West Richland is a 22-square-mile (57 km²) city in Benton County, Washington, United States. The population was 11,811 at the 2010 census. The city is located within the Tri-Cities metropolitan area, which is centered in this area the cities of Richland, Kennewick, and Pasco (the Tri-Cities).

The native people of the region were the Chemnapum Indians (closely connected to the Wanapum tribe), living near the mouth of the Yakima River. Lewis and Clark passed through the area in 1805, and an expedition of the Army Corps of Topographical Engineers headed by Robert E Johnson mapped the Yakima Valley in 1841.

In 1853, a road was authorized by Congress to pass through the Yakima valley, and passed through present-day West Richland – but deal did not really begin until the late 1870s. The first schoolhouse was built in 1896 on the Van Horn Property just south of what is now Van Giesen Street. Benton County was created in 1905, Richland was incorporated in 1906, and the West Richland Place was known as ‘Lower Yakima’.

An irrigation canal from the north side of Horn Rapids Dam was built in 1908 to bring water into Richland.

The Yellowstone Trail, a national highway stretching from Albany, New York, to Seattle, was located through the Yakima Valley in 1917 and 1918. It crossed the Fallon Bridge surrounded by Richland and West Richland and subsequently proceeded directly west to Kiona.