The Impact of Procedural Factors on Granulometric Analysis: Implications for the Economic Viability and Success of Coastal Nourishment Projects

Coastal erosion represents a major challenge for shoreline management globally, with beach nourishment being the most widespread mitigation strategy. The effectiveness and longevity of these projects critically depend on the granulometric compatibility between borrow and native sediments, requiring a precise characterization of both materials.
However, the characterization of borrow sediment is influenced by a set of factors during the analysis procedure that can introduce considerable uncertainty into the results. Essential variables such as the sampling technique, sediment variability within the dredge hopper, sieving specifications (e.g., column diameter and sieving time), and the sample drying method have been shown to have a substantial quantitative impact on the final findings.
This work presents a comprehensive review of research quantifying the influence of these factors on the accuracy of granulometric analysis. The magnitude of the cumulative error is assessed, demonstrating how minor procedural inconsistencies can lead to significant deviations in key sediment parameters like mean grain size and sorting. Such deviations have direct implications for calculating the required nourishment volume, resulting in significant errors in the estimated quantity. These miscalculations directly compromise the economic viability of the project by creating a critical mismatch between the designed and the truly necessary sand volume. In response, standardized protocols are proposed to mitigate these uncertainties and enhance the predictability and effectiveness of future nourishment interventions.