Equations for estimating flood magnitudes at selected recurrence intervals from 2 to 500 years were developed using multiple-regression analyses. These equations relate flood magnitudes to basin characteristics, contributing drainage area and site altitude, and only are applicable to unregulated streams in New Mexico that are relatively unaffected by urban runoff. Estimates of floods at or near gaged sites may be computed with an equation that adjusts discharges developed with the regression equations using station-specific discharges. (USGS)