The Pueblo of Isleta and the New Mexico Environment Department
have established water-quality standards for the Rio Grande,
which flows through Albuquerque, New Mexico. Trace-element
concentrations historically have been greater than maximum
permissible concentrations allowed by these standards. It is not
known if these concentrations are due to sources from the
Albuquerque metropolitan area or are from natural or other
sources outside Albuquerque.
Accurate water-quality data with lower reporting limits than
have been previously available were collected, and instantaneous
concentrations and loads were calculated for trace elements and
other constituents in the Rio Grande during high-flow and low-
flow conditions. Seven sampling sites were selected upstream
from, in, and downstream from metropolitan Albuquerque.
Concurrent streamflow measurements were made at the time of
sampling to determine suspended-sediment loads. Samples were
analyzed separately for trace elements dissolved in water (less
than 0.4 micrometer in diameter) and for those contained in
suspended sediment (greater than 0.1 micrometer in diameter).
Sample collection and processing, analytical methods, and quality
control are discussed.