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USGS2013

Organic waste compounds in streams: Occurrence and aquatic toxicity in different stream compartments, flow regimes, and land uses in southeast Wisconsin, 2006–9

An assessment of organic chemicals and aquatic toxicity in streams located near Milwaukee, Wisconsin, indicated high potential for adverse impacts on aquatic organisms that could be related to organic waste compounds (OWCs). OWCs used in agriculture, industry, and households make their way into surface waters through runoff, leaking septic-conveyance systems, regulated and unregulated discharges, and combined sewage overflows, among other sources. Many of these compounds are toxic at elevated concentrations and (or) known to have endocrine-disrupting potential, and often they occur as complex mixtures. There is still much to be learned about the chronic exposure effects of these compounds on aquatic populations. During 2006–9, the U.S. Geological Survey, in cooperation with the Milwaukee Metropolitan Sewerage District (MMSD), conducted a study to determine the occurrence and potential toxicity of OWCs in different stream compartments and flow regimes for streams in the Milwaukee area. Samples were collected at 17 sites and analyzed for a suite of 69 OWCs. Three types of stream compartments were represented: water column, streambed pore water, and streambed sediment. Water-column samples were subdivided by flow regime into stormflow and base-flow samples. One or more compounds were detected in all 196 samples collected, and 64 of the 69 compounds were detected at least once. Base-flow samples had the lowest detection rates, with a median of 12 compounds detected per sample. Median detection rates for stormflow, pore-water, and sediment samples were more than double that of base-flow samples. Compounds with the highest detection rates include polycyclic aromatic hydrocarbons (PAHs), insecticides, herbicides, and dyes/pigments. Elevated occurrence and concentrations of some compounds were detected in samples from urban sites, as compared with more rural sites, especially during stormflow conditions. These include the PAHs and the domestic waste-water-indicator compounds, among others. Urban runoff and storm-related leaks of sanitary sewers and (or) septic systems may be important sources of these and other compounds to the streams. The Kinnickinnic River, a highly urbanized site, had the highest detection rates and concentrations of compounds of all the sampled sites. The Milwaukee River near Cedarburg—one of the least urban sites—and the Outer Milwaukee Harbor site had the lowest detection rates and concentrations. Aquatic-toxicity benchmarks were exceeded for 12 of the 25 compounds with known benchmarks. The compounds with the greatest benchmark exceedances were the PAHs, both in terms of exceedance frequency (up to 93 percent for some compounds in sediment samples) and magnitude (concentrations up to 1,024 times greater than the benchmark value). Other compounds with toxicity-benchmark exceedances include Bis(2-ethylhexyl) phthalate (a plasticizer), 2-Methylnapthalene (a component of fuel and oil), phenol (an antimicrobial disinfectant with diverse uses), and 4-Nonylphenol (sum of all isomers; a detergent metabolite, among other uses). Analyzed as a mixture, the suite of PAH compounds were found to be potentially toxic for most non-base-flow samples. Bioassay tests were conducted on samples from 14 streams: Ceriodaphnia dubia in base-flow samples, Ceriodaphnia dubia and Hyallela azteca in pore-water samples, and Hyallela azteca and Chironomus tentans in sediment samples. The greatest adverse effect was observed in tests with Chironomus tentans from sediment samples. The weight of Chironomus tentans after exposure to sediments decreased with increased OWC concentrations. This was most evident in the relation between PAH results and Chironomus tentans bioassay results for the majority of samples; however, solvents and flame retardants appeared to be important for one site each. These results for PAHs were consistent with assessment of PAH potency factors for sediment, indicating that PAHs were likely to have adverse effects on aquatic organisms in many of the streams studied.

Wisconsin↗

USGS2022

Hydrogeology and simulation of groundwater flow in the Lucerne Valley groundwater basin, California

