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Water-resources-related information for the Milwaukee Metropolitan Sewerage District planning area, Wisconsin, 1970-2002

The Milwaukee Metropolitan Sewerage District (MMSD) Corridor Study is a three-phase project designed to improve the understanding of water resources in the stream corridors of the MMSD planning area by initially compiling existing data and using the compiled information to develop 3-year baseline and long-term monitoring plans. This report is one of the products of Phase I of the Corridor Study. A literature review of surface-water-quality, surface water- quantity, and ecology studies conducted from 1970 through 2001 was completed and is summarized in this report. An inventory of Geographic Information System spatial coverages available for the MMSD planning area has been assembled. A database of water, sediment, and tissue (fish, shellfish, and others) chemistry, macroinvertebrates, fish, algae, habitat, geomorphic, and other physical and ecological data was compiled from data sets from MMSD, U.S. Geological Survey, Wisconsin Department of Natural Resources, and the U.S. Environmental Protection Agency. More than 2.7 million results are available in the MMSD Corridor Study database and the compilation of multiple datasets allows for retrieving data from a central database rather than from each of the source datasets. Data for 1970 through 2002 were collected for the 420-square-mile planning area by various agencies using different field data-collection and laboratory analysis methods. Chemical constituents and ecological components that are important to an urban setting and well represented in the database were selected for further investigation. Each constituent or component is described in this report with some or all of the following: a text summary, map of sampling locations, and in some cases median concentrations, statistical distributions of concentrations by subwatershed, table of summary statistics by subwatershed, and graphs of temporal and (or) seasonal trends. Physical data presented in the report include streamflow, stream stage, and precipitation data. Chemical indicators of water quality presented in the report include field measurements and miscellaneous constituents (pH, alkalinity, specific conductance, hardness, dissolved oxygen, biochemical oxygen demand, and chloride), sediment (total suspended solids and suspended sediment), nutrients (total nitrogen, nitrate, Kjeldahl nitrogen, total phosphorus, and dissolved phosphorus), trace elements (cadmium, mercury, copper, lead, arsenic, chromium, nickel, and zinc), pesticides (historically used pesticides and pesticides still in use), and polychlorinated biphenyls. Ecological indicators of water quality discussed in the report include community surveys of macroinvertebrates and fish, chlorophyll a concentrations, habitat assessments and channel-measurement data, and fecal coliform and E. coli bacterial counts. In addition to the compilation of the database, a major purpose of this investigation was to identify additional sampling that should be conducted under the baseline monitoring phase, which will be the second phase of the Corridor Study. Additional sampling may include: • Some subwatersheds, such as those in the headwaters. • Emerging contaminants such as pharmaceuticals and personal care products (PPCPs), human hormones, organic wastewater contaminants, and other constituents that result from human activity. • E. coli, which can serve as an indicator of health risk to swimmers and other recreational water users. • Pesticides in all media. • PCBs. • Trace elements in water, bed sediment, and tissues (fish, shellfish, and others). • Samples during winter months or during early snowmelt episodes to address constituents such as chloride and some nutrients that have seasonal variability and that may be affected by factors such as road deicing during the winter. • Samples for macroinvertebrate and fish-community data and habitat assessments. • Physical data such as stream-channel cross-section profiles, bridge-scour assessments, flood-plain maps, structures, and shoreline conditions.

Wisconsin

Application of the Stream Salmonid Simulator (S3) model to assess fall Chinook salmon (Oncorhynchus tshawytscha) production in the American River, California

