Lably
Skip to content

Summer Lake (Oregon)

  • 3 min read
  • 4 chapters

Related on Lably

Through Lake and Hunting

Ancient Lake Chewaucan

The arid lands around Summer Lake were once lush. During the Pleistocene Epoch, vast areas of this region of south central Oregon were covered by lakes and wetlands. As the last ice age was ending, rain and runoff from melting snow filled the lowlands throughout this region of the Great Basin, creating an immense, freshwater lake called Lake Chewaucan. The lake covered 461 square miles (1,190 km2) at depths of up to 375 feet (114 m).

Lake Chewaucan covered the Summer Lake basin and drainage system much of the late Pleistocene. The last high water period is thought to have occurred about 13,000 years ago. There is archaeological evidence of human use of Lake Chewaucan during this time. The oldest known human remains in the Western Hemisphere come from the Paisley Caves, wave-cut caves currently 10 miles southwest from Summer Lake. Lake Chewaucan began to dry up at the close of the Pleistocene. As it shrank, salts and alkali were concentrated in its remaining waters. The exposed lake bottom sediments were blown by the prevailing westerly winds to form the sand dunes that still lie on the east side of Summer Lake.

Today, Summer Lake and Abert Lake are separated by 20 miles (32 km) and are the only remnants of Lake Chewaucan. At high water, Summer Lake is about 15 miles (24 km) long and 5 miles (8 km) wide; however, water levels fluctuate dramatically, and sometimes the lake is almost dry in summer. The main source of fresh water is the small spring-fed Ana River, which is used for irrigation.

Sign in to keep reading

3 more chapters are free with a Lably account.

More in Geography