Groundwater is invisible to us. The expression “Out of sight, out of mind” is sometimes used when a friend or loved one is away. But according to an article in the September issue of “Water Resources IMPACT”, the expression can also be applied to groundwater. The authors state that “This lack of physical visibility has contributed greatly to its lack of visibility in many discussions of water policy, governance, and management.”
Worldwide, groundwater is extremely important. Only three percent of the water on earth is fresh and two of the three percent is tied up in the Antarctica and Greenland icecaps. Of the remaining one percent of freshwater, 99 percent is groundwater and only one percent is surface water including all the freshwater rivers and lakes.
Groundwater occurs from near surface to several hundred feet below land surface. Shallow groundwater is the most susceptible to contamination Contaminants may include fertilizer both natural and manufactured, naturally occurring trace constituents, leakage from treatment plants or septic systems, pesticides, household chemicals, fracking chemicals, gasoline or fuel oil spills, and leading underground storage tanks. Even road salt can be a potential groundwater contaminant. Contaminants may reach groundwater by infiltration, through abandoned wells, for even around poorly installed existing wells
The Alley article states that in the United States, about 38 percent of the population depends on groundwater for its drinking water supply. Rural areas often are 100 percent dependent on groundwater.
Locally, Middleburg’s water supply is totally from groundwater. Two wells on Salamander property, one well about two miles south of town and two wells inside the town limits comprise the water supply. The area is not blessed with abundant groundwater. The subsurface geology is complicated and there is not a single aquifer underlying the area. Because of this, drinking water sources can be limited.
The article provides suggestions for groundwater management that include the following:
Governing and managing groundwater require working with people
Data and information are key
Groundwater and climate are linked
We need to take care of what we have
Effective groundwater management is adaptive and resilient to drought and climate change
Agriculture, energy, environment, land use planning and urban development policies must incorporate groundwater considerations
Middleburg aggressively manages its drinking water supply. The Middleburg Wellhead Protection Advisory Committee comprised of local residents provides recommendations to the Town Council for management and protection of the source water. Based on the committee’s recommendation, the council determined that a reasonable protection area for each well is a one mile radius. Because the radii overlap, the entire town is included in the source water protection area.
Middleburg does an excellent job of protecting its source water. Potential areas of contamination are closely monitored. Potential contaminants such as bacteria, lead, copper, nitrate, radiological constituents and others are regularly measured and are within acceptable limits.
Most of the suggestions from the Alley article have already been incorporated into Middleburg’s source water protection plan. Still, the citizens of Middleburg must continue to practice water conservation and limit potential sources of contamination.
Reference: Alley, W. M. and others, 2016, “Making Groundwater Visible”, American Water Resources Association, Water Resources IMPACT, Volume 16, Number 5.