Executive Summary Anadromous fish returning to the lower American River are restricted to 36 kilometers of free-flowing river between Nimbus Dam and American River’s confluence with the Sacramento River, California. Salmon in the American River provide an important freshwater recreational fishery. However, annual salmon production in the American River in recent years has been low relative to the mid-1990s (Surface Water Resources, Inc., 2001). To investigate the low production of fall-run Chinook salmon ( Oncorhynchus tshawytscha ), the Bureau of Reclamation requested that the U.S. Geological Survey apply the Stream Salmonid Simulator (S3) model to the population of fall-run Chinook salmon on the American River. The American River was chosen among seven candidate Sacramento Basin rivers for S3 application. The American River was selected because of its management and public interest, recently low anadromous fish production, and rich time series of key demographic data needed for S3 application. Data that were not available, however, were empirical estimates on juvenile salmon habitat suitability in the American River. Therefore, a large component of applying S3 to the American River was devoted to the estimation of juvenile salmon habitat suitability and capacity. This entailed snorkeling the lower American River for 3 weeks in March 2021 during the early out-migration period for juvenile Chinook salmon. These efforts were fruitful and showed that the typically small fish (<55 millimeters) in the American River preferred much shallower depths than predicted by habitat suitability criteria derived from the literature for this population. Having empirical estimates on juvenile salmon in the American River provided a solid foundation from which to simulate the population using the S3 model. The S3 model is a spatially explicit population model that runs on a daily time step to simulate redd superimposition, egg maturation, fry emergence and the subsequent growth, survival, and emigration of juvenile Chinook salmon from the river. The key features of this model relevant to this report include (1) a temperature-dependent bioenergetics model driving daily growth rates; (2) density-dependent dynamics that are influenced by the effect of flow on suitable habitat area; and (3) within-year habitat, river flow, and water temperature effects specific to spawning, egg incubation, and fry, parr, and smolt life stages. We used estimates of spawning escapement and geo-referenced redd locations to quantify the spatial and temporal distribution of female spawners for brood years 2014–19. These estimates of female spawners initiate the simulation of each year’s juvenile salmon emergence and emigration over a spatial domain extending from Nimbus Dam to the river’s confluence with the Sacramento River. Using weekly estimates of juvenile salmon abundance and size (fork length) that passed the Watt Avenue fish trap (river kilometer 14.7), we calibrated the S3 model by estimating three key demographic parameters for each year, y : (1) S y , the average daily survival probability, (2) M 0y , the intercept for density-dependence in movement, representing the average daily probability of remaining in a habitat at zero abundance, and (3) C y , the average daily proportion of maximum consumption. These parameters were obtained by minimizing the Mallow’s distance (Lupu and others, 2017) between distributions of weekly abundances and sizes of fish at the traps and weekly simulated abundances and sizes (by S3). Investigation of model fit showed excellent agreement between simulated annual abundances and the abundance of fish passing the fish trap. However, when we compared weekly abundances at the fish trap, S3 under-predicted peaks and over-predicted troughs in the time series of weekly abundances at the fish trap. Thus, some unknown within-year effects have yet to be identified and incorporated in the S3 model. Identifying these important effects and incorporating them in the S3 model would help explain the lack of fit between estimated and simulated weekly abundances. We estimated parameters for 6 years that included a wide range of female spawner abundances (3,057–10,753) and water year types (Critical–Wet). We contrast our estimated parameters to the corresponding number of female spawners and the water year type for the Sacramento Valley. By happenstance, years having higher annual spawner abundances concurred with Critical to Dry water year types. Estimates of survival trended lower with higher spawner abundances and Critical to Dry conditions. In contrast, the extremely wet water year of 2017 had the lowest M 0y , suggesting less density-dependence in fish movement, and the lowest C y , suggesting lower average consumption in this year. When this high-flow year was excluded, a trend towards higher probabilities of fish remaining in a habitat at low abundance and lower proportions of maximum consumption was apparent from Critical to Wet conditions, but only 5 years of data were included. Except for 2017, daily proportions of maximum consumption were relatively high ( C y > 0.83), suggesting that fish were feeding at reasonably high proportions relative to the expected maximum consumption as defined by the “Wisconsin” bioenergetics model (Stewart and Ibarra, 1991). Survival estimates from fry emergence to outmigration at the Sacramento River confluence were generally low when integrated over time. The highest daily survival probability was S y = 0.93 in 2019, or 50 percent total mortality after 10 days. In contrast, our lowest daily survival probability was S y = 0.74 in 2015, or 95 percent total mortality after 10 days. Consequently, even our highest estimated daily survival probability might be considered low. This is especially true given that S y was estimated over a relatively short distance (<14.7 kilometers) from emergence to the Watt Avenue fish trap. Several factors, including our assumed and relatively high daily egg survival rate of 0.9975, could influence juvenile survival estimates. For example, an egg survival rate of 0.9975 results in 3-percent total mortality after 10 days. Egg mortality estimates used in S3 calibration were approximated from egg survivorship studies in the Yakima River, Washington (Johnson and others, 2012), and remains one of the greater uncertainties in S3 when estimating survival across life stages. By including bona fide estimates of egg survival in S3 simulations, the validity of the S3’s current daily egg survival rate could be assessed specifically for the American River. Tagging studies also could provide S3 with direct estimates of juvenile survival and movement; survival during egg incubation then could be estimated indirectly via model fitting.

