The rainfall intensity–duration–frequency (IDF) curves play a significant role in water resources engineering and management. An accurate rainfall estimate is the first step in any hydrologic analysis. The rainfall IDF relationship is one of the most widely used and most important hydrologic tools utilized by engineers in water resources engineering field, either in planning, designing and operating water resources, or flood control projects. The IDF curves are commonly used to assess rainfall events, to derive design storms and assist in designing drainage structures, storm sewers, culverts and other hydraulic structures in urban areas. The purpose of this research is to derive rainfall IDF curves of Hall County, Georgia. Gumbel and the Log Pearson Type III distribution frequency analysis techniques will be used to develop the IDF curves from rainfall data of the region. The goodness-of-fit test will be performed to determine the best fit probability distribution. Georgia Automated Environmental Monitoring Network (http://www.georgiaweather.net/) weather stations of Hall and surrounding Counties along with NOAA National Weather Service weather stations will be utilized in this study. The frequency analysis of available rainfall data and the parameters of the IDF equations and coefficient of correlation will be calculated by statistical methods to attain rainfall intensities for various short durations and return periods. The derived IDF curve for the study area will be compared with the Partial Duration Series Precipitation-Intensity-Duration-Frequency (PIDF) raster data created by NOAA (https://hdsc.nws.noaa.gov/hdsc/pfds/pfds_gis.html).
