Happy Valley, Oregon is a census-designated place and unincorporated community in Washington County, Oregon, United States. By road it is 10.9 miles (17.5 km) west of downtown Portland. As of the 2010 Census, the population was 49,425. On January 9, 1912, the community received its name with the opening of a post office named Aloha; the area had previously been known as Wheeler Crossing. According to Oregon Geographic Names, the origin of the name Aloha is disputed.