Summer Lake is a large shallow alkali lake that stretches 15 miles in length and 5 miles wide at high water. At the end of the last ice age, rain and melting snow filled the Summer Lake and Abert Lake basin creating Lake Chewaucan. The Lake was approximately 375 ft deep and covered 461 square miles. The last high-water period occurred 13,000 years ago.
Today, the lake comes and goes during wet and dry periods while the Summer Lake Basin consists of a large wetland marsh fed by Ana River. The basin is a hotspot for over 250 species of birds. The communities of Summer Lake, Silver Lake, Fort Rock, and Christmas Valley are within the Summer Lake Watershed.
