Approved by the Energy, Environment, and Water Policy Committee on December 17, 2018
Approved by the Public Policy Committee on April 28, 2019
Adopted by the Board of Direction on July 13, 2019
The American Society of Civil Engineers (ASCE) supports regional sediment management for watershed and coastal zones to ensure ecosystem preservation and sustainable development. Regional sediment management is critical to restoring hydrogeomorphic processes within a watershed, and reducing vulnerability, which in turn is important to ecosystem vitality, balance and diversity, particularly in threatened ecosystems. ASCE recommends:
- Government and private entities that develop or execute projects and activities affecting water resources or hydrogeomorphic processes, and related regulatory entities, promote a culture of stewardship and partnering to manage sediments effectively and mitigate adverse impacts;
- Sediment should be managed as a finite resource by developing regional sediment inventories and sediment budgets that consider long-term sustainable inputs, movements, uses, and outputs throughout the system, with a concentration on restoring natural sediment transport once disrupted by past unsustainable construction and practices;
- Governments and stakeholders at all levels should improve and encourage collaboration to establish property rights for sediment, and an appropriate legal mechanism to allocate and transfer sediment resources for different uses, and to resolve conflicts among multiple competing demands for the same sediment source; and
- Proponents of projects and activities that affect sediment resources must work collaboratively with regional stakeholders to mitigate adverse impacts to hydrogeomorphic processes and affected sediment regimes.
Regional sediment management is an approach for managing projects that incorporates the principles of integrated watershed resources management and improved dredged material management. It recognizes sediment as a resource, and the need to consider projects and actions affecting sediment in a regional context.
Sediment movement and deposition on a regional scale are integral to the key hydrogeomorphic processes critical to ecosystem health associated with waterways and aquatic habitats. Long-term alterations of sediment regimes can significantly modify critical habitat, stress ecosystem integrity and vitality, and could cause regional-scale ecosystem collapse. Degraded ecosystem health translates into increased risk to life and property, as well as increased costs in addressing related social, economic, and environmental problems. Linking sediment management needs and opportunities can enhance the benefits of multiple projects and activities within a region, both economically and environmentally.
Regional sediment management is critical for preserving and restoring wetlands. It is also important to achieving the goal of restoring and maintaining the chemical, physical, and biological integrity and biodiversity of waters and associated aquatic habitats. It is integral to effective implementation of the watershed approach to managing water resources. Regional sediment management integrates actions that affect the erosion, transport, deposition, and removal of sediment in a region. Knowledge of the sediment system in a region is essential for making local water resource project decisions and establishing longer-range strategies. Effective implementation of regional sediment management will restore vital hydrogeomorphic processes with related ecological benefits.
ASCE Policy Statement 522
First Approved in 2007