Elegant Infill. The land initially developed in the 1920's once housed a PG&E substation that was designed by PG&E architect Ivan C. Frickstad. The substation was a cement-plastered, Mission-style structure was built alongside the historic Oakland Avenue bridge. The substation was closed in 1991 and sat vacant until 2014 when Piedmont Station, LLC brought this project to life. HHJA is executive architect on this project.