Project
Limestone Ridge Reliability Project
We were the engineer-procure-construct (EPC) contractor for the Limestone Ridge project, which increased electric reliability in southeast Missouri through new and rebuilt transmission lines, two new substations and one substation update.
This complex initiative was completed safely, on schedule and within budget, allowing Wabash Valley Power Alliance to strengthen its ability to provide reliable power to residents and industrial customers in the region.
Collaboration was essential throughout the project, across multiple projects, client teams, regulatory agencies and large industrial customers. Individual components within this project included:
- Wittenberg Substation: a greenfield, 138-kV four-breaker ring bus facility
- Trail of Tears Substation: a greenfield, 161-kV three-bay breaker-and-a-half substation
- Charmin Bulk Substation: brownfield upgrades to a 161-kV facility
- Transmission line T21: a 1-mile 69-kV relocation with distribution underbuild
- Industrial customer to Trail of Tears transmission lines: two 1-mile, 161-kV lines
- Transmission line T23: 2 miles of 69-kV relocation
- Grand Tower-to-Wittenberg transmission line: 2 miles of 138-kV rebuild with Mississippi River crossing
Client
Wabash Valley Power Alliance
Location
Wittenberg, Missouri
Region
Midwest
Services
Electrical Transmission & Distribution
Industry
The Grand Tower-to-Wittenberg transmission line reconstruction required close coordination with the U.S. Coast Guard to safely pull the line for the half-mile Mississippi River crossing. The Coast Guard oversees helicopter use over the river, and we coordinated with traffic on the river during a 12-day construction period. Close coordination with the Coast Guard was required for safety during helicopter operations. The project was completed without any safety incidents.
Large industrial customers within the service area created challenges for outage periods. By providing an alternate power source, we were able to decrease the required industrial outage time to just five days.
Our environmental specialists completed environmental surveys and biological assessments to obtain federal, state and local permits for transmission line routes and substations. Compliance with the Clean Water Act (CWA) Section 404/Section 10, CWA Section 401, CWA Section 402, Section 7 and Section 106 was required along with compliance with the Migratory Bird Treaty Act and Bald and Golden Eagle Protection Act. Credit purchase from a bat mitigation bank, a large dissipater and a 300-foot culvert along a section of streambank were among the solutions implemented.
Project Challenges
Extensive civil work in a remote region to level the site for Wittenberg Substation and an access road
Supply chain issues addressed before construction start
Coordination of outages for large industrial customers
Atypical use of concrete poles for new transmission lines installed within a flood plain, where bases would be underwater after installation
Half-mile span for crossing of Mississippi River
Movement of energized lines to maintain power to two customers
Environmental mitigation for bats
Installation of a 300-foot-long culvert along an existing stream
