This report discusses the prevention of surface water pollution with hog wastes from point sources, and relates it to major structural characteristics of hog production. Nonpoint source pollution, arising from pasture systems and the application of hog wastes to farmland, is recognized but not evaluated. This analysis centers on the 15 major hog-producing States. In 1969, they accounted for 511,000 farms selling hogs, and for 89 percent of U.S. hog output. A third of total sales came from 368,000 farms selling fewer than 200 hogs each annually; 12 percent of sales were from farms selling 1,000 head or more. Open-lot systems of production accounted for 58 percent of all systems; pasture, 33 percent; and total confinement, 9 percent. Uncontrolled runoff is estimated to occur on 112,000 farms; 86,000 of them use open-lot systems. Effluent guidelines used in this report were assumed, since EPA guidelines had not been issued when this study was made. Under these assumptions, application of runoff control facilities to open-lot systems with problems would require investments in the 15 States of $254 to $290 million, and increased annual costs of $36 to $44, or $0.90 to $1.00 per 100 pounds of hogs produced. Unit investments and annual costs would be over 10 times as great for the smallest as for the largest enterprises. After control adjustments are complete, water should be free of hog wastes; pork should cost consumers little or no more as a result of the clean-up program. During the adjustment period some producers, agribusiness firms, and rural communities will suffer; pork supplies are likely to drop and prices to rise. Undesirable economic impacts can be minimized through proper application of regulations