Seepage tests on No Name Creek, Colville Indian Reservation, Washington, May 12-13, 1977

To gain information for a water-management situation, a seepage test was performed on May 12-13, 1977, on a reach of No Name Creek on the Colville Indian Reservation in north-central Washington. On May 13, injection of a concentrated brine at the head of the test reach permitted chloride-concentration data to be combined with the discharge measurements made to define the pattern of gain and loss along the reach. Equations describing discharge and chloride mass balance were used to determine this pattern of gain and loss. The seepage tests showed that the streamflow gain of at least 0.58 cfs from springflow contributions was offset by losses of at least 0.59 cfs over the same reach. (Woodard-USGS)