Change orders represent a cost to the State and to tax payers that often extremely large because contractors tend to charge very large amounts to any additional work that deviates from the work that was originally planned. Therefore, efforts must be made to reduce the occurrence of change orders in order to provide significant cost savings to the state of Indiana and save taxpayer dollars. The proposed research, in this context, developed a set of guidelines to allow the geotechnical office of the Indiana Department of Transportation (INDOT) to minimize the probability of having geotechnical change orders, based on analysis of past data and interviews with INDOT personnel.

From 300 INDOT contracts, it was found that the average geotechnical change order amount per district per year was 1.34 percent of the total estimated construction cost per district per year. The average geotechnical change order amount per district per year was 10.25 percent of the average amount of total change orders per district per year. 28 percent of the contracts experienced geotechnical change orders. 41 % of the total road contracts experienced geotechnical change orders. Soils-Related reason codes 206 – Constructability, 405 – Changed Field Conditions, 108 – Errors and Omissions were assigned to 101,46 and 11 geotechnical change orders respectively. INDOT personnel who were interviewed, recognized the need to address the following issues that lead to geotechnical change orders (i) Failure to identify areas of poor subgrade soil (ii) Mismatch in piling quantities (iii) Omissions and constructability issues associated with erosion control work.

Report Number



Change Orders, Cost Savings, Geotechnical Change Orders, Reason Code, Errors and Omissions, Constructability Issues, Changed Field Conditions, SPR-3224

SPR Number


Performing Organization

Joint Transportation Research Program

Publisher Place

West Lafayette, Indiana

Date of this Version


3224_TechnicalSummary.pdf (221 kB)
Technical Summary