STLPL About - Hero
About Spire STL Pipeline
A look back at the project history


With the STL Pipeline, we've created more diversity in our energy supply

This means more reliability for our distribution customers and lower rates for customers in the St. Louis market.

The pipeline helps us meet the region's growing energy and economic development needs to better serve customers, while encouraging new commercial and industrial growth opportunities in the region.

And, it also eliminates the need for back-up propane systems, resulting in lower emissions and reduced maintenance costs.

Doing what's best for customers is doing what's best for the environment

Protecting the environment is important to us. Like you, we want to preserve sensitive areas and endangered species. From planning through construction, and with regular maintenance now that the pipeline is in use, we will do everything we can to protect the environment.

We partnered with an environmental firm to carefully study the route and identify any ecological and archeological concerns. The pipeline route was adjusted to ensure requirements were met to protect the environment.

During construction, we used modern and less disruptive methods, such as horizontal directional drilling to avoid disturbing sensitive areas and minimize environmental impacts. 

As an interstate project, the Spire STL Pipeline has been reviewed for siting and permitting by the Federal Energy Regulatory Commission (FERC). The FERC was the lead agency for other federal and state, and local permitting authorities. The pipeline is wholly owned and operated by Spire STL Pipeline LLC.

Here’s a look back at our project schedule:

Date Event
July 2016 Pre-filing process begins
October 2016 File draft resource reports
November 2016 FERC scoping sessions
August 2018 Received FERC 7C certificate
November 2018 FERC notice to proceed  
January 2019 Construction start
November 2019 Pipeline in service

Mapping it out

The 65-mile steel pipeline* interconnects with existing Rockies Express Pipeline in Scott County, Illinois. From there, the pipeline will travel through Greene and Jersey Counties in Illinois and St. Charles and St. Louis Counties in Missouri before connecting with existing Spire facilities. From there, the pipeline travels through the north portion of St. Louis County for six miles before terminating at the Enable Mississippi River Transmission Line.

Spire conducted civil, environmental and cultural resource surveys along the path to identify the best possible route with the greatest protection to sensitive areas. 

*The 65-mile pipeline includes 59 miles of new build underground pipe in Illinois and six miles of underground pipe in Missouri, referred to as the North County Extension.

Spire STL Pipeline map

Construction doesn’t end until the landscape is restored

Weather permitting, restoration efforts begin as soon as possible after construction work is complete to restore the land. We use a two-phased approach. First is “preliminary grading” to backfill the trench. Next is a "final grading" process to smooth out and clean up the area, planting grass seed and other native vegetation, and restoring any necessary drain systems. Restoration measures are monitored and maintained until the area is similar in nature to its original condition.

Pipeline construction sequence: Land surveying, clearing, grading, trenching, pipeline stringing, bending pipe, welding, x-ray and repairs where necessary, coating where necessary, lowering the pipe, installing valves and fittings, back-fill, testing, clean-up and restoration. Download this image here.

1“North American Midstream Infrastructure Through 2025: Leaning into the Headwinds” April 201

The Federal Energy Regulatory Commission (FERC) was the lead federal agency in charge of overseeing the permitting process for interstate natural gas transmission pipelines.

To guide its decision making process, FERC conducted a comprehensive environmental review of the project, in accordance with the National Environmental Policy Act (NEPA). Throughout this process, FERC worked closely with other federal, state and local agencies. Landowners and the general public also had numerous opportunities to participate in the process by attending public meetings and providing public comments to FERC.

Before the formal environmental review of the project began, Spire STL Pipeline spent more than a half year engaging with and gathering input from stakeholders in what is known as the FERC pre-filing process. Once the pre-filing process was completed, Spire STL Pipeline filed an application for a Certificate of Public Convenience and Necessity with FERC, which initiated the formal environmental review of the project. The application described the purpose and commercial need for the project, the transportation rate to be charged to customers, proposed project facilities, and how the company will comply with all applicable regulatory requirements. Spire STL Pipeline evaluated project alternatives, identified a preferred route, and completed a thorough environmental analysis.

FERC then reviewed the application in order to evaluate the need and overall impact of project construction and operation, and will summarize its findings in an environmental review document. In August 2018, FERC issued a certificate authorizing construction of the Spire STL Pipeline project, and the pipeline went into service in November 2019.