LAKE LAHONTAN (Nevada and California)

An ancient Ice Age lake which covered an extensive portion of northwestern Nevada during the last Glacial Epoch, a period when the Great Basin was covered with a considerable number of lakes and rivers. Lake Lahontan, along with Lake Bonneville far to the east, represented the major Ice Age lakes which covered vast portions of Nevada and Utah and provided a far more lush and hospitable environment for both flora and fauna. Now, only the Great Salt Lake remains to provide an indication of the prehistoric presence of Lake Bonneville, and only Pyramid Lake and Walker Lake remain to provide testament of the presence of Lake Lahontan. In its day, Lake Lahontan would cover some 8,655 square miles in northwestern Nevada, an area equal to almost 8 percent of Nevada's present surface area. This Ice Age lake was fed by the flows of the Truckee, Carson, Walker, Humboldt, Susan and Quinn rivers, attained a maximum surface elevation of approximately 4,380 feet, reached a maximum depth of at least 886 feet where Pyramid Lake, the lowest point in the system, now remains, covered the Lahontan Valley Wetlands (Stillwater Wildlife Refuge) to a depth of 500-700 feet, stretched from just below Nevada's northern boundary to Walker Lake, and extended well up the lower Truckee Canyon towards the city of Reno to near the present-day location of Lagomarsino Canyon near Lockwood. Lake Lahontan experienced at several peaking enlargements: approximately 65,000, 45,000, 30,000, and as recently as 12,500 years ago: and at times nearly dried up.