California

General summary of effects of the drought in the Southwest: Chapter H in Drought in the Southwest, 1942-56

This final chapter of Prof. Paper 372 summarizes the results of a comprehensive study of drought in the Southwest, as reported in greater detail in chapters A-G. Chapter A presents some of the published and recorded conclusions concerning the basic meteorological factors that influence the patterns of precipitation in the Southwest, and describes the characteristics of the drought of 1942-56 as indicated by meteorologic records. Chapter B is a general discussion of the effects of that drought as shown by hydrologic data. Subsequent chapters (C-G) provide more detailed evaluations of the effects of drought in individual river basins and specific localities. The effects of drought are discriminated from water shortages due to other causes wherever possible. For this summary, the hydrologic units in the Southwest are classified according to type, and examples of each type are cited, but no attempt is made to summarize the effects of drought in every hydrologic unit in the Southwest, as was described in preceding parts of this report. The comprehensive study of drought has required analysis of the longest records available concerning all aspects of the water resources, with special attention to the 1942-56 period to ascertain similarities with earlier drought periods and contrasts with periods of greater precipitation. Despite the intended emphasis on drought, the studies have been almost as broad in scope as general studies of interrelations of the hydrologic cycle.

Southwestern United States

Low-flow characteristics and profiles for the Rocky River in the Yadkin-Pee Dee River basin, North Carolina, through 2002

