Fauquier County depends almost entirely on groundwater drawn from fractured bedrock aquifers for drinking and irrigation water. Currently, the county uses 3.9 million gallons of water a day for public supply and domestic use. The availability of groundwater is dependent upon subsurface geologic conditions which are not uniform throughout the County. Fauquier County includes parts of the Blue Ridge, the Culpeper Basin, and the Piedmont geological province. A key factor isn’t just how much water you’re pumping out of the ground, but rather where in the watershed and in what geologic province you are pumping. Different locations within the county have different water availability. The County can’t change the underlying geology or control the rate or pattern of groundwater recharge. Instead Fauquier must yield to nature.
Sustainability and availability of groundwater resources in Fauquier County is a concern for water managers and planners. As their comprehensive plan calls for development that will increase population 140% limitations of the water supply have already created problems. Suburban development has increased water-supply demands, added impervious surfaces that may have reduced groundwater recharge, and possibly caused transfers of water between basins through water distribution and sewer systems. When the county designed and built the service areas for the various communities natural watershed and water availability was not considered. At the time little wa know about the groundwater hydrology of the area.
Water availability is of particular concern in Marshall, where the Fauquier Water and Sanitation Authority (FCWSA) reported a 40 to 60 foot drop in the water levels over the past four years. Diminished water supply has left the town with inadequate water pressure despite lowering equipment and adjusting the pumping schedules. Some of the Service Districts within the County are potentially threatened by either the presence of land uses that could, or have, adversely impact groundwater quality and/or are within areas where current or future groundwater withdrawals may exceed recharge rates. According to Jamie Emery, Emery & Garrett Groundwater Investigations of the 42 inches of annual rainfall in the County, only about 6 to 10 inches contribute to groundwater recharge.
FCWSA and Fauquier County have invested more than$100 million in wells and water infrastructure throughout the county. These investments include: pump stations, pipelines, water tanks, treatment systems and more. Yet with all this money spent there has been no money spent on protecting the wells and their recharge zones. The County has not even defined the groundwater recharge areas for its existing wells. Chemical spills or leaks from fuel storage tanks can go unnoticed until they contaminate public water sources. Changes in land use can adversely impact groundwater quality. Yet the County does not have land use policies that protect and preserve its critical groundwater resources.
Unfortunately, Service Districts are not neatly overlain over the best portions of a watershed drainage area because that wasn’t the key factor in deciding the original location of those districts. In 2014 Fauquier County held a “Water Summit.” It was determined that despite a cost of about half a million dollars, Fauquier needed a study of the groundwater resources in the county. A detailed study designed by the U.S. Geological Survey (USGS) and spearheaded by the USGS and Virginia Department of Environmental Quality (DEQ) would address most of the issues and challenges to moving forward in the development of the County’s water supply and the professional management of its water resources. The County determined that there are many efficiency, cost-saving, strategic, professional, and long-term benefits to gaining a broad understanding of Fauquier County’s groundwater resources. There are also short-to-mid-term, practical and applied benefits as well.
With the implementation of the study that is to be completed at the end of the second quarter in 2021, Fauquier begins down the road to sustainable groundwater use. Honestly if the public water supply had not been dependent on groundwater the private wells in the county would have been long dry before sustainable groundwater and land use, zoning and overlay districts were managed in an informed way.