The U.S. Geological Survey Has Found Ancient Groundwater Under Maryland
Some of the water under Maryland is older than a million years, the first such ancient groundwater found along the Atlantic Coast, the U.S. Geological Survey reports. There are relatively few aquifers in the world in which million-year-old groundwater has been documented These include the Nubian aquifer in the Sahara Desert, Canada’s Alberta Basin, and the Great Artesian Basin in Australia. The ancient water under Maryland resides in the Patapsco aquifer.
The Maryland aquifer provides freshwater for the region east of Washington and Baltimore. Modern-day pumping rates have lowered water pressures and changed water chemistry, affecting the aquifer’s ability to provide freshwater for drinking and other uses. Concerns over saltwater intrusion in some areas have led water managers to increasingly move groundwater production from shallower aquifers to the deeper upper Patapsco aquifer, which has caused groundwater levels to decline.
The USGS has a “groundwater watch” database containing records from about 850,000 U.S. wells over the past 100 years.