Conference Papers

No abstract available.

The Upper Animas River watershed in southwestern Colorado is located in the San Juan mountains and has been intensively mined. Active mining has essentially ceased but the impact of past mining on the aquatic ecosystem continues. This paper presents initial results from a study to determine the characteristics of the physical habitat for aquatic animals and the sediment characteristics...

A near real-time streamflow-simulation system utilizing continuous-simulation rainfall-runoff generation with dynamic-wave routing is being developed by the U.S. Geological Survey in cooperation with the Du Page County Department of Environmental Concerns for a 24-kilometer reach of Salt Creek in Du Page County, Illinois. This system is needed in order to more effectively manage the...

The Osprey population associated with Darwin Nature Reserve and the Rybinsk Reservoir increased from only a few pairs prior to the creation of the reservoir in the late 1940s , to about 45-50 pairs in 1994. Productivity rates were excellent in 1988 and 1989 (1.38 young/occupied nest), but extremely low in 1987 (0.47 young/occupied nest). A chemical spill into the Volga River in early...

This paper briefly presents pier-scour depths measured during 1943-94, that are thought to have been affected by consolidated cohesive materials (clay) in Mississippi. MDOT soil reports were available for 29 measured pier-scour depths thought to be affected by clay. The cohesion and friction angles were approximated for the clay, and using the soil borings where clay was overlain by sand...

A simulation-optimization model was developed for the optimal management of the city of Santa Barbara's water resources during a drought; however, this model addressed only groundwater flow and not the advective-dispersive, density-dependent transport of seawater. Zero-m freshwater head constraints at the coastal boundary were used as surrogates for the control of seawater intrusion. In...

Incorporating human impacts into conservation plans is critical to protect natural resources. Using a model that examines how anthropogenic changes might be proactively influenced to promote conservation, we argue that a denser human population does not spell inevitable doom for Atlantic salmon (Salmo salar). Humans affect the Atlantic salmon ecosystem deleteriously through landscape...

A method was developed by the U.S. Geological Survey for rapid estimation of scour at highway bridges using limited site data and analytical procedures to estimate pier, abutment, and contraction scour depths. The basis for the method was a procedure recommended by the Federal Highway Administration for conducting detailed scour investigations, commonly referred to as the Level 2 method...

On January 15, 1997, a landslide of approximately 100,000-m3 from a coastal bluff swept five cars of a freight train into Puget Sound at Woodway, Washington, USA, 25 km north of downtown Seattle. The landslide resulted from failure of a sequence of dense sands and hard silts of glacial and non-glacial origin, including the Lawton Clay, a hard, jointed clayey silt that rarely fails in...

No abstract available.

The Firehole River (FHR) in Yellowstone National Park (YNP) is a world- renowned recreational fishery that predominantly includes rainbow trout (RBT, Oncorhynchus mykiss) and brown trout (BNT, Salmo trutta). The trout populations apparently are closed to immigration and have been self- sustaining since 1955. Inputs from hot springs and geysers increase the temperature and mineral content...

No abstract available.