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A selected bibliography of references on geology, hydrology, and geochemistry of the Midwestern Basins and Arches region; Ohio, Indiana, Michigan, and Illinois

This report contains selected references used for the Midwestern Basins and Arches Regional Aquifer System Analysis project of the U.S. Geological Survey. The project was begun in 1988 to study the geologic framework, hydrology, and geochemistry of the surficial and the Silurian and Devonian carbonate-rock aquifers in the Midwestern Basins and Arches Region. The area of data collection is 90,000 square miles and includes parts of Ohio, Indiana, Michigan, and Illinois. Geologic, hydrologic, and geochemical references that apply to the hydrogeology and geochemistry of the region were collected and are presented in this bibliography by State and by geologic, hydrologic, and geochemical categories for each State.

Open-File Report↗

Hydrologic and water-quality data for two small watersheds on Catoctin Mountain, North-Central Maryland, 1987-93

Hydrologic and water-quality data were collected from a precipitation-collection station and from two small watersheds on Catoctin Mountain, north-central Maryland, as part of investigations of acidic deposition and episodic acidification, and their effects on streamwater quality. Detailed descriptions of the site instrumentation in the watersheds, field data-collection techniques, and laboratory methods used to conduct the studies are included. Data that were collected on precipitation, throughfall, soil water, ground water, streamwater, and other surface and ground waters sampled during biannual synoptic surveys are given in tables. Data collected since October 1987 from one of the streamwater-quality monitoring sites and data collected since March 1988 from one of the ground-water quality monitoring sites are presented. Additional data collected since January 1987 from the precipitation station and data collected since June 1990 from all of the other water-quality monitoring sites are presented. Hydrologic data include tables of precipitation and throughfall quantities, streamflow, and synoptic measurements of ground-water levels. Selected hydrologic data are shown in graphs.

Maryland↗

Summary of surface-water hydrologic data for the Houston metropolitan area, Texas, water years 1964-89

The study area, a metropolitan area in southeast Texas about 45 miles north of the Gulf of Mexico, has been undergoing extensive urban development since the 1950s. The Houston Urban Runoff Program was begun by the U.S. Geological Survey in water year 1964 to define the magnitude and frequency of flood peaks, to determine the impact of continuing urban development on surface-water hydrologic responses, and to determine variations in stream water quality for different flow conditions, seasons, and urban development. An extensive data base has been developed. During water years 1964-89, the Houston Urban Runoff Program collected information from a total of 54 U.S. Geological Survey streamflow-gaging stations, 30 U.S. Geological Survey water-quality sampling sites, and 102 rain gages (operated by the U.S. Geological Survey, the National Weather Service, and local agencies). In addition, basin characteristics were developed to aid in understanding the effects of urban development on surface-water hydrologic responses. Surface-water hydrologic data on diskettes describe the 54 U.S. Geological Survey streamflow-gaging stations, list annual peaks (and where available, peaks above an arbitrary base) for 50 streamflow sites, tabulate 1,125 storm hydrographs from 43 sites, and document 102 waterquality parameters determined from 3,242 available samples.

Texas↗

Hydrologic data for Long Valley Caldera, Mono County, California, 1987-93

Hydrologic data were collected during 1987-93 as part of the U.S. Geological Survey's long-term Volcanic Hazards Monitoring Program of the Long Valley Caldera, Mono County, California. The data are presented in graphs or tables. Data collected for the Long Valley Hydrologic Advisory Committee monitoring program also are presented. Hydrologic data collected include continuous record of ground-water levels in 6 wells, instantaneous measurement of ground-water levels in 55 wells, continuous record of discharge at 2 streams and 5 springs, instantaneous discharge measurements at 4 streams and 2 springs, ground-water temperature profiles of 3 thermal wells, continuous record of water temperature in 1 stream and 5 springs, vent gas temperatures at 2 fumaroles, and chemical and isotopic analyses of water samples collected at 13 ground-water and 6 surface-water sites. Precipitation amounts at three sites also are included.

