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Stanley Baldys

Publications and source records attributed to Stanley Baldys.

23 records · Page 2Linked to original sources
USGS1995

Summary statistics and trend analysis of water-quality data at sites in the Gila River basin, New Mexico and Arizona

Summary statistics and temporal trends for 19 water-chemistry constituents and for turbidity were computed for 13 study sites in the Gila River basin, Arizona and New Mexico. A nonparametric technique, the seasonal Kendall tau test for flow-adjusted data, was used to analyze temporal changes in water-chemistry data. For the 19 selected constituents and turbidity, decreasing trends in concentrations outnumbered increasing trends by more than two to one. Decreasing trends in concentrations of constituents were found for 49 data sets at the 13 study sites. Gila River at Calva and Gila River above diversions, at Gillespie Dam (eight each) had the most decreasing trends for individual sites. The largest number of decreasing trends measured for a constituent was six for dissolved lead. The next largest number of decreasing trends for a constituent was for dissolved solids and total manganese (five each). Hardness, dissolved sodium, and dissolved chloride had decreasing trends at four of the study sites. Increasing trends in concen- trations of constituents were found for 24 data sets at the 13 study sites. The largest number of increasing trends measured for a single constituent was for pH (four), dissolved sulfate (three), dissolved chromium (three) and total manganese (three). Increased concentrations of constituents generally were found in three areas in the basin-at Pinal Creek above Inspiration Dam, at sites above reservoirs, and at sites on the main stem of the Gila River from Gillespie Dam to the mouth.

Water-Resources Investigations Report↗
USGS1994

Effects of controlled burning of chaparral on streamflow and sediment characteristics, East Fork Sycamore Creek, central Arizona

The effects of controlled burning of part of a chaparral-covered drainage basin on streamflow and sediment characteristics were studied in the upper reaches of the Sycamore Creek basin in central Arizona. A paired-watershed method was used to analyze data collected in two phases separated by the controlled burning of 45 percent of the East Fork Sycamore Creek drainage basin by the U.S. Forest Service on October 31, 1981. Statistically significant increases in streamflow in East Fork occurred from October 26, 1982, through August 25, 1984. Streamflow for August 26, 1984, through the end of data collection for the study on May 31, 1986, was generally at or less than preburn levels. An increase in the percentage of time that flow occurred in East Fork was noted for water years 1983 and 1984. No increase in the magnitude of instantaneous peak flows as a result of the burn was discernable at statistically significant levels. Suspended-sediment yields computed for data collected during water year 1983 were significantly greater in the East Fork drainage basin, 546 tons per square mile, than in the West Fork drainage basin, 22.6 tons per square mile. Suspended-sediment yields computed for East Fork and West Fork for water year 1985, 38.3 and 13.3 tons per square mile, respectively, were much closer in yield. These more uniform yields indicate a possible return to preburn conditions. Data collection did not begin until 11 months after the burn; therefore, the largest increases in streamflow and sediment yields, which commonly occur during the year after a burn, may not have been measured. During the second through fourth years after the burn, smaller increases in stream- flow and sediment yields were found in this study than were found in similar studies in this region.

Water-Resources Investigations Report↗
USGS1990

Flow characteristics of streams that drain the Fort Apache and San Carlos Indian reservations, east-central Arizona, 1930-86

Streamflow characteristics of the Salt River and Gila River basins in the Fort Apache and San Carlos Indian Reservations, were studied in response to pending adjudication of water resources in those basins. Statistical summaries were compiled for 28 streamflow-gaging stations in and near the reservation. Mean annual streamflow for 1930-86 was computed for stations with complete records for the period; for those stations with records that did not completely cover the 1930-86 period, record extension techniques were used. Mean annual streamflow for ungaged sites on streams with gaging stations was estimated by interpolation between data points using drainage-area ratios. Two regional-regression equations were derived to estimate mean annual streamflow at sites on ungaged natural streams. The standard error of the regression for estimation of mean annual flow for sites in the Salt River basin is -37 to +59%. The standard error of the regression for estimation of mean annual flow for sites in the Gila River basins is -18 to +21%. (USGS)

Water-Resources Investigations Report↗
USGS1985

Ground-water conditions in and near the Gila River Indian Reservation, south-central Arizona

In the early 1900 's when ground-water pumping began in the vicinity of the Gila River Indian Reservation, depths to water below the land surface ranged from less than 10 feet to about 130 feet and the general direction of ground-water flow was toward the northwest. In 1983, depths to water ranged from less than 50 feet to more than 700 feet. Water level decline since 1900 was more than 550 feet near Stanfield, 500 feet near Chandler Heights, and 350 feet east of Mesa and southeast of Eloy; about 100 feet near Sacaton; and less than 50 feet near Gila Crossing. In 1983, the ground water flowed westward toward the center of cones of depression east of Mesa; near Chandler Heights, Eloy, and Arizona City; and in the Maricopa-Stanfield area. An increase in the specific conductance of ground water has accompanied the lowering of water levels in many areas.

Water-Resources Investigations Report↗