Convert Barrel (Oil) (bbl (oil)) to Acre-Foot (US Survey) (ac*ft (US)) instantly.
About these units
Barrel (Oil) (bbl (oil))
An oil barrel is defined as 42 US gallons, or 158.987 liters, and is a fundamental unit in the petroleum industry. This peculiar size traces back to the early Pennsylvania oil fields, where producers standardized whiskey barrels and modified wooden casks for oil transport. The need for consistent trade volumes cemented the 42-gallon barrel as the industry norm. Today, global oil production, pricing, and consumption are expressed in barrels—from daily OPEC reports to energy market forecasts. Even though oil is no longer physically shipped in barrels, the unit remains deeply embedded in international energy economics.
Acre-Foot (US Survey) (ac*ft (US))
The US survey acre-foot differs extremely slightly from the international acre-foot due to the slight difference between the survey foot and the international foot. While the distinction is negligible in most contexts, it is important in surveying, legal water rights, and long-term hydrological accounting, especially in regions where large historical datasets were recorded using US survey measures. This variant highlights how even subtle unit differences can have major implications when dealing with huge volumes over long timescales, such as state water budgets and inter-state compacts.