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USGS2010

Design of Cycle 3 of the National Water-Quality Assessment Program, 2013-2022: Part 1: Framework of Water-Quality Issues and Potential Approaches

In 1991, the U.S. Congress established the U.S. Geological Survey (USGS) National Water-Quality Assessment (NAWQA) Program to develop long-term, nationally consistent information on the quality of the Nation's streams and groundwater. Congress recognized the critical need for this information to support scientifically sound management, regulatory, and policy decisions concerning the increasingly stressed water resources of the Nation. The long-term goals of NAWQA are to: (1) assess the status of water-quality conditions in the United States, (2) evaluate long-term trends in water-quality conditions, and (3) link status and trends with an understanding of the natural and human factors that affect water quality. These goals are national in scale, include both surface water and groundwater, and include consideration of water quality in relation to both human uses and aquatic ecosystems. Since 1991, NAWQA assessments and findings have fostered and supported major improvements in the availability and use of unbiased scientific information for decisionmaking, resource management, and planning at all levels of government. These improvements have enabled agencies and stakeholders to cost-effectively address a wide range of water-quality issues related to natural and human influences on the quality of water and potential effects on aquatic ecosystems and human health (http://water.usgs.gov/nawqa/xrel.pdf). NAWQA, like all USGS programs, provides policy relevant information that serves as a scientific basis for decisionmaking related to resource management, protection, and restoration. The information is freely available to all levels of government, nongovernmental organizations, industry, academia, and the public, and is readily accessible on the NAWQA Web site and other diverse formats to serve the needs of the water-resource community at different technical levels. Water-quality conditions in streams and groundwater are described in more than 1,700 publications (available online at http://water.usgs.gov/nawqa/bib/), and are documented by more than 14 million data records representing about 7,600 stream sites, 8,100 wells, and 2,000 water-quality and ecological constituents that are available from the NAWQA data warehouse (http://infotrek.er.usgs.gov/traverse/f?p=NAWQA:HOME:0). The Program promotes collaboration and liaison with government officials, resource managers, industry representatives, and other stakeholders to increase the utility and relevance of NAWQA science to decisionmakers. As part of this effort, NAWQA supports integration of data from other organizations into NAWQA assessments, where appropriate and cost-effective, so that more comprehensive findings are available across geographic and temporal scales.

Open-File Report↗
USGS2011

Groundwater, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona—2009–10

The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of low precipitation in the arid climate of the Black Mesa area. Precipitation in the area is typically between 6 and 14 inches per year. The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from January 2009 to September 2010. The monitoring program includes measurements of (1) groundwater withdrawals, (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry. In 2009, total groundwater withdrawals were 4,230 acre-ft, industrial withdrawals were 1,390 acre-ft, and municipal withdrawals were 2,840 acre-ft. Total withdrawals during 2009 were about 42 percent less than total withdrawals in 2005 because of Peabody Western Coal Company's discontinued use of water in a coal slurry used for transporting coal. From 2008 to 2009 total withdrawals increased by 3 percent and industrial withdrawals increased by approximately 15 percent, but total municipal withdrawals decreased by 2 percent. From 2009 to 2010, annually measured water levels in the Black Mesa area declined in 7 of 16 wells that were available for comparison in the unconfined areas of the N aquifer, and the median change was 0.1 foot. Water levels declined in 12 of 18 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was -0.3 foot. From the prestress period (prior to 1965) to 2010, the median water-level change for 34 wells in both the confined and unconfined area was -13.9 feet. Also, from the prestress period to 2009, the median water-level changes were -0.8 foot for 16 wells measured in the unconfined areas and -38.7 feet for 18 wells measured in the confined area. Spring flow was measured at four springs in 2010. Flow fluctuated during the period of record, but a decreasing trend was apparent at Moenkopi School Spring and Pasture Canyon Spring. Discharge at Burro Spring and Unnamed Spring near Dennehotso has remained relatively constant since they were first measured in the 1980s. Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976 to 2009), Dinnebito Wash near Sand Springs 09401110 (1993 to 2009), Polacca Wash near Second Mesa 09400568 (1994 to 2009), and Pasture Canyon Springs 09401265 (2004 to 2009). Median winter flows (November through February) of each water year were used as an index of the amount of groundwater discharge at the above-named sites. For the period of record of each streamflow-gaging station, the median winter flows have generally remained constant, which suggests no change in groundwater discharge. In 2010, water samples collected from 11 wells and 4 springs in the Black Mesa area were analyzed for selected chemical constituents, and the results were compared with previous analyses. Concentrations of dissolved solids, chloride, and sulfate have varied at all 11 wells for the period of record, but neither increasing nor decreasing trends over time were found. Dissolved-solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 12 years of record at that site. Concentrations of dissolved solids, chloride, and sulfate at Pasture Canyon Spring have not varied much since the early 1980s, and there is no increasing or decreasing trend in those data. Concentrations of dissolved solids, chloride, and sulfate at Burro Spring and Unnamed Spring near Dennehotso have varied for the period of record, but there is no increasing or decreasing trend in the data.

