EGU23-13625, updated on 26 Feb 2023
EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

MODWT-based outflow decomposition and individual contribution of regulation sites over Paranapanema river basin

Thais Fujita1,6, Luz Adriana Cuartas2,6, Juliana Andrade Campos3,6, Caluan Rodrigues Capozzoli1,4, Jorge Alberto Martins5, Edmilson Dias de Freitas1, and Cintia Bertacchi Uvo6,7
Thais Fujita et al.
  • 1Institute of Astronomy, Geophysics and Atmospheric Sciences, University of São Paulo, São Paulo, Brazil (
  • 2National Center for Monitoring and Early Warning of Natural Disasters, São José dos Campos, Brazil (
  • 3Institute of Hydraulic Research, University of Rio Grande do Sul, Porto Alegre, Brazil (
  • 4Geological Survey of Brazil, São Paulo, Brazil (
  • 5Graduate Program in Environmental Engineering, Federal University of Technology—Paraná, Londrina, Brazil (
  • 6Division of Water Resources Engineering, Lund University, Lund, Sweden (
  • 7Finnish Environment Institute, Helsinki, Finland (

The viability of hydropower production depends on water and energy distribution, storage capacities, and technical constraints. Understanding the sensitivity of runoff variability to hydroelectricity production is a step to better assess its potential and add value to society. In this study, we explored the decomposition of hourly outflow data of hydropower power plants (HPP) operation for a 22-year period into scale-dependent coefficients using the maximal overlap discrete wavelet transform (MODWT) over the Paranapanema river basin. The wavelet analysis of the historical time series shows that the operational coordination of the cascade hydropower system leads the watershed to behave as a space-time filter. This filtering is applied to the process of temporal aggregation of rainfall into the generation of runoff and results in periodic fluctuations due to retention and release of outflow in regulation sites, from run-of-river facilities and regulation dams. These regulated patterns manifest over several scales, dominated by hydropeaking, and diminished seasonal signals.

We found that MODWT effectively describes the broadband of sub-daily and weekly flow cycles from fluctuating electricity demand. The decomposition analysis, which partitions the signal's energy across detail coefficients and scaling coefficients, also showed that the recognition of site-specific, each HPP, infers the individual filtering contributions of regulation points and provides a complementary metric to identify the practices and policies that affect outflows across the watershed. The increase in total energy by scales, the sum of decompositions, from upstream to downstream indicates the presence of spatial and temporal relationships with outflow magnitude. In addition, it highlights the coordination of the joint operation and how its cumulative effects serve energy generation, which implies matching consumer demand and supply.

How to cite: Fujita, T., Cuartas, L. A., Andrade Campos, J., Rodrigues Capozzoli, C., Alberto Martins, J., Dias de Freitas, E., and Bertacchi Uvo, C.: MODWT-based outflow decomposition and individual contribution of regulation sites over Paranapanema river basin, EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-13625,, 2023.