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D.W. Anning

Publications and source records attributed to D.W. Anning.

6 recordsLinked to original sources

Modeled sources, transport, and accumulation of dissolved solids in water resources of the southwestern United States

Information on important source areas for dissolved solids in streams of the southwestern United States, the relative share of deliveries of dissolved solids to streams from natural and human sources, and the potential for salt accumulation in soil or groundwater was developed using a SPAtially Referenced Regressions On Watershed attributes model. Predicted area‐normalized reach‐catchment delivery rates of dissolved solids to streams ranged from <10 (kg/year)/km 2 for catchments with little or no natural or human‐related solute sources in them to 563,000 (kg/year)/km 2 for catchments that were almost entirely cultivated land. For the region as a whole, geologic units contributed 44% of the dissolved‐solids deliveries to streams and the remaining 56% of the deliveries came from the release of solutes through irrigation of cultivated and pasture lands, which comprise only 2.5% of the land area. Dissolved‐solids accumulation is manifested as precipitated salts in the soil or underlying sediments, and (or) dissolved salts in soil‐pore or sediment‐pore water, or groundwater, and therefore represents a potential for aquifer contamination. Accumulation rates were <10,000 (kg/year)/km 2 for many hydrologic accounting units (large river basins), but were more than 40,000 (kg/year)/km 2 for the Middle Gila, Lower Gila‐Agua Fria, Lower Gila, Lower Bear, Great Salt Lake accounting units, and 247,000 (kg/year)/km 2 for the Salton Sea accounting unit.

Arizona, California, Colorado, Nevada, Utah, New M↗

Southwest principal aquifers regional ground-water quality assessment

The National Water-Quality Assessment (NAWQA) Program of the U.S. Geological Survey is conducting a regional analysis of water quality in the principal aquifers in the southwestern United States. The Southwest Principal Aquifers (SWPA) study is building a better understanding of the susceptibility and vulnerability of basin-fill aquifers in the region to ground-water contamination by synthesizing the baseline knowledge of ground-water quality conditions in 15 basins previously studied by the NAWQA Program. The improved understanding of aquifer susceptibility and vulnerability to contamination is assisting in the development of tools that water managers can use to assess and protect the quality of ground-water resources. This fact sheet provides an overview of the basin-fill aquifers in the southwestern United States and description of the completed and planned regional analyses of ground-water quality being performed by the SWPA study.

Arizona, California, Colorado, Idaho, Nevada, New ↗

Uncertainty in low-flow data from three streamflow-gaging stations on the upper Verde River, Arizona

The evaluation of uncertainty in low-flow data collected from three streamflow-gaging stations on the upper Verde River, Arizona, was presented. In downstream order, the stations are Verde River near Paulden, Verde River near Clarkdale, and Verde River near Camp Verde. A monitoring objective of the evaluation was to characterize discharge of the lower flow regime through a variety of procedures such as frequency analysis and base-flow analysis. For Verde River near Paulden and near Camp Verde, the uncertainty of daily low flows can be reduced by decreasing the uncertainty of discharge-measurement frequency, or building an artificial control that would have a stable stage-discharge relation over time.

Conference Paper↗

Water resources data, Arizona water year 1994

The Water Resources Division of the U.S. Geological Survey, in cooperation with State agencies, obtains a large amount of data pertaining to the water resources of Arizona each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, the data are published annually in this report series entitled "Water Resources Data for Arizona."

Arizona↗

Summary of ground-water conditions in Arizona, 1987-90

Annual ground-water withdrawals in Arizona were 2.9, 3.3, 3.6, and 3.4 million acre-feet for calendar years 1987. 1988, 1989, and 1990. The average annual ground-water withdrawal for Arizona from 1980-89 was 3.7 million acre-feet, which was the lowest average annual withdrawal for any decade since the 1940' s. Since 1947, annual ground-water withdrawals in Arizona were at the lowest rate in 1983 and at the second lowest rate in 1987. For 1987-90, the distribution of ground-water use was 11.8 percent for municipal, 8.3 percent for industnal, 72.6 percent for agriculture, and 7.3 percent for draining irrigated lands. More than 94 percent of the ground-water withdrawals in Arizona occurred in the Basin and Range lowlands province during 1987-90. This province contains the two areas with the largest rates of ground-water withdrawal in Arizona--the Salt River Valley and the lower Santa Cruz basin. The average annual ground-water withdrawal for the Salt River Valley from 1980-89 is 1,013,000 acre-feet, which is the lowest average annual withdrawal for any decade since the 1930 's. Ground-water withdrawals in the lower Santa Cruz basin during 1990 were the lowest on record since 1940. In 1985, the Central Arizona Project began delivering Colorado River water to central Arizona to mitigate ground-water overdraft. The Harquahala basin began receiving water from the Central Arizona Project in 1985. From 1985 to 1990, ground-water withdrawals decreased from 59,000 acre-feet to 2,000 acre-feet, and water levels rose as much as 70 feet.

Arizona↗

Water resources data, Arizona water year 1993

The Water Resources Division of the U.S. Geological Survey, in cooperation with State agencies, obtains a large amount of data pertaining to the water resources of Arizona each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the State. To make these data readily available to interested parties outside the Geological Survey, the data are published annually in this report series entitled "Water Resources Data for Arizona."

Arizona↗