The Lucerne Valley is in the southwestern part of the Mojave Desert and is about 75 miles northeast of Los Angeles, California. The Lucerne Valley groundwater basin encompasses about 230 square miles and is separated from the Upper Mojave Valley groundwater basin by splays of the Helendale Fault. Since its settlement, groundwater has been the primary source of water for agricultural, industrial, municipal, and domestic uses. Groundwater withdrawal from pumping has exceeded the amount of water recharged to the basin, causing groundwater declines of more than 100 feet between 1917 and 2016 in the center of the basin. The continued withdrawal has resulted in an increase in pumping costs, reduced well efficiency, and land subsidence near Lucerne Lake. Although the volume of pumping has declined in recent years, there is concern that new agricultural growth and limits on imported water will continue to strain the sustainability of the groundwater system. To address these concerns, the U.S. Geological Survey entered into a cooperative agreement with the Mojave Water Agency to develop a better understanding of the Lucerne Valley hydrogeologic system and provide tools to help evaluate and manage the effects of future development in the Lucerne Valley. The objectives of this study were to (1) improve the understanding of the aquifer system, (2) improve the understanding of subsidence in the basin, and (3) incorporate the understanding into a groundwater-flow model that can be used to help manage the groundwater resources in the Lucerne Valley. The model developed for this study covers the period of 1942–2016 and can help evaluate various proposed water-management scenarios during different climatic and hydrologic conditions. The aquifer system consists of a shallow aquifer, a confining unit, and middle and lower aquifers. These layered water-bearing units were identified based on geologic units of the mostly unconsolidated sediments and hydrologic properties. These alluvial deposits consist of clay, silt, sand, and gravel; some places also contain clay and silty clay lacustrine deposits. Several faults act, at least in part, as barriers to groundwater flow on the eastern, southern, and western edges of the basin. Present-day natural recharge is primarily from the infiltration of runoff from the San Bernardino Mountains to the south; however, stable and radioactive isotopes show that groundwater from the middle of the Lucerne Valley was older than about 10,000 years and probably was recharged as infiltration from streams draining the mountains in the Mojave Desert to the north, which probably does not occur under present-day climatic conditions. The annual average natural recharge for 1942–2016, estimated by a Basin Characterization Model, was about 635 acre-feet per year; the average amount of treated wastewater effluent transferred to the Lucerne Valley for artificial recharge annually ranged from about 1,500 to 4,000 acre-feet per year during 1980–2016. Pumpage estimates for 1942–2016 ranged from about 3,000 acre-feet in 1942 to about 18,300 acre-feet in 1984. The total cumulative amount of groundwater removed from the basin by pumping between 1942 and 2016 was estimated to be about 700,000 acre-feet, which was about 10 times greater than the cumulative amount of recharge to the entire Lucerne Valley groundwater basin. Before groundwater development, the direction of groundwater flow was from the southern part of the basin northward to discharge areas near Lucerne Lake, where it discharged through springs along the Helendale Fault and by evapotranspiration. Since the early 1900s, groundwater-level declines have mostly eliminated the areas where natural discharge occurred and exceeded 100 feet in the middle of the basin between the early 1950s and mid-1990s, and as much as 25 feet near the margins from about the mid-1950s to 2000s. A decrease in the rate of pumping after the mid-1990s lessened the hydraulic stress on the middle and lower aquifers and enabled hydraulic heads in the middle of the basin to recover slightly as groundwater near the margins of the basin moved toward the pumping depression. Although trends in groundwater levels in the center of the basin have reversed since the mid-1990s, levels at the basin margins continue to decline as the movement of groundwater from the margins fills the pumping depression and gradually flattens the groundwater table throughout the basin. The long-term extraction of groundwater and associated dewatering of the fine-grained sediments present within the aquifer system has resulted in aquifer compaction and consequently land subsidence, primarily near Lucerne Lake. Analysis of interferometric synthetic aperture radar data shows that almost 11 inches of land subsidence has occurred south of Lucerne Lake between April 1992 and November 2009; less subsidence occurred elsewhere in the basin during this period. This differential land subsidence has caused fissures and cracks in the ground surface, which have buckled the pavement and undercut roads in several locations. The Lucerne Valley Hydrologic Model was developed using the finite-difference groundwater modeling software One Water Hydrologic Model to represent the hydrologic conditions and stresses during 1942–2016. The model has a uniform grid of approximately 92 acres per cell (2,000 feet by 2,000 feet) and has four layers representing the water-bearing units. The results from the calibrated model simulations indicated that groundwater pumpage exceeded recharge, resulting in an estimated net cumulative depletion of groundwater storage (discharge minus recharge) of about 465,000 acre-feet from 1942 to 2016. The model simulated as much as 7.5 feet (90 inches; 2,286 millimeters) of aquifer compaction, which indicates the extensive fine-grained deposits and measured subsidence near Lucerne Lake.

California↗

USGS1998

Effects of farming systems on ground-water quality at the management systems evaluation area near Princeton, Minnesota, 1991-95

Ground-water quality in an unconfined sand and gravel aquifer was monitored during 1991-95 at the Minnesota Management Systems Evaluation Area (MSEA) near Princeton, Minnesota. The objectives of the study were to: (1) describe the effects of three farming systems on groundwater quality, and (2) evaluate the factors affecting ground-water quality and transport of agricultural chemicals at the site. Concentrations of nitrate nitrogen (nitrate-N) in the upper 1 meter (m) of the saturated zone were greatest beneath the two cropped areas having a potato-sweet corn annual rotation (median concentrations of 23 and 22 mg/L). Concentrations of nitrate-N were least beneath a cropped area having a field cornsoybean annual rotation (median of 14 mg/L); another cropped area having the field corn-soybean rotation had similar nitrate-N concentrations to those beneath a cropped area having field corn in consecutive years (continuous corn)(medians of 17 mg/L). Concentrations of atrazine plus metabolites de-ethylatrazine (DEA) and de-isopropylatrazine (DIA), atrazine plus metabolites, were significantly greater during 1994-95 than during 1992- 93 beneath all cropped areas in the upper 1 m of the saturated zone. Concentrations of atrazine plus metabolites during 1994-95 were greatest beneath the continuous corn (median of 1.07 ( μ g/L), intermediate beneath one cropped area with the potato-sweet corn rotation (median of 0.37 μ g/L), and least beneath the other cropped area with the potato-sweet corn rotation, the field corn-soybean rotation, and background areas (medians ranging from 0.11 to 0.21 μ g/L), for which concentrations were not significantly different. Concentrations of atrazine plus metabolites during 1992-93 were mostly similar beneath the different cropped areas and background areas. DEA was the predominant atrazine-metabolite detected in ground water; the average DEA to atrazine ratio was 8.0. The herbicides metribuzin, alachlor, and metolachlor were rarely detected in ground water at trace levels and could not be linked to the MSEA farming systems, with the exception of metribuzin detections during 1993-94 at concentrations of 0.14-1.24 ( μ g/L beneath one cropped area where metribuzin was applied to potatoes. Peak concentrations of chloride and bromide tracers were usually detected in the upper 2 m of the saturated zone 11 to 19 months after application. Peak concentrations of nitrate-N and atrazine plus metabolites were usually detected about 13 to 27 months and 2 years after application, respectively. The estimated proportion of applied nitrogen that reached ground water ranged from about 13 to 50 percent with an average of 30 percent. Differences in the concentrations of nitrate-N in ground water between different cropped areas were related to varying nitrogen application rates, timing of nitrogen application, timing of recharge in relation to crop rotation, and differences in nitrogen uptake by crops. In order of importance, plant uptake and leaching to ground water likely account for most of the nitrogen applied. Denitrification likely is an important mechanism affecting nitrate-N concentrations at depths greater than 2 m below the water table. The proportion of applied atrazine in ground water, detected as atrazine or its metabolites, ranged from 0 to about 1 percent with an average of 0.37 percent. The small proportion of applied atrazine detected in ground water indicates that atrazine was predominantly affected by processes occurring in the soil such as adsorption and degradation. Concentrations of atrazine plus metabolites were related to application rates.

