Dubuque Pipeline Replacement and Multiple Station Upgrades

  • Dubuque Pipeline Replacement and Multiple Station Upgrades
  • Dubuque Pipeline Replacement and Multiple Station Upgrades
  • Dubuque Pipeline Replacement and Multiple Station Upgrades
  • Dubuque Pipeline Replacement and Multiple Station Upgrades
  • Dubuque Pipeline Replacement and Multiple Station Upgrades


Client: Southern Company: Nicor Gas / Southern Company Gas

Location: East Dubuque, IL to Elgin, IL


Nicor Gas was engaged in a multi-year program to replace the Dubuque Line natural gas transmission pipeline. Approximately 135 miles of 22-inch vintage pipeline with welded joints and related components were replaced through a series of individual projects. d’Escoto provided various construction inspection services for each phase.
• Phases 1 through 6 – Approximately 60 miles from East Dubuque to Freeport of 22-inch pipeline has been replaced with 30-inch Transmission main. These projects included the following challenges; over ten HDDs, over five 24-inch and 30-inch mainline valves installed; Several Transmission stations were reconstructed or incorporated into this project. Stations 100, 200, 280 and 319 interconnections and upgrades including 30-inch and 22-inch pig barrels. The Galena River HDD was completed over a span of two years.
• Galena River HDD —375 feet: 24-inch pipe installed via open cut; one HDD
• Phase 7 – 18 miles of 22-inch main was replaced by 30-inch main. Includes 2 HDDs, Rock River and Montague Road and incorporated Transmission Stations Bunker Hill Road, Mt. Morris Road, Hoisington Road, and Station 241.

Services Provided

Under multiple contracts throughout this initiative, d’Escoto had inspected the construction, installation, and commissioning activities performed by Nicor’s construction contractor. d’Escoto’s experienced team of qualified inspectors included:
• Chief Inspector – Managed and inspected team, and was responsible for the successful delivery of the project; monitored, reported, and assisted with questions regarding contractor and inspector services; maintained direct contact with Nicor personnel
• Chief Weld Inspector – Managed the crew of certified weld inspectors and took overall responsibility of the weld inspections
• Corrosion Inspector (CP 2 Registration) – Conducted on-site inspection, testing, and documentation of constructed cathodic protection and AC mitigation systems
• Office Manager – Provided back-office support to the chief inspector, and those tasks included finalizing, filing, and loading reports to SharePoint; organizing binder documentation; and managing timecards, field equipment, and project supplies
• Instrumentation/Electrical Inspector (SCADA) – Oversaw the installation of all electrical components, including SCADA components and electrical components at valve sites, and documented installation per the IFC drawings of all electrical and SCADA components
• Horizontal Directional Drill (HDD) Inspector – Oversaw and documented all HDD-related activities and reports on conformance to the design specifications.
• Weld Inspectors (AWS Certified) – Visually inspected each weld joint to verify that a sound weld was produced, proper welding procedures were implemented, and work was performed by qualified welders; verified that other contractors examined every weld joint for compliance to API 1004 specifications and each weld passed non-destructive testing
• Coating Inspectors (NACE Level 1 Certified) – Inspected pipe and weld coatings for defects and damage prior to all backfills, HDD pull-throughs, or jack and bores; verified all field-applied pipe coating met Nicor’s mill thickness and the manufacturer’s hardness specifications; verified coating was protected during installation and not damaged during pull-through activities
• Utility (General) Inspectors – Provided continuous daily oversight of individual project segments to verify that construction adhered to schedule, design, and specifications; ensured compliance with all permit and JULIE requirements; validated that environmental best management practices were followed in accordance with permits and construction plans; and coordinated construction activities with landowners as needed