Every year, nearly 40% of California’s water used for drinking, agriculture, and irrigation comes from groundwater sources located in Northern California. During droughts, as much as 60% of water in California is sourced from groundwater. In addition, large quantities of California’s surface water (water found in lakes, rivers, stream, and reservoirs) provides a resource to citizens and farms in the state. However, since the 1922 Colorado River Compact, California is also able to draw up to 4.4 million acre feet per year from the Colorado River.