In response to increasing concern about the quality of
irrigation drainage and its potential effects on fish, wildlife,
and human health, the U.S. Department of the Interior formed an
interbureau task group to prepare a plan for investigating water-
quality problems on irrigation projects sponsored by the
Department of the Interior. The San Juan River area in
northwestern New Mexico was one of the areas designated for study.
Investigators collected water, bottom-sediment, soil, and
biological samples at more than 50 sites in the San Juan River
area during 1993-94. Sample sites included (1) sites located
within Department of the Interior irrigation project service
areas, or areas that receive drainage from irrigation projects;
(2) reference sites for comparison with irrigation project sites;
and (3) sites located within the reach of the San Juan River from
Navajo Dam to 10 miles downstream from the dam. The types of
habitat sampled included the main stem of the San Juan River,
backwater areas adjacent to the San Juan River, tributaries to the
San Juan River, ponds, seeps, irrigation-delivery canals,
irrigation-drainage canals, a stock tank, and shallow ground
water. The types of media sampled included water, bottom
sediment, soil, aquatic plants, aquatic invertebrates,
amphibians, and fish. Semipermeable-membrane devices were used
as a surrogate medium to sample both air and water in some
instances. Sample measurements included concentrations of major
ions, trace elements, organochlorine pesticides, polychlorinated
biphenyls, polycyclic-aromatic-hydrocarbon compounds, and stable
isotopes of hydrogen and oxygen.
This report presents tables of physical, chemical, and
biological data collected for the U.S. Department of the
Interior National Irrigation Water-Quality Program.
Additionally, supplemental physical, chemical, and biological
data collected in association with the Navajo Indian Irrigation
Project are presented.