Simulation of fluvial sediment dynamics through strategic assessment of stream gaging data: A targeted watershed sediment loading analysis. (1st January 2021)

• Record Type: Journal Article
• Authors: Cho, Se Jong; Braudrick, Christian A.; Dolph, Christine L.; Day, Stephanie S.; Dalzell, Brent J.; Wilcock, Peter R.
• Is Part Of: Journal of environmental management. Volume 277(2021)
• Publication Date: 2021-01-01
• Subjects: Sediment transport -- Near-channel sediment -- Stream erosion -- Bluff erosion -- Minnesota river; Environmental policy -- Periodicals; Environmental management -- Periodicals; Environment -- Periodicals; Ecology -- Periodicals; 363.705
• DOI: 10.1016/j.jenvman.2020.111420
• Languages: English
• ISSNs: 0301-4797

Abstract

Abstract: Near-channel sediment loading (NCSL) is localized and episodic, making it difficult to accurately quantify its cumulative contribution to watershed sediment loading, let alone predict the effects from changes in river discharge due to climate change or land management practices. We developed a methodological framework, using commonly available stream gaging data, for estimating watershed-scale NCSL, a feature generally absent in most watershed models. The method utilizes a network of paired gages that bracket the incised river corridors of 15 tributaries to the Minnesota River, in which near-channel sources are often the dominant contributors of sediment loading. For each set of paired gages, we calculate NCSL as the difference between the upstream and downstream sediment loading minus the field contribution between the gages. NCSL generally increases with river discharge when it exceeds the observed threshold benchmark in the tributaries of Minnesota River Basin; accordingly, we developed a predictive model for quantifying NCSL using river discharge as the independent variable. This approach provides a predictive basis for evaluating the impacts on near-channel sediment supply from increases in runoff and river discharge. Application of this approach includes evaluation of watershed-scale conservation trade-offs, where benefits of landscape management practices, such as wetlands and reservoirs are measured in terms of reduction in downstream near-channel sediment loading in the incised river corridors. Graphical abstract: Image 1 Highlights: Near channel sediment loading is quantified and simulated with strategic assessment of gage data. Gage locations and watershed conditions influence model formulation and sources of uncertainty. Land management using water storage can be informed to reduce downstream channel erosion.