USGS Monitoring
Data
In
1996, the U.S. Geological Survey began a water-quality study of the
Cheney Reservoir watershed in participation with the city of Wichita
and the Bureau of Reclamation. The objectives of the study were to:
(1) describe differences in concentrations and transport of selected
water-quality constituents within the Cheney Reservoir watershed; (2)
evaluate, specifically, the annual transport of selected water-quality
constituents into and out of Cheney Reservoir; and (3) evaluate long-term
changes in the chemical quality of reservoir sediment to serve as a
surrogate for historical changes in water quality.
The study consisted of two general phases. Phase I components included
a short-term, preliminary evaluation of the watershed to document spatial
variability in water-quality constituents and to assist in selection
of long-term monitoring sites. Thirty-four sampling sites were monitored
during Phase I, which was conducted from June through September 1996.
These sites were sampled during periods of sustained low flow, which
is streamflow originating primarily as springflow, ground-water seepage,
irrigation return flow, or as point-source discharges such as from wastewater
treatment plants.
Results
of the Phase I evaluation identified dissolved solids and nutrients
as potential water-quality concerns during low flow and led to the establishment
of six long-term sampling sites during Phase II. Phase II consisted
of a 3-year data-collection effort to quantify water-quality constituent
concentrations and loading characteristics in selected subbasins within
the watershed and into and out of Cheney Reservoir. Phase II included
an evaluation of both low-flow and runoff periods. Water and sediment
samples were collected from several locations within the reservoir.
Data
from this study supports the initial concerns of the project but it
also provides a clearer picture of the sources and transport of these
pollutants within the watershed. Reports from the USGS studies are available
at their web site, http://ks.water.usgs.gov/Kansas/qw/cheney/.
