Robert E. Horton was a prominent hydrologist and civil engineer in America and was known as the pioneer of modern American hydrology. His contribution to the field of hydrology was path-breaking, and some of the concepts he developed are still in use, such as his work on surface runoff, infiltration, drainage basins, etc. Horton is most famous for his laws of drainage networks and the idea of infiltration capacity, which is the rate at which soil takes water during rainfall. His works contributed to the modern ideas of flood forecasting, soil protection measures, and erosion prevention methods.

Horton was born in Parma, Michigan in 1875, received an engineering degree from Albion College, and became a hydrologist in the U.S. Geological Survey (USGS). In his early years of work, he conducted the experimental investigation of New York streams, where he formed the idea that the potential of rainfall to recharge the groundwater was directly proportional to the soil infiltration capacity. Horton's work divided the water cycle into such factors as infiltration, evaporation, and runoff, which provided the basis for quantitative hydrology. His later work in private consulting enabled him to continue his research with a specific emphasis on flood generation, soil erosion, and terrain runoff patterns while operating his Horton Hydrological Laboratory.

In 1933, Horton published The Role of Infiltration in the Hydrologic Cycle. He first proposed the idea of infiltration-excess overland flow, now termed Horton overland flow. This model changed how hydrologists and engineers think about it, especially in urban development and agriculture. Horton remained active in hydrology and produced more than a hundred scientific papers. He died in 1945, but his work is still significant in hydrology, as demonstrated by the many awards christened after him, such as the Robert E. Horton Medal awarded by the American Geophysical Union.