We take you where you want to go.

Why should you choose Commonwealth for your upcoming transmission and distribution project? It’s simple. Our diverse staff represents one of the most experienced transmission and distribution technical resources available to the electric energy industry worldwide. We design new facilities and expand and upgrade existing ones in voltages from 4.8 kV to 765 kV at costs between a few thousand and several million dollars. We are actively engaged in the development and assessment of the most advanced power delivery systems – overhead, underground, and submarine – and use the latest technological tools to complement our world-class engineering skills.

We offer:

Transmission LIne Services

  • Route Selection and Permitting
    • Select routes that minimize impacts to natural and cultural resources
    • Participate in public informational meetings
    • Prepare applications for permits, licenses, or other approvals
  • Conceptual Design Studies
    • Design Criteria Studies – evaluate and recommend design criteria for use in economic studies based on safety codes and meteorological and environmental conditions
    • Economic Conductor Studies – evaluate alternate conductor types (ACSR, ACAR, ACSS, SDC, T2, AAC, and any of the new high-temperature, low-sag conductors) sizes, number of subconductors, and phase bundle configurations
    • Electrical Environmental Effects – evaluate effects resulting from electric and magnetic fields and audible and radio noise
    • Structures – evaluate alternate structure types for cost and constructability
    • Foundations – evaluate alternate foundation types for structures, based on access, constructability cost, and general soils data available from existing area records
    • Shield Wire Coordination – evaluate alternate shield wires to select optimum size and type, including the use of grounded, insulated, or optical ground wires
    • All Dielectric Self-Supporting Fiber Optic Cable Coordination
    • Insulation and Hardware – make appropriate recommendations for support systems, configuration, strengths, and maintenance
    • Grounding – in terms of economy and reliability, evaluate alternate grounding systems
    • Final Design Summary – summarize design criteria and conceptual design studies
    • Underground Transmission – study feasibility and cost of special cable applications
  • Detail Engineering
    • Engineering and Design Services
      • Coordinate surveys and prepare plan and profile drawings
      • Provide assistance in right-of-way procurement
      • Design right-of-way drainage and access roads
      • Prepare structure application charts
      • Locate structures on centerline manually or with PLS-CADD, utilizing established design criteria
      • Prepare plan and profile drawings in AutoCAD or MicroStation, incorporating latest technology for plan views
      • Prepare environmental management and construction plans
      • Prepare structure concept and loading drawings in AutoCAD or MicroStation format
      • Prepare structure analysis, member sizing, and design drawings
      • Determine soil design parameters from borings and lab data
      • Perform tower site inspection
      • Design structure foundations
      • Prepare crossing permit drawings
      • Design major river crossings
      • Design optical ground wire and ADSS installations or replacements
      • Coordinate transmission design with distribution
      • Design underground and submarine transmission and distribution
      • Analyze existing transmission line structures for installation of fiber optic cable and develop recommendations for structural modifications, if necessary
      • Conduct economic evaluation of line route alternatives for fiber optic networks
      • Provide site planning and engineering for communications equipment buildings
      • Preparation of fiber optic cable system maps
      • Evaluate impact of PCS devices added to transmission structures, including use of EIA/TIA standards
    • Drawings and Related Services for the Purchase of Line Materials
      • Prepare specifications for shop detailing and fabrication of structures
      • Develop structure, foundation, and electrical load test programs and witness tests
      • Prepare purchase specifications for all line material
      • Provide pre-bid drawings, schedules, and evaluations
      • Provide review of manufacturers’ drawings
      • Perform purchasing and expediting services
      • Line Construction Services
        • Prepare construction drawings
        • Prepare stringing sag-tension data and conductor offset clipping data
        • Prepare construction specifications
        • Prepare turnkey construction bid packages
        • Conduct pre-bid meetings to review specifications and drawings
        • Prepare project cost estimates
        • Develop cash flows and schedules
        • Evaluate construction bids
        • Participate in re-construction meetings
        • Provide engineering liaison with construction management
        • Develop and present training programs

    Distribution Line Services

    • Overhead Distribution
      • Conductor selection
      • Structure design and detailing
      • System layout and structure spotting
      • Structure application
      • Conductor sag charts
      • Bills of material
      • Construction drawings
    • Underground Distribution
      • Calculations for:
        • Cable ampacity
        • Induced voltage on cable shield
        • Voltage regulation
        • Conduit fill and jam ratios
        • Cable pulling tensions
      • Economic comparisons
      • Cable selection
      • Associated URD equipment selection
      • Duct and manhole design
      • Tunnel design
      • Plan and profile drawings
      • Distribution standards
    • Procurement / Bid Services
    • Equipment Specifications

Project: ITC Cobb Swamp

Location: Michigan

The Challenge: Rebuilding 138 kV line in wetlands, requiring significant environmental permitting, despite very challenging construction access and the presence of 7 state- and federally regulated species.

The Result: Working with the client, Commonwealth successfully designed a construction phasing and outage plan, ensuring timely and cost-effective completion, minimal public disruption, and total regulatory compliance.

Click HERE to learn more about our projects.
Contact Gary Bernstein at 517.990.8353 or Gary.Bernstein@cai-engr.com.