GROUND WATER IN NORTH-CENTRAL TENNESSEE

214 GROUND WATER IN NORTH-CENTRAL TENNESSEE
Estimated minimum daily discharge of springs constituting municipal water supply
at Franklin, Tenn.
No. on
Plate 4
366
379
380
381
382
383
384
384
384
386
Name
Stlllhouse Spring _______________
Spring (11 springs).
ner Springs (3 springs).
Green Spring
Goodjine Spring __________ .. _ .....
Silver Spring _________________
Location
Dobbins Branch of Leipers Fork.....
do .
north branch of.
.....do . . ..
.....do . .............................
.....do... ..............................
.....do ................. ...........
. __ do................... ...........
.....do..... .... .............
_do -. -. -
... ..do ............ ...... ..........
Garrison Branch of Leipers Fork,
south branch of.
. .do . ..... .......
.....do . . ...... ........
... . .do ....... . ... ..... .......
.....do.... .
Bally
discharge
(gallons)
26,000
40,000
21,000
16,000
16,000
3,000
12,000
8,000
5,000
8,000
4,000
21,000
53,000
8,000
4,000
29,000
273,000
This estimate, however, seems to be based upon measurements made in only
one season, 1922, in which the surface-water and ground-water discharge in
central Tennessee were much more than the average. For example, the run-off
from the Cumberland River Basin above Nashville in the year ending September
30, 1922, was 28.37 inches, whereas the average run-off in the 20-year period
ending September 30, 1924, was 22.68 inches and the minimum run-off in the
same period only 12.40 inches." Hence, the estimates tabulated above may
be more than twice the minimum discharge of the springs in an unduly dry year.
Each of the 36 springs that constitute the source is provided with a suitable
cut-off box and discharge pipe connecting with an 8-inch cast-iron pipe which
discharges by gravity into a 100,000-gallon steel standpipe and a 500,000-gallon
covered concrete reservoir on a hillside about 2J4 miles southwest of Franklin
and 130 feet above it. Distribution is effected by gravity, the maximum domestic
pressure being about 50 pounds to the square inch. The average daily consump­
tion is reported to be about 125,000 gallons, to supply which the entire discharge
of the source is utilized during the summer and autumn of unduly dry years.
Hence, some addition to the supply will perhaps become imperative in dry years
if the population of the city should increase. In view of the small tested capaci­
ties of wells drilled in the limestone in the vicinity of Franklin and of the inferior
quality of the deeper ground water, it is not certain that a material addition to
the supply can be obtained by drilling wells. Rather, such an addition should
be sought first in other springs along the flank of Duck River Ridge and second
in surface water from the Harpeth River or some of its tributaries.
Hillsboro. Most of the residents of Hillsboro (formerly Leipers Fork; estimated
population 375) derive their domestic water supplies from individual dug wells.
One group of eight dwellings, however, is supplied from a small perennial spring
through a distribution system owned and operated in cooperation by the residents.
" Bang, W. R., Water resources of Tennessee: Tennessee Div. Geology Bull. 34, pp. 129-132,1925.