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B. W. Thomsen

Publications and source records attributed to B. W. Thomsen.

9 recordsLinked to original sources
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↗
USGS1980

Flood of February 1980 along the Agua Fria River, Maricopa County, Arizona

The flood of February 20, 1980, along the Agua Fria River below Waddell Dam, Maricopa County, Ariz., was caused by heavy rains during February 13-20. The runoff filled Lake Pleasant and resulted in the largest release--66,600 cubic feet per second--from the reservoir since it was built in 1927; the maximum inflow to the reservoir was about 73,300 cubic feet per second. The area inundated by the releases includes about 28 miles along the channel from the mouth of the Agua Fria River to the Beardsley Canal flume crossing 5 miles downstream from Waddell Dam. The flood of 1980 into Lake Pleasant has a recurrence interval of about 47 years, whereas the flood of record (1919) has a recurrence interval of about 100 years. (USGS)

Open-File Report↗
USGS1978

Hydrologic data for the Copper Basin area, a potential mining area in Yavapai County, Arizona

Large low-grade ore bodies have been discovered in Copper Basin, and a large copper-mining operation is anticipated in the near future. Hydrologic data are being collected to provide the data base necessary to determine the effects of a potential mining operation on the water resources of the area. The area of potential depletion or contamination of water supplies is the 50-square-mile alluvial slope downgradient from Copper Basin. In the Copper Basin area the streams generally are dry, except for the perennial flow in a 3-mile-long reach of Kirkland Creek, where the base flow ranges from about 1 to 3 cubic feet per second. The water in the alluvium, which is more than 1,000 feet thick in places, generally is under unconfined conditions. The direction of ground-water movement is generally southwesterly toward Skull Valley Wash and Kirkland Creek. The depth to water in wells ranges from less than 10 to 675 feet below the land surface. Near the center of the area, test wells penetrate a clay confining bed at the base of the alluvium and an underlying sequence of volcanic rocks, which is more than 1,000 feet thick and contains water under confined conditions. Pump tests indicate that the confining bed forms a barrier between the water in the alluvium and the water in the volcanic rocks and that, initially, pumping from the volcanic rocks would not affect the water level in the alluvium. The areal extent of the volcanic sequence is not known.

Arizona↗
USGS1969

Water resources of the Sycamore Creek watershed, Maricopa County, Arizona

The Sycamore Creek watershed is representative of many small watersheds in the Southwest where much of the streamflow originates in the mountainous areas and disappears rather quickly into the alluvial deposits adjacent to the mountains. Five years of .streamflow records from the Sycamore Creek watershed show that an average annual water yield of 6,110 acre-feet was obtained from the 165 square miles (105,000 acres) of the upper hard-rock mountain area, which receives an average annual precipitation of about 20 inches. Only a small percentage of the ,annual water yield, however, reaches the Verde River as surface flow over the 9-mile reach of the alluvial channel below the mountain front. Flows must be more ,than 200 cubic feet per second to reach the river; flows less than this rate disappear into the 1,ower alluvial area and are stored temporarily in the ground-Water reservoir : most of this water is released as ground-water discharge to the Verde River at a relatively constant rate of about 4,000 acre-feet per year. Evapotranspiration losses in the lower alluvial area are controlled by the depth of the water table and averaged about 1,500 acre-feet per year.

Water Supply Paper↗
USGS1966

Water resources of Fort Huachuca Military Reservation, southeastern Arizona

The Fort Huachuca Military Reservation, on the northeast flank of the Huachuca Mountains, is in the southern part of the San Pedro River drainage in the Basin and Range physiographic province in Arizona. The main sources of water available in the reservation area are ground water stored in two unconsolidated sedimentary deposits filling the San Pedro basin, and spring flow in Garden ·and Huachuca Canyons in the Huachuca Mountains. The unconsolidated deposits are divided into the upper and lower units of basin flu. These units yield the major part of the fort's water supply, and pumping from them has caused the water level in the Fort Huachuca well field to decline 3 feet per year. All the upper unit and 40 feet of the 220-foot-thick lower unit have seen dewatered in post wells 1 and 2. In Garden Canyon, spring flow is derived from solution channels and fractures in carbonate rocks; and in Huachuca Canyon, from fractures in mudstone, sandstone, carbonate rocks, ·and granite. The flow from springs generally is not used by the fort, but it is sufficient to supply the entire water demand during some periods. Spring flow, if used to supplement the ground-water supply, will decrease the draft on the ground-water reservoir in the two basin-fill units; or it could be used for artificial recharge to these aquifers. A second well field, if developed in the North Gate-Libby Field area, would partly accomplish the same result by decreasing the heavily concentrated draft on the ground-water reservoir of the Fort Huachuca well field, and by utilizing ground water that now moves unused northeastward to the San Pedro River.

Arizona↗