Minnesota↗

USGS1993

Numerical simulation of ground-water flow in the central part of the western San Joaquin Valley, California

The occurrence of selenium in agricultural drain water in the central part of the western San Joaquin Valley, California, has focused concern on strategies for managing shallow, saline ground water. To assess alternatives to agricultural drains, a three-dimensional, finite-difference numerical model of the regional groundwater flow system was developed. This report documents the mathematical approach used to model the flow system, the data base on which the model is based, and the methods used to calibrate the model. The 550-square-mile study area includes parts of the Panoche Creek alluvial fan and parts of the Little Panoche Creek and Cantua Creek alluvial fans. The model simulates transient flow in the semiconfined and confined zones above and below the Corcoran Clay Member of the Tulare Formation of Pleistocene age. The model incorporates areally distributed ground-water recharge, areally and vertically distributed pumping, regional-collector drains in the Wesdands Water District (operative from 1980 to 1985), on-farm drains in parts of the Panoche, Broadview, and Firebaugh Water Districts, and bare-soil evaporation (which occurs if the water table is within 7 feet of land surface). The model also incorporates texture-based estimates of hydraulic conductivity, where texture is defined as the fraction of coarse-grained deposits present in a given subsurface interval. The numerical model was developed using hydrologic data from 1972 to 1988. Most of the parameters incorporated into the model were evaluated independently of the model, including system geometry, the distribution of texture, the altitudes of the water table and potentiometric surface of the confined zone in 1972 (initial condition), the hydraulic conductivity of coarse-grained deposits derived from the Coast Ranges, the hydraulic conductivity of coarse-grained deposits derived from the Sierra Nevada, specific storage, recharge, pumping, and parameters needed to incorporate drains and bare-soil evaporation. Four parameters were calibration variables: the hydraulic conductivity of fine-grained deposits in the semiconfined zone, the hydraulic conductivity of the Corcoran Clay Member, specific yield, and the transmissivity of the confined zone. The model was calibrated in two phases. In the first phase, a steady-state model of the ground-water flow system in 1984 was used to constrain the relation between the hydraulic conductivity of fine-grained deposits in the semiconfined zone and the hydraulic conductivity of the Corcoran Clay Member, thus reducing the number of independent variables from four to three. In the second phase of calibration, the change in altitude of the water table from 1972 to 1984, the change in altitude of the potentiometric surface of the confined zone from 1972 to 1984, and the number of model cells subject to bare-soil evaporation from 1972 to 1988 were used to evaluate the remaining three variables. The calibrated model reproduces the average change in water-table altitude (1972-84) to within 0.4 foot (average measured change 11.5 feet) and the average change in confined zone head (1972- 84) to within 19 feet (average measured change 120 feet). The simulated time-series record of the total number of model cells subject to bare-soil evaporation (each cell is 1 mile square) is within the range of the measured data. The measured values are at a minimum in October and a maximum in July. The October values ranged from 103 in 1972 to 132 in 1984 (the drains were closed in 1985) to 151 in 1988. The July values ranged from 144 in 1973 to 198 in 1984, to 204 in 1988. The simulated values ranged from 103 in 1972 to 161 in 1984, to 208 in 1988.

Water Supply Paper↗

USGS2011

Groundwater quality in the Monterey Bay and Salinas Valley groundwater basins, California

The Monterey-Salinas study unit is nearly 1,000 square miles and consists of the Santa Cruz Purisima Formation Highlands, Felton Area, Scotts Valley, Soquel Valley, West Santa Cruz Terrace, Salinas Valley, Pajaro Valley, and Carmel Valley groundwater basins (California Department of Water Resources, 2003; Kulongski and Belitz, 2011). These basins were grouped into four study areas based primarily on geography. Groundwater basins in the north were grouped into the Santa Cruz study area, and those to the south were grouped into the Monterey Bay, the Salinas Valley, and the Paso Robles study areas (Kulongoski and others, 2007). The study unit has warm, dry summers and cool, moist winters. Average annual rainfall ranges from 31 inches in Santa Cruz in the north to 13 inches in Paso Robles in the south. The study areas are drained by several rivers and their principal tributaries: the Salinas, Pajaro, and Carmel Rivers, and San Lorenzo Creek. The Salinas Valley is a large intermontane valley that extends southeastward from Monterey Bay to Paso Robles. It has been filled, up to a thickness of 2,000 feet, with Tertiary and Quaternary marine and terrestrial sediments that overlie granitic basement. The Miocene-age Monterey Formation and Pliocene- to Pleistocene-age Paso Robles Formation, and Pleistocene to Holocene-age alluvium contain freshwater used for supply. The primary aquifers in the study unit are defined as those parts of the aquifers corresponding to the perforated intervals of wells listed in the California Department of Public Health database. Public-supply wells are typically drilled to depths of 200 to 650 feet, consist of solid casing from the land surface to depths of about 175 to 500 feet, and are perforated below the solid casing. Water quality in the primary aquifers may differ from that in the shallower and deeper parts of the aquifer system. Groundwater movement is generally from the southern part of the Salinas Valley north towards the Monterey Bay. Land use in the study unit is about 44 percent (%) natural (mostly grassland and forests), 43% agricultural, and 13% urban. The primary agricultural uses are row crops, pasture, hay, and vineyards. The largest urban areas are the cities of Santa Cruz, Watsonville, Monterey, Salinas, King City, and Paso Robles. Recharge to the groundwater system is primarily from stream-channel infiltration from the major rivers and their tributaries, and from infiltration of water from precipitation and irrigation. The primary sources of discharge are water pumped for irrigation and municipal supply, evaporation, and discharge to streams.

