Estimated 2012 Groundwater Potentiometric Surface and Drawdown from Predevelopment, Santa Fe Group Aquifer System

Modifications in the demand for water and the source of the supply of water for the Albuquerque metropolitan area has resulted in a variable response in the potentiometric surface of the production zone of the Santa Fe Group aquifer (from about 300 to 1100 feet or more below land surface). Analysis of the magnitude and pattern of the response of the potentiometric surface can help improve understanding of how the groundwater system responds to withdrawals and variations in water supply management. The U.S. Geological Survey, in cooperation with the Albuquerque Bernalillo County Water Utility Authority, has mapped the estimated potentiometric surface for the winter season (December to March) of water year 2012 and the estimated drawdown between predevelopment and 2012 for the production zone in the Albuquerque and surrounding metropolitan areas. The 2012 potentiometric surface indicates that the general direction of groundwater flow is from the Rio Grande towards clusters of production wells in the north, east, and west. Drawdown is negligible in the southwest where groundwater withdrawals are minimal, and along the Rio Grande where recharge from the river is occurring. Drawdown is largest along the eastern margin (decline of more than 120 ft) and in the northwest (decline of more than 60 ft). Water-level measurements (representative of the potentiometric head in a well) from piezometers on the east side of the river generally indicate an increase in the annual highest water-level measurement from 2008-2012. Water-level measurements from piezometers in the northwest indicate either steady decline over the period of record or variable trends in which water levels increased for a number of years but declined beginning in 2012. Water-level measurements from a piezometer in the southwest indicate average increases of slightly more than 1 foot per year for the period of record.