In 1824 the British Hudson's Bay Company established a fur trade post at Fort Vancouver on the north side of the Columbia, making use of the rich resources and navigable waterways of the Slough. With increasing numbers of American white settlers laying claim to northwest lands, in 1846 the British agreed to a boundary. Lands south of the 49th parallel would belong to the U.S. Native groups waged little resistance since most had been wiped out by disease spread by settlers nearly twenty years earlier. Although individual Indians remained in the Portland area, by 1855 a majority were forced to cede their lands and move to the Grand Ronde Reservation.

Left. The British Hudson's Bay Company sited Fort Vancouver at what became Vancouver, Washington on the Columbia floodplain for navigational and trade purposes. In 1849, the U.S. Army established Vancouver Barracks, laying claim to the region for the U.S. Notice Vancouver's Officers Row, circa 1855, on the hillside. Courtesy of the National Park Service

   At the turn of the century, over 82,000 people lived in Portland. By 1915, the city grew to 232,500 people. Communities such as St. Johns rose in the area known as "The Peninsula" between the Columbia, the Willamette, and the Slough. In 1909, the Swift Meat Packing Company established Kenton in what is now north Portland. The people of these communities used the waters of the Slough and the Willamette, first for navigation and subsistence, and later for sewage and industrial disposal.