Fact Sheet↗

USGS1997

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↗

USGS2010

Groundwater Quality in the Central Eastside San Joaquin Valley, California

The Central Eastside study unit is located in California's San Joaquin Valley. The 1,695 square mile study unit includes three groundwater subbasins: Modesto, Turlock, and Merced (California Department of Water Resources, 2003). The primary water-bearing units consist of discontinuous lenses of gravel, sand, silt, and clay, which are derived largely from the Sierra Nevada Mountains to the east. Public-supply wells provide most of the drinking water supply in the Central Eastside. Consequently, the primary aquifer in the Central Eastside study unit is defined as that part of the aquifer corresponding to the perforated interval of wells listed in the California Department of Public Health database. Public-supply wells are typically drilled to depths of 200 to 350 feet, consist of solid casing from the land surface to a depth of about 100 to 200 feet, and they are perforated below the solid casing. Water quality in the shallower and deeper parts of the aquifer system may differ from that in the primary aquifer. The Central Eastside study unit has hot and dry summers and cool, moist, winters. Average annual rainfall ranges from 11 to 15 inches. The Stanislaus, Tuolumne, and Merced Rivers, with headwaters in the Sierra Nevada Mountains, are the primary streams traversing the study unit. Land use in the study unit is approximately 59 percent (%) agricultural, 34% natural (primarily grassland), and 7% urban. The primary crops are almonds, walnuts, peaches, grapes, grain, corn, and alfalfa. The largest urban areas (2003 population in parentheses) are the cities of Modesto (206,872), Turlock (63,467), and Merced (69,512). Municipal water use accounts for about 5% of the total water use in the Central Eastside study unit, with the remainder used for irrigated agriculture. Groundwater accounts for about 75% of the municipal supply, and surface water accounts for about 25%. Recharge to the groundwater flow system is primarily from percolation of irrigation return, precipitation, seepage from reservoirs and rivers, and urban return (Burow and others, 2004; Phillips and others, 2007). The primary sources of discharge are pumping for irrigation and municipal supply, evaporation from areas with a shallow depth to water, and discharge to streams. Recharge at shallow depths and pumping from wells at greater depths causes downward movement of groundwater in the aquifer in the Central Eastside. This vertical movement of water has the potential to carry chemical constituents from shallow depths to the greater depths where supply wells commonly are perforated.

Fact Sheet↗

USGS2015

Suburban groundwater quality as influenced by turfgrass and septic sources, Delmarva Peninsula, USA

Suburban land use is expanding in many parts of the United States and there is a need to better understand the potential water-quality impacts of this change. This study characterized groundwater quality in a sandy, water-table aquifer influenced by suburban development and compared the results to known patterns in water chemistry associated with natural, background conditions and agricultural effects. Samples for nutrients, major ions, and isotopes of N and O in NO 3 − were collected in 2011 beneath turfgrass from 29 shallow wells (median depth 3.7 m) and from 18 deeper wells (median depth 16.9 m) in a long-term suburban development. Nitrate (as N) concentrations in groundwater beneath turfgrass were highly variable (0.02–22.3 mg L −1 ) with a median of 2.7 mg L −1 , which is higher than natural water chemistry (>0.4 mg L −1 ; Na + –Cl − –HCO 3 − water type), but significantly lower than concentrations beneath a nearby agricultural area (median 16.9 mg L −1 ; p < .0001). Dissolved Fe concentrations in shallow suburban groundwater, attributed to chelated Fe in turfgrass fertilizers, were significantly higher ( p < .005) than concentrations from the agricultural site, although a Ca 2+ –Mg 2+ –Cl − –NO 3 − water type was dominant in both areas. A Na + –Cl − –NO 3 − water type indicated a septic-system source for nitrate in deep suburban groundwater (0.06–6.0 mg L −1 ; median 1.5 mg L −1 ). Isotopic data indicated denitrification; however, geochemical techniques were more helpful in identifying nitrate sources. Results indicate that suburban expansion into agricultural areas may significantly decrease overall nitrate concentrations in groundwater, but excessive turfgrass fertilization could result in localized contamination.

