Mark Twain Transmission Project

Stated Purpose:

The Mark Twain transmission project is a line consisting of two segments that will run from Palmyra, MO to the Iowa border. The 100 mile line is one of the MISO multi-value projects (MVP) approved in 2011, which will help reduce congestion and improve reliability for the transmission grid, and provide better access to new renewable energy sources.

Line Capacity:

345 kV

Route Description:

One segment of the line will run from Palmyra to Kirksville, with the other segment traveling from Kirksville to the Iowa border. The project will total about 100 miles of new transmission lines, and a new substation near Kirksville.

Development Timeline:

Starting in 2014, Ameren held open house meetings with communities to inform the public about the project and received regulatory approval in 2018. December 2019 is the in-service date for the project.

Regulatory Process:

After engaging the public on the project, Ameren will likely submit two potential routes to the Missouri Public Service Commission (PSC) for approval. The PSC gave the project conditional approval in April 2016 dependent upon gaining the assent of five counties. In March 2017, a Missouri appellate court issued a decision that overturned this conditional approval, stating that Ameren should have had this authorization before receiving state regulatory approval. Ameren gained final approval for the project in January 2018.



Community Feedback:

Ameren will hold open house meetings to provide an opportunity for communities and landowners to learn about the project and offer insight into potential routes. The open house meetings will occur in August of 2014. Several families wish to intervene in an ongoing lawsuit between Ameren and the PSC about the ability of Ameren to use eminent domain without oversight from the PSC.

Commissioners for Adair County in Missouri passed a resolution in October 2014 opposing the project. They cited the fact that the transmission line would not bring power to the county, and that they had other concerns relating to property and health claims. Several other landowners and community members have voiced opposition to the project for the same reasons. After a hearing in 2015, commissioners sent a letter to the Missouri PSC opposing the project.

One of the routing options for the project could also impact an Amish community near Greentop. There are also concerns relating to one of the potential routes running through a Mennonite community near Kirksville.

In mid-2017, Ameren held another round of open house meetings to consider new routing options for the project. Ameren is currently working with counties that project would pass through to gain their assent for use of local roads.

Clean Energy Potential:

Ameren notes that the project will increase access to new renewable energy generation in the region.

News Archive

Construction begins on Mark Twain Transmission Project May 23, 2018

ATXI gearing up for Mark Twain Transmission Project construction May 4, 2018

Ameren updates Adair Co. Commission on Mark Twain project March 20, 2018

Ameren Transmission drops lawsuits over original route for NEMO transmission line January 25, 2018

ATXI outlines next steps for Mark Twain line January 17, 2018

Missouri Regulators OK Transmission Line 'Needed To Integrate Wind Energy' January 11, 2018

Missouri PSC approves Mark Twain Transmission Line January 10, 2018

State approves Ameren transmission line for northeast Missouri January 10, 2018

The next steps for ATXI, Mark Twain line September 11, 2017

Ameren unit picks route for 100-mile Mark Twain transmission project September 7, 2017

ATXI ready to move forward after vote September 6, 2017

New route for Ameren's northeast Missouri transmission line gains local approval September 6, 2017

Ameren Picks Final Route for Mark Twain Transmission Line September 6, 2017

Adair County Commission votes, 2-1, to approve Mark Twain line September 5, 2017

Schuyler County Commission Grants Assent to Mark Twain Transmission Project September 5, 2017

Knox County Commission Grants Assent to Mark Twain Transmission Project August 18, 2017

Marion and Lewis County approve Mark Twain Transmission Project August 14, 2017

Marion County Commission approves of revised Mark Twain Transmission Project August 14, 2017

Adair County Commission, ATXI to hold public hearing August 8, 2017

ATXI drops lawsuit against Adair County August 1, 2017

Marion County may soon rescind disapproval of power project July 27, 2017

Missouri Supreme Court will not hear Ameren appeal over power line June 27, 2017

City Council asked to reconsider support for new ATXI route proposal June 19, 2017

ATXI makes its case - again - to Adair County June 16, 2017

Public input sought on new route for Mark Twain Transmission Project June 9, 2017

Neighbors United won't be part of suit by Ameren over Mark Twain Transmission Project May 12, 2017

Neighbors United, Rep. Walker still concerned about Mark Twain line May 2, 2017

Ameren: New route proposed for Mark Twain Transmission Project May 2, 2017

Report: Ameren to change route of Mark Twain Transmission Project April 28, 2017

Future of power line project still up in the air April 16, 2017

Ameren asks to send Mark Twain Transmission case to Supreme Court April 14, 2017

ATXI seeking rehearing or transfer to Missouri Supreme Court April 14, 2017

Neighbors United cheers court ruling against transmission line March 31, 2017

Court of Appeals Rules in Favor of Neighbors United, Ameren Weighing Options March 28, 2017

Court rules against Ameren, kills Mark Twain Transmission Project March 28, 2017

Mo. courts, not regulators, may decide fate of 2 big projects November 9, 2016

Adams County receives payment from Ameren November 7, 2016

ATXI files suit against five county commissions in Northeast Missouri November 3, 2016

Adair County vote a win for Neighbors United September 22, 2016

Adair County Commission again votes against Mark Twain Transmission Line September 20, 2016

Marion County Commission votes 2-0 not to endorse Ameren electrical project September 19, 2016

