RESEARCH· ·1970·

GEOLOGICAL SURVEY RESEARCH 1970
GROUND WATER-SURFACE WATE'R RELATION
DURING PERIODS OF OVERLAND FLOW
By JAMES F. DANIEL; LOUIS W. CABLE,
and RONALD j. WOLF, Indianapolis, Ind.
Abst·raot.-The ground-water exchange mechanism at the
stream interface during periods of overland runoff was investigated
by means of obse.rvation wells installed in the :flood plain
on the White River near Noblesville, Ind. Ground-water discharge
decreases with the beginning of a stream rise, ceases
nfter n short time interval, and then bank storage occurs. A
volume of discharge from the aquifer equal to that which
entered as bank storage at the study site was dissipated 54
hours after an overbank peak, 42 hours after a medium peak
and 50 hours after a small peak. The results were used to
formulate a theoretical method for stream-hydrograph separation
of base flow and overland flow. The separation method
shows no ground-water runoff until bank storage and channel
storage volumes have been dissipated. All discharge in the
stream before and after this period is equal to that contributed
hy the aquifer system.
In the course of a recent water-resources investigation
in Indiana, it was desirable to separate streamdischarge
hydrogra phs into overland runoff and baseflow
components. The principal problem was what
occurs when the stream level rises rapidly owing to
floodflow. flow, then, should the stream-discharge
hydrograph be separated~ A search of the available
literature on the subject found numerous methods, none
of which seemed to deal satisfactorily with floodflow
conditions. To answer this question it was necessary to
acquire a better understanding of the reaction of the
subsurface flow system to a rise in stream level. Pogge
( 1966) has reported some significant information concerning
the relation of surface and subsurface flow
systems, and. Cooper and Rorabaugh (1963) have described
the theoretical reaction of ground-water levels
to a symmetrical flood pu~se when and where the initial
ground-water levels were horizontal.
A limited research project was designed to investigate
the mechanism of ground-water discharge at the
stream interface and to develop a method for analyzing
ground-water runoff. To accomplish this it was necessary
to: (1) observe the reaction of ground-w:ater
levels to fluctuations in stream level, (2) determine
from these observations the direction of ground-water
movement as it changes with time, and ( 3) relate these
data to the stream-discharge hydrograph.
Acknowledgment.-Special thanks is extended to
1\ir. Tom Benefiel for permission to install observation
wells on his property in the course of the investigation.
SITE SELECTION A!ND WELL rNSTALLATION
A field site was chosen on the White River adjacent
to the U.S. Geological Survey stream-gaging station,
between Cicero and Strawtown, near Noblesville, Ind.
(fig. 1). At the site the alluvium is composed of sand
and gravel capped by a layer of silt and clay about
6 to 7 feet thick. The potentiometric level in the sand
and gravel is usually above the base of the silt-clay
layer so that artesian or leaky- artesian conditions gen-
•
Gaging station
.3
Observation well and number
0 2000 FEET
FIGURE 1.----Study area location and site sketch.
U.S. GEOL. SURVEY PROF. PAPER 70G-B, PAGES B99-B223 ·
B219
372-490 0- 70- 15