An understanding of the magnitude and frequency of low-flow discharges is an important part of protecting surface-water resources and planning for municipal and industrial economic expansion. Low-flow characteristics are summarized for 12 continuous-record gaging stations and 44 partial-record measuring sites in the Rocky River basin in North Carolina. Records of discharge collected through the 2002 water year at continuous-record gaging stations and through the 2001 water year at partial-record measuring sites were used. Flow characteristics included in the summary are (1) average annual unit flow; (2) 7Q10 low-flow discharge, the minimum average discharge for a 7-consecutive-day period occurring, on average, once in 10 years; (3) 30Q2 low-flow discharge; (4) W7Q10 low-flow discharge, which is similar to 7Q10 discharge but is based only on flow during the winter months of November through March; and (5) 7Q2 low-flow discharge. The Rocky River basin drains 1,413 square miles (mi 2 ) of the southern Piedmont Province in North Carolina. The Rocky River is about 91 miles long and merges with the Yadkin River in eastern Stanly County to form the Pee Dee River, which discharges into the Atlantic Ocean in South Carolina. Low-flow characteristics compiled for selected sites in the Rocky River basin indicated that the potential for sustained base flows in the upper half of the basin is relatively higher than for streams in the lower half of the basin. The upper half of the basin is underlain by the Charlotte Belt, where streams have been identified as having moderate potentials for sustained base flows. In the lower half of the basin, many streams were noted as having little to no potential for sustained base flows. Much of the decrease in base-flow potential is attributed to the underlying rock types of the Carolina Slate Belt. Of the 19 sites in the basin having minimal (defined as less than 0.05 cubic foot per second) or zero 7Q10 discharges, 18 sites are located in the lower half of the basin underlain by the Carolina Slate Belt. Assessment of these 18 sites indicates that streams that have drainage areas less than about 25 square miles are likely to have minimal or zero 7Q10 discharges. No drainage-area threshold for minimal or zero 7Q10 discharges was identified for the upper half of the basin, which is underlain by the Charlotte Belt. Tributaries to the Rocky River include the West Branch Rocky River (22.8 mi 2 ), Clarke Creek (28.2 mi 2 ), Mallard Creek (41.2 mi 2 ), Coddle Creek (78.8 mi 2 ), Reedy Creek (43.0 mi 2 ), Irish Buffalo/Coldwater Creeks (110 mi 2 ), Dutch Buffalo Creek (99 mi 2 ), Long Creek (200 mi 2 ), Richardson Creek (234 mi 2 ), and Lanes Creek (135 mi 2 ). In the 20-mile reach upstream from the mouth (about 22 percent of the river length), the drainage area increases by 648 mi 2 , or about 46 percent of the total drainage area as a result of the confluences with Long Creek, Richardson Creek, and Lanes Creek. Low-flow discharge profiles for the Rocky River include 7Q10, 30Q2, W7Q10, and 7Q2 discharges in a continuous profile with contributions from major tributaries included. At the gaging stations above Irish Buffalo Creek and near Stanfield, the 7Q10 discharges are 25.2 and 42.3 cubic feet per second, corresponding to 0.09 and 0.07 cubic feet per second per square mile, respectively. At the gaging station near Norwood, the 7Q10 discharge is 45.8 cubic feet per second, equivalent to 0.03 cubic foot per second per square mile. Low-flow discharge profiles reflect the presence of several major flow diversions in the reaches upstream from Stanfield and an apparent losing reach between the continuous-record gaging stations near Stanfield and Norwood, North Carolina.

North Carolina

Synopsis of geologic and hydrologic results: Chapter A in Geological Survey research 1961

The Geological Survey is engaged in many different kinds of investigations in the fields of geology and hydrology. These investigations may be grouped into several broad, inter-related categories as follows: (a) Economic geology, including engineering geology (b) Regional geologic mapping, including detailed mapping and stratigraphic studies (c) Resource and topical studies (d) Ground-water studies (e) Surface-water studies (f) Quality-of-water studies (g) Field and laboratory research on geologic and hydrologic processes and principles. The Geological Survey also carries on investigations in its fields of competence for other Federal agencies that do not have the required specialized staffs or scientific facilities. Nearly all the Geological Survey's activities yield new data and principles of value in the development or application of the geologic and hydrologic sciences. The purpose of this report, which consists of 4 chapters, is to present as promptly as possible findings that have come to the fore during the fiscal year 1961 the 12 months ending June 30, 1961. The present volume, chapter A, is a synopsis of the highlights of recent findings of scientific and economic interest. Some of these findings have been published or placed on open file during the year; some are presented in chapters B, C, and D; still others have not been published previously. Only part of the scientific and economic results developed during the year can be presented in this synopsis. Readers who wish more complete or more detailed information should consult the bibliography of reports beginning on page A-156 of this volume, and the collection of short articles presented in the companion chapters as follows: Prof. Paper 424-B Articles 1 to 146 Prof. Paper 424-C Articles 147 to 292 Prof. Paper 424-D Articles 293 to 435 A list of investigations in progress in the Geologic and Water Resources Divisions with the names and addresses of the project leaders is given on pages A-110 to A-155 for those interested in work in progress in various areas or on special topics. During the fiscal year 1961, the services of the Geologic and Water Resources Divisions were utilized, or supported financially in part, by the many Federal and State agencies listed on pages A-106 to A-109. The Geological Survey has also cooperated from time to time with other agencies, and some of the work described in these chapters stems from work of previous years in cooperation with agencies not shown on the list. All cooperating agencies are identified where appropriate in the individual short articles in chapters B, C, and D, and they are mentioned in connection with some of the larger programs summarized in chapter A; because of space limitations, however, their contributions are mentioned in many of the short summary paragraphs contained in chapter A.