Delaware↗

USGS1993

Effects of well discharges on hydraulic heads in and spring discharges from the geothermal aquifer system in the Bruneau area, Owyhee County, southwestern Idaho

Demand for ground water in the 600- square-mile Bruneau study area has increased since 1954 because of agricultural development. Declining flow at Indian Bathtub Spring is adversely affecting a unique species of snail that inhabits the spring. The Bruneau study area is underlain by sedimentary and volcanic rocks that form a regional geothermal aquifer. Sedimentary rocks range in thickness from zero in the southern part of the study area to more than 3,000 feet in the northeastern corner. Volcanic rocks underlie the entire study area and extend southward to the Jarbidge Mountains. In the central part of the study area, the volcanic rocks are probably 2,000 to 3,000 feet thick. For purposes of study, the regional geothermal aquifer system was divided into sedimentary- and volcanic-rock aquifers. Ground water flows northward through the volcanic-rock aquifer to the sedimentary- rock aquifer, from areas of recharge along the Jarbidge and Owyhee Mountains into the study area, where it is discharged as spring flow or leaves the study area as underflow. Prior to extensive ground-water development, about 10,100 acre-feet was discharged by springs. Ground-water discharge from wells began in the late 1890's. From the 1890's through 1951, annual discharge was less than 10,000 acre-feet. From 1952 to 1978, annual discharge increased to about 40,600 acre-feet. During 1978-91, well discharge declined from the maximum of 49,900 acre-feet in 1981 to 34,700 acre-feet in 1991. Through 1991, nearly 1,400,000 acre-feet of ground water discharged from wells; about 546,000 acre-feet discharged from 1978 through 1991. Most pumped water is from the volcanic-rock aquifer. Ground-water development since the mid-1890's locally has modified the direction of water movement in both the sedimentary- and volcanic-rock aquifers. In 1989, ground water moved toward four cones of depression created by pumping two in the northern part of the study area are in the sedimentary-rock aquifer, two in the southern part are in the volcanic-rock aquifer. Pumping has caused hydraulic heads in the volcanic-rock aquifer to decline more than 30 feet in much of the area and at least 70 feet in one well. About 1 mile from Indian Bathtub Spring, the water level in one well declined about 10 feet during 1979-92, or about 0.7 feet per year. Within the past 25 years, discharge from monitored springs along Hot Creek and the Bruneau River has declined, most notably from Indian Bathtub Spring. Discharge from Indian Bathtub Spring in 1964 was about 2,400 gallons per minute, and by the summer of 1989, discharge was zero. Discharge began to decline in the mid-1960's when the rate of increase in pumpage accelerated. In contrast, discharge from Pence Hot Spring has ranged from about 700 gallons per minute to about 1,100 gallons per minute. Changes in discharge from monitored springs corresponded with changes in hydraulic head, which fluctuates seasonally, and are substantially less in late summer than in the spring. A hydraulic head/spring discharge relation was developed for two sites at Indian Bathtub Spring and a nearby test hole. The relation for Indian Bathtub Spring indicated that a spring discharge of 2,400 gallons per minute would relate to a hydraulic head of about 2,708 feet at the spring, which is about 34 feet higher than the head at zero spring discharge.

Idaho↗

USGS2004

Aqueous photolysis of niclosamide

The photodegradation of [ 14 C]niclosamide was studied in sterile, pH 5, 7, and 9 buffered aqueous solutions under artificial sunlight at 25.0 ± 1.0 °C. Photolysis in pH 5 buffer is 4.3 times faster than in pH 9 buffer and 1.5 times faster than in pH 7 buffer. In the dark controls, niclosamide degraded only in the pH 5 buffer. After 360 h of continuous irradiation in pH 9 buffer, the chromatographic pattern of the degradates was the same regardless of which ring contained the radiolabel. An HPLC method was developed that confirmed these degradates to be carbon dioxide and two- and four-carbon aliphatic acids formed by cleavage of both aromatic rings. Carbon dioxide was the major degradate, comprising ∼40% of the initial radioactivity in the 360 h samples from both labels. The other degradates formed were oxalic acid, maleic acid, glyoxylic acid, and glyoxal. In addition, in the chloronitroaniline-labeled irradiated test solution, 2-chloro-4-nitroaniline was observed and identified after 48 h of irradiation but was not detected thereafter. No other aromatic compounds were isolated or observed in either labeled test system.

Journal of Agricultural and Food Chemistry↗

USGS2011

Regional groundwater-flow model of the Redwall-Muav, Coconino, and alluvial basin aquifer systems of northern and central Arizona

A numerical flow model (MODFLOW) of the groundwater flow system in the primary aquifers in northern Arizona was developed to simulate interactions between the aquifers, perennial streams, and springs for predevelopment and transient conditions during 1910 through 2005. Simulated aquifers include the Redwall-Muav, Coconino, and basin-fill aquifers. Perennial stream reaches and springs that derive base flow from the aquifers were simulated, including the Colorado River, Little Colorado River, Salt River, Verde River, and perennial reaches of tributary streams. Simulated major springs include Blue Spring, Del Rio Springs, Havasu Springs, Verde River headwater springs, several springs that discharge adjacent to major Verde River tributaries, and many springs that discharge to the Colorado River. Estimates of aquifer hydraulic properties and groundwater budgets were developed from published reports and groundwater-flow models. Spatial extents of aquifers and confining units were developed from geologic data, geophysical models, a groundwater-flow model for the Prescott Active Management Area, drill logs, geologic logs, and geophysical logs. Spatial and temporal distributions of natural recharge were developed by using a water-balance model that estimates recharge from direct infiltration. Additional natural recharge from ephemeral channel infiltration was simulated in alluvial basins. Recharge at wastewater treatment facilities and incidental recharge at agricultural fields and golf courses were also simulated. Estimates of predevelopment rates of groundwater discharge to streams, springs, and evapotranspiration by phreatophytes were derived from previous reports and on the basis of streamflow records at gages. Annual estimates of groundwater withdrawals for agriculture, municipal, industrial, and domestic uses were developed from several sources, including reported withdrawals for nonexempt wells, estimated crop requirements for agricultural wells, and estimated per capita water use for exempt wells. Accuracy of the simulated groundwater-flow system was evaluated by using observational control from water levels in wells, estimates of base flow from streamflow records, and estimates of spring discharge. Major results from the simulations include the importance of variations in recharge rates throughout the study area and recharge along ephemeral and losing stream reaches in alluvial basins. Insights about the groundwater-flow systems in individual basins include the hydrologic influence of geologic structures in some areas and that stream-aquifer interactions along the lower part of the Little Colorado River are an effective control on water level distributions throughout the Little Colorado River Plateau basin. Better information on several aspects of the groundwater flow system are needed to reduce uncertainty of the simulated system. Many areas lack documentation of the response of the groundwater system to changes in withdrawals and recharge. Data needed to define groundwater flow between vertically adjacent water-bearing units is lacking in many areas. Distributions of recharge along losing stream reaches are poorly defined. Extents of aquifers and alluvial lithologies are poorly defined in parts of the Big Chino and Verde Valley sub-basins. Aquifer storage properties are poorly defined throughout most of the study area. Little data exist to define the hydrologic importance of geologic structures such as faults and fractures. Discharge of regional groundwater flow to the Verde River is difficult to identify in the Verde Valley sub-basin because of unknown contributions from deep percolation of excess surface water irrigation.

