Willamette River

About

Willamette River, Oregon — 1812 Astor Fur Post, 1850 Steamboat Era, 1953-1984 Flood Control, Willamette Falls. For thousands of years the Willamette Valley was the homeland of the Kalapuya, eight independent groups whose territory stretched from the Cascade Range west to the Coast Range and from the Columbia south to the Calapooya Mountains. They burned the prairies each fall to encourage camas, tarweed, acorns, and game, and used the river as a corridor for travel, fishing, and trade. Epidemics reduced them from many thousands to roughly 400 survivors. On January 22, 1855, at Dayton, Superintendent of Indian Affairs Joel Palmer negotiated the Treaty with the Kalapuya — the Willamette Valley Treaty — under which the Kalapuya and neighboring Clackamas and Molala bands ceded nearly the entire valley; the Senate ratified it on March 3, 1855, and the tribes were removed to the Grand Ronde Reservation. Their descendants belong chiefly to the Confederated Tribes of Grand Ronde and the Confederated Tribes of Siletz.

Euro-American settlement arrived with the fur trade: in 1812 the Astor Fur Post became the first such settlement in the region. Logging began in the 1830s, as newly arrived settlers turned the valley's fir and cedar into lumber. Ewing Young raised a sawmill near Newberg in 1838, and by 1841 a mill was operating at Willamette Falls in Oregon City, using the river as both power source and highway. By 1850 dozens of mills lined the valley, together cutting some 41 million board feet a year and supplying an export trade to the Sandwich Islands. Steam power arrived in the 1850s, and in the 1870s lower-Willamette mill owners replaced circular saws with more efficient band saws. Log drives, splash dams, and river rafts fed a timber industry that ran through the 1920s.

The steamboat era opened in 1850, when the Lot Whitcomb made its first trip up the Willamette. A century later, between 1953 and 1984, the U.S. Army Corps of Engineers built 13 dams across the basin for flood control. At Oregon City, Willamette Falls — the 45-foot horseshoe that had been the Clackamas people's principal fishing site — was sold to the Confederated Tribes of the Grand Ronde in 2019.

Systematic observation began with the National Weather Service, which started recording the river's gage height at Portland in 1879. During the flood of June 7, 1894, with no upstream dams to hold back the water, the Willamette rose to a gage height of about 33 feet at Portland. Discharge measurement came later: the USGS did not begin gauging streamflow at Portland until 1972, and today five USGS gauges track the river's flow at Harrisburg, Corvallis, Albany, Salem, and Portland. At the lowermost station, near the Morrison Bridge, the river averaged about 33,220 cubic feet per second between 1972 and 2013.

The river's modern chapter has centered on cleaning up more than a century of industry. In December 2000 the EPA added Portland Harbor — a ten-mile reach between the Broadway Bridge and the southern tip of Sauvie Island — to the Superfund National Priorities List, its sediments laden with PCBs, polycyclic aromatic hydrocarbons, dioxins, pesticides, and heavy metals. NOAA and fellow trustees launched a Natural Resource Damage Assessment in 2010, and the EPA issued its binding Record of Decision on January 6, 2017. Oregon's Department of Environmental Quality has pursued a basin-wide Total Maximum Daily Load program targeting temperature, bacteria, and mercury. Today the Willamette carries a Class II rating and is a designated water trail — the Willamette River Water Trail, stewarded by Willamette Riverkeeper — supporting the Portland and Salem economies.