Maryland springs - their physical, thermal, and chemical characteristics
1985, Otton, E.G. and Hilleary, J.T.
Report of Investigations 42
This report describes the investigation and appraisal of the flow and temperature of 100 springs in a 4,500- square-mile area comprising the Piedmont and Appalachian provinces of Maryland. The flow of these springs ranges from less than 1 to nearly 10,000 gallons per minute. The largest flow is from the Potomac Blue Spring in the Potomac River valley near Cumberland, Maryland. The flow of most springs ranges widely throughout an annual cycle, in some instances by as much as two orders of magnitude. All but 1 of 26 springs would be classed as variable to subvariable, according to a variability index proposed by Meinzer.
Temperatures of 76 Maryland springs were measured through an annual cycle. Variations at individual springs ranged from 1.5 to 18.9 degrees Celsius (0C). The maximum temperature recorded was 19.9°C. Mean annual water temperature is usually within 1 ° to 2°C of the mean annual air temperature at the locality. The lowest mean temperatures generally occur in the highland areas of Garrett County, while the highest temperatures occur in southern Montgomery County. Measurements of flow and temperature of a large spring in Washington County show that an energy transfer involving a reduction of its mean temperature by 5°C would yield 1,320,000 watts per hour. Other springs of comparable flow and thermal characteristics are in Washington, Frederick, and Allegany Counties. Therefore, Maryland springs represent a large potential source of thermal energy.
Chemical analyses of the water from 24 springs show that most of them have calcium-magnesium bicarbonate type water, or water of a mixed type. Nearly all the water is of a chemical character suitable for most uses, although water from limestone springs is hard to moderately hard . Concentrations of the trace elements aluminum, cadmium, chromium, copper, lead, lithium, mercury, nickel, silver, and lead are all below the U.S. Environmental Protection Agency's maximum allowable contaminant levels.