Scientific Investigations Report↗

USGS2001

Surface-geophysical characterization of ground-water systems of the Caloosahatchee River basin, southern Florida

The Caloosahatchee River Basin, located in southwestern Florida, includes about 1,200 square miles of land. The Caloosahatchee River receives water from Lake Okeechobee, runoff from the watershed, and seepage from the underlying ground-water systems; the river loses water through drainage to the Gulf of Mexico and withdrawals for public-water supply and agricultural and natural needs. Water-use demands in the Caloosahatchee River Basin have increased dramatically, and the Caloosahatchee could be further stressed if river water is used to accommodate restoration of the Everglades. Water managers and planners need to know how much water will be used within the river basin and how much water is contributed by Lake Okeechobee, runoff, and ground water. In this study, marine seismic-reflection and ground-penetrating radar techniques were used as a means to evaluate the potential for flow between the river and ground-water systems. Seven test coreholes were drilled to calibrate lithostratigraphic units, their stratal geometries, and estimated hydraulic conductivities to surface-geophysical profiles. A continuous marine seismic-reflection survey was conducted over the entire length of the Caloosahatchee River and extending into San Carlos Bay. Lithostratigraphic units that intersect the river bottom and their characteristic stratal geometries were identified. Results show that subhorizontal reflections assigned to the Tamiami Formation intersect the river bottom between Moore Haven and about 9 miles westward. Oblique and sigmoidal progradational reflections assigned to the upper Peace River Formation probably crop out at the floor of the river in the Ortona area between the western side of Lake Hicpochee and La Belle. These reflections image a regional-scale progradational deltaic depositional system containing quartz sands with low to moderate estimated hydraulic conductivities. In an approximate 6-mile length of the river between La Belle and Franklin Lock, deeper karstic collapse structures are postulated. These structures influence the geometries of parallel reflections that intersect the river channel. Here, reflections assigned to the Buckingham Limestone Member of the Tamiami Formation (a confining unit) and reflections assigned to the clastic zone of the sandstone aquifer likely crop out at the river bottom. Beneath these shallow reflections, relatively higher amplitude parallel reflections of the carbonate zone of the sandstone aquifer are well displayed in the seismic-reflection profiles. In San Carlos Bay, oblique progradational reflections assigned to the upper Peace River Formation are shown beneath the bay. Almost everywhere beneath the river, a diffuse ground-water flow system is in contact with the channel bottom. Ground-penetrating radar profiles of an area about 2 miles north of the depositional axis of the deltaic depositional system in the Ortona area show that progradational clinoforms imaged on seismic reflection profiles in the Caloosahatchee River are present within about 17 feet of the ground surface. Ground-penetrating radar profiles show southward dipping, oblique progradational reflections assigned to the upper Peace River Formation that are terminated at their tops by a toplapping or erosional discontinuity. These clinoformal reflections image clean quartz sand that is probably characterized by moderate hydraulic conductivity. This sand could be mapped using ground-penetrating radar methods.

Water-Resources Investigations Report↗

USGS2014

Documentation of a groundwater flow model (SJRRPGW) for the San Joaquin River Restoration Program study area, California

To better understand the potential effects of restoration flows on existing drainage problems, anticipated as a result of the San Joaquin River Restoration Program (SJRRP), the U.S. Geological Survey (USGS), in cooperation with the U.S. Bureau of Reclamation (Reclamation), developed a groundwater flow model (SJRRPGW) of the SJRRP study area that is within 5 miles of the San Joaquin River and adjacent bypass system from Friant Dam to the Merced River. The primary goal of the SJRRP is to reestablish the natural ecology of the river to a degree that restores salmon and other fish populations. Increased flows in the river, particularly during the spring salmon run, are a key component of the restoration effort. A potential consequence of these increased river flows is the exacerbation of existing irrigation drainage problems along a section of the river between Mendota and the confluence with the Merced River. Historically, this reach typically was underlain by a water table within 10 feet of the land surface, thus requiring careful irrigation management and (or) artificial drainage to maintain crop health. The SJRRPGW is designed to meet the short-term needs of the SJRRP; future versions of the model may incorporate potential enhancements, several of which are identified in this report. The SJRRPGW was constructed using the USGS groundwater flow model MODFLOW and was built on the framework of the USGS Central Valley Hydrologic Model (CVHM) within which the SJRRPGW model domain is embedded. The Farm Process (FMP2) was used to simulate the supply and demand components of irrigated agriculture. The Streamflow-Routing Package (SFR2) was used to simulate the streams and bypasses and their interaction with the aquifer system. The 1,300-square mile study area was subdivided into 0.25-mile by 0.25-mile cells. The sediment texture of the aquifer system, which was used to distribute hydraulic properties by model cell, was refined from that used in the CVHM to better represent the natural heterogeneity of aquifer-system materials within the model domain. In addition, the stream properties were updated from the CVHM to better simulate stream-aquifer interactions, and water-budget subregions were refined to better simulate agricultural water supply and demand. External boundary conditions were derived from the CVHM. The SJRRPGW was calibrated for April 1961 to September 2003 by using groundwater-level observations from 133 wells and streamflow observations from 19 streamgages. The model was calibrated using public-domain parameter estimation software (PEST) in a semi-automated manner. The simulated groundwater-level elevations and trends (including seasonal fluctuations) and surface-water flow magnitudes and trends reasonably matched observed data. The calibrated model is planned to be used to assess the potential effects of restoration flows on agricultural lands and the relative capabilities of proposed SJRRP actions to reduce these effects.

