Hillsboro ( ) is a city in the U.S. state of Oregon and the county seat of Washington County. Situated in the Tualatin Valley on the west side of the Portland metropolitan area, the city hosts many high-technology companies, such as Intel, in an area locally known as the Silicon Forest. The population was 106,447 at the 2020 census, making Hillsboro the fifth-most populous city in Oregon.
Settlers founded a community here in 1842, later named after David Hill, an Oregon politician. Transportation by riverboat on the Tualatin River was part of Hillsboro's settler economy. A railroad reached the area in the early 1870s and an interurban electric railway about four decades later. These railways, as well as highways, aided the slow growth of the city to about 2,000 people by 1910 and about 5,000 by 1950, before the arrival of high-tech companies in the 1980s.
Hillsboro has a council-manager government consisting of a city manager and a city council headed by a mayor. In addition to the high-tech industry, other sectors important to Hillsboro's economy are health care, retail sales, and agriculture, including grapes and wineries. The city operates more than twenty parks and the mixed-use Hillsboro Stadium, and ten sites in the city are listed on the National Register of Historic Places (NRHP). Modes of transportation include private vehicles, public buses and light rail, and aircraft at the Hillsboro Airport. The city is home to Pacific University's Health Professions Campus.
History
The European-American community was founded by David Hill, Isaiah Kelsey, and Richard Williams, who arrived in the Tualatin Valley in 1841, followed by six more pioneers in 1842. The locality went by two other names—East Tualatin Plains and Columbia—before it was named "Hillsborough" in February 1850 in honor of Hill, when he sold part of his land claim to the county. On February 5, 1850, commissioners chosen by the territorial legislature selected the community to be the seat of the county government. The town's name was later simplified to Hillsboro. A log cabin was built in 1853 to serve as the community's first school, which opened in October 1854. Riverboats provided transportation to Hillsboro as early as 1867 when the side-wheel steamer Yamhill worked on the Tualatin River. The first mayor was A. Luelling, who took office on December 8, 1876, and served a one-year term. Notable later mayors included Congressman Thomas H. Tongue (1882 and 1886) and state senator William D. Hare (1885).
On September 30, 1908, 5,000 people gathered as the Oregon Electric Railway opened a connection between the city and Portland with an interurban electric rail line, the first to reach the community. In January 1914, the Southern Pacific Railroad introduced its own interurban service, known as the Red Electric, on a separate line and serving different communities between Hillsboro and Portland. SP discontinued its Hillsboro service on July 28, 1929, In 1891, the courthouse was remodeled and a clock tower was added, and the building was expanded with an annex in 1912. A new courthouse replaced the brick structure in 1928. The last major remodel of the 1928 structure occurred in 1972, when the Justice Services Building was built and incorporated into the existing building. A drinking water and electricity distribution system added in 1892–93 gave the town three fire hydrants and minimal street lighting. Hillsboro built its first sewer system in 1911, but sewage treatment was not added until 1936. In 1913, the city built its own water system, and the first library, Carnegie City Library, opened in December 1914. From 1921 to 1952, the world's second-tallest radio tower stood on the south side of the city, but in 1952, the wireless telegraph tower was demolished. During the 1950s and 1960s, the privately owned company Tualatin Valley Buses, Inc., provided transit service connecting Hillsboro with Beaverton and Portland. It was taken over by the publicly owned transit agency TriMet in 1970.
In 1972, the Hillsboro City Council passed a Green River ordinance banning door-to-door solicitation, but it was ruled unconstitutional by the Oregon Supreme Court in a 1988 decision. The court determined that the city ordinance was overly broad, in a case that was seen as a test case for many similar laws in the state. The Aloha campus was followed by the Hawthorn Farms, then Jones Farm campus adjacent to the airport in 1982, and finally by the Ronler Acres campus in 1994. U.S. President Barack Obama visited the city and Intel's Ronler Acres campus in February 2011.
Geography
The United States Census Bureau reports the city has a total area of , all of which is land. In 2013, Hillsboro itself reported an area of , equivalent to . The city is located in the Tualatin Valley, and the Tualatin River forms part of the southern city limits. The city's terrain is fairly level, consistent with an agricultural past and the farms still in operation. Hillsboro is about west of Portland and immediately west of Beaverton, at an elevation of above sea level. Most parts of Washington County use a numbering system and cardinal direction orientation based on a grid that begins horizontally at the Willamette River in downtown Portland, and Vertically at the Willamette Baseline. In January 2015, the city began the process of making all addresses and streets within Hillsboro conform to the internal grid, through the Connecting Hillsboro Address Project.
The internal grid in Hillsboro centers on the downtown intersection of Main Street, which runs east–west, and First Avenue, which runs north–south. Most addresses within the city include a quadrant prefix: NW, NE, SW, or SE. Main Street is simply designated as East Main or West Main, and First Avenue is only North First or South First. Addresses on the streets' south side and the avenues' east side have even numbers, while odd numbers are on the opposite side. All cul-de-sacs are named courts. Blocks in the downtown core are long on each side.
- Orenco consists of the Orenco Townsite Conservation zone (encompassing a former company town originally created by the Oregon Nursery Company) and the Orenco Station sub-area, which is described in the city code as a "compact, transit-supportive mixed-use neighborhood with reduced automobile reliance".
- The Hawthorn Farm / Fair Complex Plan District is centered on the Hawthorn Farm LRT station and the Washington County Fairgrounds (known since 2019 as the Westside Commons).
- Amberglen, located just south of the Tanasbourne neighborhood, is envisioned as "a vibrant, regional activity center enlivened with high-quality pedestrian and environmental amenities, taking advantage of the region’s light rail system". Located within the district is Oregon Health & Science University's West Campus.
- The South Hillsboro planning district encompasses the newly annexed South Hillsboro neighborhood, described in the city code as "a complete, connected and green community". The neighborhood, built on land once used as a hobby farm by William Ladd and Simeon Reed, is slated to become "a residential mixed-use community organized around a town center and complemented by a village center". lies within Hillsboro's Industrial District, where many of the Silicon Forest's manufacturing and technology businesses reside. Over half of the city's total employment is located within the Hillsboro Industrial District.
- The city's Comprehensive Plan outlines several other plan areas not defined in the city code: Quatama, Tanasbourne, NE 28th Ave/East Main Street Plan Area, and Witch Hazel Village.
Climate
Summers in Hillsboro are generally warm, but temperatures year-round are moderated by a marine influence from the Pacific Ocean. The Willamette Valley in which Hillsboro lies receives the majority of its precipitation during the winter months, with the wettest period from November through March. Hillsboro receives precipitation on 161 days per year, on average. The average yearly precipitation between 1930 and 1998 was . August is the warmest month with an average high temperature of , while January is the coolest month with an average high of . The highest recorded temperature, , occurred on June 28, 2021, and the lowest, , occurred in January 1930.
|source 2 = Weather Atlas (UV and humidity)