Open-File Report↗
USGS2012

Groundwater, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona - 2010-2011

The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of low precipitation in the arid climate of the Black Mesa area. Precipitation in the area is typically between 6 to 14 inches per year. The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from January 2010 to September 2011. The monitoring program includes measurements of (1) groundwater withdrawals, (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry. In 2010, total groundwater withdrawals were 4,040 acre-ft, industrial withdrawals were 1,170 acre-ft, and municipal withdrawals were 2,870 acre-ft. Total withdrawals during 2010 were about 42 percent less than total withdrawals in 2005 because of Peabody Western Coal Company's discontinued use of water to transport coal in a slurry. From 2009 to 2010 total withdrawals decreased by 5 percent; industrial withdrawals decreased by approximately 16 percent, and total municipal withdrawals increased by 1 percent. From 2010 to 2011, annually measured water levels in the Black Mesa area declined in 7 of 15 wells that were available for comparison in the unconfined areas of the N aquifer, and the median change was 0.0 foot. Water levels declined in 11 of 18 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was -0.7 foot. From the prestress period (prior to 1965) to 2011, the median water-level change for 33 wells in both the confined and unconfined areas was -15.0 feet. Also, from the prestress period to 2011, the median water-level changes were -1.2 foot for 15 wells measured in the unconfined areas and -41.2 feet for 18 wells measured in the confined area. Spring flow was measured at three springs in 2011. Flow fluctuated during the period of record, but a decreasing trend was apparent at Moenkopi School Spring and Pasture Canyon Spring. Discharge at Burro Spring has remained relatively constant since it was first measured in the 1980s. Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976 to 2010), Dinnebito Wash near Sand Springs 09401110 (1993 to 2010), Polacca Wash near Second Mesa 09400568 (1994 to 2010), and Pasture Canyon Springs 09401265 (2004 to 2010). Median winter flows (November through February) of each water year were used as an index of the amount of groundwater discharge at the above-named sites. For the period of record of each streamflow-gaging station, the median winter flows have generally remained constant, which suggests no change in groundwater discharge. In 2011, water samples collected from 11 wells and 4 springs in the Black Mesa area were analyzed for selected chemical constituents, and the results were compared with previous analyses. Concentrations of dissolved solids, chloride, and sulfate have varied at all 11 wells for the period of record, but neither increasing nor decreasing trends over time were found. Dissolved-solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 12 years of record at that site. Concentrations of dissolved solids, chloride, and sulfate at Pasture Canyon Spring have not varied much since the early 1980s, and there is no increasing or decreasing trend in those data. Concentrations of dissolved solids, chloride, and sulfate at Burro Spring and Unnamed Spring near Dennehotso have varied for the period of record, but there is no increasing or decreasing trend in the data.

Arizona↗
USGS2012

Groundwater, surface-water, and water-chemistry data from C-aquifer monitoring program, northeastern Arizona, 2005-11

The C aquifer is a regionally extensive multiple-aquifer system supplying water for municipal, agricultural, and industrial use in northeastern Arizona, northwestern New Mexico, and southeastern Utah. An increase in groundwater withdrawals from the C aquifer coupled with ongoing drought conditions in the study area increase the potential for drawdown within the aquifer. A decrease in the water table and potentiometric surface of C aquifer is illustrated locally by the drying up of Obed Meadows, a natural peat deposit, and Hugo Meadows, a natural wetland, both south of Joseph City, Arizona. Continual increase in water use from the C aquifer, including a planned increase in pumpage by the City of Flagstaff, is justification for continued monitoring of the C-aquifer system in order to quantify physical and chemical responses to pumping stresses. Fifteen of the 35 C-aquifer wells analyzed had water-level data sufficient for percentage difference calculation for 2005–11. Change in water level as a percentage of the initial water-level measurement for these 15 wells ranged from about -0.2 to about -0.5 percent. For historical water-level data, changes in water levels were greatest around pumping centers, as indicated by a -97.0 feet (percentage difference of -16.5 percent) change over the period of record (1962–2005) for the Lake Mary 1 Well near Flagstaff, Arizona. In more rural areas of the C aquifer, water levels showed less change for both the temporal focus of this report (2005–11) and for historical values. Continuous records of surface-water discharge from 2005 to 2007 for three discontinued streamflow-gaging stations (Clear Creek near Winslow, AZ, 09399000; Clear Creek below McHood Lake near Winslow, AZ, 09399100; and Chevelon Creek near Winslow, AZ, 09398000) were tabulated. For the period of record, Clear Creek near Winslow, AZ, and Chevelon Creek near Winslow, AZ, showed seasonal discharge distributions indicative of natural streams in the southwestern United States. Clear Creek below McHood Lake near Winslow, AZ, showed discharge distribution indicative of perennial spring flow with little variation annually. Physical and chemical data collected during four baseflow investigations (summer 2005, summer 2006, summer 2008, and winter 2010) conducted on Clear Creek, Chevelon Creek, and a portion of the Little Colorado River were compiled and analyzed. Data from 7 sampling sites established on the Little Colorado River, 11 sites along Chevelon Creek, and 14 sites along Clear Creek were included. For the four baseflow investigations presented, a 2,000–3,000 microsiemens per centimeter increase in specific conductance was measured in Chevelon Creek from near its headwaters to the confluence with the Little Colorado River because of the contribution of highly conductive spring discharge. Clear Creek showed a less consistent pattern of increase in specific conductance with distance, but still exhibited changes on the order of 5,000 microsiemens per centimeter over just a few river miles. Water-chemistry data for selected wells and baseflow investigations sites are presented. No well samples analyzed exceeded the U.S. Environmental Protection Agency Maximum Contaminant Level standards for drinking water, but several samples exceeded Secondary Maximum Contaminant Level standards for chloride, fluoride, sulfate, iron, and total dissolved solids.

