Date of Award


Document Type

Doctoral Thesis

Degree Name

Doctor of Philosophy


Civil, Structural & Environmental Engineering

First Advisor

Dr. Joseph Harrington


This thesis examines the use and applicability of a range of dredge material management techniques for the Republic of Ireland which will ultimately assist the stakeholders in the industry in assessing the available dredge material management options. A detailed study is presented into the critical parameters required for successful implementation of a range of dredge material management options. An overview of the Irish dredging industry including current dredge material management practice is presented. This is complemented by a detailed critical analysis of the industry which identifies areas requiring development and future challenges for the dredging industry in Ireland. To further the knowledge base of innovative beneficial uses, a primary finding of the critical analysis undertaken, detailed analyses are undertaken on specific sites without a history of beneficial use.

An analysis of producing manufactured topsoil product from the Port of Waterford’s maintenance dredge material includes a survey of public perception of the scheme, developing and testing a treatment process, undertaking growth trails and statistical analysis, and determining the implications, economic and CO2 emissions, of integrating the beneficial use scheme into the annual maintenance dredging program. The production of manufactured topsoil can be integrated into an annual dredging program in a feasible manner if the technical features of the available dredgers are suitable, the topsoil demand in the area is sufficient and the disposal at sea distance is considerable. Dredge material from Fenit Harbour is also assessed as a potential fill material for use in geotubes to form part of a coastal protection structure. The analysis identifies the structural design implications of the use of geotubes as well as the impact on the economics and CO2 emissions with comparison to traditional rubble mound structures. Geotubes, with the use of dredge material, may provide a sustainable beneficial use for dredge material in coastal areas with low wave energy and may offer a serious economic and environmental alternative to traditional rock structures. The outputs from the research will allow greater consideration of these innovative beneficial use options through greater understanding of their individual merits and implications.

A decision support software program called 'Dredge Material Management Assessment Program' (DMMAP) is developed allowing analysis to be undertaken to determine the feasibility of a range of beneficial uses of dredge material, its suitability for disposal at sea, or its viability for a range of different treatment processes for contaminated material. A site specific analysis for land reclamation at the Port of Cork using DMMAP demonstrates the applicability of the program. Sensitivity analyses are also undertaken using DMMAP to identify the most critical economic and CO2 emission parameters for each of the beneficial use schemes analysed.

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