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5H - Catchment area mgnt (WEP/217) European sediment management strategies: balancing quantity and quality. White, Sue1, Apitz, Sabine1, 1 Cranfield University, Silsoe, Bedfordshire, UK ABSTRACT- With the introduction of the European Water Framework Directive, there has been a shift in the scope of water management from local to catchment scale. In parallel, there is a need for a European approach to environmentally, socially and economically viable sediment management on a river basin scale. Most management frameworks currently under development throughout the world by definition have had a major focus on the assessment and management of CONTAMINATED sediments (and thus sediment quality). However, if sediments are to be managed on a river basin scale, across boundaries, ecosystems, and various land and water uses, sediment management frameworks must embrace a broader remit, the management of sediments in terms of both quantity and quality. Sediment quantity alone must be incorporated as a critical aspect of a sediment management decision framework, even when sediment quality is not an issue. While all parties are aware of the need to move sediments (which may or may not be contaminated) in support of navigation and construction, sediment quantity alone as a risk driver and a resource are not yet formally part of sediment decision strategies. Sediment quantity issues cover the range of excess, lack and imbalances in the dynamic sediment supply-transport-deposition system, resulting in a variety of economic and environmental costs and benefits including loss of soil (and associated fertilizers, pesticides, bacteria etc) from farmland, loss of availability of aggregates for construction, erosion of channels and subsequent infrastructure damage, siltation of lakes and impounded water bodies, habitat change, and increasing flood levels. Some approaches to how these issues can be formally inserted into risk assessment frameworks, and their implications to river-basin scale sediment management, will be discussed. Key words: river basin, sediment, quantity, risk |
