Impacts of dredging in rivers is always a cause of concern especially when this is conducted on large rivers that are part of the Amazon River watershed. Recently the Peruvian government has created Hidrovias Amazonicas project that will enhance the navigability on four large rivers: Huallaga, Amazon, Marañon and Ucayali. As part of that project 2,687 km of reach length on those rivers will be dredged at 13 locations which has raised social and environmental concerns in the area. Numerical models were created to shed light of the impacts of these dredging operations. The input for these numerical simulations consisted of field data collected in an area of about 210,000 Ha which included bathymetric surveys, velocity and flow measurements, water levels and bed and suspended material lab tests. The models were developed and calibrated in TELEMAC2D and DELFT3D which allowed a reasonable prediction of hydrodynamics, Total Suspended Solids (TSS) concentration and bed load for different scenarios. The results indicated that a) the TSS concentration and the grain size influences significantly the near-field dispersion whereas the mixing and flocculation influences the far-field dispersion, b) the water level is a dominant parameter on the plume turbidity plume in meander rivers, c) in anabranching rivers the Van Rijn dispersion equations (2019) over predicts in the near-field and under predicts on the far-field the maximum TSS concentration value.
|Number of pages||1|
|Publication status||Published - 2019|
|Event||AGU Fall Meeting 2019 - San Francisco, United States|
Duration: 9 Dec 2019 → 13 Dec 2019
|Conference||AGU Fall Meeting 2019|
|Period||9/12/19 → 13/12/19|