California↗

USGS2001

Landscape determinants of nonindigenous fish invasions

Much has been written about the influence of exotic or nonindigenous species on natural habitats and communities of organisms, but little is known of the physical or biological conditions that lead to successful invasion of native habitats and communities by exotics. We studied invasivity factors in headwater streams of the Susquehanna River West Branch, which drains portions of the northern Appalachian Plateau. A replicated (two major tributaries) 3 × 3 factorial design was used to determine landscape effects of size (stream order) and quality (land use) on abiotic (physical and chemical) and biotic (fish community structure and function) stream attributes. Seven (21%) of thirty-four fish species (brown trout, common carp, mimic shiner, bluegill, smallmouth bass, fantail darter, and banded darter) collected in the eighteen streams sampled were nonindigenous to the basin. Watershed size (stream orders 1, 3, and 5) significantly affected stream geomorphologic and habitat variables (gradient, width, depth, current velocity, diel water temperature, bank overhang, canopy cover, and woody debris density) but not water-quality variables, while land use in watersheds (conservation, mining, and agriculture) significantly affected measured water-quality variables (alkalinity and concentrations of manganese, calcium, chloride, nitrate, and total dissolved solids) but not stream physical or habitat quality. Both watershed size and land use affected fish-community variables such as presence of particular species, species density, species diversity, tolerance diversity, and mean fish size, but in both cases the effect was transparent to native-origin status of fish species. No relationships were found between occurrence of nonindigenous species in watersheds and trophic structure or functional diversity. Therefore, the hypothesis that reduced species diversity increases vulnerability to nonindigenous species was not supported. However, the spatial variation associated with both water-quality and habitat-quality factors was greater in streams with mixed (those with nonindigenous species) than with exclusively native assemblages. These findings suggest that the mechanism for successful invasion by nonindigenous or exotic species is through change in water or habitat quality associated with human or natural disturbances, such as agriculture and mining activities in watersheds. Biotic factors appear to play no or a lesser role in the invasibility of northern Appalachian lotic systems.

Biological Invasions↗

USGS2005

Evaluating water management strategies with the Systems Impact Assessment Model: SIAM version 4

Water from many of California's coastal rivers has been used for a wide variety of development ventures, including major agricultural diversions, hydropower generation, and contaminant assimilation from industry, agriculture and logging. Anthropogenic impacts often degrade water quality and decrease the quantity and quality of aquatic habitat. Reallocating streamflow away from uses that degrade water quality to uses that foster higher water quality is a critical step in restoring riverine habitat and the anadromous fish that rely on that habitat for a portion of their life cycle. Reallocation always brings with it the need to examine the economic efficiency of the proposed changes. If the dollar benefits of improving water quality are greater than the costs, the criterion of improving economic efficiency is satisfied, a fact that can be highly persuasive to decision makers contemplating reallocation. Previous related studies have examined nonmarket benefits of the Trinity River in northern California (Douglas and Taylor, 1998; Douglas and Taylor, 1999abc) but nothing of this kind had been done on the Klamath River, another system with numerous uses for and competition over water in times of drought. An economic survey is nearing completion for the mid- to lower Klamath River, including the Scott, Shasta, and Salmon Rivers, but excluding the Trinity River. This survey provides valuable insights about the magnitude of the benefits and nature of the costs of reallocating water from market uses to instream flows that improve water quality and assist in the recovery of Klamath River fish stocks. Preliminary survey results (Douglas and Johnson, 2002; Douglas and Sleeper, In Prep.) indicate that about 234,000 California, Oregon, and Nevada households made recreation trips to the Klamath River Basin 1997-1998 and that these users spent about $372 million on trip related expenditures. Clearly the prosperity of the region is closely linked to the demand for mid- and lower Klamath River Basin recreation trips. Further, respondents indicated that they would make roughly 36% more recreational trips per annum to the Klamath if the water quality and the fishery were restored to an unspoiled condition. Using two distinct types of survey data, these additional trips would yield benefits with a present value of approximately $9.6 billion (at a discount rate of 7.5%). Calculating costs to restore the fishery and raise water quality involved five major hypothetical restoration activities: (1) purchasing Klamath project farmland and environmentally sensitive forest lands, (2) allocating more water down the Trinity River to enhance the quantity and quality of Klamath flows below the confluence, (3) removing four mainstem dams along the Klamath River and losing their associated hydropower production, (4) eliminating all harvest of Klamath-Trinity fish stocks for a 12-year period including the acquisition of fishing rights from both tribal and commercial marine fishermen, and (5) operating all Klamath-Trinity fish hatcheries to restore self-reproducing stocks. In total, restoration costs were estimated to be about $1.7 to $2.3 billion. If the assumptions used in this study are valid, it is clear that the benefits ($9.6B) outweigh the costs of restoring water quality and the fishery. The apparent disparity between restoration benefits and costs for the Klamath River may suggest to some that water resources on the Klamath be reallocated to environmentally friendly nonmarket uses. The economic analysis rests in part on the information made available to the survey designers by the biological, hydrologic, and water quality data incorporated in The System Impact Assessment Model (SIAM). It is our hope that SIAM can be used to improve the river's water quality and fishery, and strengthen the important regional economy.

