The Mark Twain Transmission Project is a new, 345,000-volt (345kV) approximately 96-mile transmission line to be built in northeast Missouri. It includes construction of a new substation near Kirksville, Missouri. Ameren Transmission Company of Illinois (ATXI) received approval from the Missouri Public Service Commission (PSC) on January 10, 2018, to proceed with the construction of the Mark Twain Transmission Project.

The line construction for the Mark Twain Transmission Project will be completed in the following phases: 

 

Construction primarily takes place during daylight hours, but some work may be completed after dusk. Additionally, our contractors may travel to and from the job site before dawn or after dusk. Affected landowners, who have signed an easement with ATXI, will be contacted in person, by phone and/or in writing at least 24 hours prior to the beginning of construction on their property.

This project is necessary to promote grid reliability; relieve congestion to the energy grid; meet local energy needs; and promote renewable energy, such as wind power.

The proposed new route will run through Adair, Knox, Lewis, Marion and Schuyler counties and includes construction of the Zachary Substation near Kirksville, Missouri. It will collocate nearly 100 percent of existing right of way on Northeast Power's 161 kV line between Palmyra and Kirksville and Ameren Missouri's 161 kV line from Kirksville to the Iowa border. The new route will minimize impact to landowners, communities and existing farm land, and result in fewer utility structures along the existing right of way. New right of way will be sought in Adair County to connect the Zachary and Adair substations and in Marion County to connect to the Maywood Substation. Additionally, 50 feet of expanded right of way is needed along the Ameren Missouri line in Adair, Marion and Schuyler counties. New right of way will be sought in Adair County to connect to the Zachary and Adair substations - and in Marion County to connect to the Maywood Substation. ATXI is working with landowners to get their feedback on where the new right of way should be.

This project is expected to generate millions of dollars in economic activity and annual tax revenues to support schools, roads, police and emergency and social services in the five Missouri counties where the line will be located (Adair, Knox, Lewis, Marion and Schuyler counties).

Approximately 55 miles of Northeast Power's line, running between Palmyra and Kirksville, will be completely rebuilt, and the current wooden H-frame transmission structures will be replaced by fewer steel monopoles. Due to the age of Northeast Power's current 161kV line, replacement would likely be necessary within 10 to 15 years, which would cost approximately $30 million. Working with ATXI allows Northeast Power to save a significant amount of money while making important infrastructure improvements. In addition, future right of way maintenance costs will be split with ATXI, which results in ongoing savings for Northeast Power and its Member-Distribution Cooperatives. Landowners will benefit from new easement payments as well as less burden on farm and, due to the reduced number of poles and the elimination of guy wires and anchors.

As communities grow and new sources of energy are developed, substations are built to meet the increased energy demand and expand the system's ability to handle more energy. After energy is generated at a power plant, it is sent to substations by way of transmission lines. The substations then lower the voltage level so that the electricity can be transported to area homes and businesses through distribution power lines. 

The new Zachary Substation construction began in May 2018 and is located adjacent to Ameren Missouri's existing Adair Substation in Adair County.  It will increase access to renewable sources of energy such as wind, improve local reliability and promote economic growth in northeast Missouri.

ATXI will completely rebuild Ameren Missouri's line between Kirksville and the Iowa border. This project will help avoid costs that would otherwise have been paid for by Ameren Missouri customers. Landowners will benefit from new easement payments as well as less burden on farmland, due to the reduced number of poles and the elimination of guy wires and anchors.

Northeast Power's involvement with the project will not result in a rate increase for member-distribution cooperatives or their member-owners.

ATXI is still in the process of completing the routing and design. However, it is anticipated the new route may cost slightly more than that of the original design. The in-service date is December 2019.

For questions or concerns about real estate, survey work or construction, please contact Contract Land Staff (CLS) agents at 1.877.830.3440. If you have questions specifically for Northeast Power, please call 573.769.2107.

Single steel monopoles with no guy wires or anchors will be used for the majority of the route. At locations where the line turns a large angle or where a full tension dead end is required, two steel structures will be used, because the loads would be too large for a single pole. See the diagram below.

Landowners will be asked to grant a 150-foot-wide easement to ATXI for the right to use a defined strip of land for the construction, operation and maintenance of the electric transmission line. Contract Land Staff (CLS) agents, on behalf of ATXI, will be working with landowners on the easement acquisition process. CLS agents will meet with landowners to discuss easement rights, compensation, survey work, damage settlements, structures, damage settlements and land restoration. If you would like to contact one of our CLS agents, please call 1-888-340-6640.

ATXI will request access to each property to survey for legal boundary, depth of foundation and environmental sensitivities.

As a part of the Project, engineering staff will design the foundation for each transmission line structure. The field data we collect will help our engineers determine the final design and structure locations, and will help to minimize impacts to cultural and biological resources during construction. The design process requires information about the soil where the structure will be located. Collecting soil information is completed using the following steps by our geotechnical field survey crews:

• Partner with our real estate team to request property access.
• Gather samples from each site by digging a 4-6 inch wide hole into the ground, known as a soil boring. Soil boring areas will be filled back in after the survey.
• Review samples to determine the physical properties and layering of the soil.
• Use soil information to design each foundation and structure dimensions.

After receiving permission from landowners during the real estate process, ATXI's contractors will perform wetland and stream surveys, wildlife surveys and archaeological surveys to assess the area before construction. To survey wetlands and streams, our field staff visits locations that we identified through analysis of maps and aerial imagery as streams or potential wetland areas. The purpose of the surveys is to determine if these features can be classified as a wetland or a stream based on U.S. Army Corps of Engineers guidelines. The crew will collect data on vegetation, hydrology and soil characteristics. Our wildlife survey technicians gather information on-site to provide important data about the species living in the area, helping us plan how to minimize impacts to wildlife species and habitat. Archaeological surveys consist of walking the easement area to look for cultural artifacts on the ground. If artifacts are found, they are collected for further analysis. To access areas where visibility is limited, such as woody or grassy areas, archaeologists may hand-dig a small hole to screen soils for artifacts. All excavated shovel test areas will be filled back in after the survey is completed. If a culturally-significant site is identified, additional testing may be required to determine if it is eligible for the National Register of Historic Places.

If you believe your property is located on the proposed final route selection, please feel free to contact ATXI at 877.830.3440 or by email at marktwaintransmission@ameren.com. A member of Contract Land Staff, a group hired by ATXI for real estate matters, can assist landowners with questions and concerns about their property. If you have questions specifically for Northeast Power, please call 573.769.2107.