In this study, scenarios testing different dam-operation strategies and hypothetical dam-outlet structures were simulated using CE-QUAL-W2 hydrodynamic/temperature models of the Middle Fork Willamette River system from Hills Creek Lake to Lookout Point and Dexter Lakes to explore and understand the efficacy of potential flow and temperature mitigation options.
Model scenarios were run in constructed wet, normal, and dry hydrologic calendar years, and designed to minimize the effects of Hills Creek and Lookout Point Dams on river temperature by prioritizing warmer lake surface releases in May August and cooler, deep releases in September December.
Each year, summer releases from the dams typically are cooler than pre-dam conditions, with the reverse (warmer than pre-dam conditions) occurring in autumn.
If you take a thin board and bend it with your hands (Figure 3-1, right), the board will deform.
The problem is that earthquakes start out many miles beneath the surface, too deep for us to observe them directly.
So we study them from afar by (1) observing the geological changes at the ground surface, (2) analyzing the symphony of earthquake vibrations recorded on seismographs, and (3) monitoring the tectonic changes in the Earth’s crust by surveying it repeatedly, using land survey techniques for many years and now using satellites.
Artifacts include birdstones, blocked-end smoking pipes, boatstones, cord-marked pottery, engraved stone tablets, and hammerstones.
The earliest known are Solutrean points of the Upper Palaeolithic.