Offshore windfarm foundation and trench dredging - Procurement challenges and the role of integrated monitoring
Type:
Presented during:
CEDA Dredging Days 2026
Authors:
S. Burgmans, S. Nanayakkara and N. Dalziel
Abstract
Dredging often accounts for a significant portion of offshore windfarm installation budgets, making early stage realistic cost definition critical to project feasibility. In practice, owners often require budget certainty long before construction begins. While early contractor engagement may provide useful insights, contractor estimates are frequently optimistic or incomplete, leaving owners without robust cost clarity at precisely the stage when it is most needed. Procurement models add further complexity. In large framework agreements, dredging may be bundled with foundation and turbine installation works, given that most dredging contractors are equipped to perform both. Although integration can deliver efficiencies, it also reduces market competition. As contractors recognise this, risk allocation shifts. Productivity risks, once normally absorbed under lump-sum contracts are increasingly passed back to owners. This trend has led to more work executed on daily rates, exposing owners to the consequences of lower-than-expected productivity. In such circumstances, effective monitoring becomes vital. With limited contractual incentives to optimise performance, inefficiencies can quickly erode budgets and schedules. However, integrated monitoring frameworks, which combine vessel logfiles, progress surveys, vessel specifications and progress reports, provide owners with the necessary transparency. When analysed by experienced specialists, these data streams enable early detection of bottlenecks, objective contractor performance assessments and early-stage dispute resolution. This paper presents case studies showcasing i2D's integrated monitoring methodologies, which combine shadow estimates with equipment performance reviews. These approaches have provided valuable insights, such as detecting dredging operations running close to vacuum limits at maximum trail speed, verifying compliance with environmental dumping permits and conducting forensic analyses of non compliance. The results demonstrate that, while lump-sum contracts remain the most effective means of transferring productivity risk to contractors, when daily rate contracts are unavoidable, integrated monitoring is essential to safeguard project budgets and delivery schedules.