no.2 Tualatin Community Park
If you’re with children, you might want to make your first stop the playground. Here ice age history and fantasy play meet in a fun learning experience. Try the interactive sandbox/water feature, which allows kids to create their own "floods," creating a miniature version of this flood-shaped landscape. Notice the erratic rocks and sculptured fossils in the sandbox channel—reminders of the erratics and fossils found throughout the Tualatin area.
West of the playground, check out the interpretive panel showing a photograph of downtown Tualatin covered under several feet of water during the floods of 1996. As destructive as these floods were, they’re miniscule compared to the Lake Missoula Floods that covered Tualatin under almost 300 feet of water.
Tualatin River bend
For example, here at the park, the river turns 90 degrees, its course bent by a tall gravel hill in Durham to the northeast. Lake Missoula floodwaters created that hill, gouging rock from the narrow gap at Lake Oswego and then dropping it in a pile measuring 200 feet high. Gravel has been extracted from this flood deposit for over 100 years, barely making a dent in the amount the floodwaters left behind.
Bones from a Harlan’s Ground Sloth were discovered near the confluence of Tualatin and Fanno Creek, close to the Ki-a-Kuts Bridge on the river’s north side. In the late 1960s or early 1970s, during the construction of the Durham Wastewater Treatment plant, worker Ernest Rowland spotted some bones in the muck of an excavation. He took them to Portland State University to be identified, where they were thought to be mastodon bones. Rowland later sold the bones to Dr. Robert McDonald, a chiropractor, who donated them in 2008 to the Tualatin Historical Society.
In 2010, a Portland State University anthropology graduate student named Danny Gilmour saw the bones and suspected they were from a ground sloth, not a mastodon. He sent photos to Dr. Greg McDonald, a National Park Service expert on ground sloths. Gilmour’s suspicions were confirmed: they were the sacrum and vertebrae of a Harlan’s Ground Sloth. You can see the bones on display at the Tualatin Heritage Center (tour stop #1).