ITC Midwest Begins Construction on Morgan Valley-Twinkle Project
February 18, 2026 | Midwest
Following regulatory approval by the Iowa Utilities Commission, ITC Midwest has started construction on the Morgan Valley-Twinkle project. This 61-mile, 345 kV line will connect the Morgan Valley Substation southwest of Cedar Rapids to the new Twinkle Substation under construction in Marshalltown. This is the first of five MISO Long-Range Transmission Planning (LRTP) Tranche 1 projects ITC Midwest will build, totaling approximately 200 miles of new 345 kV lines.
Scheduled to be placed in service by September 2027, the Morgan Valley-Twinkle line will provide numerous benefits and deliver value for electric consumers locally and regionally. When completed, this project will:
- Increase transmission infrastructure to improve system reliability
- Enhance grid resilience to better withstand extreme weather
- Expand access to generation resources by reducing transmission system congestion
- Improve distribution of lower-cost energy resources, including renewables
The public information meetings for the Morgan Valley-Twinkle project were held across a four-county area in May 2023, kicking off easement acquisition efforts. These efforts resulted in ITC Midwest securing a 99.6% voluntary easement rate. The 345 kV line will be double-circuited on new structures with an existing 161 kV line along approximately the western half of the project. Most of the new line will be built on existing right-of-way, with about 3.5 miles located in greenfield areas.
Work began in December to remove segments of a decommissioned 115 kV line, followed in early February by removal of the existing 161 kV line that will be replaced along the route. Vegetation management and matting installation also began late last year. As route staking and mat installation continues, the first foundations have now been poured, and steel structures and other project materials are being delivered to the construction area.
To meet the project schedule, construction is starting in the middle of the line route with crews working simultaneously in both directions.
Learn more about the Morgan Valley-Twinkle project.
Additional nearby projects will increase system capacity while supporting future energy demand. These include construction of ITC Midwest’s new Big Cedar Substation, which remains on track to be energized in March. Construction was recently completed to double-circuit the existing Morgan Valley-Beverly 345 kV line near the new substation site. By designing the line to accommodate a second circuit when it was placed in service in 2020, ITC Midwest was able to reduce costs while supporting system reliability and future load growth.