Professional Paper

Geographic, geologic, and hydrologic summaries of intermontane basins of the northern Rocky Mountains, Montana

This report combines a literature review with new information to provide summaries of the geography, geology, and hydrology of each of 32 intermontane basins in western Montana. The summary of each intermontane basin includes concise descriptions of topography, areal extent, altitude, climate, 1990 population, land and water use, geology, surface water, aquifer hydraulic characteristics, ground-water flow, and ground-water quality. If present, geothermal features are described. Average annual and monthly temperature and precipitation are reported from one National Weather Service station in each basin. Streamflow data, including the drainage area, period of record, and average, minimum, and maximum historical streamflow, are reported for all active and discontinued USGS streamflow-gaging stations in each basin. Monitoring-well data, including the well depth, aquifer, period of record, and minimum and maximum historical water levels, are reported for all long-term USGS monitoring wells in each basin. Brief descriptions of geologic, geophysical, and potentiometric- surface maps available for each basin also are included. The summary for each basin also includes a bibliography of hydrogeologic literature. When used alone or in conjunction with regional RASA reports, this report provides a practical starting point for site-specific hydrogeologic investigations.

Water-Resources Investigations Report

Summary of hydrologic conditions in Kansas, 2013 water year

The U.S. Geological Survey (USGS) Kansas Water Science Center (KSWSC), in cooperation with local, State, and other Federal agencies, maintains a long-term network of hydrologic monitoring gages in the State of Kansas. These include 195 real-time streamflow-gaging stations (herein gages) and 12 real-time reservoir-level monitoring stations. These data and associated analysis, accumulated for many years, provide a unique overview of hydrologic conditions and help improve our understanding of our water resources.

Kansas

Water-resources investigations of the U.S. Geological Survey in Colorado; fiscal year 1980

Water-resources data-collection activities for October 1, 1979, through September 30, 1980, are summarized for Colorado and bordering States. Fifty-four interpretive hydrologic investigations include: 9 statewide investigations, 6 regional investigations, 11 investigations in the Missouri River basin, 7 investigations in the Arkansas River basin, 3 investigations in the Rio Grande basin, 16 investigations in the Colorado River basin, and 2 multistate investigations. The summaries of the investigations consist of a map showing the location of the areas of investigations and a brief description of the investigation's purpose, objective, approach, progress, and plans.

Colorado

National Research Program of the Water Resources Division, U.S. Geological Survey: Fiscal Year 1988

The National Research Program (NRP) of the US Geological Survey 's Water Resources Division (WRD) had its beginnings in the late 1950 's when ' core research ' was added as a line item to the Congressional budget. Since that time, the NRP has grown to encompass a broad spectrum of scientific investigations. The sciences of hydrology, mathematics, chemistry, physics, ecology, biology, geology, and engineering are used to gain a fundamental understanding of the processes that affect the availability, movement, and quality of the Nation 's water resources. The NRP is located principally in Reston, VA, Denver, CO, and Menlo Park , CA. The NRP is subdivided into six disciplines as follows: (1) Ecology; (2) Geomorphology and Sediment Transport; (3) Groundwater Chemistry; (4) Groundwater Hydrology; (5) Surface Water Chemistry; and (6) Surface Water Hydrology. The report provides current information about the NRP on an annual basis. Organized by the six research disciplines, the volume contains a summary of the problem, objective, approach, and progress for each project that was active during fiscal year 1988.

