Convert Gallon (US) (gal (US)) to Acre-Foot (ac*ft) instantly.
About these units
Gallon (US) (gal (US))
The US gallon is defined as exactly 231 cubic inches, or 3.785411784 liters. It is widely used in American commerce for gasoline, milk, water, and other household liquids. Its historical roots lie in old English wine and ale gallons, whose varying definitions ultimately led to divergent US and UK systems. Today, the US gallon remains deeply embedded in American culture, especially in automotive contexts—fuel economy ratings such as "miles per gallon" (MPG) illustrate its everyday relevance. Despite the global shift toward metric volume units, the US gallon persists due to familiarity and regulatory inertia. It remains an iconic unit, symbolizing uniquely American measurement traditions.
Acre-Foot (ac*ft)
An acre-foot represents the volume of water needed to cover one acre of land to a depth of one foot—approximately 1,233.48 cubic meters or 325,851 gallons. This unit is foundational in water resource management throughout the western United States, where large-scale irrigation, reservoir planning, and drought analysis depend on acre-foot measurements. For example, major reservoirs like Lake Mead and Lake Powell hold billions of acre-feet. In agriculture, irrigation districts track water rights and allocations using acre-feet, making it a key component of water law. Its scale is ideal for representing the enormous water needs associated with farming, urban expansion, and environmental preservation.