Arizona↗
USGS2014

Groundwater, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona: 2011-2012

The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of low precipitation in the arid climate of the Black Mesa area. Precipitation in the area typically is between 6 and 14 inches per year. The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from January 2011 to September 2012. The monitoring program includes measurements of (1) groundwater withdrawals, (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry. In 2011, total groundwater withdrawals were 4,480 acre-ft, industrial withdrawals were 1,390 acre-ft, and municipal withdrawals were 3,090 acre-ft. Total withdrawals during 2011 were about 39 percent less than total withdrawals in 2005 because of Peabody Western Coal Company’s discontinued use of water to transport coal in a slurry. From 2010 to 2011 total withdrawals increased by 11 percent; industrial withdrawals increased by approximately 19 percent, and total municipal withdrawals increased by 8 percent. From 2011 to 2012, annually measured water levels in the Black Mesa area declined in 8 of 15 wells that were available for comparison in the unconfined areas of the N aquifer, and the median change was -0.1 feet. Water levels declined in 9 of 18 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was 0.0 feet. From the prestress period (prior to 1965) to 2012, the median water-level change for 34 wells in both the confined and unconfined areas was -13.4 feet; the median water-level changes were -2.1 feet for 16 wells measured in the unconfined areas and -39.1 feet for 18 wells measured in the confined area. Spring flow was measured at four springs in 2012. Flow fluctuated during the period of record for Burro and Unnamed Spring near Dennehotso, but a decreasing trend was apparent at Moenkopi School Spring and Pasture Canyon Spring. Discharge at Burro Spring has remained relatively constant since it was first measured in the 1980s and discharge at Unnamed Spring near Dennehotso has fluctuated for the period of record. Trend analysis for discharge at Moenkopi and Pasture Canyon Springs yielded a slope significantly different from zero. Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976 to 2010), Dinnebito Wash near Sand Springs 09401110 (1993 to 2010), Polacca Wash near Second Mesa 09400568 (1994 to 2010), and Pasture Canyon Springs 09401265 (2004 to 2010). Median winter flows (November through February) of each water year were used as an index of the amount of groundwater discharge at the above-named sites. For the period of record of each streamflow-gaging station, the median winter flows have generally remained constant, and there are no significant statistical trends in groundwater discharge. In 2012, water samples collected from 10 wells and 4 springs in the Black Mesa area were analyzed for selected chemical constituents, and the results were compared with previous analyses. Concentrations of dissolved solids, chloride, and sulfate have varied at all 10 wells for the period of record, but neither increasing nor decreasing trends over time were found. Dissolved solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 12 years of record at that site. Concentrations of dissolved solids, chloride, and sulfate at Pasture Canyon Spring have not varied significantly since the early 1980s, and there is no increasing or decreasing trend in those data. Concentrations of dissolved solids, chloride, and sulfate at Burro Spring and Unnamed Spring near Dennehotso have varied for the period of record, but there is no increasing or decreasing trend in the data.

Arizona↗
USGS2015

Methodology for assessing quantities of water and proppant injection, and water production associated with development of continuous petroleum accumulations

The quantities of water and hydraulic fracturing proppant required for producing petroleum (oil, gas, and natural gas liquids) from continuous accumulations, and the quantities of water extracted during petroleum production, can be quantitatively assessed using a probabilistic approach. The water and proppant assessment methodology builds on the U.S. Geological Survey methodology for quantitative assessment of undiscovered technically recoverable petroleum resources in continuous accumulations. The U.S. Geological Survey assessment methodology for continuous petroleum accumulations includes fundamental concepts such as geologically defined assessment units, and probabilistic input values including well-drainage area, sweet- and non-sweet-spot areas, and success ratio within the untested area of each assessment unit. In addition to petroleum-related information, required inputs for the water and proppant assessment methodology include probabilistic estimates of per-well water usage for drilling, cementing, and hydraulic-fracture stimulation; the ratio of proppant to water for hydraulic fracturing; the percentage of hydraulic fracturing water that returns to the surface as flowback; and the ratio of produced water to petroleum over the productive life of each well. Water and proppant assessments combine information from recent or current petroleum assessments with water- and proppant-related input values for the assessment unit being studied, using Monte Carlo simulation, to yield probabilistic estimates of the volume of water for drilling, cementing, and hydraulic fracture stimulation; the quantity of proppant for hydraulic fracture stimulation; and the volumes of water produced as flowback shortly after well completion, and produced over the life of the well.

Open-File Report↗
USGS2016

Groundwater, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona—2012–2013

The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in northeastern Arizona because of continued water requirements for industrial and municipal use by a growing population and because of low precipitation in the arid climate of the Black Mesa area. Precipitation in the area typically is between 6 and 14 inches per year. The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from January 2012 to September 2013. The monitoring program includes measurements of (1) groundwater withdrawals, (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry. In calendar year 2012, total groundwater withdrawals were 4,010 acre-ft, industrial withdrawals were 1,370 acre-ft, and municipal withdrawals were 2,640 acre-ft. Total withdrawals during 2012 were about 45 percent less than total withdrawals in 2005 because of Peabody Western Coal Company’s discontinued use of water to transport coal in a coal slurry pipeline. From 2011 to 2012 total withdrawals decreased by 10 percent; industrial withdrawals decreased by approximately 1 percent, and total municipal withdrawals decreased by 15 percent. From 2012 to 2013, annually measured water levels in the Black Mesa area declined in 6 of 16 wells that were available for comparison in the unconfined areas of the N aquifer, and the median change was 0.8 feet. Water levels declined in 5 of 16 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was 0.3 feet. From the prestress period (prior to 1965) to 2013, the median water-level change for 34 wells in both the confined and unconfined areas was -13.5 feet; the median water-level changes were -0.8 feet for 16 wells measured in the unconfined areas and -51.0 feet for 16 wells measured in the confined area. Spring flow was measured at four springs in 2013; Burro, Unnamed Spring near Dennehotso, Moenkopi School, and Pasture Canyon Springs. Flow fluctuated during the period of record for Burro and Unnamed Springs near Dennehotso, but a decreasing trend was apparent at Moenkopi School Spring and Pasture Canyon Spring. Discharge at Burro Spring has remained relatively constant since it was first measured in the 1980s and discharge at Unnamed Spring near Dennehotso has fluctuated for the period of record at each spring. Trend analysis for discharge at Moenkopi School and Pasture Canyon Springs showed a decreasing trend. Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976 to 2013), Dinnebito Wash near Sand Springs 09401110 (1993 to 2013), Polacca Wash near Second Mesa 09400568 (1994 to 2013), and Pasture Canyon Springs 09401265 (2004 to 2013). Median winter flows (November through February) from these sites for each water year were used as an index of the amount of groundwater discharge. For the period of record of each streamflow-gaging station, the median winter flows have generally remained constant, which suggests no change in groundwater discharge. In 2013, water samples collected from 12 wells and 4 springs in the Black Mesa area were analyzed for selected chemical constituents, and the results were compared with previous analyses. Concentrations of dissolved solids, chloride, and sulfate have varied at all 12 wells for the period of record, but neither increasing nor decreasing trends over time were found. Dissolved solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 13 years of record at that site. Concentrations of dissolved solids, chloride, and sulfate at Pasture Canyon Spring have not varied significantly since the early 1980s. Concentrations of dissolved solids, chloride, and sulfate at Burro Spring and Unnamed Spring near Dennehotso have varied for the period of record with no increasing or decreasing trend in the data.

