Streamflow gain/loss in the Republican River Basin, Nebraska, October 1998

This data set was created to archive the calculated stream flow gains and
losses of streams in the Republican River Basin, Nebraska, in October 1998, and
make the data available for use with geographic information systems (GIS).

This arc and point data set contains stream flow-measurement sites and reaches
indicating stream flow gain or loss under base-flow conditions along the
Republican River and tributaries in Nebraska during October 25 to 28, 1998
(Boohar and others, 2000). The stream flow measurements were made to obtain
data on ground-water/surface-water interaction. Flow was observed visually to
be zero, was measured, or was estimated at 374 sites. The measurements were
made on the main stem of the Republican River and all flowing tributaries that
enter the Republican River between Swanson and Harlan County Reservoirs in the
Nebraska part of the Republican River Basin. Tributaries were followed upstream
until the first road crossing where zero flow was encountered. Measurements
also included estimates of average wastewater discharge during the period when
the flow measurements were made, based upon data obtained from towns having
measurable wastewater discharge. For selected streams, points of zero flow
upstream of the first zero flow site also were checked.

Stream flow gain or loss for each stream reach was calculated by subtracting
the stream flow values measured at the upstream end of the reach and values for
contributing tributaries from the downstream value. The data obtained reflected
base-flow conditions suitable for estimating stream flow gains and losses for
stream reaches between sites. However, due to fluctuations in stream flow on
the main stem of the Republican River above Swanson Reservoir during the
measurement period, flow measurements on the main stem could not be used for
calculating reach gains and losses. Flows measured on tributaries to the
Republican River above Swanson Reservoir were of suitable quality to use for
stream flow gain/loss calculations. Flows on Sappa Creek did not reflect
base-flow conditions and thus were not suitable for investigating
ground-water/surface-water interaction.

This digital data set was created by manually splitting the lines from a
1:250,000 hydrography data set (Soenksen and others, 1999) at every stream
flow-measurement site. Each set of stream segments between measurement sites
was assigned a unique reach number.

This digital data set was created by manually plotting locations of stream flow
measurements. These points were used to designate steam-reach segments to
calculate gain/loss per river mile.

Reach segments were created by manually splitting the lines from a 1:250,000
hydrography data set (Soenksen and others, 1999) at every location where the
streams were measured. Each stream-reach segment between stream flow
measurement sites was assigned a unique reach number. All other lines in the
hydrography data set without reach numbers were omitted.