The first light rail line of the SacRT opened March 12, 1987. Initial service commenced between Watt/I-80 and 8th & O stations only for the first six months. It was extended to Butterfield that same year on September 5. Much of the line, when it was first built, was single-tracked, though improvements over the 1990s allowed much of the original system to be double-tracked. The line was built mainly using portions of the
Sacramento Northern Railroad and
Sacramento Valley Railroad right-of-ways, coupled with use of structures of an abandoned freeway project. A limited portion of the route runs on streets, mainly in downtown Sacramento. The line became more popular than anyone anticipated, necessitating further expansions and improvements to the system. SacRT has proposed extending the light rail system south to the town of
Elk Grove in phases. The first phase of the southern extension opened on September 26, 2003, with added from
16th Street to
Meadowview. The extension added seven new stations to the system and runs parallel to a railroad right of way. The light rail system was reconfigured in June 2005 with the South Line connected to the Watt I-80/Downtown Line and designated as the Blue Line. The second phase of the southern extension opened more than a decade later on August 24, 2015, with added from Meadowview to
Consumnes River College. The extension added seven new stations to the system. An additional station,
Morrison Creek, was put on hold to open as an
infill station until the adjacent land was developed. Eventually in 2021, despite the land around the station remaining undeveloped, Morrison Creek opened to the public as a station only accessible via pedestrian and bike paths. Sacramento RT added a large parking structure at Cosumnes River College to attract riders from southern Sacramento County and boost ridership. A third planned phase which would extend the line from its current southern terminus to Elk Grove about 2 miles along Bruceville Road is on hold indefinitely due to a lack of funding. Land use and station accessibility must be improved to qualify the extension for
Federal Transit Administration (FTA) grant funding. Construction on this project was not expected to begin until after 2040. In 2019, the city of Elk Grove prepared a study on improving
e-tran Route 110 with
bus rapid transit (BRT) characteristics. Route 110 mostly follows a similar alignment to the proposed Blue Line extension. In July 2024, the city of Elk Grove began conducting a feasibility study over whether to continue forward with the Blue Line extension or the BRT, considering five different light rail and BRT alternatives to expand transit to the city. In March 2026, the city released a draft implementation plan that recommended extending the light rail line to Kammerer Road. The city council approved the plan in April 2026. An additional infill station on the line called
Dos Rios station is being constructed between the Globe and Alkali Flat/La Valentina stations in the Dos Rios Triangle neighborhood of North Sacramento. The station is planned as part of a new housing development project that is funded by California's
cap and trade system, with an opening date set for September 2026. == Station listing ==