A3 Underground Construction is central and southwest Idaho’s best choice for high quality, cost-effective septic system installation and repair, underground drainage solutions, and trenching, grading, and excavating services. We have over 30 years of experience, extensive industry knowledge, and a fleet of well-maintained demolition and construction equipment. Not only are we are a fully licensed and insured excavation and septic system contractor, but we’re also one of the few state-certified complex septic system installers serving the Boise Metropolitan area. Call today to arrange an on-site consultation anywhere in or near Boise, Nampa, Meridian, Middleton, Caldwell, McCall, New Plymouth, and Midvale.