Open-File Report↗

Hydrologic description of the Braden River watershed, west-central Florida

The Braden River watershed drains an 83-square mile area in west-central Florida and is the largest tributary to the Manatee River. The hydrology of the Braden River was altered in 1936 when the city of Bradenton created Ward Lake, a reservoir with an 838-foot broad-crested weir 6 miles upstream from the mouth. In 1985 the reservoir, which is the sole source of drinking water for the city of Bradenton, was expanded and supplies an annual average of 5.7 million gallons of water per day. The Braden River can be hydrologically divided into three distinct sections that include an 8.6-mile reach of naturally incised, free-flowing channel; a 6.4-mile reach of impounded river created by the Ward Lake reservoir and weir; and a 6-mile reach of tidal estuary. Ten first-order and two second-order tributaries that flow into the Braden River were examined in this report. The Braden River watershed is dominated by low topographic relief. The two physiographic zones that contain the Braden River watershed, the Gulf Coast Lowlands and De Soto Plain, are both poorly drained and have numerous depressional features. The climate is subtropical with an annual average rainfall of 56 inches, annual average temperatures of 72 degrees Fahrenheit, and estimated annual lake evaporation of 52 inches. The soil series in the watershed are predominantly Myakka-Cassia and the EauGallie-Floridana; these series are characterized as nearly level and poorly drained soils. Land use within the watershed is the fastest changing characteristic that affects the hydrology of the system. The western half of the watershed is typically urban and includes parts of the city of Bradenton. Land use in the eastern half of the watershed is predominantly agricultural, but the explosive population growth of the area is driving the development of medium to high-density residential communities. The three major aquifers underlying the Braden River watershed are the surficial, intermediate, and Floridan aquifer systems. The surficial aquifer generally is underlain in places by a clay layer that enhances the ground-water flow of the surficial aquifer to surface-water bodies. The intermediate aquifer system has discontinuous water-bearing units, but retards ground-water movement between the surficial and Floridan aquifer system. The Floridan aquifer system consists of the Upper and Lower Floridan aquifers separated by a middle confining unit. The Upper Floridan aquifer is the primary source for ground-water withdrawals in the watershed and has, at times, heads 20 feet higher than land-surface elevation. Discharge over the Ward Lake weir into the tidal estuary was measured using volumetric and standard discharge measurement techniques. Annual mean flow for water years 1993 and 1994 were 59.7 and 57.3 cubic feet per second, respectively. Weir coefficients, calculated from discharge measurements, ranged from 0.023 to 2.99, depending on the head of water over the weir, and the method of determining length of flow on the weir. Weir coefficients calculated from the theoretical rating ranged from 0.032 to 3.11. No significant seepage was found around the ends of the weir, and no leakage was detected through the weir.

Florida↗

Hydrologic and water-quality data related to the occurrence of arsenic for areas along the Madison and Upper Missouri Rivers, southwestern and west-central Montana

Geothermal waters in Yellowstone National Park contribute large quantities of arsenic to the headwaters of the Madison River. Water in some Quaternary and Tertiary valley-fill deposits along the Madison and upper Missouri Rivers also is locally enriched in arsenic. Arsenic in surface and ground water in these valleys is an important public- health concern because arsenic concentrations frequently exceed the State of Montana water- quality human health standard of 18 micrograms per liter as well as the U.S. Environmental Protection Agency Maximum Contaminant Level of 50 micrograms per liter. This report presents hydrologic and water-quality data for the Madison and upper Missouri Rivers and selected tributaries, irrigation supply canals or ditches, drains, springs and seeps, for Lake Helena, and for ground water in adjacent areas. Hydrologic and water-quality data were collected and compiled to provide information to more fully understand the extent, magnitude, and source of arsenic in surface and ground water along the Madison and upper Missouri Rivers; to assess, to the extent possible, the mechanisms that control arsenic concentrations; and to assess the effect of irrigation on arsenic concentrations. Hydrologic and arsenic- concentration data were collected by the U.S. Geological Survey and other agencies for 104 surface-water sites and 273 ground-water sites during this and previous studies. The quality of analytical results for arsenic concentrations was evaluated by quality-control samples that were submitted from the field and analyzed in the laboratory with routing samples. Quality-control samples consisted of replicates, standard reference samples, interlaboratory comparison samples, and field blanks.

Open-File Report↗

Hydrologic data for the Columbia/Eagle Bluffs Wetland Complex, Columbia, Missouri-1993-96

The U.S. Geological Survey, in cooperation with the Missouri Department of Conservation and the city of Columbia, Missouri, collected hydrologic data from September 1993 through October 1996 as part of a hydrologic characterization of the Columbia/Eagle Bluffs Wetland Complex. The wetland complex was constructed in the Missouri River alluvial plain adjacent to the Columbia municipal supply wells. Part of the wetland complex was designed to treat sewage effluent from Columbia, with the treated effluent being used as the primary water source for wetland management practices on the Eagle Bluffs Wildlife Area. This report presents hydrologic data and the procedures used to collect the data, which include water-quality analyses of samples collected quarterly from 28 wells and 2 surface-water sites. Four additional wells were incorporated into the monitoring network in November 1994 and also were sampled quarterly. Data from these 4 wells also are included. Water samples were analyzed for specific conductance, pH, temperature, dissolved oxygen, bacteria, alkalinity, major cations and anions, nutrients, trace elements, and total and dissolved organic carbon. Dissolved nitrite plus nitrate as nitrogen concentrations were equal to or less than 5.2 milligrams per liter for all ground-water samples and were equal to or less than 2.7 milligrams per liter in surface-water samples. Dissolved phosphorous concentrations ranged from less than 0.01 to 2.2 milligrams per liter in the ground-water samples, and from less than 0.01 to 0.19 milli-grams per liter in the surface-water samples. Fecal coliform bacteria counts ranged from less than 1 to 39 colonies per 100 milliliters for ground-water samples, and from 1 to greater than 6,000 colonies per 100 milliliters for surface-water samples. Fecal streptococcus bacteria counts ranged from less than 1 to 92 colonies per 100 milliliters for ground-water samples, and from 2 to greater than 10,000 colonies per 100 milliliters for surface-water samples. Samples for well USGS-6 had dissolved arsenic concentrations that exceeded 50 micrograms per liter. Dissolved manganese concentrations exceeded 50 micrograms per liter at least once for each site except for USGS-9S. Dissolved iron concentrations exceeded 300 micro-grams per liter at least once for 28 of 34 sites. Samples from 8 of the 32 wells and both surface-water sites were analyzed for base/neutral/ acid semi-volatile organic compounds, selected pesticides, selected organochlorine compounds, and purgeable volatile organic compounds. All but one of the organic compounds detected in the samples collected from the monitoring wells or surface-water sites were pesticides. Atrazine was detected consistently at both surface-water sites. Other frequently detected pesticides include metolachlor, diazinon, chlorpyrifos, prometon, and simazine. Following the 1993 Missouri River flood samples of residual flood water and flood-deposited sediments were collected from the Columbia/ Eagle Bluffs Wetland Complex. A brief description of the flooding and damage to the study area is presented. Methods of collection of the four residual flood water and the four flood-deposited sediment samples, as well as the analytical results of these samples, are included in this report. Data from two continuous water-level recorders and from quarterly water-level measurements in wells also are included.

Missouri↗

Water resources and potential hydrologic effects of oil-shale development in the southeastern Uinta Basin, Utah and Colorado

Proposed oil-shale mining in northeastern Utah is expected to impact the water resources of a 3,000-square-mile area. This report summarizes a comprehensive hydrologic investigation of the area which resulted in 13 published reports. Hydrologic information obtained during 1974-80 was used to evaluate the availability of water and to evaluate potential impacts of an oil-shale industry on the water resources. The study area is the southeastern part of the Uinta Basin, Utah and Colorado, where the hydrology is extremely variable. The normal annual precipitation averages 11 inches and varies with altitude. It ranges from less than 8 inches at altitudes below 5,000 feet along the White and Green Rivers to more than 20 inches where altitudes exceed 9,000 feet on the Roan Plateau. The White and Green Rivers are large streams that flow through the area. They convey an average flow of 4.3 million acre-feet per year from outside drainage areas of about 34,000 square miles, which is more than 150 times as much flow as that originating within the area. Streams originating in areas where precipitation is less than 10 inches are ephemeral. Mean annual runoff from the study area is about 28,000 acre-feet and ranges from less than 0.1 to 1.6 inches, depending on the location. At any given site, runoff varies greatly-from year to year and season to season. Potential evapotranspiration is large, exceeding precipitation in all years. Three major aquifers occur in the area. They are alluvial deposits of small areal extent along the major stream valleys; the bird's-nest aquifer of the Parachute Creek Member of the Green River Formation, which is limited to the central part of the study area; and the Douglas Creek aquifer of the Douglas Creek Member of the Green River Formation, which underlies most of the area. Total recoverable water in storage in the three aquifers is about 18 million acre-feet. Yields of individual wells and interference between wells limit the maximum practical withdrawal to about 20,000 acre-feet per year. An oil-shale industry in the southeastern Uinta Basin with a peak production of 400,000 barrels of oil per day would require a water supply of about 70,000 acre-feet per year. Sources of water supply considered for such an industry were: diversion from the natural flow of the White River, a proposed reservoir on the White River, diversion from the White River combined with proposed off-stream storage in Hells Hole Canyon, diversion from the Green River, and conjunctive use of ground and surface water. The proposed reservoir on the White River would trap about 90 percent of the sediment moving in the river and in turn would release almost sediment-free water. Possible impacts are changes in channel gradient in the downstream 18 miles of the White River and changes in bank stability. In some parts of the area, annual sheet-erosion rates are as great as 2.2 acre-feet per square mile but sediment yield to the White River is less than might be expected because the runoff is small. If process water from retort operations or water used in the construction of surface facilities is discharged into a normally dry streambed, increased channel erosion and sediment in tributary streams could result in increased sediment loads in the White River. In addition, sediment yields from retorted-shale piles with minimum slopes could exceed 0.1 acrefoot per square mile during a common storm. Thus, without safeguards, the useful life of any proposed reservoir or holding pond could be decreased considerably. Leachate water from retorted-shale piles has large concentrations of sodium and sulfate, and the chemical composition of retort waters differs considerably from that of the natural waters of the area. The retort waters contain a greater concentration of dissolved solids and more organic carbon and nutrients. Without proper disposal or impoundment of retort and leachate waters, the salinity of downstream waters in the Colorado River Basin would be increased.

Colorado, Utah↗

Hydrology of the Bonneville Salt Flats, northwestern Utah, and simulation of ground-water flow and solute transport in the shallow-brine aquifer

This report describes the hydrologic system of the Bonneville Salt Flats with emphasis on the mechanisms of solute transport. Variable-density, three-dimensional computer simulations of the near-surface part of the ground-water system were done to quantify both the transport of salt dissolved in subsurface brine that leaves the salt-crust area and the salt dissolved and precipitated on the land surface. The study was designed to define the hydrology of the brine ground-water system and the natural and anthropogenic processes causing salt loss, and where feasible, to quantify these processes. Specific areas of study include the transport of salt in solution by ground-water flow and the transport of salt in solution by wind-driven ponds and the subsequent salt precipitation on the surface of the playa upon evaporation or seepage into the subsurface. In addition, hydraulic and chemical changes in the hydrologic system since previous studies were documented.

Utah↗

Hydrology and climate of four watersheds in eastern Puerto Rico: Chapter C in Water quality and landscape processes of four watersheds in eastern Puerto Rico

Puerto Rico lies directly in the path of the easterly trade winds, which deliver steady rainfall to the mountains and steer tropical wave systems toward the island. Hurricanes and tropical storms derived from these tropical waves differ in frequency and intensity, contributing to substantial interannual variation in precipitation and stream discharge. Puerto Rico's steep topography and small water-storage capacity leave the island's water supply and developed flood plains vulnerable to extreme weather events, such as hurricanes, floods, and droughts. This vulnerability may increase in the future owing to ongoing change, both local (such as land-cover shifts, water-supply projects, and construction of roads and other infrastructure) and regional (climate variability and change). Climate change, which could lead to more intense and prolonged droughts as well as an increase in the magnitude and frequency of destructive storms in the Caribbean, may alter temperature and affect the availability of water for human and ecosystem needs. Accurate assessment of hydrologic regimes and water budgets is therefore crucial for effective management of water resources. As part of the U.S. Geological Survey's Water, Energy, and Biogeochemical Budgets program, hydrologic and geomorphologic processes and stream chemistry of four small watersheds in eastern Puerto Rico, which differ in geology and land cover, have been studied since 1991. Spatial and temporal characteristics of precipitation and stream discharge, along with water budgets, were determined for the watersheds for the period 1991 to 2005. The locations of the watersheds relative to the Luquillo Mountains and the range's associated rain shadow dominate hydrological processes, dwarfing influences of land cover. The influence of geology is reflected in recession characteristics of the rivers (recession is faster in soils overlying volcaniclastic bedrock) and in hillslope geomorphic processes (sediment is delivered at higher rates from soils overlying granitic bedrock).

Professional Paper↗

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↗

Chloroform in the hydrologic system--sources, transport, fate, occurrence, and effects on human health and aquatic organisms

Chloroform is one of the volatile organic compounds (VOCs) detected most frequently in both ground and surface water. Because it is also one of the four trihalomethanes (THMs) produced in the highest concentrations during the chlorination of drinking water and wastewater, the frequent detection of this compound in ground and surface water of the United States is presumed to be caused primarily by the input of chlorinated water to the hydrologic system. Although anthropogenic sources of the compound are substantial, they are currently estimated to constitute only 10 percent of the total global input to the hydrologic system. Natural sources of the compound include volcanic gases, biomass burning, marine algae, and soil microorganisms. Under most conditions (except in the presence of unusually high bromide concentrations), chloroform is the THM produced in the highest concentrations during chlorination. Furthermore, in most cases where more than one THM is produced from chlorination, the relative concentrations among the different compounds usually decrease with increasing bromination (chloroform > dichlorobromomethane > chlorodibromomethane > bromoform). This phenomenon is presumed to be responsible for the common observation that when more than one THM is detected during investigations of the occurrence of these compounds in the hydrologic system, this same trend is typically observed among their relative concentrations or, for a uniform reporting limit, their relative frequencies of detection. This pattern could provide a valuable means for distinguishing between chlorinated water and other potential sources of chloroform in the environment. Chloroform has been widely detected in national, regional, and local studies of VOCs in ground, surface, source, and drinking waters. Total THM (TTHM) concentrations of the compound, however, were typically less than the Maximum Contaminant Level (MCL) of 80 ?g/L (micrograms per liter) established by the U.S. Environmental Protection Agency (USEPA) for TTHMs. In the studies that compared land-use settings, frequencies of detection of chloroform were higher beneath urban and residential areas than beneath agricultural or undeveloped areas. Because chloroform is a suspected human carcinogen, its presence in drinking water is a potential human health concern. Liver damage, however, is known to occur at chloroform exposures lower than those required to cause cancer, an observation that has been considered by the USEPA as the basis for setting a new, non-zero Maximum Contaminant Level Goal of 70 ?g/L for the compound. As part of its National Water-Quality Assessment Program, the U.S. Geological Survey has been assembling and analyzing data on the occurrence of VOCs (including chloroform) in ground and surface water on a national scale from studies conducted between 1991 and the present. This report presents a summary of current (2004) information on the uses, sources, formation, transport, fate, and occurrence of chloroform, as well as its effects on human health and aquatic organisms.

Scientific Investigations Report↗

Hydrology and cycling of nitrogen and phosphorus in Little Bean Marsh: A remnant riparian wetland along the Missouri River in Platte County, Missouri, 1996–97

The lack of concurrent water-quality and hydrologic data on riparian wetlands in the Midwestern United States has resulted in a lack of knowledge about the water-quality functions that these wetlands provide. Therefore, Little Bean Marsh, a remnant riparian wetland along the Missouri River, was investigated in 1996 and 1997 primarily to determine the magnitude and character of selected water-quality benefits that can be produced in such a wetland and to identify critical processes that can be managed in remnant or restored riparian wetlands for amelioration of water quality. Little Bean Marsh averages 69 hectares in size, has a maximum depth of about 1 meter, and the majority of the marsh is covered by macrophytes. In 1997, 41 percent of the water received by Little Bean Marsh was from direct precipitation, 14 percent was from ground-water seepage, 30 percent from watershed runoff, and 15 percent was backflow from Bean Lake. Although, Little Bean Marsh was both a ground-water recharge and discharge area, discharge to the marsh was three times the recharge to ground water. Ground-water levels closely tracked marsh water levels indicating a strong hydraulic connection between ground water and the marsh. Reduced surface runoff and ground-water availability are stabilizing influences on marsh hydrology and probably contribute to the persistence of emergent vegetation. The rapid hydraulic connection between Little Bean Marsh and ground water indicates that the hydrologic regime of most wetlands along the lower Missouri River is largely a function of the altitude of the marsh bottom relative to the altitude of the water table. More water was lost from the marsh through evapotranspiration (59 percent) than all other pathways combined. This is partially because the transpiration process of abundant macrophytes can greatly contribute to the evapotranspiration above that lost from open water surfaces. Surface outflow accounted for 36 percent and ground-water seepage accounted for only 5 percent of the losses. Large residence times allows the marsh to greatly affect water quality before water escapes as ground-water recharge or surface outflow. The shallowness of Little Bean Marsh and ion exclusion during ice formation caused the highest specific conductances of 1,100 to 1,300 microsiemens per centimeter at 25 degrees Celsius to occur during the winter. This concentration of dissolved solutes under ice can make wetlands more vulnerable to toxic contaminants than deeper surface-water bodies. Dissolved oxygen was less than 5 mg/L (milligrams per liter) for 3 to 4 months and near 0 mg/L for about 1 month in summer. Despite depths of less than 1 meter, temperature stratification persisted more than 3 months during the summers of 1996 and 1997, preventing mixing and contributing to periods of anoxia. Shallow depths and extended periods of anoxia in the marsh limit the ability of some organisms to escape high-temperature stress. Turbidity in Little Bean Marsh usually was low for several reasons: sediment loadings from the largely flood-plain drainage were low, emergent vegetation shade out algae and shield the water from wind, and high concentrations of bivalent cations increase flocculation rates of inorganic suspended material. The high concentrations of bivalent cations was largely because of a substantial amount of ground-water seepage into the marsh. Dissolved organic nitrogen was the dominant nitrogen species in Little Bean Marsh. Denitrification and biotic uptake kept more than 62 percent of nitrate (NO3) and 43 percent of ammonium (NH4) concentrations in marsh samples less than a detection limit of 0.005 mg/L. This contrasts with the Missouri River where inorganic NO3 dominates. Consequently, artificial flood-plain drainage that bypasses riparian wetlands likely deliver substantially more biotically available inorganic nitrogen to receiving waters than surface water that has been routed through a remnant wetland. Average total nitrogen concentrations in Little Bean Marsh were substantially less than those at other Missouri River wetlands, roughly one-half the mean concentrations in the Missouri River, but roughly twice the average nitrogen values in reservoirs of the glaciated plains of Missouri. The largest concentrations of nearly all species of nitrogen and phosphorus and the most intense period of hypereutrophy coincided with a phytoplankton bloom and senescence of River Bulrush (Scirpus fluviatilis) and common cattail (Typha latifolia) in September 1997. The rapid leaching of nitrogen that occurs soon after macrophyte senescence combined with a recent destratification of the marsh probably provided nitrogen to the nitrogen-limited open-water areas and triggered a phytoplankton bloom. Despite the rarity of runoff events, surface runoff from the watershed, combined with atmospheric deposition, contributed more than seven times the 530 kg (kilograms) of nitrogen that escaped Little Bean Marsh in surface outflow during 1997. Atmospheric deposition alone was more than 530 kg. Seepage to ground water contained less than 1.5 percent of the nitrogen leaving the marsh in surface outflow. The slow decay rate of Scirpus fluviatilis and reducing conditions in bottom sediments make burial of organic nitrogen a substantial sink of nitrogen. Denitrification experiments indicate that denitrification rates were limited by NO3 in the water column. Consequently, decomposition and nitrification of NH4 and organic nitrogen are the rate limiting steps of nitrogen removal in Little Bean Marsh. The NO3-limited rates of denitrification also indicate that Little Bean Marsh has a large unused capacity for nitrogen removal. These data indicate that the vast extent of riparian marshes along the Missouri and Mississippi Rivers may have had a substantial role in limiting NO3 loads to the Gulf of Mexico before agricultural development of flood plains. Drainage and removal of riparian marshes may be a major cause of the increased NO3 loads to the Gulf of Mexico. Periods of anoxia had much larger effects on phosphorus release than the other variables. The largest concentrations of phosphorus occurred in late summer and corresponded with senescing macrophytes, periods of anoxia, and a large algal bloom in Little Bean Marsh. Low water levels prevented the escape of phosphorus in surface outflow during these periods of highest phosphorus concentrations. Dry weather in late summer is typical and probably makes the correspondence of low water levels, anoxia, and consequent low phosphorus release a common occurrence in marshes along the Missouri River. Little Bean Marsh retained more than 95 percent of the phosphorus it received. The amount of phosphorus in surface inflows to the marsh were more than one order of magnitude greater than that escaping in surface outflows. The long hydraulic residence time of the marsh and large contributions of iron from ground water (that provide many sorption sites for phosphorus) make the marsh an effective sediment and phosphorus trap.

Missouri↗

Hydrologic and water-quality characteristics for Bear Creek near Silver Hill, Arkansas, and selected Buffalo River sites, 1999-2004

The purpose of this report is to describe and compare the hydrologic and water-quality characteristics of Bear Creek near Silver Hill, Arkansas, to two sites on the Buffalo River upstream from the confluence of Bear Creek, to a site on Calf Creek, a smaller tributary to the Buffalo River, to selected undeveloped sites across the Nation, and to a developed site in Arkansas. A better understanding of the hydrology and water quality of Bear Creek is of interest to many, including the National Park Service, which administers the Buffalo National River, to evaluate its effects on the hydrology and water quality of the Buffalo River. The streamflow at Bear Creek near Silver Hill varied seasonally and annually from January 1999 to March 2004. The mean annual streamflow at Bear Creek for calendar years 1999 to 2003 was 86.0 cubic feet per second. The highest annual mean streamflow occurred in 2002 (158 cubic feet per second) and the lowest annual mean streamflow occurred in 1999 (56.4 cubic feet per second). The mean annual streamflow for calendar years 1999 to 2003 at the Buffalo River near Boxley and Buffalo River near St. Joe was 102 and 881 cubic feet per second, respectively. Concentrations of nitrogen measured for Bear Creek generally were greater than concentrations measured at the two Buffalo River sites and were similar to concentrations measured at Calf Creek. Concentrations of phosphorus measured at Bear Creek generally were greater than concentrations measured at the two Buffalo River sites and were similar to concentrations measured at Calf Creek. Fecal indicator bacteria concentrations generally were greater at Bear Creek than concentrations measured at the Buffalo River and similar to concentrations at Calf Creek. Bear Creek had significantly greater suspended-sediment concentrations than the Buffalo River near Boxley and the Buffalo River near St. Joe and similar concentrations to Calf Creek. Nutrients, dissolved organic carbon, and suspended-sediment loads at Bear Creek and two Buffalo River sites varied because of differences in land use and contributing drainage area for each site. In general, the Buffalo River near St. Joe had the greatest annual loads of nutrients, dissolved organic carbon, and suspended sediment. The Buffalo River near Boxley had the least annual nutrient and suspended-sediment loads amongthe three sites. Buffalo River near Boxley had lesser annual loads than the other two sites probably because of the higher percentage of forested land in the basin and smaller contributing drainage area. Mean annual nutrient, dissolved organic carbon, and suspended- sediment yields computed for Bear Creek were greater than yields computed for both of the Buffalo River sites. Bear Creek had greater median annual nutrient yields than selected undeveloped basins across the Nation and less median annual nutrient yields than the Illinois River south of Siloam Springs, Arkansas, which is representative of a developed basin. Bear Creek had greater median annual flow-weighted nutrient concentrations than the Buffalo River near St. Joe, the Buffalo River near Boxley, and selected undeveloped sites across the Nation. Bear Creek had less median flow-weighted nutrient concentrations than the Illinois River.

Scientific Investigations Report↗

Regionalized equations for bankfull-discharge and channel characteristics of streams in New York State—Hydrologic Region 7 in western New York

Computation of bankfull discharge and channel dimensions (width, depth, and cross-sectional area) at ungaged sites requires equations that relate bankfull discharge and channel dimensions to drainage-area at gaged sites. Bankfull-channel information commonly is needed for watershed assessments, stream channel classification, and the design of stream-restoration projects. Such equations are most accurate if they are derived on the basis of data from streams within a region of uniform hydrologic, climatic, and physiographic conditions and applied only within that region. New York State contains eight hydrologic regions that were previously delineated on the basis of high-flow (flood) characteristics. This report presents drainage areas and associated bankfull characteristics (discharge and channel dimensions) for surveyed streams in western New York (Region 7). Stream-survey data and discharge records from seven active and three inactive USGS streamflow-gaging stations were used in regression analyses to relate drainage area to bankfull discharge and to bankfull channel width, depth, and cross-sectional area. The resulting equations are: (1) bankfull discharge, in cubic feet per second = 37.1*(drainage area, in square miles) 0.765 ; (2) bankfull channel width, in feet = 10.8*(drainage area, in square miles) 0.458 ; (3) bankfull channel depth, in feet = 1.47*(drainage area, in square miles) 0.199 ; and (4) bankfull channel cross-sectional area, in square feet = 15.9*(drainage area, in square mile) 0.656 . The coefficients of determination (R 2 ) for these four equations were 0.94, 0.89, 0.52, and 0.96, respectively. The high coefficients of determination for three of these equations (discharge, width, and cross-sectional area) indicate that much of the range in the variables was explained by the drainage area. The low coefficient of determination for the equation relating bankfull depth to drainage area, however, suggests that other factors also affected water depth. Recurrence intervals for the estimated bankfull discharge of each stream ranged from 1.05 to 3.60 years; the mean recurrence interval was 2.13 years. The 10 surveyed streams were classified by Rosgen stream type; most were C- and E-type, with occasional B- and F-type cross sections. The equation (curve) for bankfull discharge for Region 7 was compared with those previously developed for four other hydrologic regions in New York State. The differences confirm that the hydraulic geometry of streams is affected by local climatic and physiographic conditions.

Scientific Investigations Report↗

Watershed characteristics and pre-restoration surface-water hydrology of Minebank Run, Baltimore County, Maryland, water years 2002-04

Stream restoration efforts have been ongoing in Maryland since the early 1990s. Physical stream restoration often involves replacement of lost sediments to elevate degraded streambeds, re-establishment of riffle-pool sequences along the channel profile, planting vegetation in riparian zones, and re-constructing channel banks, point bars, flood plains, and stream-meanders. The primary goal of many restoration efforts is to re-establish geomorphic stability of the stream channel and reduce erosive energy from urban runoff. Monitoring streams prior to and after restoration could help quantify other possible benefits of stream restoration, such as improved water quality and biota. This report presents general watershed characteristics associated with the Minebank Run watershed; a small, urban watershed in the south-central section of Baltimore County, Maryland that was physically restored in phases during 1999, 2004, and 2005. The physiography, geology, hydrology, land use, soils, and pre-restoration geomorphic setting of the unrestored stream channel are discussed. The report describes a reach of Minebank Run that was selected for the purpose of collecting several types of environmental data prior to restoration, including continuous-record and partial-record stage and streamflow data, precipitation, and ground-water levels. Examples of surface-water data that were collected in and near the study reach during water years 2002 through 2004, including continuous-record streamflow, partial-record stage and discharge, and precipitation, are described. These data were used in analyses of several characteristics of surface-water hydrology in the watershed, including (1) rainfall totals, storm duration, and intensity, (2) instantaneous peak discharge and daily mean discharge, (3) stage-discharge ratings, (4) hydraulic-geometry relations, (5) water-surface slope, (6) time of concentration, (7) flood frequency, (8) flood volume, and (9) rainfall-runoff relations. Several hydrologic characteristics that are typical of urban environments were quantified by these analyses. These include (1) large ratios of peak discharge to daily mean discharge as an indicator of flashiness, (2) consistent shifting of the stage-discharge rating over short periods of time that indicates instability of the stream channel, (3) analyses of hydraulic-geometry relations that indicate mean velocities of 11 feet per second or more while the flow is contained in the stream channel, (4) discharges that are 4 to 5 times larger in Minebank Run for corresponding flood frequency recurrence intervals than in Slade Run, which is a Piedmont watershed of similar size with smaller percentages of urban development, and (5) flood waves that can travel through the stream channel at a velocity of 412 feet per minute, or 6.9 feet per second.

Maryland↗

Hydrologic Characteristics of a Managed Wetland and a Natural Riverine Wetland along the Kankakee River in Northwestern Indiana

Characteristics of ground-water/surface-water interactions were identified at a managed wetland (Hog Marsh) and a natural riverine wetland (LaSalle) located on the north and south sides, respectively, of the Kankakee River in northwestern Indiana. Hog Marsh covers about 390 hectares of the Grand Kankakee Marsh County Park. LaSalle covers about 100 hectares of the LaSalle State Fish and Wildlife Area, and is about 20 kilometers downstream of Hog Marsh. Hydrologic characteristics of the two wetlands were investigated using data from 1997 to 1999 for 22 wells adjacent to the Kankakee River in northwestern Indiana. Surface-water levels at the managed wetland were controlled by a system of channels, levees, and managed flooding. Surface-water levels at the natural riverine wetland were not controlled. Ground-water levels in the unconfined surficial aquifer beneath the two wetlands were analyzed by assessing water-level fluctuations. Fifteen wells at Hog Marsh and seven wells at LaSalle were monitored. The interquartile range in ground-water levels away from the river at Hog Marsh fluctuated less (from 0.4 to 0.7 meters) than all ground-water levels in the same aquifer beneath LaSalle (from 0.9 to 1.0 meters). The difference in the range of water-level fluctuation probably is attributable to the managed flooding of Hog Marsh units, which tends to maintain somewhat uniform water levels in that wetland. Ground-water-flow directions along a vertical section through the unconfined surficial aquifer at the managed wetland were more variable than those at the natural riverine wetland. During winter and spring, when flow in the Kankakee River is high, flow is from the Kankakee River into the adjacent surficial aquifer and towards a 2-meter-wide Brown Ditch on the north side of Hog Marsh. Water levels in Brown Ditch remain lower than those in the Kankakee River during this period. From June to December, when flow in the Kankakee River is moderate to low, a flow divide developed near the center of the managed wetland. Ground-water flow south of the divide is to the Kankakee River; north of the divide, it is toward Brown Ditch. Slight ground-water mounding near the center of the managed wetland is accentuated by water-management practices that intentionally flood that area. Ground-water flow in the surficial aquifer at the natural riverine wetland was not impeded by ditches or managed flooding, and a simple flow-through system from areas south of the Kankakee River to the river was observed. A ground-water flow model was constructed along a representative cross section through the surficial aquifer at the managed wetland and calibrated using data collected at the site. A no-flow boundary was used beneath the Kankakee River, and head-dependent boundaries were used along the north end of the model and at the base of the model. The model simulations indicated that artificial controls on the managed-wetland hydrology create sites of recharge to and discharge from the surficial aquifer that are absent at the natural riverine wetland. The steady-state flow simulation represented flow conditions following a 4-month period of no changes in hydrologic stresses. The simulation results indicated that flow paths originating from flooded areas near the center of the managed wetland are sources of aquifer recharge during the managed-flooding period. Brown Ditch captured almost all of the ground water north of the managed wetland. The simulated water budget along a well transect indicated that 88 percent of inflow to the surficial aquifer beneath the managed wetland was from a distribution channel and from flooding in the management units. These modeling results identify differences in flow patterns between the managed and natural riverine wetlands in addition to those identified by the water-level data. Results of transient simulations indicated that surface water from the Kankakee River penetrated only about 2 to 3 meters into the surficial aquif

Indiana↗

Hydrologic conditions and water-quality conditions following underground coal mining in the North Fork of the Right Fork of Miller Creek drainage basin, Carbon and Emery Counties, Utah, 2004-2005

In 2004 and 2005, the U.S. Geological Survey, in cooperation with the Bureau of Land Management, reassessed the hydrologic system in and around the drainage basin of the North Fork of the Right Fork (NFRF) of Miller Creek, in Carbon and Emery Counties, Utah. The reassessment occurred 13 years after cessation of underground coal mining that was performed beneath private land at shallow depths (30 to 880 feet) beneath the NFRF of Miller Creek. This study is a follow-up to a previous USGS study of the effects of underground coal mining on the hydrologic system in the area from 1988 to 1992. The previous study concluded that mining related subsidence had impacted the hydrologic system through the loss of streamflow over reaches of the perennial portion of the stream, and through a significant increase in dissolved solids in the stream. The previous study also reported that no substantial differences in spring-water quality resulted from longwall mining, and that no clear relationship between mining subsidence and spring discharge existed. During the summers of 2004 and 2005, the USGS measured discharge and collected water-quality samples from springs and surface water at various locations in the NFRF of Miller Creek drainage basin, and maintained a streamflow-gaging station in the NFRF of Miller Creek. This study also utilized data collected by Cyprus–Plateau Mining Corporation from 1992 through 2001. Of thirteen monitored springs, five have discharge levels that have not returned to those observed prior to August 1988, which is when longwall coal mining began beneath the NFRF of Miller Creek. Discharge at two of these five springs appears to fluctuate with wet and dry cycles and is currently low due to a drought that occurred from 1999–2004. Discharge at two other of the five springs did not increase with increased precipitation during the mid-1990s, as was observed at other monitored springs. This suggests that flowpaths to these springs may have been altered by land subsidence caused by underground coal mining. Analysis of possible impacts to the fifth spring were inconclusive due to a lack of data collected during the mid-1990s. Discharge at eight other monitored springs in the study area appears to be controlled mainly by climatic fluctuations and was generally near the value measured prior to 1988. Discharge at one of these eight springs is significantly greater than that measured during the longwall mining period. Concentrations of magnesium, calcium, sulfate, and dissolved solids at one undermined spring were elevated in relation to other springs in the study area. Dissolved solids concentration at this spring ranged from 539–709 milligrams per liter. Dissolved-solids concentration for all other springs in the study area ranged from 163 to 360 milligrams per liter and was near the median value measured prior to longwall mining beneath the NFRF of Miller Creek drainage basin. Baseflow measured at a streamflow-gaging station on the NFRF of Miller Creek located downstream of the mined area during the summer of 2004 was near 5 gallons per minute. Baseflow in 2005 increased to 7–8 gallons per minute, due to increased precipitation. This is slightly greater than the range of baseflow measured near the end of the longwall mining period which was approximately 3–5 gallons per minute. Seepage investigations carried out in the summer of 2004 and 2005 along the NFRF of Miller Creek showed a net loss of surface flow along the studied reach. Specific areas within the study reach had streamflow losses prior to longwall mining, however, the study reach as a whole was observed to gain in discharge when measured in 1986–1988, immediately before longwall mining began. The area where the greatest loss in discharge from the NFRF of Miller Creek occurred corresponds to an area where overburden (material overlying a deposit of useful geological materials or bedrock) is between 700 and 210 feet thick. Overburden thickness at the place where the streambed first dried up was approximately 600 feet thick. In 2004, approximately 1,600 ft of the streambed of the NFRF of Miller Creek was dry. Only 300 feet of the streambed was dry during the wetter year of 2005. Prior to longwall mining, no dry reaches were observed, though seepage loss was documented. Average discharge measured at a tributary to the NFRF of Miller Creek has increased from 1.6 gallons per minute measured during longwall mining to 7.2 gallons per minute measured in 2004–2005. During both years of this study, the lower reach of the stream regained flow from this tributary and from seepage gains. Water quality in the lower reach of the NFRF of Miller Creek downstream of the longwall-mined area, showed significantly higher concentrations of magnesium, calcium, sulfate, and strontium, in relation to water in the upper reach of the NFRF of Miller Creek and to the springs sampled in the area. Dissolved-solids concentration measured in the lower reach of the stream in 2004 and 2005 ranged from 1,880 to 2,220 milligrams per liter, while sulfate concentrations ranged from 1,090 to 1,320 mg/L. The maximum contaminant level for drinking water in the state of Utah for dissolved solids and sulfate is 2,000 and 1,000 mg/L respectively. Concentrations of these ions are slightly greater than those measured during and just following mining beneath the NFRF of Miller Creek drainage basin, but are significantly higher than those measured prior to mining. With the exception of strontium, dissolved metals concentrations in the NFRF of Miller Creek were similar to those measured in area springs. pH in the creek and at all spring sites was near neutral. Qualitative observations of the creek bottom suggest that mining-related activities have had little effect on vegetative growth.

Utah↗