Runoff Coefficients of High-flow Events in Undisturbed New England Basins

The New England region in the Northeast U.S. receives high annual precipitation as rain and snow, which results in floods that endanger people and infrastructure. Owing to the complexity of hydrologic systems, increases in the frequency and intensity of large precipitation events do not always translate into increases in surface runoff measured as event flow at the basin outlet. However, recent studies have recognized positive trends in the frequency and magnitude of high-flow events in New England. For high-flow events of equal or greater than 2-year daily runoff, the runoff coefficients, or the fraction of precipitation converted into surface runoff during an event, were determined for 28 undisturbed New England basins with natural flow conditions. Results indicated that runoff coefficients increase in magnitude and variability with distance from the Atlantic coast toward the north and west. The average runoff coefficient of high-flow events across all basins is 0.90, while there exist many high-flow ev...