Arizona's Basin and Range province is a awash with stored water. Over the past 25 million years, as normal faults lifted mountain blocks out of the subsurface, weathering and erosion have delivered sediments to nearby basins. Some basins contain more then 12,000 feet of unconsolidated sediment. Water streaming off nearby mountain ranges infiltrates those sediments building voluminous groundwater aquifers. Farmers tap groundwater to grow their crops.But the groundwater aquifer supply is not infinite, and at the rate we use it, it is a non-renewable resource.