Due to the occurrence high-intensity rainfall events more frequently than expected, the Michigan Department of Transportation has deemed it necessary to Update the regional rainfall intensity-duration-frequency (IDF) estimates for the State. Rainfall intensity estimates are to be determined for each of seven durations (1, 2, 3, 6, 12, 18 and 24 hours) and six frequencies (0.5, 0.2, O.1, 0.04, 0.02. and 0.01 per year). Traditionally, method of moments or maximum likelihood procedures have been used to fit a suitable probability distribution to annual maximum or partial duration series data for each gage, and isopluvial maps have been developed from these site-specific IDF estimates using interpolation procedures and judgment. This paper [...]
