Amplification of downstream flood stage due to damming of fine-grained rivers.

Autor: Ma H; Department of Civil and Environmental Engineering, University of California at Irvine, Irvine, CA, USA. bigmatton@gmail.com., Nittrouer JA; Department of Geosciences, Texas Tech University, Lubbock, TX, USA. jeffrey.nittrouer@ttu.edu., Fu X; State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing, China. xdfu@tsinghua.edu.cn., Parker G; Department of Geology, University of Illinois, Urbana-Champaign, IL, USA.; Department of Civil and Environmental Engineering, Ven Te Chow Hydrosystems Laboratory, University of Illinois, Urbana-Champaign, IL, USA., Zhang Y; Yellow River Institute of Hydraulic Research, Zhengzhou, Henan, China., Wang Y; Yellow River Institute of Hydraulic Research, Zhengzhou, Henan, China., Wang Y; State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing, China., Lamb MP; Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA., Cisneros J; Department of Geology, University of Illinois, Urbana-Champaign, IL, USA., Best J; Department of Geology, University of Illinois, Urbana-Champaign, IL, USA.; Department of Civil and Environmental Engineering, Ven Te Chow Hydrosystems Laboratory, University of Illinois, Urbana-Champaign, IL, USA.; Department of Geography and Geographic Information Science, University of Illinois, Urbana-Champaign, IL, USA.; Department of Mechanical Science and Engineering, University of Illinois, Urbana-Champaign, IL, USA., Parsons DR; Energy and Environment Institute, University of Hull, Hull, UK., Wu B; State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing, China.
Jazyk: angličtina
Zdroj: Nature communications [Nat Commun] 2022 Jun 01; Vol. 13 (1), pp. 3054. Date of Electronic Publication: 2022 Jun 01.
DOI: 10.1038/s41467-022-30730-9
Abstrakt: River dams provide many benefits, including flood control. However, due to constantly evolving channel morphology, downstream conveyance of floodwaters following dam closure is difficult to predict. Here, we test the hypothesis that the incised, enlarged channel downstream of dams provides enhanced water conveyance, using a case study from the lower Yellow River, China. We find that, although flood stage is lowered for small floods, counterintuitively, flood stage downstream of a dam can be amplified for moderate and large floods. This arises because bed incision is accompanied by sediment coarsening, which facilitates development of large dunes that increase flow resistance and reduce velocity relative to pre-dam conditions. Our findings indicate the underlying mechanism for such flood amplification may occur in >80% of fine-grained rivers, and suggest the need to reconsider flood control strategies in such rivers worldwide.
(© 2022. The Author(s).)
Databáze: MEDLINE
Externí odkaz: