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At least 19 recordsLinked to original sources
USGS2005

Summary of significant results from studies of triazine herbicides and their degradation products in surface water, ground water, and precipitation in the midwestern United States during the 1990s

Nonpoint-source contamination of water resources from triazine herbicides has been a major water-quality issue during the 1990s in the United States. To address this issue, studies of surface water, ground water, and precipitation have been carried out by the U.S. Geological Survey in the Midwestern United States. Reconnaissance studies of 147 streams were conducted to determine the geographic and seasonal distribution of atrazine, cyanazine, propazine, and simazine. These studies showed that high concentrations of herbicides were flushed from cropland and transported through the stream system as pulses in response to spring and summer rainfall. The studies also revealed the persistence of herbicides and their degradation products in streams. An investigation of 76 reservoirs showed that the occurrence and temporal distribution of herbicides and their degradation products in reservoir outflow could be related to reservoir and drainage-basin characteristics, water and land use, herbicide use, and climate. Significant findings showed that concentrations of atrazine and its degradation products remained elevated all summer and into the fall and that recently applied atrazine mixed with atrazine applied the previous year as water moved through a reservoir. Reconnaissance studies of 303 ground-water wells were completed to determine hydrogeological and seasonal occurrence, concentration, and distribution of herbicides and their degradation products. Samples collected from across the Midwestern United States consistently revealed that triazine herbicide degradation products commonly were found more frequently than their parent herbicide and that ground-water age could be an important factor in explaining variations in herbicide contamination. A final study investigated precipitation in the Midwestern United States, northeast to the Atlantic Ocean, and northward to the Canadian border. It found that the highest herbicide concentrations in precipitation occurred following herbicide application to cropland. Atrazine was detected most often, followed by deethylatrazine, cyanazine, and deisoproplyatrazine. Mass deposition of herbicides by precipitation was greatest in areas where herbicide use was intense and decreased with distance from the Midwest. Findings of the 1990s studies include an improved understanding of the occurrence, persistence, chemistry, and transport of triazine herbicides and their degradation products in the hydrologic environment. A significant increase in knowledge of triazine herbicides and development and improvement of analytical methods were accomplished in the past decade. The results produced are not only significant for the present (2005) but provide an important data set for future use.

Midwest region↗
USGS2002

Surface water-ground water interactions along the lower Dungeness River and vertical hydraulic conductivity of streambed sediments, Clallam County, Washington, September 1999-July 2001

The Dungeness River emerges from the Olympic Mountains and flows generally north toward the Strait of Juan De Fuca, crossing the broad, fertile alluvial fan of the Sequim-Dungeness peninsula in northeastern Clallam County, Washington. Increasing competition for the peninsula's ground-water resources, changing water-use patterns, and recent requirements to maintain minimum in-stream flows to enhance endangered salmon and trout populations have severely strained the peninsula's water resources and necessitated a better understanding of the interaction between surface water and groundwater. Three methods were used to characterize the interchange between surface water and groundwater along the lower 11.8 miles of the Dungeness River corridor between September 1999 and July 2001. In-stream mini-piezometers were used to measure vertical hydraulic gradients between the river and the water-table aquifer at 27 points along the river and helped to define the distribution of gaining and losing stream reaches. Seepage runs were used to quantify the net volume of water exchanged between the river and ground water within each of five river reaches, termed 'seepage reaches.' Continuous water-level and water-temperature monitoring at two off-stream well transects provided data on near-river horizontal hydraulic gradients and temporal patterns of water exchange for a representative gaining stream reach and a representative losing stream reach. Vertical hydraulic gradients in the mini-piezometers generally were negative between river miles 11.8 and 3.6, indicating loss of water from the river to ground water. Gradients decreased in the downstream direction from an average of -0.86 at river mile 10.3 to -0.23 at river mile 3.7. Small positive gradients (+0.01 to +0.02) indicating ground-water discharge occurred in three localized reaches below river mile 3.7. Data from the seepage runs and off-stream transect wells supported and were generally consistent with the mini-piezometer findings. An exception occurred between river miles 8.1 and 5.5 where seepage results showed a small gain and the mini-piezometers showed negative gradients. Vertical hydraulic conductivity of riverbed sediments was estimated using hydraulic gradients measured with the mini-piezometers and estimated seepage fluxes. The resulting conductivity values ranged from an average of 1 to 29 feet per day and are similar to values reported for similar river environments elsewhere. The results of this study will be used to calibrate a transient, three-dimensional ground-water flow model of the Sequim-Dungeness peninsula. The model will be used to assess the potential effects on ground-water levels and river flows that result from future water use and land-use changes on the peninsula.

Washington↗
USGS1999

Surface water-ground water interaction: Herbicide transport into municipal collector wells

During spring runoff events, herbicides in the Platte River are transported through an alluvial aquifer into collector wells located on an island in the river in 6 to 7 d. During two spring runoff events in 1995 and 1996, atrazine [2-chloro-4-ethylamino-6-isopropylamino- s -triazine] concentrations in water from these wells reached approximately 7 µg/L, 70 times more than the background concentration in ground water. Concentrations of herbicides and metabolites in the collector wells generally were one-half to one-fifth the concentrations of herbicides in the river for atrazine, alachlor [2-chloro-2′-6′-diethyl- N -(methoxymethyl)-acetanilide], alachlor ethane-sulfonic acid (ESA) [2-((2,6-diethylphenyl) (methoxymethyl)amino)-2-oxoethane-sulfonic acid], metolachlor [2-chloro- N -(2-ethyl-6-methylphenyl)- N -(2-methoxy-1-methylethyl)acetamide], cyanazine [2-((4-chloro-6-(ethylamino)-1,3,5 triazin-2-yl)-amino)-2-methylpropionitrile], and acetochlor [2-chloro- N -(ethoxymethyl)- N -(2-ethyl-6methyl-phenyl) acetamide], suggesting that 20 to 50% river water could be present in the water from the collector wells, assuming no degradation. The effect of the river on the quality of water from the collector wells can be reduced through selective management of horizontal laterals of the collector wells. The quality of the water from the collector wells is dependent on the (i) selection of the collector well used, (ii) number and selection of laterals used, (iii) chemical characteristics of the contaminant, and (iv) relative mixing of the Platte River and a major upstream tributary.

Journal of Environmental Quality↗
USGS1996

Effects of the eruptions of Mount St. Helens on physical, chemical, and biological characteristics of surface water, ground water, and precipitation in the Western United States

Over 120 publications that describe the 1980 eruption effects of Mount St. Helens on rivers, lakes, and the Columbia River estuary are reviewed. Water-quality changes ranged from minor, short-lived effects, to totally altered drainage basins and newly created lakes. Turbidity increased; concentrations of cations, anions, and dissolved organic carbon increased. Migrating fish were adversely affected; benthic-invertebrate populations changed. Ground-water levels rose near the Cowlitz River. Precipitation effects included transient, but increased specific conductance and decreased pH.

Water Supply Paper↗
USGS2000

The Phosphoria Formation at the Hot Springs Mine in Southeast Idaho: A source of selenium and other trace elements to surface water, ground water, vegetation, and biota

Major-element oxides and trace elements in the Phosphoria Formation at the Hot Springs Mine, Idaho were determined by a series of techniques. In this report, we examine the distribution of trace elements between the different solid components aluminosilicates, apatite, organic matter, opal, calcite, and dolomite that largely make up the rocks. High concentrations of several trace elements throughout the deposit, for example, As, Cd, Se, Tl, and U, at this and previously examined sites have raised concern about their introduction into the environment via weathering and the degree to which mining and the disposal of mined waste rock from this deposit might be accelerating that process. The question addressed here is how might the partitioning of trace elements between these solid host components influence the introduction of trace elements into ground water, surface water, and eventually biota, via weathering? In the case of Se, it is partitioned into components that are quite labile under the oxidizing conditions of subaerial weathering. As a result, it is widely distributed throughout the environment. Its concentration exceeds the level of concern for protection of wildlife at virtually every trophic level.

Idaho↗
USGS1977

Water resources data for Florida, water year 1976; Volume 4. Northwest Florida--surface water, ground water, and quality of water

Water resources data for the 1976 water year for northwest Florida consist of records of stage, discharge, and water quality of streams; elevation and water quality of lakes and reservoirs; water-levels and water quality of wells; and discharge and water quality of springs. Additional water data were collected at various sites, not part of the systematic data collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating state and federal agencies in Florida.

Florida↗
USGS1976

Water resources data for Florida, water year 1975; Volume 1. Northern Florida--surface water, ground water, and quality of water

Water resources data for the 1975 water year for northern Florida consist of records of stage, discharge, and water quality of streams; elevation and water quality of lakes and reservoirs; water-levels and water quality of wells; and discharge and water quality of springs. Additional water data were collected at various sites, not part of the systematic data collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U. S. Geological Survey and cooperating state and federal agencies in Florida.

Florida↗
USGS1977

Water resources data for Florida, water year 1976; Volume 2. South Florida--surface water, ground water, and quality of water

Water resources data for the 1976 water year for south Florida consist of records of stage, discharge, and water quality of streams; elevation and water quality of lakes and reservoirs; water-levels and water quality of wells; and discharge and water quality of springs. Additional water data were collected at various sites, not part of the systematic data collection program, and are published as miscellaneous measurements. These data represent that part of the National Water Data System operated by the U. S. Geological Survey and cooperating state and federal agencies in Florida.

Florida↗
USGS2013

Variations in surface water-ground water interactions along a headwater mountain stream : comparisons between transient storage and water balance analyses

The accumulation of discharge along a stream valley is frequently assumed to be the primary control on solute transport processes. Relationships of both increasing and decreasing transient storage, and decreased gross losses of stream water have been reported with increasing discharge; however, we have yet to validate these relationships with extensive field study. We conducted transient storage and mass recovery analyses of artificial tracer studies completed for 28 contiguous 100 m reaches along a stream valley, repeated under four base-flow conditions. We calculated net and gross gains and losses, temporal moments of tracer breakthrough curves, and best fit transient storage model parameters (with uncertainty estimates) for 106 individual tracer injections. Results supported predictions that gross loss of channel water would decrease with increased discharge. However, results showed no clear relationship between discharge and transient storage, and further analysis of solute tracer methods demonstrated that the lack of this relation may be explained by uncertainty and equifinality in the transient storage model framework. Furthermore, comparison of water balance and transient storage approaches reveals complications in clear interpretation of either method due to changes in advective transport time, which sets a the temporal boundary separating transient storage and channel water balance. We have little ability to parse this limitation of solute tracer methods from the physical processes we seek to study. We suggest the combined analysis of both transient storage and channel water balance more completely characterizes transport of solutes in stream networks than can be inferred from either method alone.

Montana↗
USGS2004

Precipitation; ground-water age; ground-water nitrate concentrations, 1995-2002; and ground-water levels, 2002-03 in Eastern Bernalillo County, New Mexico

The eastern Bernalillo County study area consists of about 150 square miles and includes all of Bernalillo County east of the crests of the Sandia and Manzanita Mountains. Soil and unconsolidated alluvial deposits overlie fractured and solution-channeled limestone in most of the study area. North of Interstate Highway 40 and east of New Mexico Highway 14, the uppermost consolidated geologic units are fractured sandstones and shales. Average annual precipitation at three long-term National Oceanic and Atmospheric Administration precipitation and snowfall data-collection sites was 14.94 inches at approximately 6,300 feet (Sandia Ranger Station), 19.06 inches at about 7,020 feet (Sandia Park), and 23.07 inches at approximately 10,680 feet (Sandia Crest). The periods of record at these sites are 1933-74, 1939-2001, and 1953-79, respectively. Average annual snowfall during these same periods of record was 27.7 inches at Sandia Ranger Station, 60.8 inches at Sandia Park, and 115.5 inches at Sandia Crest. Seven precipitation data-collection sites were established during December 2000-March 2001. Precipitation during 2001-03 at three U.S. Geological Survey sites ranged from 66 to 94 percent of period-of-record average annual precipitation at corresponding National Oceanic and Atmospheric Administration long-term sites in 2001, from 51 to 75 percent in 2002, and from 34 to 81 percent during January through September 2003. Missing precipitation records for one site resulted in the 34-percent value in 2003. Analyses of concentrations of chlorofluorocarbons CFC-11, CFC-12, and CFC-113 in ground-water samples from nine wells and one spring were used to estimate when the sampled water entered the ground-water system. Apparent ages of ground water ranged from as young as about 10 to 16 years to as old as about 20 to 26 years. Concentrations of dissolved nitrates in samples collected from 24 wells during 2001-02 were similar to concentrations in samples collected from the same wells during 1995, 1997, and (or) 1998. Nitrate concentrations in two wells were larger than the U.S. Environmental Protection Agency primary drinking-water regulation of 10 milligrams per liter in 1998 and in 2001. Ground-water levels were measured during June and July 2002 and during June, July, and August 2003 in 18 monitoring wells. The median change in water level for all 18 wells was a decline of 2.03 feet.

New Mexico↗
USGS2003

Characterization of lake water and ground water movement in the littoral zone of Williams Lake, a closed-basin lake in North central Minnesota

Williams Lake, Minnesota is a closed‐basin lake that is a flow‐through system with respect to ground water. Ground‐water input represents half of the annual water input and most of the chemical input to the lake. Chemical budgets indicate that the lake is a sink for calcium, yet surficial sediments contain little calcium carbonate. Sediment pore‐water samplers (peepers) were used to characterize solute fluxes at the lake‐water–ground‐water interface in the littoral zone and resolve the apparent disparity between the chemical budget and sediment data. Pore‐water depth profiles of the stable isotopes δ 18 O and δ 2 H were non‐linear where ground water seeped into the lake, with a sharp transition from lake‐water values to ground‐water values in the top 10 cm of sediment. These data indicate that advective inflow to the lake is the primary mechanism for solute flux from ground water. Linear interstitial velocities determined from δ 2 H profiles (316 to 528 cm/yr) were consistent with velocities determined independently from water budget data and sediment porosity (366 cm/yr). Stable isotope profiles were generally linear where water flowed out of the lake into ground water. However, calcium profiles were not linear in the same area and varied in response to input of calcium carbonate from the littoral zone and subsequent dissolution. The comparison of pore‐water calcium profiles to pore‐water stable isotope profiles indicate calcium is not conservative. Based on the previous understanding that 40–50 % of the calcium in Williams Lake is retained, the pore‐water profiles indicate aquatic plants in the littoral zone are recycling the retained portion of calcium. The difference between the pore‐water depth profiles of calcium and δ 18 O and δ 2 H demonstrate the importance of using stable isotopes to evaluate flow direction and source through the lake‐water–ground‐water interface and evaluate mechanisms controlling the chemical balance of lakes.

Minnesota↗
USGS1998

A national look at nitrate contamination of ground water

Ground water provides drinking water for more than one-half of the Nation's population (Solley and others, 1993), and is the sole source of drinking water for many rural communities and some large cities. In 1990, ground water accounted for 39 percent of water withdrawn for public supply for cities and towns and 96 percent of water withdrawn by self-supplied systems for domestic use. A variety of chemicals, including nitrate, can pass through the soil and potentially contaminate ground water. Nitrate comes from nitrogen, a plant nutrient supplied by inorganic fertilizer and animal manure. Additionally, airborne nitrogen compounds given off by industry and automobiles are deposited on the land in precipitation and dry particles. Other nonagricultural sources of nitrate include lawn fertilizers, septic systems, and domestic animals in residential areas. Beneath agricultural lands, nitrate is the primary form of nitrogen. It is soluble in water and can easily pass through soil to the ground-water table. Nitrate can persist in ground water for decades and accumulate to high levels as more nitrogen is applied to the land surface every year. Knowing where and what type of risks to ground water exist can alert water-resource managers and private users of the need to protect water supplies. Although nitrate generally is not an adult public-health threat, ingestion in drinking water by infants can cause low oxygen levels in the blood, a potentially fatal condition (Spalding and Exner, 1993). For this reason, the U.S. Environmental Protection Agency (EPA) has established a drinking-water standard of 10 milligrams per liter (mg/L) nitrate as nitrogen (U.S. Environmental Protection Agency, 1995). Nitrate concentrations in natural ground waters are usually less than 2 mg/L (Mueller and others, 1995).

Water Conditioning and Purification↗
USGS2006

Modeling decadal timescale interactions between surface water and ground water in the central Everglades, Florida, USA

Surface-water and ground-water flow are coupled in the central Everglades, although the remoteness of this system has hindered many previous attempts to quantify interactions between surface water and ground water. We modeled flow through a 43,000 ha basin in the central Everglades called Water Conservation Area 2A. The purpose of the model was to quantify recharge and discharge in the basin's vast interior areas. The presence and distribution of tritium in ground water was the principal constraint on the modeling, based on measurements in 25 research wells ranging in depth from 2 to 37 m. In addition to average characteristics of surface-water flow, the model parameters included depth of the layer of 'interactive' ground water that is actively exchanged with surface water, average residence time of interactive ground water, and the associated recharge and discharge fluxes across the wetland ground surface. Results indicated that only a relatively thin (8 m) layer of the 60 m deep surfical aquifer actively exchanges surface water and ground water on a decadal timescale. The calculated storage depth of interactive ground water was 3.1 m after adjustment for the porosity of peat and sandy limestone. Modeling of the tritium data yielded an average residence time of 90 years in interactive ground water, with associated recharge and discharge fluxes equal to 0.01 cm d -1. 3H/3He isotopic ratio measurements (which correct for effects of vertical mixing in the aquifer with deeper, tritium-dead water) were available from several wells, and these indicated an average residence time of 25 years, suggesting that residence time was overestimated using tritium measurements alone. Indeed, both residence time and storage depth would be expected to be overestimated due to vertical mixing. The estimate of recharge and discharge (0.01 cm d-1) that resulted from tritium modeling therefore is still considered reliable, because the ratio of residence time and storage depth (used to calculated recharge and discharge) is much less sensitive to vertical mixing compared with residence time alone. We conclude that a small but potentially significant component of flow through the Everglades is recharged to the aquifer and stored there for years to decades before discharged back to surface water. Long-term storage of water and solutes in the ground-water system beneath the wetlands has implications for restoration of Everglades water quality.

Journal of Hydrology↗
USGS1996

Movement of agricultural chemicals between surface water and ground water, lower Cedar River basin, Iowa

