Publications

National Water Summary 1990-91 Hydrologic Events and Stream Water Quality was planned to complement existing Federal-State water-quality reporting to the U.S. Congress that is required by the Clean Water Act of 1972. This act, formally known as the Federal Water Pollution Control Act Amendments of 1972 (Public Law 92-500), and its amendments in 1977,1979,1980,1981,1983, and 1987, is the...

This report is one in a series of reports that annually depict altitudes of water levels since 1977, the most recent of which (Barbie and others, 1991) presented maps of the altitudes of water levels for 1990. This report was prepared in cooperation with the City of Houston and the Harris-Galveston Coastal Subsidence District, and preents approximate altitudes of water levels in wells in...

This report is one in a series of reports that depict water-level changes since 1977 and compaction of subsurface material since 1973. The report was prepared in cooperation with the Harris-Galveston Coastal Subsidence District and the City of Houston, and presents maps showing the approximate changes in water levels in wells completed in the Chicot and Evangeline aquifers, 1977-93 and...

No abstract available.

The Edwards aquifer is the principal source of freshwater for municipal, domestic, and industrial users in the Georgetown area. Other sources of freshwater are Lake Georgetown and the streams draining the San Gabriel River basin. Lake Georgetown, located on the North Fork San Gabriel River west of Georgetown, is a freshwater supply for some municipalities in the area. Water in the San...

Remote-sensing data were used to estimate that 190,000 acre-feet of water was pumped from the Edwards aquifer in 1989 to irrigate crops in Uvalde and Medina Counties. Landsat digital satellite images for March and July 1989 were combined and classified to identify the areas of crops irrigated with water from the Edwards aquifer in the two counties. Normalized difference, the difference...

This report was prepared in cooperation with the Fort Bend Subsidence District, and presents data on water-level changes during 1991-92 in the Chicot and Evangeline aquifer (fig. 1-2) in Fort Bend County. Water-level change maps were prepared previously by Locke (1990),and Locke and Barbie (1991), for both aquifers, and by Wesselman (1972) for the Chicot aquifer.

No abstract available.

This report presents hydrogeologic maps of the Central Oklahoma aquifer. The maps were prepared by measuring water levels in wells during the winder of 1986 and 1987; examination of geophysical logs to determine the altitudes of the top of selected geologic units and the base of fresh ground water; and compilation of existing information on the stratigraphy of selected geologic units and...

No abstract available.

The Edwards-Trinity aquifer system is underlain by an extensive complex of rocks, ranging from Late Cambrian through Late Triassic in age, that are typically about 10 to perhaps 1,000 times less permeable than those composing the aquifer system. The Cretaceous rocks of the aquifer system are separated from the pre-Cretaceous rocks by an unconformity that spans about 60 million years of...

This report is one in a series of reports that depict water-level changes since 1977 and compaction of subsurface material since 1973. The report was prepared in cooperation with the Harris-Galveston Coastal Subsidence District and the City of Houston, and presents maps showing the approximate changes in water-levels in wells completed in the Chicot and Evangeline aquifers, 1977-92 and...