Estimated average annual ground-water pumpage in the Portland Basin, Oregon and Washington 1987-88

Data for ground-water pumpage were collected during an inventory of wells in 1987-88 in the Portland Basin located in northwestern Oregon and southwestern Washington. Estimates of annual ground-water pumpage were made for the three major categories of use: public supply, industry, and irrigation. A large rapidly expanding metropolitan area is situated within the Portland Basin, along with several large industries that use significant quantities of ground water. The estimated total average annual ground-water pumpage for 1987 was about 127,800 acre-feet. Of this quantity, about 50 percent was pumped for industrial use, about 40 percent for public supply and about 10 percent for irrigation. Domestic use from individual wells is a small part of the total and is not included.