GROUND WATER IN NORTH-CENTRAL TENNESSEE

SUMNEE COUNTY 208
Gallatin are known to exist in the adjacent parts of the county, so that
the water-yielding capacity of the rocks at the level of the river is
not known.
MUNICIPAL GROUND-WATER SUPPLIES
Portland. The only municipal ground-water supply in Sumner County is that
of Portland (population 1,030), which derives its water from Cold Spring (No. 115,
p. 206) and from another tubular spring about a quarter of a mile to the east.
These springs, which are about 2 miles northeast of Portland and about 100 feet
below the level of the Highland Rim peneplain in that vicinity, issue from solution
channels along bedding planes in the St. Louis limestone or the Warsaw formation.
Other springs and solution channels at approximately the same altitude indicate
that the conduits of the municipal springs are parts of a system of channels that
probably drains a rather extensive area of the peneplain. The discharge of the
two springs in October, 1927, when the ground-water discharge was approximately
the minimum for the season, was about 150,000 gallons a day; the maximum
discharge of the springs is not known. At each orifice are a covered cut-off trench
lined with concrete, suitable collecting mains, and a pump with a capacity of
100 gallons a minute. These pumps force the water directly into the distribution
mains, in which the pressure is equalized by a 150,000-gallon elevated steel tank
near the center of the town.