Welcome to the

Environmental Dynamics Laboratory

University of California, Davis

In 2000, a remotely operated vehicle was deployed in Lake Tahoe to recover a thermistor chain that had sunk to the bottom at a depth of 460 m. The cause of the sinking is attributed to the loss of buoyancy in the primary flotation buoys when they were forced downwards during an extraordinarily large upwelling event in December 1999. Despite the fact that the thermistor chain was near the center of the lake (away from the highest deflections amplitudes at the boundaries) the induced currents would be highest in this region.

The video clip you will see is a record of a portion of the recovery process. Initially the ROV is motionless, and there are clouds of particles drifting by it. This cloudiness does not represent the natural state of the bottom of Lake Tahoe. It is the caused by the ROV’s thrusters having previously stirring up the bottom sediment. It does however indicate that the lake’s bottom sediments are readily resuspended by episodic high current events (such as upwellings and downwellings). When the cloudiness clears you will see the yellow articulated arm of the ROV in the foreground. In the background is a tangle of 460 m of spectrabraid rope that was used for the thermistor chain and the attached loggers.

Click here to take a look at the bottom of Lake Tahoe.