Richland is a city in Benton County in the southeastern part of the U.S. state of Washington, at the confluence of the Yakima and the Columbia Rivers. As of the 2010 census, the city population was 48,058. April 1, 2011 estimates from the Washington State Office of Financial Management put the city's population at 49,090. Along with the nearby cities of Pasco and Kennewick, Richland is one of the Tri-Cities of Washington, home to the Hanford nuclear site.
For centuries, the village of Chemna stood at the mouth of the current Yakima River. Today that village site is called Columbia Point. From this village the Wanapum, Yakama and Walla Walla Indians harvested the salmon runs entering the Yakima River. Captain William Clark of the Lewis and Clark Expedition visited the mouth of the Yakima River on October 17, 1805.
In 1904-1905, W.R. Amon and his son Howard purchased 2,300 acres (9 km2) and proposed a town site on the north bank of the Yakima River. Postal authorities approved the designation of this town site as Richland in 1905, naming it for Nelson Rich, a state legislator and land developer. In 1906, the town was registered at the Benton County Courthouse. It was incorporated on April 28, 1910 as a Washington Fourth Class City.