CHARACTERIZING GROUNDWATER SEEPAGE IN THE HEADWATERS OF THE WHITE RIVER, MANISTEE NATIONAL FOREST, MICHIGAN

Groundwater discharge sustains the White River, located in Manistee National Forest, Michigan. In a headwater reach of the White River, conduit discharge of groundwater is visible in the streambed. During the summer of 2013, streambed seepage was quantified to better define the interaction between groundwater and surface water. Two seepage meters, modified for this setting, were deployed at several locations in the stream, including both conduit spring discharge and diffuse discharge sites. Four large conduit springs, of eleven observed, discharged an average of 1.19 liters per minute. Many smaller conduits were also observed throughout the streambed. Seepage rates in diffuse discharge sites ranged from 4.5 X 10^-4 to 1.2 X 10^-2 liters per minute. The conduit spring sites discharge groundwater at a rate two to four orders of magnitude greater than diffuse sites. Stream discharge is generally stable and averaged approximately 42,000 liters per minute during the period of study. In addition to seepage data, measurements of QW field parameters were taken in discharging “spring” water and in overlying surface water. Using a continuously monitoring data logger, measurements of groundwater head, temperature, and specific conductivity of “spring” water were collected. The data show discharging groundwater with consistently higher specific conductivity and lower temperature. Groundwater measurements were relatively constant, with a mean specific conductivity of 0.33 ms/cm, a mean temperature of 9.12 degrees Celsius, and a mean pH of 6.38; surface water measurements were variable. Observations show the White River gaining chemically and thermally stable groundwater from uniquely specific areas of high discharge.