A dredger is a tool. For hundreds of years, this tool has been used to shape and manipulate the interface between land and water in order to support a variety of human activities, including navigation, coastal protection, flood risk management, as well as residential, commercial, agricultural and hydro-power development, the International Association of Dredging Companies (IADC) said in their Terra et Aqua magazine.
The use of dredging to achieve these purposes has always been guided by an understanding of the costs and benefits of applying the tool.
However, in the last several decades, the understanding of what constitutes costs and benefits has evolved substantially beyond the direct monetary costs of using the tool and the direct monetary benefits of what the tool was used to create. Over the last 50 years, the cost-benefit evolution was aided by the environmental movement.
The Broad Context
For the last several decades, dredging has found itself at the center of a fundamental conflict between supporters of development and the environment. To minimize the adverse effects of dredging activities on ecosystems, environmental regulations were put in place. The environmental regulations put into place intend to eliminate, reduce, or control the impacts of dredging on the environment have produced a range of outcomes, both positive and negative.
It is undoubtedly true that such regulations have helped to reduce negative impacts on the environment, in general. However, it is also true that the amount of environmental benefit produced by such regulation has not been systematically quantified, let alone compared to the social and economic costs and the shift of negative impacts to other systems due to reduced efficiency of the construction works of such regulation.
Today, a paradigm shift is increasingly being embraced within the dredging industry, truly changing the traditional engineering approach into a holistic approach in which the ecosystem is leading and values for people, profit and planet are integrated in an interdisciplinary manner.
The Growing Focus on Sustainability
The International Focus An increasing amount of attention is being given to the concept of sustainability as an approach to informing social, environmental and economic development.
In 2015, the United Nations released its Sustainable Development Goals (SDGs) as a part of its 2030 Agenda for Sustainable Development.
A total of 17 goals were established and encompass a very broad range interests, values and objectives. As a means for developing water resources infrastructure, the relationship of dredging to each the SDGs varies from weakly to strongly connected.
For example, the use of dredging to construct efficient and productive navigation infrastructure is directly connected to SDGs 2, 7, 8, 9, 10, 11, 12, 13, 15 and 16. As a tool used to provide coastal protection and infrastructure supporting flood risk management, dredging clearly supports SDGs 1, 3, 7, 10, 12 and 14, among others.
In the future, one of the challenges that should be addressed by the dredging and water infrastructure community is to incorporate these goals into the infrastructure development process and to become effective at communicating how such projects support the SDGs.
The Sector-Specific Focus
On behalf of the dredging sector, the World Organization of Dredging Associations (WODA) – which includes the Central Dredging Association (CEDA), the Eastern Dredging Association (EDA) and the Western Dredging Association (WEDA) – published its principles of sustainable dredging in 2013.
The WODA principles reflect the importance of using dredging to create value across the three pillars of sustainability, considering the system-view of projects including the ecosystem and natural processes operating within the system, and the role of engaging stakeholders including project proponents, regulators and the broader array of interests relevant to a project.
Publication of the WODA principles has sparked a range of discussions and actions within the dredging sector in efforts to seek a balance between the economic development that is supported through dredging and environmental considerations and regulation.
Disseminating information throughout the industry
Alongside the growing public awareness of the need for sustainability, there has been an increasing sense of individual and corporate responsibility regarding the consequence of dredging activities on the environment. In 2008, a team of experts brought together by CEDA and IADC compiled their knowledge – as well as information available in less comprehensive, earlier publications – into a single, up-to-date volume.
The Environmental Aspects of Dredging (Bray, 2008) brought the impacts of dredging to marine environments into industry focus in an effort to inform a project’s manifold stakeholders while complying with international legislation.
A myriad of methodologies are presented to mitigate the negative effects of dredging on water quality and contaminated soils as well as minimizing loss of habitats and fauna. In the years following the release of the Environmental Aspects of Dredging, an update of its information was prepared to ensure it evolved with the industry’s practices as well as legislation. After consideration by an editorial advisory board of industry experts, it was collectively agreed upon that a mere revision of the presented information was not enough and an entirely new publication was needed.
The principles and methodologies were updated, refined and expanded upon. An updated successor makes its debut as Dredging for Sustainable Infrastructure later this year, once again the result of a joint effort by CEDA and IADC.
Applying the concept of sustainability to water infrastructure development
The concept of sustainable development is based on the premise that the design for an action – in this case a development project that involves the use of dredging – will be informed by a full consideration of the values and costs of the proposed action across the three pillars of sustainability.
The outcomes expected from the action may be categorized as social, environmental and economic outcomes. The concept of sustainable development recognizes the need to consider the full range of benefits and impacts related to human actions and the distribution of these benefits and costs across the social, environmental and economic domains.
The relationships among these value domains are reflected by the goal to take actions – such as developing projects – that will balance the distribution of benefits and costs so as to produce socially equitable, environmentally acceptable, and economically viable outcomes.
This balance is achieved through active and consistent engagement with the stakeholders which will be affected by the proposed project. Stakeholders may include local, regional and national members of the public, government authorities, private sector interests and special interest groups as well as perspectives that are relevant to the project.
In order to aid the discussion of sustainability in the context of infrastructure development and dredging, the following operational definition is proposed: Sustainability is achieved in the development of an infrastructure by efficiently investing the resources needed to support the desired social, environmental and economic services generated by the infrastructure for the benefit of current and future generations.
The new publication is an authoritative guide on delivering dredging projects that enhance the natural and socio-economic systems, and will be an invaluable resource for those responsible for delivering projects with longevity which need to do more than just the basics.
Project owners, regulators, consultants, designers and contractors looking for an up-to-date reference should find it to be a useful tool. The team of expert authors represents international institutes, dredging contractors, consultants and project owners.
Edited and published by CEDA and IADC, Dredging for Sustainable Infrastructure will be available in a print and e-book edition.
A special conference and course will be held on the subject.