Basin Electric needed electrical system upgrades at the Laramie River Station (LRS) because of the aging, existing system. As the original plant design engineer back in the late 1970s and early 1980s, we used our extensive knowledge of the station to upgrade the 6.9-kV medium voltage switchgear with new ABB arc-resistant switchgear beginning in early 2000 and completed the final medium voltage switchgear replacement in 2010. Along the way, careful planning was required to complete the upgrades within regularly scheduled outages. The common system switchgear upgrade presented unique challenges because two of the generating units provide power to the western grid and the third provides power to the eastern grid. Our team uniquely designed the control and protection systems to prevent connection of the two grids.