Mark Twain Transmission Project

The Mark Twain Transmission Project is classified as a multi-value project (MVP) in the MISO 2011 expansion plan. The project will create a 345-kV path through central and eastern Missouri, beginning at the Iowa state line, continuing to the Zachary substation near West Adair, and continuing to the Maywood substation near Palmyra.

Project Sponsor Line Miles Voltage (kV) From State To State Year in Service
Ameren Transmission Company 96 345 IA MO 2020
Estimated Costs ($M) Voltage Type Project Status Project Group Origin Point Destination Point
250 Single Operating GRP Iowa/Missouri State Line Maywood
Interstate Build Start NERC ISO/RTO Country Project Partners