Open-File Report

Flood of July 21, 1975 in Mercer County, New Jersey

Intense rainfall during the evening of July 20 and early morning hours of July 21, 1975 caused flooding of unprecedented magnitude in highly urbanized Mercer County, New Jersey. Over 6 inches (152 millimetres) of rainfall was recorded during a 10-hour period at Trenton, the capital of New Jersey. No lives were lost but damages to highways and bridges, to industrial, business, and residential buildings, to farmlands and crops, and to water supply systems were severe. This report illustrates the magnitude of the flood and provides hydrologic data needed for planning and design to control or lessen damages from future floods. It includes discussions of the antecedent conditions and meteorological aspects of the storm; a description of the flood and comparison to previous floods; a summary of flood stages and discharges; a discussion of flood frequency; and photomosaics which show inundated areas. More than 200 high-water marks are described as to location and elevation above mean sea level.

New Jersey

Estimating soil moisture, actual evapotranspiration, climatic water deficit, and groundwater recharge during periods of drought for current and future climate conditions in Hawaiʻi

Mid- and end-of-century climate projections for the Hawaiian Islands indicate that rainfall is projected to decrease across large areas. In areas affected by drought or where the future climate becomes drier, reduced groundwater recharge can affect freshwater availability. Reduced rainfall can also reduce soil moisture, which can increase the risk of wildfire. Cloud-water interception, or fog drip, is the process by which cloud-water droplets are captured on the leaves and branches of plants with some of the captured cloud water subsequently dripping to the ground. Studies in Hawaiʻi indicate that fog drip can contribute substantially to total precipitation and may have the potential to lessen the negative effects of drought or a drying climate on freshwater availability and wildfire risk. Wildfire danger assessments in the continental United States have used estimates of soil moisture, evapotranspiration, and climatic water deficit (that is, the evaporative demand that exceeds available water) to improve the identification of areas at risk for wildfires. In this study, water-budget models developed for the islands of Kauaʻi, Oʻahu, Molokaʻi, Maui, and Hawaiʻi were used to quantify the effects of severe drought, future climate conditions, and reducing or eliminating fog drip on groundwater recharge, soil moisture, evapotranspiration, and climatic water deficit. Island-wide summaries of groundwater recharge, soil moisture, evapotranspiration, and climatic water deficit were developed to (1) illustrate changes between recent, drought, and future climate conditions, (2) illustrate the effects of reducing or eliminating fog drip for recent, drought, and future climate conditions, and (3) highlight areas of increased potential risk for wildfire during drought and future climate conditions. The results of these analyses can be used by natural resource managers in Hawaiʻi.

Hawaii

Groundwater level and nitrate concentration trends on Mountain Home Air Force Base, southwestern Idaho

Mountain Home Air Force Base in southwestern Idaho draws most of its drinking water from the regional aquifer. The base is located within the State of Idaho's Mountain Home Groundwater Management Area and is adjacent to the State's Cinder Cone Butte Critical Groundwater Area. Both areas were established by the Idaho Department of Water Resources in the early 1980s because of declining water levels in the regional aquifer. The base also is listed by the Idaho Department of Environmental Quality as a nitrate priority area. The U.S. Geological Survey, in cooperation with the U.S. Air Force, began monitoring wells on the base in 1985, and currently monitors 25 wells for water levels and 17 wells for water quality, primarily nutrients. This report provides a summary of water-level and nitrate concentration data collected primarily between 2001 and 2013 and examines trends in those data. A Regional Kendall Test was run to combine results from all wells to determine an overall regional trend in water level. Groundwater levels declined at an average rate of about 1.08 feet per year. Nitrate concentration trends show that 3 wells (18 percent) are increasing in nitrate concentration trend, 3 wells (18 percent) show a decreasing nitrate concentration trend, and 11 wells (64 percent) show no nitrate concentration trend. Six wells (35 percent) currently exceed the U.S. Environmental Protection Agency's maximum contaminant limit of 10 milligrams per liter for nitrate (nitrite plus nitrate, measured as nitrogen).

