User's guide to SAC, a computer program for computing discharge by slope-area method

This user’s guide contains information on applying the slope-area computation program, SAC. SAC can be used to compute peak flood discharges from measurements of high-water marks along a stream reach. The slope-area method used by the program is based on the U.S. Geological Survey (USGS) procedure presented in Techniques of Water Resources Investigations of the U.S. Geological Survey, book 3, chapter A2, "Measurement of Peak Discharge by the Slope-Area Method". The program uses input files that have formats compatible with those used by the Water-Surface Profile (WSPRO) computer program. The guide briefly describes the slope-area method, documents the input requirements and the output produced, and demonstrates use of SAC.