Last week when Brad White of DEQ gave a talk at the Prince William Conservation Alliance, one of his slides struck a memory of a previous conversation I had with DEQ. Before the Covid pandemic shut down Virginia I had a conversation with DEQ about groundwater use in Fauquier and Prince William. I said, that these days after the abandonment of the groundwater supply wells in Manassas groundwater in that area wasn’t really used. I was corrected and told, no, Amazon has a reporting well in Manassas and IBM is leasing the PWSA well for a pump and treat for the groundwater contamination.
DEQ knew this because the Virginia Water Withdrawal Reporting Regulation requires the registration and annual reporting of surface water and groundwater withdrawals by January 31 of each year of any entity withdrawing more than 300,000 gallons per month (that is equivalent to the combined daily use of about 140 people). Though there is no control or management of the water withdrawals except in the Groundwater Management areas of Virginia, the information is collected, summarized and included in the Annual Water Resources Report and in the Virginia State Water Resources Plan. Of course, the way around the reporting requirements is to have several wells, none of which exceed the limit. It works the same way as multiple back up generators whose combined power equals a rather large on demand power plant that would never be allowed to operate on diesel as a combined entity is just fine as dozens upon of dozens of back up generators at the ever expanding fleet of data centers.So, that when Mr. White showed the slide below, he commented
that 40,000,000-70,000,000 gallons of groundwater a year was being used for a
pump and treatment system (the old IBM site) and 30,000,000-35,000,000 gallons
of groundwater a year was being used by an industrial user (who I believe to be
that Amazon data center previously mentioned by DEQ) . Should Virginia be
managing the amount of groundwater that is used and will be used in the future
for datacenters?
from DEQ |
The USGS recently published The Soil-Water-Balance Model to Estimate Recharge to Blue Ridge, Piedmont, and Mesozoic Basin Fractured-Rock Aquifers, Fauquier County, Virginia, 1996 through 2015 by By Kurt J. McCoy and David E. Ladd. That study found that the 20-year average recharge in Fauquier County from the SWB model ranged from 8.1 inches per year (in/yr) in Blue Ridge aquifers to 5.3 in/yr in Mesozoic basin aquifers. The authors noted that “although mean annual precipitation volumes vary slightly across the County, the contrast in recharge among the Blue Ridge and western Piedmont aquifers with that of the Mesozoic basin aquifers is largely a result of differences in soil infiltration capacity. Precipitation totals 20 percent below mean annual precipitation from 1996–2015 produced drought recharge rates that were less than 50 percent of mean annual recharge.”
the recharge in 2001 was less than 50% of the 20 year average |
Also noted is that “recharge is highest and most variable in deciduous forest areas overlying crystalline rock aquifers in the Blue Ridge geologic province. Annual recharge to aquifers in the Blue Ridge geologic province was strongly influenced by annual differences in precipitation. The lowest and least variable rates of recharge for the period of simulation were computed for pasture/hay or developed areas overlying sedimentary rock aquifers in the Mesozoic basin.” In Fauquier County if proliferation of data centers were to reduce areas of recharge where forests and pastures were removed and paved over with roadways, parking lots, data centers and substations and water use increased for cooling and other uses, they could overtax the groundwater aquifers that are the primary source of water supply for the county in a dry year and possibly not meet demand during an extended drought.
This is what happened in the Tidewater that is entirely
dependent on the Potomac groundwater aquifer. At one time the water resources
seemed unlimited, but they were not and resulted in the Groundwater Management
Act. Under the Ground Water Management Act of 1992 and the Groundwater Withdrawal Regulations, Virginia manages
groundwater in the two Groundwater Management Areas in the state. The Eastern
Virginia Groundwater Management Area and the Eastern Shore Groundwater
Management Area. The Eastern Virginia
Groundwater Management Area encompasses the counties of Charles City, Essex,
Gloucester, Isle of Wight, James City, King George, King and Queen, King
William, Lancaster, Mathews, Middlesex, New Kent, Northumberland, Prince
George, Richmond, Southampton, Surry, Sussex, Westmoreland, and York; and areas of Caroline, Chesterfield, Fairfax,
Hanover, Henrico, Prince William, Spotsylvania, and Stafford counties east of
Interstate 95; and the cities of Chesapeake, Franklin, Hampton, Hopewell,
Newport News, Norfolk, Poquoson, Portsmouth, Suffolk, Virginia Beach, and
Williamsburg. The Eastern Shore Groundwater Management Area encompasses the
counties of Accomack and Northampton. Any person or entity located within a declared
GWMA must obtain a permit to withdraw 300,000 gallons or more of groundwater in
any one month.
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