A collaborative project prevents flooding while recovering important culture resources

Donner Lake Outlet Dredging

With collaboration, transparency, and creative, solution-oriented engineering, we helped to avert flooding and recover a trove of cultural artifacts. When rain and snow in California helped relieve four years of drought in the Lake Tahoe region, it raised water levels at Donner Lake near Truckee within one foot of flooding properties around the lake. To reduce the threat of flooding, dredging was necessary at the lake’s outlet dam. Our role was to guide the permitting process, which required coordination across nine federal, state, and local authorities, as well as with two Native American tribes—the Washoe Tribe of Nevada and the United Auburn Indian Community in California.

Ultimately, the dredging process removed 6,200 cubic yards of sediment—equal to approximately 620 truckloads. We invited the Native American tribes to collaborate early in the process and they provided valuable technical advice regarding what would prove to be a 10,000-year-old prehistoric site. Consulting closely with the tribes, we used a variety of archaeological solutions to recover historic artifacts in the removed sediment. Mechanical and manual sediment screening resulted in the recovery of 5,315 historic items, including 450 prehistoric flaked stone tools, and 28 ground stone tools.

With permitting fast-tracked in less than three months, flooding was averted, artifacts recovered, and the fascinating deeper history of the area’s first inhabitants revealed.