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J.H. Eychaner

Publications and source records attributed to J.H. Eychaner.

6 recordsLinked to original sources
USGS2005

Measurements of aquifer-storage change and specific yield using gravity surveys

Pinal Creek is an intermittent stream that drains a 200-square-mile alluvial basin in central Arizona. Large changes in water levels and aquifer storage occur in an alluvial aquifer near the stream in response to periodic recharge and ground-water withdrawals. Outflow components of the ground-water budget and hydraulic properties of the alluvium are well-defined by field measurements; however, data are insufficient to adequately describe recharge, aquifer-storage change, and specific-yield values. An investigation was begun to assess the utility of temporal-gravity surveys to directly measure aquifer-storage change and estimate values of specific yield. The temporal-gravity surveys measured changes in the differences in gravity between two reference stations on bedrock and six stations at wells; changes are caused by variations in aquifer storage. Specific yield was estimated by dividing storage change by water-level change. Four surveys were done between February 21, 1991, and March 31, 1993. Gravity increased as much as 158 microGal ± 1 to 6 microGal, and water levels rose as much as 58 feet. Average specific yield at wells ranged from 0.16 to 0.21, and variations in specific yield with depth correlate with lithologic variations. Results indicate that temporal-gravity surveys can be used to estimate aquifer-storage change and specific yield of water-table aquifers where significant variations in water levels occur. Direct measurement of aquifer-storage change can eliminate a major unknown from the ground-water budget of arid basins and improve residual estimates of recharge.

Groundwater↗
USGS1989

Chemical, geologic, and hydrologic data from the study of acidic contamination in the Miami Wash-Pinal Creek area, Arizona, water years 1984-87

Occurrence and movement of acidic contamination in the aquifer and streams of the Pinal Creek basin near Globe, Arizona, is the focus of an ongoing study by the U.S. Geological Survey. Groundwater data from that study for water years 1984 to 1987 include location, construction information, and site plans for six groups of monitoring wells, mineralogic and particle-size analyses of drill cuttings, water level measurements, and chemical analyses of water samples from 39 wells. Surface water data for 13 sites in this study include discharge measurements and chemical analysis of water and streambed sediment samples. Monthly discharge data are presented for one site. Monthly precipitation amounts and statistics of long-term precipitation are presented for two sites. (USGS)

Open-File Report↗
USGS1988

Simulation of five ground-water withdrawal projections for the Black Mesa area, Navajo and Hopi Indian Reservations, Arizona

The N Aquifer is the main source of water in the 5,400 sq mi Black Mesa area in the Navajo and Hopi Indian Reservations in northeastern Arizona. Water in the aquifer is under confined conditions in the central 3,300 sq mi of the area. Maximum saturated thickness is about 1,050 ft. Annual groundwater withdrawals from 1972 through 1986 averaged 5,480 acre-ft and included 3,820 acre-ft used to operate a coal mine on Black Mesa. As a result, water levels have declined in a large part of the aquifer. The coal company has applied for a permanent permit under the Surface Mining Control and Reclamation Act of 1977. An existing mathematical model of the aquifer in the Black Mesa area was converted to a newer model program and recalibrated by using revised estimates of selected aquifer parameters and a finer spatial grid. The model was used to simulate four groundwater withdrawal alternatives that combined the existing and proposed mining plans with projected constant or increasing pumpage for nearby communities. A fifth alternative combined increasing community pumpage with no mine withdrawals and was used as a basis for comparison. Simulated water levels for the year 2031 in the coal-lease area are projected to be 60 ft lower than in 1985 for the proposed mining plan combined with growing community pumpage and > 100 ft lower than predevelopment water levels over an area of 1,660 sq mi. Groundwater would rise to within 100 ft of predevelopment levels < 10 yr after mine withdrawals cease. Withdrawals at the mine were a minor factor in determining simulated water levels at most communities in the study area. Water levels at Tuba City were not affected by mine pumpage in any projection. (Author 's abstract)

Water-Resources Investigations Report↗
USGS1982

Floods of October 1977 in southern Arizona and March 1978 in central Arizona

Major floods occurred in October 1977 and March 1978 in Arizona. As much as 14 inches of rain fell during October 6-9, 1977, over the mountains of southern Arizona and northern Mexico and caused the highest discharge since at least 1892 on the Santa Cruz River upstream from Tucson. The flood inundated areas as much as 4 miles wide, covered at least 16,000 acres of farmland, and caused $15.2 million in damage. Residential losses occurred at Nogales, Amado, Green Valley, and Sahuarita. Severe erosional damage occurred along the Santa Cruz River, Agua Fria Canyon, Potrero Creek, and many small drainages in the Sonoita Creek basin. The peak discharge in Agua Fria Canyon was the highest since before 1900. Less severe flooding occurred along the San Pedro River and the Gila River downstream from the San Pedro. Widespread rainfall of 3 to 6 inches and 9 to 14 inches in some areas in the central mountains during February 28 to March 3, 1978, caused the highest discharge since 1920 on the Salt River in Phoenix and resulted in three deaths. Flooding along the Salt and Gila Rivers and several lesser streams caused statewide damage totaling $65.9 million, of which about $37 million occurred in Maricopa County. Nine counties were declared disaster areas. During the flood of March 1978, moderate peak discharges and unusually high volumes of runoff occurred on tributaries to the Salt and Verde Rivers upstream from a system of reservoirs. Flood magnitudes were greater at the main-stem gaging stations than on the tributaries. The peak discharge into Theodore Roosevelt Lake, which was 21 percent full at the start of the flood, was about 155,000 cubic feet per second and is the largest known from 1890 to 1978. The reservoirs stored large quantities of water and greatly reduced the magnitude of the flood. The peak discharge of the Salt River was 125,000 cubic feet per second below Granite Reef Dam and 122,000 cubic feet per second at Phoenix. Discharges in excess of 100,000 cubic feet per second occurred for 8 hours. Without the storage provided by the reservoirs, the peak discharge would have been 260,000 cubic feet per second and the discharge would have exceeded 100,000 cubic feet per second for 66 hours. The Verde River was the principal flood source, but flows at the upstream gaging stations did not indicate the magnitude of the impending flood at Horseshoe Reservoir because large inflow from tributaries immediately upstream from the reservoir caused the river to rise at downstream stations before it rose at upstream stations. About 17 percent of the water entering the reach from Granite Reef Dam to Gillespie Dam went to recharge, temporary ground-water storage, or evapotranspiration losses. All water was stored at Painted Rock Reservoir and released at a low rate that prevented water from reaching the Gila River near Mohawk gaging station.

Arizona↗