Arizona↗
USGS2016

Streamflow, water quality and constituent loads and yields, Scituate Reservoir drainage area, Rhode Island, water year 2014

Streamflow and concentrations of sodium and chloride estimated from records of specific conductance were used to calculate loads of sodium and chloride during water year (WY) 2014 (October 1, 2013, through September 30, 2014) for tributaries to the Scituate Reservoir, Rhode Island. Streamflow and water-quality data used in the study were collected by the U.S. Geological Survey and the Providence Water Supply Board in the cooperative study. Streamflow was measured or estimated by the U.S. Geological Survey following standard methods at 23 streamgages; 14 of these streamgages are equipped with instrumentation capable of continuously monitoring water level, specific conductance, and water temperature. Water-quality samples were collected at 37 sampling stations by the Providence Water Supply Board and at 14 continuous-record streamgages by the U.S. Geological Survey during WY 2014 as part of a long-term sampling program; all stations are in the Scituate Reservoir drainage area. Water-quality data collected by the Providence Water Supply Board are summarized by using values of central tendency and are used, in combination with measured (or estimated) streamflows, to calculate loads and yields (loads per unit area) of selected water-quality constituents for WY 2014. The largest tributary to the reservoir (the Ponaganset River, which was monitored by the U.S. Geological Survey) contributed a mean streamflow of 23 cubic feet per second to the reservoir during WY 2014. For the same time period, annual mean streamflows measured (or estimated) for the other monitoring stations in this study ranged from about 0.35 to about 14 cubic feet per second. Together, tributaries (equipped with instrumentation capable of continuously monitoring specific conductance) transported about 1,200,000 kilograms of sodium and 2,100,000 kilograms of chloride to the Scituate Reservoir during WY 2014; sodium and chloride yields for the tributaries ranged from 7,700 to 45,000 kilograms per year per square mile and from 12,000 to 75,000 kilograms per year per square mile, respectively. At the stations where water-quality samples were collected by the Providence Water Supply Board, the median of the median chloride concentrations was 24 milligrams per liter, median nitrite concentration was 0.002 milligrams per liter as nitrogen (N), median nitrate concentration was 0.01 milligrams per liter as N, median orthophosphate concentration was 0.07 milligrams per liter as phosphate, and median concentrations of total coliform bacteria and Escherichia coli were 320 and 20 colony forming units per 100 milliliters, respectively. The medians of the median daily loads (and yields) of chloride, nitrite, nitrate, orthophosphate, and total coliform and Escherichia coli bacteria were 62 kilograms per day (42 kilograms per day per square mile), 19 grams per day (6.1 grams per day per square mile), 79 grams per day (36 grams per day per square mile), 380 grams per day (150 grams per day per square mile), 13,000 million colony forming units per day (8,300 million colony forming units per day per square mile), and 1,000 million colony forming units per day (470 million colony forming units per day per square mile), respectively.

Rhode Island↗
USGS2018

Streamflow, water quality, and constituent loads and yields, Scituate Reservoir Drainage Area, Rhode Island, water year 2015

Streamflow and concentrations of sodium and chloride estimated from records of specific conductance were used to calculate loads of sodium and chloride during water year (WY) 2015 (October 1, 2014, through September 30, 2015) for tributaries to the Scituate Reservoir, Rhode Island. Streamflow and water-quality data used in the study were collected by the U.S. Geological Survey and the Providence Water Supply Board. Streamflow was measured or estimated by the U.S. Geological Survey following standard methods at 23 streamgages; 14 of these streamgages are equipped with instrumentation capable of continuously monitoring water level, specific conductance, and water temperature. Water-quality samples were collected at 36 sampling stations by the Providence Water Supply Board and at 14 continuous-record streamgages by the U.S. Geological Survey during WY 2015 as part of a long-term sampling program; all stations are in the Scituate Reservoir drainage area. Water-quality data collected by the Providence Water Supply Board are summarized by using values of central tendency and are used, in combination with measured (or estimated) streamflows, to calculate loads and yields (loads per unit area) of selected water-quality constituents for WY 2015. The largest tributary to the reservoir (the Ponaganset River, which was monitored by the U.S. Geological Survey) contributed a mean streamflow of 25 cubic feet per second to the reservoir during WY 2015. For the same time period, annual mean streamflows measured (or estimated) for the other monitoring stations in this study ranged from about 0.38 to about 14 cubic feet per second. Together, tributaries (equipped with instrumentation capable of continuously monitoring specific conductance) transported about 1,500,000 kilograms of sodium and 2,400,000 kilograms of chloride to the Scituate Reservoir during WY 2015; sodium and chloride yields for the tributaries ranged from 8,000 to 54,000 kilograms per square mile and from 12,000 to 91,000 kilograms per square mile, respectively. At the stations where water-quality samples were collected by the Providence Water Supply Board, the medians of the median concentrations were the following: for chloride, 29.5 milligrams per liter; for nitrite, 0.002 milligrams per liter as nitrogen; for nitrate, 0.05 milligrams per liter as nitrogen; for orthophosphate, 0.08 milligrams per liter as phosphate; and for total coliform bacteria and Escherichia coli , 440 and 20 colony forming units per 100 milliliters, respectively. The medians of the median daily loads (and yields) of chloride, nitrite, nitrate, orthophosphate, and total coliform and Escherichia coli bacteria were 170 kilograms per day (79 kilograms per day per square mile), 14 grams per day (5.2 grams per day per square mile), 670 grams per day (190 grams per day per square mile), 640 grams per day (210 grams per day per square mile), 18,000 million colony forming units per day (7,600 million colony forming units per day per square mile), and 1,200 million colony forming units per day (810 million colony forming units per day per square mile), respectively.

