GROUND WATER IN NORTH-CENTRAL TENNESSEE

MONTGOMERY COUNTY 165
and most of the wells heretofore drilled to it for industrial water supply
have been abandoned as inadequate. Hence it does not constitute
a promising source of water in other parts of the county.
The most reliable sources of water in many parts of the county are
the tufctolar springs (pp. 92-95), which issue from solution channels
in the limestone. Such springs are especially numerous in the north-
central part of the county, in the vicinity of the converging forks of
the Red River and of the meandering portion of the course of the Cum­
berland River. The largest and least variable of the springs issue
from channels that are approximately adjusted to the present erosion
stage of the principal streams and are essentially tributaries of the
regional drainage system. Some issue from channels that probably
join converging tributaries or the limbs of stream meanders and hence
they may have a large and relatively invariable discharge, even though
they do not drain large bodies of limestone. Two springs in Mont­
gomery County, Nos. 43 and 44 (p. 168), are known to discharge more
than 1,000 gallons a minute and many others discharge 100 gallons a
minute or more. The discharge from a tubular spring may fluctuate
greatly, so that the maximum safe draft can be determined only by
periodic measurements during several years.
Most of the ground waters from the St. Louis limestone and Warsaw
formation in Montgomery County are only moderately concentrated
and, except for moderate carbonate hardness, are satisfactory for all
ordinary uses. A few of the waters from these formations and others
from the underlying Fort Payne formation, however, are highly con­
centrated, have much noncarbonate hardness, and are unsatisfactory
for some purposes. Analyses of representative ground waters are
tabulated on pages 110-111.