| Library Name: | Mid-Columbia Libraries |
| Type: | Public library |
| Established: | 1948 |
| Location: | Tri-Cities metropolitan area, Eastern Washington, U.S. |
| Coordinates: | 46.2036°N -119.1592°W |
| Annual Circulation: | 2.3 million |
| Pop Served: | 250,500 |
| References: | Washington Public Library Statistical Report, 2018[1] |
Mid-Columbia Libraries is a library system in Eastern Washington. There were 250,500 people in its service area in 2018,[1] which spans the Tri-Cities metropolitan area except for Richland, which retains a city library: West Richland, Kennewick, and Pasco, and surrounding Benton, Franklin, and parts of Adams Counties are part of Mid-Columbia. It was founded in 1948, originally to serve patrons in unincorporated parts of the counties.[2], the last city to be annexed was Kennewick, and several cities which were still independent on paper, including Pasco and West Richland, paid Mid-Columbia to gain patronage rights for city residents.[3] The system considered expanding to cover Walla Walla County Rural Library District in 2012.[4]