Rhode Island↗
USGS2018

Groundwater, surface-water, and water-chemistry data, Black Mesa area, northeastern Arizona—2015–2016

The Navajo (N) aquifer is an extensive aquifer and the primary source of groundwater in the 5,400-square-mile Black Mesa area in northeastern Arizona. Availability of water is an important issue in the Black Mesa area because of continued water requirements for industrial and municipal use by a growing population and because of the arid climate. Precipitation in the area typically ranges from less than 6 to more than 16 inches per year depending on location. The U.S. Geological Survey water-monitoring program in the Black Mesa area began in 1971 and provides information about the long-term effects of groundwater withdrawals from the N aquifer for industrial and municipal uses. This report presents results of data collected as part of the monitoring program in the Black Mesa area from November 2015 to December 2016. The monitoring program includes measurements of (1) groundwater withdrawals (pumping), (2) groundwater levels, (3) spring discharge, (4) surface-water discharge, and (5) groundwater chemistry. In calendar year 2016, total groundwater withdrawals were 3,540 acre-ft, industrial withdrawals were 1,090 acre-ft, and municipal withdrawals were 2,450 acre-ft. Total withdrawals during 2016 were about 52 percent less than total withdrawals in 2005 because of Peabody Western Coal Company’s discontinued use of water to transport coal in a coal slurry pipeline. From 2015 to 2016, annually measured water levels available for comparison in wells completed in the unconfined areas of the N aquifer within the Black Mesa area declined in 9 of 16 wells, and the median change was –0.1 feet. Water levels also declined in 8 of 16 wells measured in the confined area of the aquifer. The median change for the confined area of the aquifer was 0.0 feet. From the prestress period (prior to 1965) to 2016, the median water-level change for all 32 wells in both the confined and unconfined areas was –10.2 feet; the median water-level changes were –1.6 feet for the 16 wells measured in the unconfined areas and –36.1 feet for the 16 wells measured in the confined area. Spring flow was measured at four springs in 2016. Flow fluctuated during the period of record for Burro Spring and Pasture Canyon Spring, but a decreasing trend was statistically significant (p<0.05) at Moenkopi School Spring and Unnamed Spring near Dennehotso. Discharge at Burro Spring has remained relatively constant since it was first measured in the 1980s and discharge at Pasture Canyon Spring has fluctuated for the period of record. Continuous records of surface-water discharge in the Black Mesa area were collected from streamflow-gaging stations at the following sites: Moenkopi Wash at Moenkopi 09401260 (1976 to 2016), Dinnebito Wash near Sand Springs 09401110 (1993 to 2016), Polacca Wash near Second Mesa 09400568 (1994 to 2016), and Pasture Canyon Springs 09401265 (2004 to 2016). Median winter flows (November through February) of each water year were used as an index of the amount of groundwater discharge at the above-named sites. For the period of record, the median winter flows have generally remained constant at Dinnebito Wash and Polacca Wash, whereas a decreasing trend was indicated at Moenkopi Wash and Pasture Canyon Springs. In 2016, water samples collected from three wells and four springs in the Black Mesa area were analyzed for selected chemical constituents, and the results were compared with previous analyses from the same wells and springs. Concentrations of dissolved solids, chloride, and sulfate have varied at all three wells for the period of record, but neither increasing nor decreasing trends over time were found. Dissolved solids, chloride, and sulfate concentrations increased at Moenkopi School Spring during the more than 25 years of record at that site. Concentrations of dissolved solids, chloride, and sulfate at Pasture Canyon Spring have not varied significantly (p>0.05) since the early 1980s, and there is no increasing or decreasing trend in those data. Concentrations of dissolved solids, chloride, and sulfate at Burro Spring and Unnamed Spring near Dennehotso have varied for the period of record, but there is no statistical trend in the data.

Arizona↗
USGS1982

Ground-water levels and water quality in an area near Topaz Lake, Douglas County, Nevada

Intensive residential development of land along the northwest shore of Topaz Lake has raised concern regarding the adequacy of the water supply and possible effects of septic-tank effluents on the quality of local ground water and the lake. Existing data on water levels, well construction, and water quality were compiled, and a limited program of water-level measurement and water-quality sampling was conducted during 1976-77 to provide documentation of current hydrologic conditions against which effects of future development may be measured. Water-level measurements show the presence of small independent aquifers near the periphery of the alluvial fan covering the study area and a main alluvial aquifer in which water levels fluctuate in direct response to annual changes in lake stage. The sampled ground water can be grouped into four chemical types--three based on the relative proportions of sulfate and bicarbonate and one based on an increased proportion of chloride plus nitrate. Frequency distributions of the observed occurrences of nitrate (as NO3), phosphate (as PO4), and chloride in ground water indicate thresholds for background concentrations of these constituents at 0 to 3, 0 to 0.35, and 0 to 6 milligrams per liter, respectively. Above-background concentrations of nitrate and phosphate in ground water may be attributable, in part, to natural sources of these constituents; however, septic-tank effluents have increased the concentrations of nitrate, chloride, and perhaps phosphate in at least two areas of the current development. Sampling for dissolved organic carbon and coliform bacteria in ground water detected no contamination by these potential indicators of pollution.

