Nexus Alliance NA Team

Mike Kleffner, PE

Principal / Projects Engineer

Michael Kleffner P.E.  has over 20 years of experience in the Engineering and Construction Industry. His experience includes working as the Construction Engineer for the City of Omaha, Urban Engineer for the Nebraska Department of Transportation, Project Engineer for Olsson Associates and Field Engineer for Nebraska Department of Transportation.  Michael’s previous experience in both the private and public industry allows him to see the issues that public entities experience with public involvement, design issues and funding along with many other facets during the project lifespan.  Some of the areas that Michael has extensive experience include Construction Inspection & Testing, Program Management, Water & Wastewater System Design, Roadway Design, S.I.D. Development, Trail Design, Project QA/QC & Constructability, Public Involvement and Historic Roadway Improvement.

David Nassi, PE

Project Manager / Engineer

David Nassi P.E. has experience working as a Roadway Design Engineer for the Nebraska Department of Transportation and the Street Improvement District Engineer for the City of Omaha.  David has managed Transportation projects from concept through construction and is intimately familiar with Nebraska DOT and Omaha Metro Area design and construction specifications and processes. David’s previous project experience includes Wastewater & Stormwater, Roadway Widening, New Construction and Streetscape Rehabilitation.    

William Herr

Project / QAQC Manager

William Herr has managed Transportation projects from Design through Construction for the Sarpy County Public Works Department for over 30 years. William has managed all aspects of a project and managed multiple types of projects including new construction, roadway rehabilitation, roadway widening, new bridge construction, bridge replacement, federal aid projects and traffic operations projects.  William’s civic participation includes the Technical Transportation Committee for Omaha MAPA, Executive Board for the Nebraska APWA, and the Planning Committee for the Nebraska Concrete Pavers Association.