USGS Northern Rocky Mountain Water Quality Assessment
address water resources protection at a national level, Congress
appropriated funds in 1986 for the USGS
to begin a pilot program in seven project areas to develop and refine
the National Water Quality Assessment (NAWQA)
Program. In 1991, the USGS began full implementation of the program.
The NAWQA program builds upon an existing base of USGS water quality
studies as well as those of other Federal, State and local agencies.
The objectives of the NAWQA program are to:
- Describe current water quality conditions for a large part
of the Nations’ freshwater rivers and aquifers;
- Describe how water quality is changing over time;
- Improve understanding of the primary natural and human factors
that affect water quality conditions.
The Northern Rockies Intermontane Basins (NROK)
study area (which includes areas in eastern Washington, northern
Idaho and western Montana) is one of 59 study units selected by
the USGS for full-scale implementation of the NAWQA program. The
NROK study area includes the Spokane Valley Rathdrum Prairie (SVRP)
Aquifer. Biological (Maret and Dutton, 1999), hydrological and hydrogeological
(on-going) studies of the SVRP Aquifer area are planned within the
NROK study area.
In 2000, 18 wells were drilled by the USGS within 0.6 miles of
the Spokane River between Post Falls, Idaho and Harvard Bridge near
Spokane, Washington. These wells, and an additional 7 wells drilled
for Ecology and Spokane County, were sampled 8 times from August
2000 to August 2001. Samples were analyzed for major ions, trace
elements and stable isotopes (oxygen / deuterium). Ten of the wells
were instrumented with continuous data loggers that recorded temperature
and pressure. Continuous measurements of temperature, stage and
specific conductance were also recorded at the USGS gage on the
Spokane River at Post Falls. Elevations of the wells and elevations
along cross sections of the river channel were surveyed. This data
will be summarized and interpreted in a USGS Water Resources Investigations
Report. The USGS data and results (if available) will be incorporated
into the water resources management model for WRIA 57.
Terry Maret (208)
387-1328 -or- Dorene MacCoy