Nevada↗
USGS1980

January 1980 water levels, and data related to water-level changes, western and south-central Kansas

This report contains hydrologic data on water-level measurements in observation wells in western and south-central Kansas. The measurements were made in mid-winter, mostly in January, when pumping was minimal and water levels had recovered from the effects of pumping during the previous irrigation season. This report also provides basic hydrologic data for relating water-level changes from a "base-reference year" (pre-development year), a year of abnormally high rainfall and minimum pumpage (1966), and the previous year (1979). The "base-reference year" i s designated as 1950 for the northwestern and west-central areas, 1940 for the southwestern area, and 1944 for the south-central area. Water-level data in the south-central area also are compared with data for 1974. "Base-reference-year" water levels are based on measurements made during that year and on interpretation of water-table-contour maps. Tables in the report show the depths to water level in 1940, 1944, or 1950 (pre-development years), 1966, 1974, 1979, and 1980; water-level changes from 1940-80,1944-80,1950-80,1966-80,1974-80, and 1979-80; and the average annual changes from 1940-80, 1944-80, 1950-80, 1966-80, and 1974-80. Also shown are saturated thicknesses of the deposits in 1940, 1944, or 1950, and in 1980, as well as the percentage change in saturated thickness from 1940-80, 1944-80, or 1950-80. Maps in the report, drawn by digital plotter, show the location of observation wells where water-level measurements are made. The water-level rise or decline, 1979-80, is given to the nearest 0.01 foot; two values at the same location indicate separate wells in the same 10-acre tract. The annual water-level measurements are made by personnel of the Division of Water Resources of the Kansas State Board of Agriculture and of the U.S. Geological Survey. State-agency support for this program is provided through the Kansas Geological Survey. Wells in this report are numbered according to the Bureau of Land Manage- ment's system of land subdivision. In this system, the first set of digits of a well number indicates the township; the second set, the range east or west of the sixth principal meridian; and the third set, the section in which the well is situated. The first letter denotes the 160-acre tract within the section; the second, the 40-acre tract, and the third, the 10-acre tract. The letters, A, B, C, or D, are designated in a counterclockwise direction beginning in the northeast quadrant. Because there may be more than one well in a 10-acre tract, consecutive numbers, beginning with "1", are added in the order in which the data from the wells are collect. Explanation of geologic units in tables 1 and 2 are: QA, Quaternary alluvium; QU, undifferentiated Quaternary deposits; TO, Ogallala Formation; KN, Niobrara Formation; KU, undifferentiated Lower Cretaceous rocks; KJ, undiffer-rentiated Lower Cretaceous and Upper Jurassic rocks.

Kansas↗
USGS1998

Ground-water hydrology and simulation of ground-water flow at Operable Unit 3 and surrounding region, U.S. Naval Air Station, Jacksonville, Florida

The Naval Air Station, Jacksonville (herein referred to as the Station), occupies 3,800 acres adjacent to the St. Johns River in Duval County, Florida. Operable Unit 3 (OU3) occupies 134 acres on the eastern side of the Station and has been used for industrial and commercial purposes since World War II. Ground water contaminated by chlorinated organic compounds has been detected in the surficial aquifer at OU3. The U.S. Navy and U.S. Geological Survey (USGS) conducted a cooperative hydrologic study to evaluate the potential for ground water discharge to the neighboring St. Johns River. A ground-water flow model, previously developed for the area, was recalibrated for use in this study. At the Station, the surficial aquifer is exposed at land surface and forms the uppermost permeable unit. The aquifer ranges in thickness from 30 to 100 feet and consists of unconsolidated silty sands interbedded with local beds of clay. The low-permeability clays of the Hawthorn Group form the base of the aquifer. The USGS previously conducted a ground-water investigation at the Station that included the development and calibration of a 1-layer regional ground-water flow model. For this investigation, the regional model was recalibrated using additional data collected after the original calibration. The recalibrated model was then used to establish the boundaries for a smaller subregional model roughly centered on OU3. Within the subregional model, the surficial aquifer is composed of distinct upper and intermediate layers. The upper layer extends from land surface to a depth of approximately 15 feet below sea level; the intermediate layer extends from the upper layer down to the top of the Hawthorn Group. In the northern and central parts of OU3, the upper and intermediate layers are separated by a low-permeability clay layer. Horizontal hydraulic conductivities in the upper layer, determined from aquifer tests, range from 0.19 to 3.8 feet per day. The horizontal hydraulic conductivity in the intermediate layer, determined from one aquifer test, is 20 feet per day. An extensive stormwater drainage system is present at OU3 and the surrounding area. Some of the stormwater drains have been documented to be draining ground water from the upper layer of the surficial aquifer, whereas other drains are only suspected to be draining ground water. The subregional model contained 78 rows and 148 columns of square model cells that were 100 feet on each side. Vertically, the surficial aquifer was divided into two layers; layer 1 represented the upper layer and layer 2 represented the intermediate layer. Steady-state ground-water flow conditions were assumed. The model was calibrated to head data collected on October 29 and 30, 1996. After calibration, the model matched all 67 measured heads to within the calibration criterion of 1 foot; and 48 of 67 simulated heads (72 percent) were within 0.5 foot. Model simulated recharge rates ranged from 0.4 inch per year in areas that were largely paved to 13.0 inches per year in irrigated areas. Simulated hydraulic conductivities in the upper layer at OU3 ranged from 0.5 foot per day in the north to 1.0 foot per day in the south. Simulated vertical leakance between the upper and intermediate layers ranged from 1.0x10-6 per day in an area with low-permeability clays to 4.3x10-2 per day in an area that had been dredged. Simulated transmissivities in the intermediate layer ranged from 25 feet squared per day in an area of low-permeability channel-fill deposits to a high of 1,200 feet squared per day in areas covering most of OU3. Simulated riverbed conductances ranged from 4 to 60 feet squared per day and simulated bottom conductances of leaking stormwater drains ranged from 5 to 20 feet squared per day. The direction and velocity of ground-water flow was determined using particle-tracking techniques. Ground-water flow in the upper layer was generally eastward toward the St. Johns River. However, leaking stormwater drains locally modified the flow system to create small areas with flow that was diverted to the drains. The flow velocities in the upper layer at OU3 were slow, averaging about 2 feet per year. The slow velocities were primarily the result of the low horizontal hydraulic conductivity and, secondarily, the result of the low recharge rate. The simulated rate at which ground water leaked into the stormwater drains was low, averaging about 0.0011 cubic feet per second per 100 feet of stormwater drainage conduit. Ground-water flow in the intermediate layer moved eastward toward and discharged into the St. Johns River. Flow velocities were significantly higher in this layer than in the upper layer. The velocity was about 35 and 12 feet per year in the northern and southern parts of OU3, respectively.

