1. On November 18, 1926, a major flood struck the city of Portland, causing significant damage to buildings and infrastructure. The flood was caused by heavy rain and melting snow, and resulted in over 10 deaths and widespread displacement.

2. November 18, 1978 marked the first day of construction on the Oregon Convention Center in Portland. The facility was designed to host large events and conventions, and has since become a hub for business and culture in the city.

3. On November 18, 1982, Bend-based company G5 Aviation successfully completed the first test flight of its new airship. The airship was designed to serve as a low-cost alternative to traditional aircraft, with applications in transportation and cargo delivery.

4. The Oregon Zoo celebrated the birth of a female Asian elephant named Rose-Tu on November 18, 1994. Rose-Tu went on to become a beloved resident of the zoo and gave birth to several offspring of her own.

5. On November 18, 2014, the Portland City Council voted unanimously to approve a plan to address the city's growing problem of homelessness. The plan included measures to increase affordable housing, provide services to homeless individuals, and improve communication and coordination between government agencies and non-profit organizations.