geographic information system indicate that most ground-water levels for the unconfined aquifer in the study area are either stable or declining. Declines are predominant in the southern part of the study area south of Hailey, and some areas exceed what is expected of natural fluctuations in ground-water levels. Some ground-water levels rose in the northern part of the study area; however, these increases are approximated due to a lack of water-level data in the area. Ground-water level declines in the confined aquifer exceed the range of expected natural fluctuations in large areas of the confined aquifer in the southern part of the study area in the Bellevue fan. However, the results in this area are approximated due to limited available water-level data.

Idaho↗