Idaho

Review of Available Water-Quality Data for the Southern Colorado Plateau Network and Characterization of Water Quality in Five Selected Park Units in Arizona, Colorado, New Mexico, and Utah, 1925 to 2004

Historical water-quality data in the National Park Service Southern Colorado Plateau Network have been collected irregularly and with little followup interpretation, restricting the value of the data. To help address these issues, to inform future water-quality monitoring planning efforts, and to address relevant National Park Service Inventory and Monitoring Program objectives, the U.S. Geological Survey, in cooperation with the National Park Service, compiled, reviewed, and summarized available historical water-quality data for 19 park units in the Southern Colorado Plateau Network. The data are described in terms of availability by major water-quality classes, park unit, site type, and selected identified water sources. The report also describes the geology, water resources, water-quality issues, data gaps, and water-quality standard exceedances identified in five of the park units determined to be of high priority. The five park units are Bandelier National Monument in New Mexico, Canyon de Chelly National Monument in Arizona, Chaco Culture National Historical Park in New Mexico, Glen Canyon National Recreation Area in Arizona and Utah, and Mesa Verde National Park in Colorado. Statistical summaries of water-quality characteristics are presented and considerations for future water-quality monitoring are provided for these five park units.

Scientific Investigations Report

Hydrogeology of the Pine Ridge Indian Reservation, South Dakota

An investigation of the geology and ground-water resources of the Pine Ridge Indian Reservation, South Dakota, was made at the request of the Bureau of Indian Affairs as part of the U.S. Department of the Interior's program for the development of the Missouri River basin. The area of investigation (about 3,930 square miles) includes all the land within the original boundaries of the Reservation, except for that part of Bennett County south of the U.S. Highway 18, where there are only small tracts of Indian land. Emphasis in the study was placed on mapping major rock units and on determining their potential as sources of water for domestic and stock use. The geologic map on sheet 1 shows the areal extent of the major rock units, and a summary of the stratigraphy and physical characteristics of the exposed geologic formations is given in the table on this sheet. The writers appreciate the cooperation of the personnel of the South Dakota State Geological Survey, who provided most of the well data for Bennett County, information about the stratigraphy and geology of selected areas, and copies of published and unpublished geologic maps. (See map showing areas mapped prior to this investigation.) Also, they appreciate the cooperation of ranch owners and tenants, who permitted access to their lands, and the personnel of the Bureau of Indian affairs, who supplied soils mps and other data. Data on which this report is based, including logs of wells and test holes, chemical analyses of water and records of wells and springs, have been summarized by the authors in a basic-data report published jointly by the South Dakota Geological Survey and South Dakota Water Resources Commission (Water Resources Report 4, Basic hydrogeologic data - Pine Ridge Indian Reservation, South Dakota). A selected bibliography of reports pertaining to the geology of the area has been included in the basic-data report. This atlas will be more useful if studied in conjunction with a copy of the basic-data report.

South Dakota

Summary of exploration geochemical and mineralogical studies at the giant Pebble porphyry Cu-Au-Mo deposit, Alaska: Implications for exploration under cover

