From Apr 14th 2016, Zidong railway began upgrading with total investment of 1.1 Billion RMB, and the scheduled completion date is the end of 2017. After this upgrade, the rail speed limit of Zidong railway will upgrade from less than 50 km/h to 120 km/h.[2] Dongying will be fully connected with Qingdao–Jinan railway within 1 hour, and travel time between Dongying and Jinan will be shortened from 3.5h to 2h.
The electrified railway reopened on 30 September 2018.[3]
^"【信息速递】淄东铁路扩能改造工程顺利开通,向国庆69周年献礼!" [Information Express: The East China Railway expansion project was successfully opened to pay tribute to the 69th anniversary of the National Day!] (in Chinese). 3 October 2018. Retrieved 14 January 2021.