The Huntley-Ledyard project is part of the Minnesota-Iowa Transmission Project, connecting Iowa to Minnesota. This segment involved 23 miles of new 345/161 kV transmission line connecting the new Huntley Substation to the new Ledyard Substation.
VE Bid Alternative
Quanta Subsurface (QS) worked with MJE Drilling to value engineer several foundations on the alignment and present an alternate bid to the owner. Acting as the foundation Engineer of Record, QS redesigned the select shafts to match site-specific geotechnical profiles and optimize MJE Drilling’s installation means and methods. The collaboration produced cost and schedule savings which were a major factor in the contract being awarded.
Transmission structure base reactions were analyzed to match foundation structural capacity and performance with the Owner’s needs, while reducing the additional conservatism of the base bid designs. QS worked closely with MJE Drilling Project Management to optimize foundation sizing specific to their tooling and construction capabilities.
Challenges & Outcome
Project challenges included working with limited geotechnical data and having to focus design efforts on specific areas of the alignment to accommodate accelerated scheduling requirements. Understanding MJE Drilling’s critical path schedule allowed for a staggered submittal approach and early design review, ultimately limiting risk to the project schedule. Working in conjunction with MJE Drilling and the Owner also allowed for accelerated delivery of structure loading and connection information.
In total, QS provided designs for 132 drilled shafts and reduced overall concrete volume by approximately 15%.