7983

• UCREFRP Catalog Number: 7983
• Author: U.S. Department of the Interior.
• Title: Quality of Water, Colorado River Basin.
• USFW Year: 1993.
• USFW - Doc Type: Progress Report No. 16,
• Copyright Material: NO

x Definitions of Terms

centimeter at 25 oC. Specific conductance is
related to the type and concentration of ions in
water and can be used to estimate salinity or the
dissolved solids content ofthe water.

Streamflow is the discharge of water that
occurs in a natural channel.

Suspended sediment is the sediment that at
any given time is maintained in suspension by
the upward components of turbulent currents or
that exists in suspension as a colloid.

Total dissolved solids (TDS) is the total
amount of dissolved material, organic and
inorganic, contained in water. The actual
measure of TDS may be made using numerous
methods: evaporation at 105 oC, evaporation at
180 oC, or sum of ionic constituents (less some
portion of the bicarbonate fraction). The method
currently used, sum of constituents less
approximately half of the bicarbonate fraction, is

considered, by the U.s. Geological Survey to be
consistent with measurements made using the
180 oC evaporative technique.

Total salt load is the total quantity (mass) of
dissolved solids passing a given point during a
given time. The load is calculated as a function
of concentration and discharge.

Transbasin diversion is the total amount of
water diverted out of the Colorado River Basin.

Virgin flow is the historical flow at the point of
measurement corrected for the effects of
manmade developments in the drainage basin
above the point of measurement.

Water year is the 12-month period, October 1
through September 30. The water year is
designated by the calendar year in which it ends
and which includes 9 of the 12 months.

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