Exploration geochemical and mineralogical studies by the U.S. Geological Survey at the Pebble porphyry Cu-Au-Mo deposit were designed to (1) determine whether the concealed deposit can be detected with surface samples, (2) better understand the processes of metal migration from the deposit to the surface, and (3) test existing methods for assessing concealed mineral resources and/or develop new ones. Surface water (ponds, streams, and springs), pond and stream sediment, soils subjected to various leaching techniques, and glacial till samples were collected. The tilted nature of the undisturbed orebody, varying depth of cover, and later glacial processes, strongly influence the geochemical responses and processes active on the various sample media. The multimedia approach aids in identifying possible processes that caused the significant geochemical variations within and among the various media. These processes include the following: In the Pebble West zone, thin cover and local exposure of the orebody have facilitated the oxidation of pyrite and other sulfides, and associated ferrous-ferric iron reactions, resulting in the local natural acidification of ponds observed in the West zone, and in associated metal anomalies in waters, sediments, and soils. In contrast, the East zone is concealed by both glacial deposits and underlying thick cover rocks, which precludes the oxidation of sulfides in the underlying orebody. Low-level geochemical anomalies in circumneutral spring and pond waters from the East zone are discernible only by using high resolution-inductively coupled plasma-mass spectrometry with lower limits of determination two and perhaps three orders of magnitude lower than traditional methods. A variety of partial leaches of soils over the East zone reveal geochemical anomalies in a similar suite of elements that may be related to upwelling waters from depth along graben-bounding faults. The indicator minerals gold, jarosite, and andradite in till reveal a displaced mineralogical anomaly to the west and south of the Pebble orebody, as ore-related minerals were scraped from the orebody and deposited in till downice of the deposit. Geochemical anomalies in pond water and sediment over the displaced till are attributed to the ore-related minerals in till. This orientation study demonstrates the strong control of local geologic and geochemical settings on the effectiveness of different traditional and newer reconnaissance geochemical exploration techniques and thus has important implications for exploration.

Alaska

Lake belt study area: High-resolution seismic-reflection survey, Miami-Dade County Florida

Executive Summary The Northwest Dade County Freshwater Lake Plan Area (commonly referred to as the Lake Belt Area) is vital to the future planning and development of southeastern Florida. This area is located within one of the most environmentally sensitive parts of the state – the eastern borders of the Everglades National Park (ENP). The Lake Belt Area and Water Conservation Area BB (WCA BB) provide half of the limestone mining resources used in the state every year. Starting in the mid-1800s canals and levees were built in the area to drain and help develop economic and water resources including protection from floods and droughts. These construction projects have changed the natural water flow (hydropattern and hydroperiod) through the hydrologic system. Changes to the hydropattern and hydroperiod of the area have also had an adverse impact by disrupting the normal breeding patterns of species within the Everglades ecosystem

Florida

Fort Collins Science Center-Fiscal year 2011 science accomplishments

The Fort Collins Science Center (FORT) is a multi-disciplinary research and development center of the U.S. Geological Survey located in Fort Collins, Colorado. FORT research focuses on the needs of land- and water-management bureaus within the U.S. Department of the Interior, other Federal agencies, and State, Tribal, and non-government organizations. We emphasize a multi-disciplinary science approach to provide information for natural resource management decisionmaking. Our vision is to maintain and continuously improve the integrated, collaborative, world-class research needed to inform effective, science-based land management. The 2011 science accomplishments report provides an executive summary highlighting key achievements, an appendix of 68 one-page accomplishment descriptions organized by U.S. Geological Survey Mission Area, and a complete list of publications and other products generated in FY2011. The executive summary includes a table cross-referencing all major FY11 accomplishments with the various Mission Areas each supports.

Colorado

Summary of the land-use inventory for the nonpoint-source evaluation monitoring watersheds in Wisconsin

In 1992, the Wisconsin Department of Natural Resources (WDNR) in cooperation with the U.S. Geological Survey initiated a land-use inventory to identify sources of pollutants and track the land-management changes for eight evaluation monitoring watersheds established as part of the WDNR's Nonpoint Source Program. Each evaluation monitoring watershed is within a WDNR priority watershed. The U.S. Geological Survey is responsible for collection of water-quality data in the evaluation monitoring watersheds. An initial inventory was completed for each of the WDNR priority watersheds before nonpoint-source plans were developed for the control of nonpoint pollution. The land-use inventory described in this report expands upon the initial inventory by including nonpoint pollution sources that were not identified and also by updating changes in landuse and land-management practices. New sources of nonpoint pollution, not identified in the initial inventory, could prove to be important when monitored and modeled data are analyzed. This effort to inventory the evaluation monitoring watersheds will help with the interpretation of future land-use and water-quality data. This report describes landuse inventory methods, presents results of the inventory, and lists proposed future activities.

Wisconsin