Outsourcing of project activities at State Transportation Agencies (STA) to the private sector has become ubiquitous over the last several decades. This trend of increased outsourcing is primarily driven by the continued demand for public transportation infrastructure coupled with static or declining levels of in-house STA employees. Many prior studies have reported on the trends, impacts, challenges and costs of outsourcing functions, such as design, but few have focused on the use of consultants specifically for testing and inspection. This paper synthesizes the current state of practice of outsourcing testing and inspection activities across STAs within the United States. Specifically the study used a qualitative approach which included a literature review, surveys of STAs on their current state of practice for outsourcing testing and inspection, questionnaires of consultants that provide inspection services to the Indiana Department of Transportation (INDOT), follow-on interviews with key STAs, and interviews with five Indiana DOT district construction directors to determine the following:

  1. Factors/criteria for determining the basis for outsourcing inspections and testing
  2. Factors influencing the motivation and decision to outsource testing and inspection
  3. Documents and guidelines used for ensuring quality in outsourced tests and inspections
  4. Benefits and advantages realized through outsourcing testing and inspection

In addition to a synthesis of the current state of outsourcing across the STAs, five key strategies were identified to guide STAs with outsourcing testing and inspection activities. The key strategies include: (1) conducting strategic level planning, (2) developing a system of record to track in-house versus consultant cost, (3) maintaining a strong prequalification program, (4) consistently evaluating consultant performance, and (5) providing training to in-house staff and consultants. Application of these strategies can assist STAs in developing, sustaining, and guiding a quality testing and inspection outsourcing program.

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outsourcing, inspection, materials testing, consultant, CEI, conflict of interest, prequalification

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Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, Indiana

Date of this Version