Infiltration and quality of water for two arroyo channels, Albuquerque, New Mexico, 1988-92

Selected reaches of Grant Line Arroyo and Tijeras Arroyo in
Albuquerque, New Mexico, were studied to collect information
about the amount and quality of infiltration through arroyo
channels. Infiltration rate was calculated for selected reaches
of Grant Line Arroyo and Tijeras Arroyo based on instantaneous
streamflow-loss volumes, wetted channel area, and instantaneous
evaporation rates measured during 1988-92. Infiltration rates at
Grant Line Arroyo ranged from 0.0 to 0.6 foot per day, and at
Tijeras Arroyo from 2.28 to 30 feet per day. The evaporation
rate ranged from one-tenth of 1 percent to 2 percent of the
infiltration rate.

Infiltration rates differed with the location of the reach
isolated for measurement and with the time of day of the
infiltration-rate measurement. Differences in intrinsic
permeability of the sediments may be the most important factor
affecting spatial variations in infiltration. The most important
factor affecting temporal variations in infiltration may be the
temperature of the water and sediment where infiltration occurs.

Annual evaporation rates were greatest over saturated stream
sediments and ranged from 802 to 1,025 millimeters per year or
from 31.57 to 40.35 inches per year. Annual evaporation rates
were least over unsaturated, unvegetated soil and ranged from 174
to 291 millimeters per year or from 6.85 to 11.46 inches per
year. Annual evapotranspiration rates over grasses or shrubs or both
were about one-half the rates over saturated stream sediments.
Rates were similar for Grant Line and Tijeras Arroyos. The land-
surface vegetation, availability of water at the land surface,
availability of energy to enable a change of state from water to
vapor, existence of a vapor concentration gradient, and a
turbulent atmosphere to carry the vapor away may be the factors
that determine the amount of evaporation and evapotranspiration.

Water in Grant Line Arroyo and Tijeras Arroyo met U. S.
Environmental Protection Agency drinking-water regulations for
nitrate, volatile organic compounds, dissolved lead, and
dissolved and total arsenic, barium, cadmium, chromium, copper,
iron, silver, zinc, selenium, chloride, and sulfate
concentrations. Total lead concentration in one sample from
Tramway Floodway Channel, a tributary to Tijeras Arroyo, was 55
micrograms per liter, exceeding the Environmental Protection
Agency drinking-water regulation of 50 micrograms per liter.
Dissolved-solids concentrations calculated from the sum of
cations and anions usually exceeded the Environmental
Protection Agency drinking-water dissolved-solids
regulation of 500 milligrams per liter at Tijeras Arroyo above
Four Hills Bridge.