Ehrhart Griffin & Associates (EGA) was a member of the design team led by Lamp, Rynearson and Associates, selected by the City of Omaha to prepare construction documents for the massive site demolition and environmental cleanup efforts, together with the site preparation for construction of the infrastructure around the City’s new $288 million dollar Convention Center/Arena. The Convention Center/Arena occupies a 110-acre site that once was home to the Union Pacific Railroad yard. EGA’s scope of work of the design team included the prep-aration of construction documents for the demolition of existing railroad facilities.

EGA was responsible for the preparation of construction documents and the construction management of the four phases of demolition of the project site. The site at the time of demolition held only four major structures but had previously housed approximately 100 buildings of varying sizes and uses. An extensive array of historical documents, some dating back to 1898, that portrayed the historical development of the project site were made available from Union Pacific Railroad’s Engineering Division.

Members of the EGA staff researched the pertinent documents in order to determine the existence and location of all previously demolished buildings and utilities. In almost all cases, these previous buildings were removed only to existing grade, leaving footings, pilecaps, foundations, piles, and floor slabs in place. Clear zones for utility extensions and building foundation elements were identified early in the design process in order to minimize the financial impact of the demolition upon the project budget. Demolition techniques utilized to keep construction costs minimized included the crushing of existing pavement into structural fill material for re-use onsite.

Close coordination was also necessary with UPRR and their environmental consultants as they began their efforts to meet the environmental limits established for the project site. The contracts for the first three demolition phases were awarded in the summer of 2000, with completion of the demolition by 2002.

Construction obstacles included poor soils conditions and high groundwater tables. Close coordination with all public utility companies was critical during the demolition process and the design process as well.