Movement of agricultural chemicals alachlor, atrazine, cyanazine, deethylatrazine, deisopropylatrazine, and metolachlor between surface water and ground water is documented by data collected from May 1989 through July 1991 at an unfarmed study site adjacent to the Cedar River in Iowa. During periods of runoff, these chemicals moved from the Cedar River into the alluvial aquifer with bank-storage water. Results of simulation of ground-water flow conditions during March-April 1990 indicated that bank-storage water moving through the river bottom accounted for 70 percent of the total bank-storage water, whereas the remaining 30 percent moved through the riverbank. The largest concentrations of the chemicals in bank-storage water during 1990 were: alachlor, 2.1 micrograms per liter ( μ g/L); atrazine, 4.7 μ g/L; cyanazine, 3.2 μ g/L; deethylatrazine, 0.54 μ g/L; deisopropylatrazine, 0.33 μ g/L; and metolachlor, 2.2 μ g/L. Larger concentrations of some herbicides and their metabolites were detected in the ground water after the study site was inundated by floodwater between June and August 1990. The concentrations in a water sample from one well after this flooding on February 5, 1991, were: alachlor, 0.06 μ g/L; atrazine, 18 μ g/L; cyanazine, 1.3 μ g/L; deethylatrazine, 1.4 μ g/L; deisopropylatrazine, 0.40 μ g/L; and metolachlor, 7.0 μ g/L. During base-flow conditions, the movement of agricultural chemicals from ground water to surface water was quantified for two periods of time in 1989 and 1990 along a 117-kilometer reach of the Cedar River. The principal source of atrazine, deethylatrazine, deisopropylatrazine, and metolachlor in the Cedar River during base flow was ground water discharged directly from the alluvial aquifer adjacent to the Cedar River. This discharge exceeded the combined tributary inflow of the chemicals along the entire reach. Bank storage is probably an important source of agricultural chemicals discharged from the alluvial aquifer but becomes depleted with time after surface runoff. Herbicides discharged from the alluvial aquifer during periods of extended base flow entered the alluvial aquifer with ground-water recharge at some distance from the river. The movement of nitrate between surface water and ground water is minor, when compared to the herbicides, even though nitrite was detected in the Cedar River during runoff.

Iowa, Minnesota↗
USGS2008

Field Techniques for Estimating Water Fluxes Between Surface Water and Ground Water

This report focuses on measuring the flow of water across the interface between surface water and ground water, rather than the hydrogeological or geochemical processes that occur at or near this interface. The methods, however, that use hydrogeological and geochemical evidence to quantify water fluxes are described herein. This material is presented as a guide for those who have to examine the interaction of surface water and ground water. The intent here is that both the overview of the many available methods and the in-depth presentation of specific methods will enable the reader to choose those study approaches that will best meet the requirements of the environments and processes they are investigating, as well as to recognize the merits of using more than one approach. This report is designed to make the reader aware of the breadth of approaches available for the study of the exchange between surface and ground water. To accomplish this, the report is divided into four chapters. Chapter 1 describes many well-documented approaches for defining the flow between surface and ground waters. Subsequent chapters provide an in-depth presentation of particular methods. Chapter 2 focuses on three of the most commonly used methods to either calculate or directly measure flow of water between surface-water bodies and the ground-water domain: (1) measurement of water levels in well networks in combination with measurement of water level in nearby surface water to determine water-level gradients and flow; (2) use of portable piezometers (wells) or hydraulic potentiomanometers to measure hydraulic gradients; and (3) use of seepage meters to measure flow directly. Chapter 3 focuses on describing the techniques involved in conducting water-tracer tests using fluorescent dyes, a method commonly used in the hydrogeologic investigation and characterization of karst aquifers, and in the study of water fluxes in karst terranes. Chapter 4 focuses on heat as a tracer in hydrological investigations of the near-surface environment.

Techniques and Methods↗
USGS2003

Determining temperature and thermal properties for heat-based studies of surface-water ground-water interactions: Appendix A of Heat as a tool for studying the movement of ground water near streams (Cir1260)

Advances in electronics leading to improved sensor technologies, large-scale circuit integration, and attendant miniaturization have created new opportunities to use heat as a tracer of subsurface flow. Because nature provides abundant thermal forcing at the land surface, heat is particularly useful in studying stream-groundwater interactions. This appendix describes methods for obtaining the thermal data needed in heat-based investigations of shallow subsurface flow.

Report↗