PSC approves Mark Twain line, county remains in opposition April 28, 2016

Ameren to build 95-mile transmission line through 5 northeast counties April 27, 2016

PSC rules on Mark Twain Transmission Project April 27, 2016

PSC gives conditional approval to Mark Twain transmission project April 27, 2016

Ameren optimistic ahead of ruling on Mark Twain Transmission Line April 26, 2016

Missouri PSC ruling on proposed Mark Twain Transmission Line expected soon April 25, 2016

Fate of transmission line in PSC's hands, despite local opposition April 12, 2016

Wind Power Wiggles Through Midwest Transmission Roadblocks April 11, 2016

PSC sees Ameren, Grain Belt transmission lines differently April 7, 2016

Locals worried about Ameren power project through Marion County March 24, 2016

Group speaks out against transmission line project March 21, 2016

Mark Twain Transmission Project creates sparks in Jefferson City January 25, 2016

Public Service Commission delays ATXI hearings to January December 3, 2015

PSC modifies hearing schedule in ATXI transmission line case December 2, 2015

Opponents of transmission line say 'right to farm' amendment precludes project November 15, 2015

PSC hearing held at Truman State October 28, 2015

Neighbors United voices concerns about new Ameren transmission line October 23, 2015

PSC announces public hearings in Ameren transmission line application September 29, 2015

PSC ruling gives hope to Mark Twain Transmission Line opponents July 2, 2015

Mark Twain Transmission Project opposition continues in Knox County June 19, 2015

Adair County Commissioners oppose Mark Twain Transmission Project June 17, 2015

Deadline set to intervene in controversial Mark Twain power project June 6, 2015

Missouri Public Service Commission sets intervention deadline for Ameren's Mark Twain Transmission Line June 4, 2015

PSC gives Ameren the nod to build 7 miles of power line in Marion County June 4, 2015

Mark Twain Transmission Project tax revenue rate changes May 26, 2015

Battle continues between Neighbors United and Ameren Transmission Company May 12, 2015

Adair Co. Commissioners say no word on tax revenue from transmission project March 30, 2015

Ameren seeks ruling on PSC from apellate court March 26, 2015

Ameren's NE Missouri project could impact state's say in high-voltage lines March 8, 2015

Mark Twain Transmission Project to bring tax revenue to Adair County March 5, 2015

Ameren, Neighbors United clash at final Mark Twain open house February 26, 2015

Community to Discuss Transmission Line February 25, 2015

Neighbors United members continue fight against Ameren February 17, 2015

Ameren officials share Mark Twain Transmission line plans February 11, 2015

Ameren finalizes route but court, PSC decisions loom February 11, 2015

Ameren Transmission announces final route for Mark Twain Transmission Project February 10, 2015

Ameren Selects Southern Route for Mark Twain Transmission Line February 10, 2015

Mark Twain Transmission line location reportedly set February 9, 2015

Marion County Commission votes "no" to Mark Twain Transmission Line November 25, 2014

Shekinah Mennonite community to see impact from Ameren November 19, 2014

Kirksville City Council drafts letter opposing Ameren Transmission Project November 18, 2014

Amish community to see impact from Ameren Transmission Project November 6, 2014

Ameren project concerns Council November 4, 2014

Protesters, questions at Mark Twain Transmission Project open house October 31, 2014

Ameren officials hold open house October 30, 2014

Ameren meets with city, county officials before open house October 30, 2014

Ameren : brings Mark Twain Transmission Project open house to Palmyra October 29, 2014

Ameren gets input on Mark Twain Transmission Line at first of three open houses October 28, 2014

Three open houses about Mark Twain Transmission Line set for this week October 27, 2014

Knox County Commissioners join opposition of Ameren project October 23, 2014

Families fighting Ameren transmission project score court victory October 21, 2014

Judge says he plans to rule against Ameren in legal fight over northern Missouri power lines October 20, 2014

Adair County Commission drafts resolution opposing power line October 15, 2014

Adair County Commissioners oppose Ameren project October 15, 2014

Ameren to hold Mark Twain open houses in late October October 13, 2014

Landowners speak out regarding Ameren power lines October 10, 2014

Lawsuit filed between Ameren Transmission Company of Illinois and Missouri Public Service Commission October 9, 2014

Missouri families file suit against power line project October 9, 2014

Missouri Property Owners Seek to Intervene in Ameren Lawsuit Against the Public Service Commission Concerning Eminent Domain and the Mark Twain Transmission Project October 8, 2014

Citizens express opposition to Ameren transmission line project September 10, 2014

Final route for Ameren's Mark Twain project expected by end of year August 18, 2014

118 attend transmission line project open house in Palmyra August 13, 2014

Mark Twain Transmission Project Is Coming Through Knox County August 11, 2014

Marion County residents get chance to weigh in on Ameren Transmission Company project August 7, 2014

Residents weigh in on multi-million dollar transmission line project August 6, 2014

Ameren gets input on transmission line August 5, 2014

Northeast Missouri residents discuss Mark Twain Transmission Project August 5, 2014

Meetings set for Mark Twain Transmission Project July 26, 2014

Your Thoughts:

We all know that clean energy transmission is vitally important to our energy future. It brings economic opportunity to rural areas, enables wind development and improves the reliability of your grid. But to build it properly - to create projects that work best for you and your community - requires your knowledge and participation. That's why we've created this database.

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