Stockton passengers to use the ACE trip which terminated at Lathrop/Manteca. The trip was extended to Stockton on August 1, 2005. At that time, service to Santa Clara was suspended to allow for the construction of a second platform and pedestrian tunnel at the station. On August 28, 2006, ACE added a fourth round trip, which operated midday using one of the existing trainsets. On November 7, 2006, San Joaquin County voters approved a 20-year extension of Measure K. Suffering from reducing funding due to the Great Recession, ACE cut the lightly used midday trip on November 2, 2009. On May 14, 2012, ACE restored service to Santa Clara station. On October 1, 2012, a fourth rush-hour round trip was added, running approximately one hour after existing trips. Altamont Corridor Express In December 2012, the service was rebranded from Altamont Commuter Express to Altamont Corridor Express to reflect plans for a broader scope of service. In March 2014, ACE opened a $65 million, maintenance facility in Stockton. On July 1, 2015, management and governance of the San Joaquin passed from Caltrans to the new San Joaquin Joint Powers Authority. The SJJPA has nominal control over the SJRRC, but delegates all responsibility over ACE to the SJRRC. On March 7, 2016, an ACE train was derailed by a mudslide in Niles Canyon near Sunol. The front car plunged into the rain-swollen Alameda Creek. Fourteen passengers were injured, but there were no fatalities. ACE received Road Repair and Accountability Act funds in order to initiate Saturday service in January 2018, with two Saturday round trips added in September 2019. Future plans In association with the California High-Speed Rail project, the ACE line is planned to be dramatically upgraded and expanded. Beginning around 2008, initial plans called for the Altamont Corridor Rail Project to produce a high speed rail "Super ACE" capable of halving the travel time between the endpoints. As the high-speed rail project was scaled back and rerouted to Pacheco Pass several years later, these plans were replaced with the more modest ACEforward program. The San Joaquin Regional Rail Commission issued a notice of intent to proceed with an Environmental Impact Statement in June 2013; this was released in 2017 and prioritized goals as either long term or short term. Short term goals included track improvements, a possible reroute through downtown Tracy including new stations, a West Tracy station, and a