Publications

No abstract available.

TAVELERS RETRACING LEWIS AND CLARKE JOURNEY to the Pacific over the past two hundred years have witnessed tre mendous change to the Columbia River Gorge and its pri mary feature, the Columbia River. Dams, reservoirs, timber harvest, altered fisheries, transportation infrastructure, and growth and shrinkage of communities have transformed the river and valley.1 This radically different...

No abstract available.

Travelers reacting Lewis and Clark's journey to the Pacific over the past two hundred years have witnessed tremendous change to the Columbia River Gorge and its primary feature, the Columbia River. Dams, reservoirs, timer harvest, altered fisheries, transportation infrastructure, and growth and shrinkage of communities have transformed the river and valley. This radically different...

In 1998, the U.S. Geological Survey sampled the Clackamas River, its major tributaries, and reservoirs to characterize basic water quality (nutrients, dissolved oxygen, pH, temperature, and conductance), water quantity (water sources within the basin), and algal conditions (biomass and species composition). Sampling locations reflected the dominant land uses in the basin (forest...

More than 33,000 salmon and steelhead died in the lower Klamath River in late September 2002 on their way to spawning areas upstream. According to the California Department of Fish and Game, the cause of death was infection by protozoan and bacterial pathogens. Two factors that may have contributed to the disease incidence are low streamflow and high water temperature. September...

Three sediment oxygen demand (SOD) measurement chambers were deployed in the Tualatin River near Tigard, Oregon, at river mile 10 in August 2000. SOD rates were calculated for three different circulation velocities during each chamber deployment. The SOD rate at each velocity was calculated from a graph of dissolved oxygen concentration versus elapsed time. An acoustic doppler current...

The occurrence, distribution, and transport of dissolved (filtered-water) trace elements in the surface waters of the Yakima River Basin were assessed using data collected between 1999 and 2000 as part of the U.S. Geological Survey s National Water-Quality Assessment (NAWQA) Program. Samples were collected at 34 sites throughout the basin in August 1999, using a Lagrangian sampling...

No abstract available.

Artificial neural network models were developed to estimate water temperatures in small streams using data collected at 148 sites throughout western Oregon from June to September 1999. The sites were located on 1st-, 2nd-, or 3rd-order streams having undisturbed or minimally disturbed conditions. Data collected at each site for model development included continuous hourly water...

Significant Findings When water is released through the spillways of dams, air is entrained in the water, increasing the concentration of total dissolved gas. Excess dissolved-gas concentrations can have adverse effects on freshwater aquatic life. The U.S. Geological Survey (USGS), in cooperation with the U.S. Army Corps of Engineers, collected total- dissolved-gas and water-temperature...

Three real-time, instream water-quality and turbidity-monitoring sites were established in October 1998 in the upper North Santiam River Basin on the North Santiam River, the Breitenbush River, and Blowout Creek, the main tributary inputs to Detroit Lake, a large, controlled reservoir that extends from river mile 61 to 70. Suspended-sediment samples were collected biweekly to monthly at...