Cost Estimation and Production Evaluation for Hopper Dredges

Abstract

Dredging projects are expensive government funded projects that are contracted out and competitively bid upon. When planning a trailing suction hopper dredge project or bidding on the request for proposal for such a project, having an accurate cost prediction is essential. This thesis presents a method using fluid transport fundamentals and pump power characteristics to determine a production rate for hopper dredges. With a production rate established, a number of financial inputs are used to determine the cost and duration of a project. The estimating program is a Microsoft Excel spreadsheet provided with reasonable values for a wide arrange of hopper dredging projects. The spreadsheet allows easy customization for any user with specific knowledge to improve the accuracy of his estimate. Results from the spreadsheet were found to be satisfactory using the default values and inputs of 8 projects from 1998 to 2009,: The spreadsheet produced an estimate that was an average of a 15.9% difference from the actual contract cost, versus a 15.7% difference for government estimates of the same projects.