Digging into Redmond’s past: Archeologist, team discover 10,000-year-old stone tools underneath peat along Bear Creek

Redmond resident Gene Schaffer, who minored in anthropology in college, often wonders what his city and the greater Seattle area looked like in the past.

Redmond resident Gene Schaffer, who minored in anthropology in college, often wonders what his city and the greater Seattle area looked like in the past.

“I wish there was ways I could turn back the clock a mere 200 years to see what it was like, because this (Redmond) was all solid trees and undeveloped… but we just looked at something from 10,000 years ago,” he said.

As he exited the Old Redmond Schoolhouse Community Center auditorium last Saturday, Schaffer’s eyes widened a bit as he discussed the presentation he just witnessed by Dr. Robert Kopperl, a veteran archeologist who works for SWCA Environmental Consultants.


In front of a packed house of about 275 people at the Redmond Historical Society’s Saturday Speaker Series, Kopperl dug into his lecture about he and his team discovering more than 4,000 stone artifacts — including tools, flakes, scrapers, spear points and more — in 2009 and 2013 underneath peat along Bear Creek during the city’s salmon restoration project. It is a site where arrowheads and other hunting tools were made some 10,000 years ago.

“It is the oldest archeological site with stone tools that has so far been investigated by archeologists in the Puget Lowlands and the Washington Straits region,” Kopperl told the crowd. In an earlier report, Kopperl noted that the site is the first opportunity to study how American Indians made the Puget Lowlands their home at the end of the last ice age, some 16,000 years ago.

Mayor John Marchione told the crowd that the City of Redmond and its partners planned and worked to complete the rehabilitation of the lower Bear Creek since 1990. The 3,000-foot project near State Route 520 was relocated from a mostly straight, channelized stream to a meandering run to support healthy and diverse fish fronts, including the largest wild Chinook salmon population in the Sammamish basin.

Kopperl noted that their discovery happened during a routine environmental compliance  project for the city to survey the waterways and the site.

“We were thrilled by the significance of this discovery that teaches us about Redmond’s Native American heritage,” Marchione said.


When they began the cultural resource survey in 2008, Kopperl said they knew they had a good chance of finding artifacts because they were working near Marymoor Park, a site where American Indian archeological evidence was found that dates back 5,000 years or more.

The team’s survey protocol consisted of using a combination of digging by hand with brushes and trowels and also utilizing backhoes.

“We had to find a balance of being able to get down into those deeper older sediments, and try to get down to all the cobbles and gravel that was laid down when the glaciers moved back when they were treated at the end of the ice age,” Kopperl said.

Kopperl said while finding the artifacts is exciting, it’s the sequence of dirt in which they’re found that is interesting, as well. The team discovered a dirt layer cake consisting of sand (alluvium) at the top, a thick layer of diatomaceous earth and then peat on the bottom. In one of the two digs, they found a thin sandy layer below the peat and above the glacial outwash.

As far as how deep the archeologists dug, Kopperl could only reveal that “the creek rehabilitation project involved excavating the new channel about eight feet below the floodplain, and our work was conducted within the depth of ground disturbance,” in a follow-up email to the Reporter.

In one dig, the peat was radiocarbon-dated to about 9,000 years old, and when they found artifacts — including the tip of a projectile point — below the peat and above the glacial outwash in the next dig, Kopperl told city officials they might be 10,000 years old or more. Luminescence dating at a University of Washington lab also corroborated their radiocarbon dating.


When Kopperl and his team  — who dug 425 square meters — found artifacts, they handled them with gloves and placed them in foil to be sent to a lab for protein and residue analysis. One of the tools had the remains of animal residue on it, possibly bison, bear, deer, elk or sheep.

Kopperl said most of the artifacts they found were made from different kinds of metamorphic rock, and volcanic rock such as basalt. A smaller number of artifacts found at the site were made of chert and quartz and make more durable and sharper cutting tools.

To Kopperl’s delight, they found one bone that has the shape and texture of a salmonid fish. He didn’t think it was possible they would find a bone because of preservation conditions.

The City of Redmond and Kopperl’s team worked closely so that the city could complete its project on time and give the archeologist and crew room to dig and preserve history. There was also a legal obligation for the city to consult with the Snoqualmie, Muckleshoot, Stillaguamish and Tulalip tribes under federal law. Additionally, cultural resources representatives of the Muckleshoot and Snoqualmie tribes worked closely with the city and other government agencies to ensure that portions of the site were either protected or studied.

The artifacts are still being analyzed in a Seattle lab, and when that process is completed, Kopperl said the Muckleshoot tribal facility may put the tools on display.

Kopperl and crew also found a few other artifacts and charcoal at the site, but nothing as significant as the stone tools. They were hoping to find the remains of structures like tents or campfire sites, but those relics weren’t located.

Redmond resident Marie Healy said she found it interesting to get a glimpse into the far distant past and the people who inhabited the area.

“You find pictures in your mind of, ‘What were they doing?’ I feel this showed us a little bit. I hope they (do) further diggings and (find) information that can tell us more about the people,” she said.

During the end of Kopperl’s presentation, one man in the crowd barked, “Keep digging — you’ll find the Redmond Man and Redmond Woman,” in reference to Kennewick Man, the skeletal remains of a prehistoric Paleoamerican man found on a Columbia River bank.