Florida↗
USGS2014

Simulated and measured water levels and estimated water-level changes in the Albuquerque area, central New Mexico, 1950-2012

The City of Albuquerque, the major population center in New Mexico, underwent a more than fivefold population increase between 1950 and 2010. Before 2009, groundwater was the primary source of the City of Albuquerque’s municipal water supply, but since that time, the city has diverted water through the San Juan-Chama Drinking Water Project to augment municipal water supplies. Consequently, there is interest in understanding how groundwater levels changed in response to groundwater pumping, surface-water diversions, and conservation measures. To give a more detailed history of water-level changes from 1950 through 2012, the U.S. Geological Survey, in cooperation with the Albuquerque Bernalillo County Water Utility Authority, created maps showing water-level contours and changes by contouring water-table elevations and production-zone hydraulic heads that were simulated with a recently updated regional-scale transient groundwater-flow model at 10-year intervals from 1950 to 2000 and again for 2008. Both the water-table elevations and production-zone hydraulic heads declined over time with the largest change occurring between 1970 and 1980, which was a period of rapid population growth and groundwater use. Declines in the water-table elevations and production-zone hydraulic heads are focused around major pumping centers and are largest in the production zone. Hydrographs from nine production-zone piezometers in the modeled area indicated varying responses to the increased use of surface-water diversions during 2009–12, with responses related to the locations of the wells within the study area and their proximity to pumping centers and the Rio Grande.

New Mexico↗
USGS2004

Simulation of ground-water flow, surface-water flow, and a deep sewer tunnel system in the Menomonee Valley, Milwaukee, Wisconsin

Numerical models were constructed for simulation of ground-water flow in the Menomonee Valley Brownfield, in Milwaukee, Wisconsin. An understanding of ground-water flow is necessary to develop an efficient program to sample ground water for contaminants. Models were constructed in a stepwise fashion, beginning with a regional, single-layer, analytic-element model (GFLOW code) that provided boundary conditions for a local, eight layer, finite-difference model (MODFLOW code) centered on the Menomonee Valley Brownfield. The primary source of ground water to the models is recharge over the model domains; primary sinks for ground water within the models are surface-water features and the Milwaukee Metropolitan Sewerage District Inline Storage System (ISS). Calibration targets were hydraulic heads, surface-water fluxes, vertical gradients, and ground-water infiltration to the ISS. Simulation of ground-water flow by use of the MODFLOW model indicates that about 73 percent of recharge within the MODFLOW domain circulates to the ISS and 27 percent discharges to gaining surface-water bodies. In addition, infiltration to the ISS comes from the following sources: 36 percent from recharge within the model domain, 45 percent from lateral flow into the domain, 15 percent from Lake Michigan, and 4 percent from other surface-water bodies. Particle tracking reveals that the median traveltime from the recharge point to surface-water features is 8 years; the median time to the ISS is 255 years. The traveltimes to the ISS are least over the northern part of the valley, where dolomite is near the land surface. The distribution of traveltimes in the MODFLOW simulation is greatly influenced by the effective porosity values assigned to the various lithologies.

Wisconsin↗
USGS2006

Effects of streambank fencing of pasture land on benthic macroinvertebrates and the quality of surface water and shallow ground water in the Big Spring Run basin of Mill Creek watershed, Lancaster County, Pennsylvania, 1993-2001

Streambank fencing along stream channels in pastured areas and the exclusion of pasture animals from the channel are best-management practices designed to reduce nutrient and suspended-sediment yields from drainage basins. Establishment of vegetation in the fenced area helps to stabilize streambanks and provides better habitat for wildlife in and near the stream. This study documented the effectiveness of a 5- to 12-foot-wide buffer strip on the quality of surface water and near-stream ground water in a 1.42-mi2 treatment basin in Lancaster County, Pa. Two miles of stream were fenced in the basin in 1997 following a 3- to 4-year pre-treatment period of monitoring surface- and ground-water variables in the treatment and control basins. Changes in surface- and ground-water quality were monitored for about 4 years after fence installation. To alleviate problems in result interpretation associated with climatic and hydrologic variation over the study period, a nested experimental design including paired-basin and upstream/downstream components was used to study the effects of fencing on surface-water quality and benthic-macroinvertebrate communities. Five surface-water sites, one at the outlet of a 1.77-mi2 control basin (C-1), two sites in the treatment basin (T-3 and T-4) that were above any fence installation, and two sites (one at an upstream tributary site (T-2) and one at the outlet (T-1)) that were treated, were sampled intensively. Low-flow samples were collected at each site (approximately 25-30 per year at each site), and stormflow was sampled with automatic samplers at all sites except T-3. For each site where stormflow was sampled, from 35 to 60 percent of the storm events were sampled over the entire study period. Surface-water sites were sampled for analyses of nutrients, suspended sediment, and fecal streptococcus (only low-flow samples), with field parameters (only low-flow samples) measured during sample collection. Benthic-macroinvertebrate samples were collected in May and September of each year; samples were collected at the outlet of the control and treatment basins and at three upstream sites, two in the treatment basin and one in the control basin. For each benthic-macroinvertebrate sample: Stream riffles and pools were sampled using the kick-net method; habitat was characterized using Rapid Bioassessment Protocols (RBP); water-quality samples were collected for nutrients and suspended sediment; stream field parameters were measured; and multiple biological metrics were calculated. The experimental design to study the effects of fencing on the quality of near-stream shallow ground water involved a nested well approach. Two well nests were in the treatment basin, one each at surface-water sites T-1 and T-2. Within each well nest, the data from one deep well and three shallow wells (no greater than 12 ft deep) were used for regional characterization of ground-water quality. At each site, two of the shallow wells were inside the eventual fence (treated wells); the other shallow well was outside the eventual fence (control well). The wells were sampled monthly, primarily during periods with little to no recharge, for laboratory analysis of nutrients and fecal streptococcus; field parameters of water quality also were measured.