Open-File Report↗

USGS2005

Framework for regional synthesis of water-quality data for the glacial aquifer system in the United States

The glacial aquifer system is the largest principal aquifer in aerial extent and ground-water use for public supply in the United States. A principal aquifer is defined as a regionally extensive aquifer or aquifer system that has the potential to be used as a source of potable water (U.S. Geological Survey, 2003). Multiple aquifers often are grouped into large, extensive aquifer systems such as the glacial aquifer system. The glacial aquifer system is considered here to include all unconsolidated aquifers above bedrock north of the line of continental glaciation throughout the country (fig. 1). Total withdrawals from the glacial aquifer system were 3,560 million gallons per day in 2000, which constitutes almost 5 percent of total withdrawals from all aquifers in the United States (Maupin and Barber, 2005). Approximately 41 million people relied on the glacial aquifer for public supply and domestic use in 2000. The U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program began assessing the glacial aquifer system in 1991. The assessment of water-quality data on a regional scale, such as the glacial aquifer system, is coincident with the regional framework established by the Regional Aquifer-System Analysis Program (RASA) (Sun and others, 1997). From 1978 to 1995, the RASA Program systematically evaluated 25 of the Nation's most important groundwater systems including studies in the glacial aquifer system in the northeast, Midwest, and northern Midwest United States. The NAWQA Program is building on the work of the RASA Program to study the water quality of 16 of the most important ground-water systems (Lapham and others, 2005). Over 1,700 water-quality samples have been collected by the NAWQA Program from 1991 to 2004 to assess the glacial aquifer system. This large data set is unique in that the samples have been collected using a consistent sampling protocol, and multiple nested samples. The nested samples address the recently recharged shallow ground water, deeper water from principal aquifers often used for domestic supply, and source water used for public supplies within the glacial aquifer system. Information concerning the NAWQA Program including study unit boundaries is shown in figure 1 (Lapham and others, 2005). A framework for comparison of water quality across the glacial aquifer system has been developed based on two primary characteristics: intrinsic susceptibility and vulnerability. Intrinsic susceptibility, which is a measure of the ease at which water enters and moves through aquifer material, is a characteristic of the aquifer and overlying material and of the hydrologic conditions. Intrinsic susceptibility is independent of the chemical characteristics of the contaminant and its sources. In this way, intrinsic susceptibility assessments do not target specific natural or anthropogenic sources of contamination but instead consider only the physical factors affecting the flow of water to, and through the ground-water resource (Focazio and others, 2002). On a regional scale, intrinsic susceptibility is represented by the spatial distribution of fine- or coarse-grained material at the land surface, and the physical setting of the aquifer system. Vulnerability, which is a function of both intrinsic susceptibility and the proximity and characteristics of contaminant sources, includes consideration of features related to anthropogenic sources of contaminants, such as the character of the upgradient land use (for example, urban, agricultural, undeveloped, and others); as well as features related to natural sources of contaminants, such as the mineralogy of the aquifer material or the geochemical conditions within the aquifer system. The framework helps categorize this large region into areas of similar hydrogeologic characteristics for which water quality can be compared. The purpose of this report is to describe this framework and how it will be used for regional synthesis of water-quality da

Scientific Investigations Report↗

USGS1971

EROS — New observation vantage points and processes

The EROS Program objective is to utilize aircraft and spacecraft remote-sensing technology as complementary parts of integrated data collection, processing, and dissemination systems to support resources research and management functions of the Department of the Interior. The Program develops and coordinates research in the applications of new sensors for resources applications in cooperation with NASA. At present there are two major areas of activity: present there are two major areas of activity: The first is related to the Earth Resources Technology Satellite (ERTS). The second is a suite of projects designed to determine the applicability of new aerial and satellite sensing systems and techniques to geologic, geographic, hydrologic, and topographic mapping and for supporting natural resources management functions of the Department of the Interior. Programs with similar goals for agriculture and forestry, and for oceanography are being conducted in the Departments of Agriculture, Commerce, the Naval Oceanographic Office, and in a number of colleges and universities. The first satellite designed specifically for resources research and applications, ERTS-A, is to be launched in early 1972. It will be an unmanned satellite carrying three experimental systems: A three camera Return Beam Vidicon (RBV) system, a 4-band Multispectral Scanning (MSS) radiometer system, and a Data Collection System (DCS). The RBV cameras will photograph simultaneously and instantaneously areas of the earth 100 × 100 nautical miles - or 10,000 square nautical miles - in the blue-green (.475-.575mu m), the red (.580-.680mu m), and the near infrared (.690-.830mu m). The MSS will record three wavelength bands in the same general spectral range and the fourth band (8.0 mu m) will extend farther into the infrared...

Conference Paper↗

USGS2015

Public-supply water use in Kansas, 2013

This report, prepared by the U.S. Geological Survey in cooperation with the Kansas Department of Agriculture’s Division of Water Resources, presents derivative statistics of water used by Kansas public-supply systems in 2013. The published statistics from the previous 4 years (2009–12) are also shown with the 2013 statistics and are used to calculate a 5-year average. An overall Kansas average and regional averages also are calculated and presented.

Kansas↗