Pumpage of ground water and changes in water levels in Galveston County, Texas, 1958-62.

The quantity of water used in Galveston County during the period 1958- 62 was nearly constant, ranging from 86 mgd (million gallons per day) in 1960 to 88 mgd in 1961. Of the 1961 total, 21 mgd was ground water and 67 mgd was water from the Brazos River. Ground-water withdrawals in Galveston County has declined slightly since 1957, ranging from 27.8 mgd in 1959 to 21.5 mgd in 1961. In 1961, 15.7 mgd was used for public supply, 5.3 for industry, and 0.5 for irrigation. Between 1958 and 1962, industrial pumpage ranged from 6.3 mgd in 1959 to 5.3 mgd in 1961; withdrawal for public supply ranged from 15.6 mgd in 1958 to 16.7 mgd in 1960. Pumpage for irrigation in Galveston County ranged from 0.5 mgd in 1960-61 to 1.5 mgd in 1958. Water levels in wells in Galveston County changed very little in some areas and declined slowly in others during the period 1958-62. In the city of Galveston's well fields near Alta Loma, near the center of pumping, they have remained about the same, but in outlying areas they have declined somewhat, especially near the Harris County line, where the maximum decline was 25 feet between 1957 and 1962. Levels in Texas City and vicinity have remained nearly stable. Land-surface subsidence continued during the period, ranging from 0.1 to 0.5 foot. The greatest subsidence was 0.5 foot at League City. No major changes were noted in the chemical quality of water from wells. The average quality of water from the city of Galveston's old well field has improved slightly. The chloride content of water from one well in the new well field continued to increase slowly.