Pennsylvania↗
USGS2007

Surface-water, ground-water, and sediment geochemistry of epizonal and shear-hosted mineral deposits in the Tintina Gold Province--Arsenic and antimony distribution and mobility

Epigenetic mineral deposits in the Tintina Gold Province are generally characterized by high concentrations of arsenic and antimony in their mineral assemblage. A total of 347 samples (ground water, surface water, and stream sediment) were collected to investigate the distribution and mobility of arsenic and antimony in the environment near known mineral deposits. Samples were collected from east to west at Keno Hill and Brewery Creek, Yukon, Canada; and Cleary Hill, True North, Scrafford Mine, Fairbanks, Ryan Lode, Stampede Creek, Slate Creek, and Donlin Creek, all in Alaska. Surface- and ground-water samples are all slightly acidic to near-neutral in pH (5-8), have a wide range in specific conductance (surface water 17-2,980 microsiemens per centimeter and ground water 170-2,940 microsiemens per centimeter), and show elevated dissolved arsenic and antimony concentrations (arsenic in surface water is less than 1 to 380 micrograms per liter and in ground water is less than 1 micrograms per liter to 1.5 milligrams per liter; antimony in surface water is less than 2 to 660 micrograms per liter and in ground water is less than 2 to 60 micrograms per liter). Stream sediments downstream from these deposits have high concentrations of arsenic and antimony (arsenic median is 1,670 parts per million, maximum is 10,000 parts per million; antimony median is 192 parts per million, maximum is 7,200 parts per million). The mobility of arsenic and antimony is controlled by the local redox environment, with arsenic being less mobile in oxidized surface waters relative to antimony, and arsenic more mobile in reduced ground water. These factors suggest that both antimony and arsenic may be useful pathfinder elements in water and sediment for targeting similar style deposits elsewhere in the Tintina Gold Province.

Alaska, Yukon↗
USGS2008

Spatial Distribution of Ground-Water Recharge Estimated with a Water-Budget Method for the Jordan Creek Watershed, Lehigh County, Pennsylvania

This report presents the results of a study by the U.S. Geological Survey, in cooperation with the Pennsylvania Geological Survey, to illustrate a water-budget method for mapping the spatial distribution of ground-water recharge for a 76-square-mile part of the Jordan Creek watershed, northwest of Allentown, in Lehigh County, Pennsylvania. Recharge was estimated by using the Hydrological Evaluation of Landfill Performance (HELP) water-budget model for 577 landscape units in Jordan Creek watershed, delineated on the basis of their soils, land use/land cover, and mean annual precipitation during 1951-2000. The water-budget model routes precipitation falling on each landscape unit to components of evapotranspiration, surface runoff, storage, and vertical percolation (recharge) for a five-layer soil column on a daily basis. The spatial distribution of mean annual recharge during 1951-2000 for each landscape unit was mapped by the use of a geographic information system. Recharge simulated by the water-budget model in Jordan Creek watershed during 1951-2000 averaged 12.3 inches per year and ranged by landscape unit from 0.11 to 17.05 inches per year. Mean annual recharge during 1951-2000 simulated by the water-budget model was most sensitive to changes to input values for precipitation and runoff-curve number. Mean annual recharge values for the crop, forest, pasture, and low-density urban land-use/land-cover classes were similar (11.2 to 12.2 inches per year) but were substantially less for high-density urban (6.8 inches per year), herbaceous wetlands (2.5 inches per year), and forested wetlands (1.3 inches per year). Recharge rates simulated for the crop, forest, pasture, and low-density urban land-cover classes were similar because those land-use/land-cover classes are represented in the model with parameter values that either did not significantly affect simulated recharge or tended to have offsetting effects on recharge. For example, for landscapes with forest land cover, values of runoff-curve number assigned to the model were smaller than for other land-use/land-cover classes (causing more recharge and less runoff), but the maximum depth of evapotranspiration was larger than for other land-use/ land-cover classes because of deeper root penetration in forests (causing more evapotranspiration and less recharge). The smaller simulated recharge for high-density urban and wetland land-use/land-cover classes was caused by the large values of runoff-curve number (greater than 90) assigned to those classes. The large runoff-curve number, however, certainly is not realistic for all wetlands; some wetlands act as areas of ground-water discharge and some as areas of recharge. Simulated mean annual recharge computed by the water-budget model for the 53-square-mile part of the watershed upstream from the streamflow-gaging station near Schnecksville was compared to estimates of recharge and base flow determined by analysis of streamflow records from 1967 to 2000. The mean annual recharge of 12.4 inches per year simulated by the water-budget method for 1967-2000 was less than estimates of mean annual recharge of 19.3 inches per year computed from the RORA computer program and base flow computed by the PART computer program (15.1 inches per year). In theory, the water-budget method provides a practical tool for estimating differences in recharge at local scales of interest, and the watershed- average recharge rate of 12.4 inches per year computed by the method is reasonable. However, the mean annual surface runoff of 4.5 inches per year simulated by the model is unrealistically small. The sum of surface runoff and recharge simulated by the water-budget model (16.9 inches per year) is 7 inches per year less than the streamflow measured at the gaging station near Schnecksville (23.9 inches per year) during 1967-2000, indicating that evapotranspiration is overestimated by the water-budget model by that amount. This discrepancy ca

Scientific Investigations Report↗