Major-Ion, Nutrient, and Trace-Element Concentrations in the Steamboat Creek Basin

In September 1996, a water-quality study was done by the U.S. Geological
Survey, in coordination with the U.S. Forest Service, in headwater streams of
Steamboat Creek, a tributary to the North Umpqua River Basin in southwestern
Oregon. Field measurements were made in and surface-water and bottom-sediment
samples were collected from three tributaries of Steamboat Creek-Singe Creek,
City Creek, and Horse Heaven Creek-and at one site in Steamboat Creek upstream
from where the three tributaries flow into Steamboat Creek. Water samples
collected in Singe Creek had larger concentrations of most major-ion
constituents and smaller concentrations of most nutrient constitu ents than was
observed in the other three creeks. City Creek, Horse Heaven Creek, and
Steamboat Creek had primarily calcium bicarbonate water, whereas Singe Creek
had primarily a calcium sulfate water; the calcium sulfate water detected in
Singe Creek, along with the smallest observed alkalinity and pH values,
suggests that Singe Creek may be receiving naturally occurring acidic water. Of
the 18 trace elements analyzed in filtered water samples, only 6 were
detected-aluminum, barium, cobalt, iron, manganese, and zinc. All six of the
trace elements were detected in Singe Creek, at concentrations generally larger
than those observed in the other three creeks. Of the detected trace elements,
only iron and zinc have chronic toxicity criteria established by the U.S.
Environmental Protection Agency (USEPA) for the protection of aquatic life;
none exceeded the USEPA criterion. Bottom-sediment concentrations of antimony,
arsenic, cadmium, copper, lead, mercury, zinc, and organic carbon were largest
in City Creek. In City Creek and Horse Heaven Creek, concentrations for 11
constituents--antimony, arsenic, cadmium, copper, lead, manganese (Horse Heaven
Creek only), mercury, selenium, silver, zinc, and organic carbon (City Creek
only)--exceeded concentrations considered to be enriched in streams of the
nearby Willamette River Basin, whereas in Steamboat Creek only two trace
elements--antimony and nickel--exceeded Willamette River enriched
concentrations. Bottom-sediment concentrations for six of these constituents in
City Creek and Horse Heaven Creek--arsenic, cadmium, copper, lead, mercury, and
zinc--also exceeded interim Canadian threshold effect level (TEL)
concentrations established for the protection of aquatic life, whereas only
four constituents between Singe Creek and Steamboat Creek--arsenic, chromium,
copper (Singe Creek only), and nickel--exceeded the TEL concentrations.

The data set checked for the concentrations of major ions, nutrients, and trace
elements in water and bottom sediments collected in the four tributaries during
the low-flow conditions of September 9-13, 1996. Stream-water chemistry results
were contrasted, and trace-element concentrations were compared with U.S.
Environmental Protection Agency chronic aquatic life toxicity criteria.
Bottom-sediment trace-element results were also contrasted and compared with
concentrations considered to be enriched in streams of the nearby Willamette
River Basin and to interim Canadian threshold level (TEL) concentrations
established for the protection of aquatic life.

The area of study was Headwater streams of Steamboat Creek, a tributary to the
north Umpqua River Basin in southwestern Oregon

Field measurements and surface-water and bottom-sediment samples at each of the
four sites included streamflow, stream temperature, specific conductance,
dissolved oxygen, pH, alkalinity, major ions in filtered water (8
constituents), low-level concentrations of trace elements in filtered water (18
elements), and trace elements and carbon in bottom sediment (47 elements).

Stream temperature, specific conductance, dissolved oxygen, and pH were
measured using a calibrated Hydrolab multiparameter unit. Because stream widths
were less than 8 feet, field measurements were made only near the center of
flow at 1 foot or less below water surface. The Hydrolab unit was calibrated
at each site before and after sampling. Stream temperatures were recorded to
the nearest 0.1 degree Centigrade; specific conductance to the nearest 1
microsiemen per centimeter at 25 degrees Centigrade ; dissolved oxygen to the
nearest 0.1 milligrams per liter; and pH to the nearest 0.1 pH units.
Measurements of streamflow were made in accordance with standard USGS
procedures (Rantz and others, 1982). Alkalinity measurements were made on
filtered water samples using an incremental titration method (Shelton, 1994),
and results were reported to the nearest 1 milligram per liter as calcium
carbonate (CaCO3). Water samples were collected using 1-liter narrow-mouth
acid-rinsed polyethylene bottles from a minimum of eight verticals in the cross
section, suing an equal-width-increment method described by Edwards and Glysson
(1988), and composited into a 8-liter polyethylene acid-rinsed churn splitter.
Sample and compositing containers were prerinsed with native water prior to
sample collection. Water samples were collected using clean procedures as
outlined by Horowitz and others (1994). Samples were chilled on ice from time
of sample collection until analysis, except when samples were processed.
Processing of the field samples was accomplished either in the mobile field
laboratory or in an area suitably clean for carrying out the filtering and
preservation procedures. Samples for major ions, nutrients, and trace elements
in filtered water (operationally defined as dissolved) were passed through 0.45
micrometer pore-size capsule filters into polyethylene bottles using procedures
outlined by Horowitz and others (1994). Filtered-water trace-element samples
were preserved with 0.5 milliliter of ultra-pure nitric acid per 250 mL of
sample; nutrient samples were placed in dark brown polyethylene bottles and
were chilled for preservation. All chemical samples were shipped to the USGS
National Water Quality Laboratory (NWQL) in Arvada, Colorado, for analysis
according to methods outlined by Fishman (1993).

The information for this metadata was taken from the Online Publications of the
Oregon District at http://oregon.usgs.gov/pubs_dir/online_list.html .